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Sagara I, Healy SA, Assadou MH, Kone M, Swihart BJ, Kwan JL, Fintzi J, Sissoko K, Kamate B, Samake Y, Guindo MA, Doucoure M, Niaré K, Dolo A, Diarra B, Rausch KM, Narum DL, Jones DS, MacDonald NJ, Zhu D, Gorres JP, Imeru A, Mohan R, Thera I, Zaidi I, Salazar-Miralles F, Duan J, Neal J, Morrison RD, Muratova O, Sylla D, O'Connell EM, Wu Y, Hume JCC, Coulibaly MB, Anderson CF, Traore SF, Doumbo OK, Duffy PE. Malaria transmission-blocking vaccines Pfs230D1-EPA and Pfs25-EPA in Alhydrogel in healthy Malian adults; a phase 1, randomised, controlled trial. Lancet Infect Dis 2023; 23:1266-1279. [PMID: 37499679 PMCID: PMC10615700 DOI: 10.1016/s1473-3099(23)00276-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Malaria transmission-blocking vaccines target mosquito-stage parasites and will support elimination programmes. Gamete vaccine Pfs230D1-EPA/Alhydrogel induced superior activity to zygote vaccine Pfs25-EPA/Alhydrogel in malaria-naive US adults. Here, we compared these vaccines in malaria-experienced Malians. METHODS We did a pilot safety study then double-blind, block-randomised, comparator-controlled main-phase trial in malaria-intense Bancoumana, Mali. 18-50-year-old healthy non-pregnant, non-breastfeeding consenting adult residents were randomly assigned (1:1:1:1) to receive four doses at months 0, 1, 4·5, and 16·5 of either 47 μg Pfs25, 40 μg Pfs230D1 or comparator (Twinrix or Menactra)-all co-administered with normal saline for blinding-or 47 μg Pfs25 plus 40 μg Pfs230D1 co-administered. We documented safety and tolerability (primary endpoint in the as-treated populations) and immunogenicity (secondary endpoint in the as-treated populations: ELISA, standard-membrane-feeding assay, and mosquito direct skin feed assay). This trial is registered at ClinicalTrials.gov, NCT02334462. FINDINGS Between March 19, and June 2, 2015, we screened 471 individuals. Of 225 enrolled for the pilot and main cohorts, we randomly assigned 25 participants to pilot safety cohort groups of five (20%) to receive a two-dose series of Pfs25-EPA/Alhydrogel (16 μg), Pfs230D1-EPA/Alhydrogel (15 μg) or comparator, followed by Pfs25-EPA/Alhydrogel (16 μg) plus Pfs230D1-EPA/Alhydrogel (15 μg) or comparator plus saline. For the main cohort, we enrolled 200 participants between May 11 and June 2, 2015, to receive a four-dose series of 47 μg Pfs25-EPA/Alhydrogel plus saline (n=50 [25%]; Pfs25), 40 μg Pfs230D1-EPA/Alhydrogel plus saline (n=49 [25%]; Pfs230D1), 47 μg Pfs25-EPA/Alhydrogel plus 40 μg Pfs230D1-EPA/Alhydrogel (n=50 [25%]; Pfs25 plus Pfs230D1), or comparator (Twinrix or Menactra) plus saline (n=51 [25%]). Vaccinations were well tolerated in the pilot safety and main phases. Most vaccinees became seropositive after two Pfs230D1 or three Pfs25 doses; peak titres increased with each dose thereafter (Pfs230D1 geometric mean: 77·8 [95% CI 56·9-106·3], 146·4 [108·3-198·0], and 410·2 [301·6-558·0]; Pfs25 geometric mean 177·7 [130·3-242·4] and 315·7 [209·9-474·6]). Functional activity (mean peak transmission-reducing activity) appeared for Pfs230D1 (74·5% [66·6-82·5]) and Pfs25 plus Pfs230D1 (68·6% [57·3-79·8]), after the third dose and after the fourth dose (88·9% [81·7-96·2] for Pfs230D1 and 85·0% [78·4-91·5] Pfs25 plus Pfs230D1) but not for Pfs25 (58·2% [49·1-67·3] after the third dose and 58·2% [48·5-67·9] after the fourth dose). Pfs230D1 transmission-reducing activity (73·7% [64·1-83·3]) persisted 10 weeks after the fourth dose. Transmission-reducing activity of 80% was estimated at 1659 ELISA units for Pfs25, 218 for Pfs230D1, and 223 for Pfs230D1 plus Pfs25. After 3850 direct skin feed assays, 35 participants (12 Pfs25, eight Pfs230D1, five Pfs25 plus Pfs230D1, and ten comparator) had transmitted parasites at least once. The proportion of positive assays in vaccine groups (Pfs25 33 [3%] of 982 [-0·013 to 0·014], Pfs230D1 22 [2%] of 954 [-0·005 to 0·027], and combination 11 [1%] of 940 [-0·024 to 0·002]) did not differ from that of the comparator (22 [2%] of 974), nor did Pfs230D1 and combination groups differ (-0·024 to 0·001). INTERPRETATION Pfs230D1 but not Pfs25 vaccine induces durable serum functional activity in Malian adults. Direct skin feed assays detect parasite transmission to mosquitoes but increased event rates are needed to assess vaccine effectiveness. FUNDING Intramural Research Program of the National Institute of Allergy and Infectious Diseases and US National Institutes of Health.
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Affiliation(s)
- Issaka Sagara
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Mahamadoun H Assadou
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Mamady Kone
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jennifer L Kwan
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jonathan Fintzi
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kourane Sissoko
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Bourama Kamate
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Yacouba Samake
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Merepen A Guindo
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - M'Bouye Doucoure
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Karamoko Niaré
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Amagana Dolo
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Balla Diarra
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Kelly M Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - David S Jones
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Nicholas J MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - J Patrick Gorres
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Alemush Imeru
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Rathy Mohan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Ismaila Thera
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Fernando Salazar-Miralles
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Junhui Duan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Jillian Neal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Robert D Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Daman Sylla
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Elise M O'Connell
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Jen C C Hume
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Mamadou B Coulibaly
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Charles F Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Sekou F Traore
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Ogobara K Doumbo
- Malaria Research and Training Center, Mali- National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Sciences, Techniques and Technologies of Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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2
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Rausch KM, Barnafo EK, Lambert LE, Muratova O, Gorres JP, Anderson C, Narum DL, Wu Y, Morrison RD, Zaidi I, Duffy PE. Preclinical evaluations of Pfs25-EPA and Pfs230D1-EPA in AS01 for a vaccine to reduce malaria transmission. iScience 2023; 26:107192. [PMID: 37485364 PMCID: PMC10359932 DOI: 10.1016/j.isci.2023.107192] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 02/15/2023] [Accepted: 06/19/2023] [Indexed: 07/25/2023] Open
Abstract
Malaria transmission-blocking vaccine candidates Pfs25-EPA and Pfs230D1-EPA target sexual stage development of Plasmodium falciparum parasites in the mosquito host, thereby reducing mosquito infectivity. When formulated on Alhydrogel, Pfs25-EPA has demonstrated safety and immunogenicity in a phase 1 field trial, while Pfs230D1-EPA has shown superior activity to Pfs25-EPA in a phase 1 US trial and has entered phase 2 field trials. Development continues to enhance immunogenicity of these candidates toward producing a vaccine to reduce malaria transmission (VRMT) with both pre-erythrocytic (i.e., anti-infection) and transmission-blocking components. GSK Adjuvant Systems have demonstrated successful potency in pre-erythrocytic vaccine trials and might offer a common platform for VRMT development. Here, we describe preclinical evaluations of Pfs25-EPA and Pfs230D1-EPA nanoparticles with GSK platforms. Formulations were stable after a series of assessments and induced superior antibody titers and functional activity in CD-1 mice, compared to Alhydrogel formulations of the same antigens.
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Affiliation(s)
- Kelly M. Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Emma K. Barnafo
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Lynn E. Lambert
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - J. Patrick Gorres
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - David L. Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Robert D. Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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3
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MacDonald NJ, Singh K, Reiter K, Nguyen V, Shimp R, Gittis AG, Chen B, Burkhardt M, Zhang B, Wang Z, Herrera R, Moler M, Lee DY, Orr-Gonzalez S, Herrod J, Lambert LE, Rausch KM, Muratova O, Jones DS, Wu Y, Jin AJ, Garboczi DN, Duffy PE, Narum DL. Structural and immunological differences in Plasmodium falciparum sexual stage transmission-blocking vaccines comprised of Pfs25-EPA nanoparticles. NPJ Vaccines 2023; 8:56. [PMID: 37061547 PMCID: PMC10105769 DOI: 10.1038/s41541-023-00655-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 03/29/2023] [Indexed: 04/17/2023] Open
Abstract
Development of a malaria vaccine that blocks transmission of different parasite stages to humans and mosquitoes is considered critical for elimination efforts. A vaccine using Pfs25, a protein on the surface of zygotes and ookinetes, is under investigation as a transmission-blocking vaccine (TBV) that would interrupt parasite passage from mosquitoes to humans. The most extensively studied Pfs25 TBVs use Pichia pastoris-produced recombinant forms of Pfs25, chemically conjugated to a recombinant carrier protein, ExoProtein A (EPA). The recombinant form of Pfs25 first used in humans was identified as Pfs25H, which contained a total of 14 heterologous amino acid residues located at the amino- and carboxyl-termini including a His6 affinity tag. A second recombinant Pfs25, identified as Pfs25M, was produced to remove the heterologous amino acid residues and conjugated to EPA (Pfs25M-EPA). Here, monomeric Pfs25M was characterized biochemically and biophysically for identity, purity, and integrity including protein structure to assess its comparability with Pfs25H. Although the biological activities of Pfs25H and Pfs25M, whether generated by monomeric forms or conjugated nanoparticles, appeared similar, fine-mapping studies with two transmission-blocking monoclonal antibodies detected structural and immunological differences. In addition, evaluation of antisera generated against conjugated Pfs25H or Pfs25M nanoparticles in nonhuman primates identified polyclonal IgG that recognized these structural differences.
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Affiliation(s)
- Nicholas J MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Kavita Singh
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Karine Reiter
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Vu Nguyen
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Richard Shimp
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Apostolos G Gittis
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Beth Chen
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Martin Burkhardt
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20814, USA
| | - Zhixiong Wang
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Mackenzie Moler
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Duck-Yeon Lee
- National Heart, Lung, and Blood Institute, Bethesda, MD, 20814, USA
| | - Sachy Orr-Gonzalez
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Jessica Herrod
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Lynn E Lambert
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Kelly M Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David S Jones
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Albert J Jin
- Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - David N Garboczi
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA.
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4
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Dickey TH, Gupta R, McAleese H, Ouahes T, Orr-Gonzalez S, Ma R, Muratova O, Salinas ND, Hume JCC, Lambert LE, Duffy PE, Tolia NH. Design of a stabilized non-glycosylated Pfs48/45 antigen enables a potent malaria transmission-blocking nanoparticle vaccine. NPJ Vaccines 2023; 8:20. [PMID: 36808125 PMCID: PMC9938515 DOI: 10.1038/s41541-023-00619-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 02/02/2023] [Indexed: 02/19/2023] Open
Abstract
A malaria vaccine that blocks parasite transmission from human to mosquito would be a powerful method of disrupting the parasite lifecycle and reducing the incidence of disease in humans. Pfs48/45 is a promising antigen in development as a transmission blocking vaccine (TBV) against the deadliest malaria parasite Plasmodium falciparum. The third domain of Pfs48/45 (D3) is an established TBV candidate, but production challenges have hampered development. For example, to date, a non-native N-glycan is required to stabilize the domain when produced in eukaryotic systems. Here, we implement a SPEEDesign computational design and in vitro screening pipeline that retains the potent transmission blocking epitope in Pfs48/45 while creating a stabilized non-glycosylated Pfs48/45 D3 antigen with improved characteristics for vaccine manufacture. This antigen can be genetically fused to a self-assembling single-component nanoparticle, resulting in a vaccine that elicits potent transmission-reducing activity in rodents at low doses. The enhanced Pfs48/45 antigen enables many new and powerful approaches to TBV development, and this antigen design method can be broadly applied towards the design of other vaccine antigens and therapeutics without interfering glycans.
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Affiliation(s)
- Thayne H. Dickey
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Richi Gupta
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Holly McAleese
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Tarik Ouahes
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Sachy Orr-Gonzalez
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Rui Ma
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Olga Muratova
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Nichole D. Salinas
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Jen C. C. Hume
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Lynn E. Lambert
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Patrick E. Duffy
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA ,grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
| | - Niraj H. Tolia
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD USA
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5
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Scaria PV, Anderson C, Muratova O, Alani N, Trinh HV, Nadakal ST, Zaidi I, Lambert L, Beck Z, Barnafo EK, Rausch KM, Rowe C, Chen B, Matyas GR, Rao M, Alving CR, Narum DL, Duffy PE. Malaria transmission-blocking conjugate vaccine in ALFQ adjuvant induces durable functional immune responses in rhesus macaques. NPJ Vaccines 2021; 6:148. [PMID: 34887448 PMCID: PMC8660773 DOI: 10.1038/s41541-021-00407-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/03/2021] [Indexed: 12/14/2022] Open
Abstract
Malaria transmission-blocking vaccines candidates based on Pfs25 and Pfs230 have advanced to clinical studies. Exoprotein A (EPA) conjugate of Pfs25 in Alhydrogel® developed functional immunity in humans, with limited durability. Pfs230 conjugated to EPA (Pfs230D1-EPA) with liposomal adjuvant AS01 is currently in clinical trials in Mali. Studies with these conjugates revealed that non-human primates are better than mice to recapitulate the human immunogenicity and functional activity. Here, we evaluated the effect of ALFQ, a liposomal adjuvant consisting of TLR4 agonist and QS21, on the immunogenicity of Pfs25-EPA and Pfs230D1-EPA in Rhesus macaques. Both conjugates generated strong antibody responses and functional activity after two vaccinations though activity declined rapidly. A third vaccination of Pfs230D1-EPA induced functional activity lasting at least 9 months. Antibody avidity increased with each vaccination and correlated strongly with functional activity. IgG subclass analysis showed induction of Th1 and Th2 subclass antibody levels that correlated with activity.
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Affiliation(s)
- Puthupparampil V. Scaria
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Charles Anderson
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Olga Muratova
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Nada Alani
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Hung V. Trinh
- grid.507680.c0000 0001 2230 3166U.S. Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910 USA ,grid.201075.10000 0004 0614 9826Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, MD 20817 USA
| | - Steven T. Nadakal
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Irfan Zaidi
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Lynn Lambert
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Zoltan Beck
- grid.507680.c0000 0001 2230 3166U.S. Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910 USA ,grid.201075.10000 0004 0614 9826Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, MD 20817 USA ,grid.410513.20000 0000 8800 7493Present Address: Pfizer, Vaccine Research and Development, Pearl River, NY USA
| | - Emma K. Barnafo
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Kelly M. Rausch
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Chris Rowe
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Beth Chen
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Gary R. Matyas
- grid.507680.c0000 0001 2230 3166U.S. Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910 USA
| | - Mangala Rao
- grid.507680.c0000 0001 2230 3166U.S. Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910 USA
| | - Carl R. Alving
- grid.507680.c0000 0001 2230 3166U.S. Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910 USA
| | - David L. Narum
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
| | - Patrick E. Duffy
- grid.419681.30000 0001 2164 9667Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, 29 Lincoln Drive, Building 29B, Bethesda, MD 20892-2903 USA
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6
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Faiman R, Krajacich BJ, Graber L, Dao A, Yaro AS, Yossi O, Sanogo ZL, Diallo M, Samaké D, Sylla D, Coulibaly M, Kone S, Goita S, Coulibaly MB, Muratova O, McCormack A, Gonçalves BP, Hume J, Duffy P, Lehmann T. A novel fluorescence and DNA combination for versatile, long-term marking of mosquitoes. Methods Ecol Evol 2021; 12:1008-1016. [PMID: 34249305 PMCID: PMC8252004 DOI: 10.1111/2041-210x.13592] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 02/19/2021] [Indexed: 11/29/2022]
Abstract
Current mark-release-recapture methodologies are limited in their ability to address complex problems in vector biology, such as studying multiple groups overlapping in space and time. Additionally, limited mark retention, reduced post-marking survival and the large effort in marking, collection and recapture all complicate effective insect tracking.We have developed and evaluated a marking method using a fluorescent dye (SmartWater®) combined with synthetic DNA tags to informatively and efficiently mark adult mosquitoes using an airbrush pump and nebulizer. Using a handheld UV flashlight, the fluorescent marking enabled quick and simple initial detection of recaptures in a field-ready and non-destructive approach that when combined with an extraction-free PCR on individual mosquito legs provides potentially unlimited marking information.This marking, first tested in the laboratory with Anopheles gambiae s.l. mosquitoes, did not affect survival (median ages 24-28 days, p-adj > 0.25), oviposition (median eggs/female of 28.8, 32.5, 33.3 for water, green, red dyes, respectively, p-adj > 0.44) or Plasmodium competence (mean oocysts 5.56-10.6, p-adj > 0.95). DNA and fluorescence had 100% retention up to 3 weeks (longest time point tested) with high intensity, indicating marks would persist longer.We describe a novel, simple, no/low-impact and long-lasting marking method that allows separation of multiple insect subpopulations by combining unlimited length and sequence variation in the synthetic DNA tags. This method can be readily deployed in the field for marking multiple groups of mosquitoes or other insects.
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Affiliation(s)
- Roy Faiman
- Laboratory of Malaria and Vector ResearchNIAIDNIHRockvilleMDUSA
| | | | - Leland Graber
- Laboratory of Malaria and Vector ResearchNIAIDNIHRockvilleMDUSA
| | - Adama Dao
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Alpha Seydou Yaro
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Ousmane Yossi
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Zana Lamissa Sanogo
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Moussa Diallo
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Djibril Samaké
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Daman Sylla
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Moribo Coulibaly
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Salif Kone
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Sekou Goita
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Mamadou B. Coulibaly
- Malaria Research and Training Center (MRTC)/Faculty of Medicine, Pharmacy and Odonto‐stomatologyUniversity of Sciences, Techniques and TechnologiesBamakoMali
| | - Olga Muratova
- Laboratory of Malaria Immunology and VaccinologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Ashley McCormack
- Laboratory of Malaria Immunology and VaccinologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Bronner P. Gonçalves
- Laboratory of Malaria Immunology and VaccinologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Jennifer Hume
- Laboratory of Malaria Immunology and VaccinologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Patrick Duffy
- Laboratory of Malaria Immunology and VaccinologyNational Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaMDUSA
| | - Tovi Lehmann
- Laboratory of Malaria and Vector ResearchNIAIDNIHRockvilleMDUSA
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7
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Healy SA, Anderson C, Swihart BJ, Mwakingwe A, Gabriel EE, Decederfelt H, Hobbs CV, Rausch KM, Zhu D, Muratova O, Herrera R, Scaria PV, MacDonald NJ, Lambert LE, Zaidi I, Coelho CH, Renn JP, Wu Y, Narum DL, Duffy PE. Pfs230 yields higher malaria transmission-blocking vaccine activity than Pfs25 in humans but not mice. J Clin Invest 2021; 131:146221. [PMID: 33561016 PMCID: PMC8011888 DOI: 10.1172/jci146221] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/03/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUNDVaccines that block human-to-mosquito Plasmodium transmission are needed for malaria eradication, and clinical trials have targeted zygote antigen Pfs25 for decades. We reported that a Pfs25 protein-protein conjugate vaccine formulated in alum adjuvant induced serum functional activity in both US and Malian adults. However, antibody levels declined rapidly, and transmission-reducing activity required 4 vaccine doses. Functional immunogenicity and durability must be improved before advancing transmission-blocking vaccines further in clinical development. We hypothesized that the prefertilization protein Pfs230 alone or in combination with Pfs25 would improve functional activity.METHODSTransmission-blocking vaccine candidates based on gamete antigen Pfs230 or Pfs25 were conjugated with Exoprotein A, formulated in Alhydrogel, and administered to mice, rhesus macaques, and humans. Antibody levels were measured by ELISA and transmission-reducing activity was assessed by the standard membrane feeding assay.RESULTSPfs25-EPA/Alhydrogel and Pfs230D1-EPA/Alhydrogel induced similar serum functional activity in mice, but Pfs230D1-EPA induced significantly greater activity in rhesus monkeys that was enhanced by complement. In US adults, 2 vaccine doses induced complement-dependent activity in 4 of 5 Pfs230D1-EPA/Alhydrogel recipients but no significant activity in 5 Pfs25-EPA recipients, and combination with Pfs25-EPA did not increase activity over Pfs230D1-EPA alone.CONCLUSIONThe complement-dependent functional immunogenicity of Pfs230D1-EPA represents a significant improvement over Pfs25-EPA in this comparative study. The rhesus model is more predictive of the functional human immune response to Pfs230D1 than is the mouse model.TRIAL REGISTRATIONClinicalTrials.gov NCT02334462.FUNDINGIntramural Research Program of the National Institute of Allergy and Infectious Diseases, National Institutes of Health.
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Affiliation(s)
- Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | | | - Erin E Gabriel
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.,Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Hope Decederfelt
- Pharmacy Department, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | | | | | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, and
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, and
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | | | | | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | | | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, and
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, and
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8
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Coelho CH, Tang WK, Burkhardt M, Galson JD, Muratova O, Salinas ND, Alves e Silva TL, Reiter K, MacDonald NJ, Nguyen V, Herrera R, Shimp R, Narum DL, Byrne-Steele M, Pan W, Hou X, Brown B, Eisenhower M, Han J, Jenkins BJ, Doritchamou JYA, Smelkinson MG, Vega-Rodríguez J, Trück J, Taylor JJ, Sagara I, Healy SA, Renn JP, Tolia NH, Duffy PE. A human monoclonal antibody blocks malaria transmission and defines a highly conserved neutralizing epitope on gametes. Nat Commun 2021; 12:1750. [PMID: 33741942 PMCID: PMC7979743 DOI: 10.1038/s41467-021-21955-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 02/17/2021] [Indexed: 01/31/2023] Open
Abstract
Malaria elimination requires tools that interrupt parasite transmission. Here, we characterize B cell receptor responses among Malian adults vaccinated against the first domain of the cysteine-rich 230 kDa gamete surface protein Pfs230, a key protein in sexual stage development of P. falciparum parasites. Among nine Pfs230 human monoclonal antibodies (mAbs) that we generated, one potently blocks transmission to mosquitoes in a complement-dependent manner and reacts to the gamete surface; the other eight show only low or no blocking activity. The structure of the transmission-blocking mAb in complex with vaccine antigen reveals a large discontinuous conformational epitope, specific to domain 1 of Pfs230 and comprising six structural elements in the protein. The epitope is conserved, suggesting the transmission-blocking mAb is broadly functional. This study provides a rational basis to improve malaria vaccines and develop therapeutic antibodies for malaria elimination.
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Affiliation(s)
- Camila H. Coelho
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Wai Kwan Tang
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Martin Burkhardt
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Jacob D. Galson
- grid.7400.30000 0004 1937 0650Division of Immunology and Children’s Research Center, University Children’s Hospital Zurich, University of Zurich (UZH), Zurich, Switzerland ,Alchemab Therapeutics Ltd, 55-56 Russell Square, London, UK
| | - Olga Muratova
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Nichole D. Salinas
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Thiago Luiz Alves e Silva
- grid.94365.3d0000 0001 2297 5165Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD USA
| | - Karine Reiter
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Nicholas J. MacDonald
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Vu Nguyen
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Raul Herrera
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Richard Shimp
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - David L. Narum
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | | | - Wenjing Pan
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | - Xiaohong Hou
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | | | | | - Jian Han
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | - Bethany J. Jenkins
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Justin Y. A. Doritchamou
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Margery G. Smelkinson
- grid.94365.3d0000 0001 2297 5165Biological Imaging Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Joel Vega-Rodríguez
- grid.94365.3d0000 0001 2297 5165Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD USA
| | - Johannes Trück
- grid.7400.30000 0004 1937 0650Division of Immunology and Children’s Research Center, University Children’s Hospital Zurich, University of Zurich (UZH), Zurich, Switzerland
| | - Justin J. Taylor
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Research Center, Seattle, WA USA
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technology, Bamako, Mali
| | - Sara A. Healy
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Jonathan P. Renn
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Niraj H. Tolia
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Patrick E. Duffy
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA ,grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
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9
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Singh K, Burkhardt M, Nakuchima S, Herrera R, Muratova O, Gittis AG, Kelnhofer E, Reiter K, Smelkinson M, Veltri D, Swihart BJ, Shimp R, Nguyen V, Zhang B, MacDonald NJ, Duffy PE, Garboczi DN, Narum DL. Structure and function of a malaria transmission blocking vaccine targeting Pfs230 and Pfs230-Pfs48/45 proteins. Commun Biol 2020; 3:395. [PMID: 32709983 PMCID: PMC7381611 DOI: 10.1038/s42003-020-01123-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 07/03/2020] [Indexed: 12/21/2022] Open
Abstract
Proteins Pfs230 and Pfs48/45 are Plasmodium falciparum transmission-blocking (TB) vaccine candidates that form a membrane-bound protein complex on gametes. The biological role of Pfs230 or the Pfs230-Pfs48/45 complex remains poorly understood. Here, we present the crystal structure of recombinant Pfs230 domain 1 (Pfs230D1M), a 6-cysteine domain, in complex with the Fab fragment of a TB monoclonal antibody (mAb) 4F12. We observed the arrangement of Pfs230 on the surface of macrogametes differed from that on microgametes, and that Pfs230, with no known membrane anchor, may exist on the membrane surface in the absence of Pfs48/45. 4F12 appears to sterically interfere with Pfs230 function. Combining mAbs against different epitopes of Pfs230D1 or of Pfs230D1 and Pfs48/45, significantly increased TB activity. These studies elucidate a mechanism of action of the Pfs230D1 vaccine, model the functional activity induced by a polyclonal antibody response and support the development of TB vaccines targeting Pfs230D1 and Pfs230D1-Pfs48/45. With the aim to advance the development of a P. falciparum transmission blocking vaccine, Singh et al. determine the crystal structure of Pfs230D1 in complex with the Fab fragment of TB mAb 4F12. They further study the cellular localization of Pfs230 on the surface of sexual stages of parasites and the effect of combining TB mAbs against Pfs230 and Pfs48/45.
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Affiliation(s)
- Kavita Singh
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Martin Burkhardt
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Sofia Nakuchima
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Apostolos G Gittis
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Emily Kelnhofer
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Karine Reiter
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Margery Smelkinson
- Biological Imaging Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4 Memorial Drive, Bethesda, MD, 20814, USA
| | - Daniel Veltri
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Richard Shimp
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Vu Nguyen
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20814, USA
| | - Nicholas J MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David N Garboczi
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA.
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10
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Coelho CH, Gazzinelli-Guimaraes PH, Howard J, Barnafo E, Alani NAH, Muratova O, McCormack A, Kelnhofer E, Urban JF, Narum DL, Anderson C, Langhorne J, Nutman TB, Duffy PE. Chronic helminth infection does not impair immune response to malaria transmission blocking vaccine Pfs230D1-EPA/Alhydrogel® in mice. Vaccine 2019; 37:1038-1045. [PMID: 30685251 PMCID: PMC6382667 DOI: 10.1016/j.vaccine.2019.01.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 12/20/2022]
Abstract
Pfs230 is a candidate malaria transmission blocking vaccine against P. falciparum. Pfs230 vaccine is being tested in areas where malaria and helminth infections are co-endemic. Chronic helminth infection induces a marked increase in systemic Th2 and regulatory cytokine levels in mice. Chronic H. polygyrus bakeri infection does not alter Pfs230 vaccine specific-antibody levels. Functional activity of Pfs230 vaccine was not impaired by chronic helminth infection in mice.
Introduction Malaria transmission blocking vaccines (TBV) are innovative approaches that aim to induce immunity in humans against Plasmodium during mosquito stage, neutralizing the capacity of the infected vectors to transmit malaria. Pfs230D1-EPA/Alhydrogel®, a promising protein-protein conjugate malaria TBV, is currently being tested in human clinical trials in areas where P. falciparum malaria is coendemic with helminth parasites. Helminths are complex metazoans that share the master capacity to downregulate the host immune response towards themselves and also to bystander antigens, including vaccines. However, it is not known whether the activity of a protein-based malaria TBV may be affected by a chronic helminth infection. Methods Using an experimental murine model for a chronic helminth infection (Heligmosomoides polygyrus bakeri - Hpb), we evaluated whether prior infection alters the activity of Pfs230D1-EPA/Alhydrogel® TBV in mice. Results After establishment of a chronic infection, characterized by a marked increase of parasite antigen-specific IgG1, IgA and IgE antibody responses, concomitant with an increase of systemic IL-10, IL-5 and IL-6 levels, the Hpb-infected mice were immunized with Pfs230D1-EPA/Alhydrogel® and the vaccine-specific immune response was compared with that in non-infected immunized mice. TBV immunizations induced an elevated vaccine specific-antibody response, however Pfs230D1 specific-IgG levels were similar between infected and uninfected mice at days 15, 25 and 35 post-vaccination. Absolute numbers of Pfs230D1-activated B cells generated in response to the vaccine were also similar among the vaccinated groups. Finally, vaccine activity assessed by reduction of oocyst number in P. falciparum infected mosquitoes was similar between Hpb-infected and immunized mice with non-infected immunized mice. Conclusion Pfs230D1-EPA/Alhydrogel® efficacy is not impaired by a chronic helminth infection in mice.
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Affiliation(s)
- Camila H Coelho
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | | | - Jennifer Howard
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Emma Barnafo
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Nada A H Alani
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Ashley McCormack
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Emily Kelnhofer
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Joseph F Urban
- US Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomic and Immunology Laboratory, Beltsville, MD, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | | | - Thomas B Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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11
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Sagara I, Healy SA, Assadou MH, Gabriel EE, Kone M, Sissoko K, Tembine I, Guindo MA, Doucoure M, Niaré K, Dolo A, Rausch KM, Narum DL, Jones DL, MacDonald NJ, Zhu D, Mohan R, Muratova O, Baber I, Coulibaly MB, Fay MP, Anderson C, Wu Y, Traore SF, Doumbo OK, Duffy PE. Safety and immunogenicity of Pfs25H-EPA/Alhydrogel, a transmission-blocking vaccine against Plasmodium falciparum: a randomised, double-blind, comparator-controlled, dose-escalation study in healthy Malian adults. Lancet Infect Dis 2018; 18:969-982. [PMID: 30061051 DOI: 10.1016/s1473-3099(18)30344-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/27/2018] [Accepted: 05/15/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Pfs25H-EPA is a protein-protein conjugate transmission-blocking vaccine against Plasmodium falciparum that is safe and induces functional antibodies in malaria-naive individuals. In this field trial, we assessed Pfs25H-EPA/Alhydrogel for safety and functional immunogenicity in Malian adults. METHODS This double-blind, randomised, comparator-controlled, dose-escalation trial in Bancoumana, Mali, was done in two staggered phases, an initial pilot safety assessment and a subsequent main phase. Healthy village residents aged 18-45 years were eligible if they had normal laboratory results (including HIV, hepatitis B, hepatitis C tests) and had not received a previous malaria vaccine or recent immunosuppressive drugs, vaccines, or blood products. Participants in the pilot safety cohort and the main cohort were assigned (1:1) by block randomisation to a study vaccine group. Participants in the pilot safety cohort received two doses of Pfs25H-EPA/Alhydrogel 16 μg or Euvax B (comparator vaccine), and participants in the main cohort received Pfs25H-EPA/Alhydrogel 47 μg or comparator vaccine (Euvax B for the first, second, and third vaccinations and Menactra for the fourth vaccination). Participants and investigators were masked to group assignment, and randomisation codes in sealed envelopes held by a site pharmacist. Vials with study drug for injection were covered by opaque tape and labelled with a study identification number. Group assignments were unmasked at final study visit. The primary outcomes were safety and tolerability for all vaccinees. The secondary outcome measure was immunogenicity 14 days after vaccination in the per-protocol population, as confirmed by the presence of antibodies against Pfs25H measured by ELISA IgG and antibody functionality assessed by standard membrane feeding assays and by direct skin feeding assays. This trial is registered with ClinicalTrials.gov, number NCT01867463. FINDINGS Between May 15, and Jun 16, 2013, 230 individuals were screened for eligibility. 20 individuals were enrolled in the pilot safety cohort; ten participants were assigned to receive Pfs25H-EPA/Alhydrogel 16 μg, and ten participants were assigned to receive comparator vaccine. 100 individuals were enrolled in the main cohort; 50 participants were assigned to receive Pfs25H-EPA/Alhydrogel 47 μg, and 50 participants were assigned to receive comparator vaccine. Compared with comparator vaccinees, Pfs25H vaccinees had more solicited adverse events (137 events vs 86 events; p=0·022) and treatment-related adverse events (191 events vs 126 events, p=0·034), but the number of other adverse events did not differ between study vaccine groups (792 vs 683). Pfs25H antibody titres increased with each dose, with a peak geometric mean of 422·3 ELISA units (95% CI 290-615) after the fourth dose, but decreased relatively rapidly thereafter, with a half-life of 42 days for anti-Pfs25H and 59 days for anti-EPA (median ratio of titres at day 600 to peak, 0·19 for anti-Pfs25H vs 0·29 for anti-EPA; p=0·009). Serum transmission-reducing activity was greater for Pfs25H than for comparator vaccine after the fourth vaccine dose (p<0·001) but not after the third dose (p=0·09). Repeated direct skin feeds were well tolerated, but the number of participants who infected at least one mosquito did not differ between Pfs25H and comparator vaccinees after the fourth dose (p=1, conditional exact). INTERPRETATION Pfs25H-EPA/Alhydrogel was well tolerated and induced significant serum activity by standard membrane feeding assays but transmission blocking activity was not confirmed by weekly direct skin feed. This activity required four doses, and titres decreased rapidly after the fourth dose. Alternative antigens or combinations should be assessed to improve activity. FUNDING Division of Intramural Research, National Institute of Allergy and Infectious Diseases.
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Affiliation(s)
- Issaka Sagara
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Mahamadoun H Assadou
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Erin E Gabriel
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Mamady Kone
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Kourane Sissoko
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Intimbeye Tembine
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Merepen A Guindo
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - M'Bouye Doucoure
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Karamoko Niaré
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Amagana Dolo
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Kelly M Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - David L Jones
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Nicholas J MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Rathy Mohan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Ibrahima Baber
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Mamadou B Coulibaly
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Michael P Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Sekou F Traore
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Ogobara K Doumbo
- Malaria Research and Training Center, Mali-National Institute of Allergy and Infectious Diseases International Center for Excellence in Research, University of Science, Techniques and Technologies of Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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12
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Hou X, Byrne-Steele ML, Pan W, Brown B, Sanders M, Eisenhower M, Coelho C, Hurtado PG, Doritchamou Y, Highsmith K, Taylor JJ, Schwartz A, Morrison B, Muratova O, Sagara I, Doumbo O, Anderson C, Fried M, Duffy PE, Han J. Identification of paired heavy and light chains from single B-cells from immunized Malian adults with rapid functional confirmation using iPair-BCR™, NGS, and iScreen™. The Journal of Immunology 2018. [DOI: 10.4049/jimmunol.200.supp.174.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Information about the cognate pairing of TCR alpha-beta chains and BCR IgH and IgKL chains encoded by individual T and B cells is key to understanding adaptive immune responses and developing therapeutic applications. We have previously reported the development of a sensitive technology that allows the amplification and identification of the paired human TCR alpha and beta chains from single T cells, termed iPair-TCR. Here, we report the extension of this technology to identify paired human BCR IgH and IgKL chains from antigen-specific single B cells. In this proof of concept study, we identified paired-VDJ-receptors from antigen-specific B-cells from nine Pfs230-EPA immunized Malian adults using the iPair-BCR method. Next, we developed a method to rapidly generate Fab fragments and demonstrate the binding of several of these single cell targets to the original Pfs230 antigen. Single cells of interest were identified based upon their repeated frequency on the plate, which indicates a clonal selection. The corresponding heavy and light chains were PCR amplified from selected wells. Using overlap extension PCR, all necessary elements for in vitro transcription and translation and either the CH1 or C-kappa-domain were added to both the 5′ and 3′ ends of the single cell VDJ. After in vitro transcription and translation, four out of five tested Fab fragments demonstrated binding through a colorimetric ELISA assay. The overall process after VDJ identification can be performed in under a week indicating the utility of our technology for rapid identification of antigen-specific BCRs and functional binding characteristics.
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13
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An SJ, Scaria PV, Chen B, Barnafo E, Muratova O, Anderson C, Lambert L, Chae MH, Yang JS, Duffy PE. Development of a bivalent conjugate vaccine candidate against malaria transmission and typhoid fever. Vaccine 2018; 36:2978-2984. [PMID: 29681410 DOI: 10.1016/j.vaccine.2018.04.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 01/24/2023]
Abstract
Immune responses to poorly immunogenic antigens, such as polysaccharides, can be enhanced by conjugation to carriers. Our previous studies indicate that conjugation to Vi polysaccharide of Salmonella Typhi may also enhance immunogenicity of some protein carriers. We therefore explored the possibility of generating a bivalent vaccine against Plasmodium falciparum malaria and typhoid fever, which are co-endemic in many parts of the world, by conjugating Vi polysaccharide, an approved antigen in typhoid vaccine, to Pfs25, a malaria transmission blocking vaccine antigen in clinical trials. Vi-Pfs25 conjugates induced strong immune responses against both Vi and Pfs25 in mice, whereas the unconjugated antigens are poorly immunogenic. Functional assays of immune sera revealed potent transmission blocking activity mediated by anti-Pfs25 antibody and serum bactericidal activity due to anti-Vi antibody. Pfs25 conjugation to Vi modified the IgG isotype distribution of antisera, inducing a Th2 polarized immune response against Vi antigen. This conjugate may be further developed as a bivalent vaccine to concurrently target malaria and typhoid fever.
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Affiliation(s)
- So Jung An
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; International Vaccine Institute, SNU Research Park, 1 Gwanak-ro, Gwanak-gu, 151-742 Seoul, Republic of Korea
| | - Puthupparampil V Scaria
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Beth Chen
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Emma Barnafo
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Lynn Lambert
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Myung Hwa Chae
- International Vaccine Institute, SNU Research Park, 1 Gwanak-ro, Gwanak-gu, 151-742 Seoul, Republic of Korea
| | - Jae Seung Yang
- International Vaccine Institute, SNU Research Park, 1 Gwanak-ro, Gwanak-gu, 151-742 Seoul, Republic of Korea
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA.
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14
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Talaat KR, Ellis RD, Hurd J, Hentrich A, Gabriel E, Hynes NA, Rausch KM, Zhu D, Muratova O, Herrera R, Anderson C, Jones D, Aebig J, Brockley S, MacDonald NJ, Wang X, Fay MP, Healy SA, Durbin AP, Narum DL, Wu Y, Duffy PE. Safety and Immunogenicity of Pfs25-EPA/Alhydrogel®, a Transmission Blocking Vaccine against Plasmodium falciparum: An Open Label Study in Malaria Naïve Adults. PLoS One 2016; 11:e0163144. [PMID: 27749907 PMCID: PMC5066979 DOI: 10.1371/journal.pone.0163144] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 09/01/2016] [Indexed: 12/31/2022] Open
Abstract
Transmission-blocking vaccines (TBVs) that target sexual stage parasite development could be an integral part of measures for malaria elimination. Pfs25 is a leading TBV candidate, and previous studies conducted in animals demonstrated an improvement of its functional immunogenicity after conjugation to EPA, a recombinant, detoxified ExoProtein A from Pseudomonas aeruginosa. In this report, we describe results of an open-label, dose-escalating Phase 1 trial to assess the safety and immunogenicity of Pfs25-EPA conjugates formulated with Alhydrogel®. Thirty malaria-naïve healthy adults received up to four doses of the conjugate vaccine, with 8, 16, or 47 μg of conjugated Pfs25 mass, at 0, 2, 4, and 10 months. Vaccinations were generally well tolerated. The majority of solicited adverse events were mild in severity with pain at the injection site the most common complaint. Anemia was the most common laboratory abnormality, but was considered possibly related to the study in only a minority of cases. No vaccine-related serious adverse events occurred. The peak geometric mean anti-Pfs25 antibody level in the highest dose group was 88 (95% CI 53, 147) μg/mL two weeks after the 4th vaccination, and declined to near baseline one year later. Antibody avidity increased over successive vaccinations. Transmission blocking activity demonstrated in a standard membrane feeding assay (SMFA) also increased from the second to the third dose, and correlated with antibody titer and, after the final dose, with antibody avidity. These results support the further evaluation of Pfs25-EPA/Alhydrogel® in a malaria-endemic population.
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Affiliation(s)
- Kawsar R. Talaat
- Center For Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Ruth D. Ellis
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Janet Hurd
- Center For Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Autumn Hentrich
- Center For Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Erin Gabriel
- Biostatistical Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Noreen A. Hynes
- Center For Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kelly M. Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - David Jones
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Joan Aebig
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Sarah Brockley
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Nicholas J. MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Xiaowei Wang
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Michael P. Fay
- Biostatistical Research Branch, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Sara A. Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Anna P. Durbin
- Center For Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - David L. Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail:
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
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15
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MacDonald NJ, Nguyen V, Shimp R, Reiter K, Herrera R, Burkhardt M, Muratova O, Kumar K, Aebig J, Rausch K, Lambert L, Dawson N, Sattabongkot J, Ambroggio X, Duffy PE, Wu Y, Narum DL. Structural and Immunological Characterization of Recombinant 6-Cysteine Domains of the Plasmodium falciparum Sexual Stage Protein Pfs230. J Biol Chem 2016; 291:19913-22. [PMID: 27432885 DOI: 10.1074/jbc.m116.732305] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 01/21/2023] Open
Abstract
Development of a Plasmodium falciparum (Pf) transmission blocking vaccine (TBV) has the potential to significantly impact malaria control. Antibodies elicited against sexual stage proteins in the human bloodstream are taken up with the blood meal of the mosquitoes and inactivate parasite development in the mosquito. In a phase 1 trial, a leading TBV identified as Pfs25-EPA/Alhydrogel® appeared safe and immunogenic, however, the level of Pfs25-specific antibodies were likely too low for an effective vaccine. Pfs230, a 230-kDa sexual stage protein expressed in gametocytes is an alternative vaccine candidate. A unique 6-cysteine-rich domain structure within Pfs230 have thwarted its recombinant expression and characterization for clinical evaluation for nearly a quarter of a century. Here, we report on the identification, biochemical, biophysical, and immunological characterization of recombinant Pfs230 domains. Rabbit antibodies generated against recombinant Pfs230 domains blocked mosquito transmission of a laboratory strain and two field isolates using an ex vivo assay. A planned clinical trial of the Pfs230 vaccine is a significant step toward the potential development of a transmission blocking vaccine to eliminate malaria.
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Affiliation(s)
- Nicholas J MacDonald
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Vu Nguyen
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Richard Shimp
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Karine Reiter
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Raul Herrera
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Martin Burkhardt
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Olga Muratova
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Krishan Kumar
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Joan Aebig
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Kelly Rausch
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Lynn Lambert
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Nikiah Dawson
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Jetsumon Sattabongkot
- the Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400 Thailand, and
| | | | - Patrick E Duffy
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - Yimin Wu
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852
| | - David L Narum
- From the Laboratory of Malaria Immunology and Vaccinology, NIAID, National Institutes of Health, Rockville, Maryland 20852,
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16
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Murphy JR, Weiss WR, Fryauff D, Dowler M, Savransky T, Stoyanov C, Muratova O, Lambert L, Orr-Gonzalez S, Zeleski KL, Hinderer J, Fay MP, Joshi G, Gwadz RW, Richie TL, Villasante EF, Richardson JH, Duffy PE, Chen J. Using infective mosquitoes to challenge monkeys with Plasmodium knowlesi in malaria vaccine studies. Malar J 2014; 13:215. [PMID: 24893777 PMCID: PMC4070636 DOI: 10.1186/1475-2875-13-215] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 03/03/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND When rhesus monkeys (Macaca mulatta) are used to test malaria vaccines, animals are often challenged by the intravenous injection of sporozoites. However, natural exposure to malaria comes via mosquito bite, and antibodies can neutralize sporozoites as they traverse the skin. Thus, intravenous injection may not fairly assess humoral immunity from anti-sporozoite malaria vaccines. To better assess malaria vaccines in rhesus, a method to challenge large numbers of monkeys by mosquito bite was developed. METHODS Several species and strains of mosquitoes were tested for their ability to produce Plasmodium knowlesi sporozoites. Donor monkey parasitaemia effects on oocyst and sporozoite numbers and mosquito mortality were documented. Methylparaben added to mosquito feed was tested to improve mosquito survival. To determine the number of bites needed to infect a monkey, animals were exposed to various numbers of P. knowlesi-infected mosquitoes. Finally, P. knowlesi-infected mosquitoes were used to challenge 17 monkeys in a malaria vaccine trial, and the effect of number of infectious bites on monkey parasitaemia was documented. RESULTS Anopheles dirus, Anopheles crascens, and Anopheles dirus X (a cross between the two species) produced large numbers of P. knowlesi sporozoites. Mosquito survival to day 14, when sporozoites fill the salivary glands, averaged only 32% when donor monkeys had a parasitaemia above 2%. However, when donor monkey parasitaemia was below 2%, mosquitoes survived twice as well and contained ample sporozoites in their salivary glands. Adding methylparaben to sugar solutions did not improve survival of infected mosquitoes. Plasmodium knowlesi was very infectious, with all monkeys developing blood stage infections if one or more infected mosquitoes successfully fed. There was also a dose-response, with monkeys that received higher numbers of infected mosquito bites developing malaria sooner. CONCLUSIONS Anopheles dirus, An. crascens and a cross between these two species all were excellent vectors for P. knowlesi. High donor monkey parasitaemia was associated with poor mosquito survival. A single infected mosquito bite is likely sufficient to infect a monkey with P. knowlesi. It is possible to efficiently challenge large groups of monkeys by mosquito bite, which will be useful for P. knowlesi vaccine studies.
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Knöckel J, Molina-Cruz A, Fischer E, Muratova O, Haile A, Barillas-Mury C, Miller LH. An impossible journey? The development of Plasmodium falciparum NF54 in Culex quinquefasciatus. PLoS One 2013; 8:e63387. [PMID: 23658824 PMCID: PMC3643899 DOI: 10.1371/journal.pone.0063387] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/03/2013] [Indexed: 11/19/2022] Open
Abstract
Although Anopheles mosquitoes are the vectors for human Plasmodium spp., there are also other mosquito species-among them culicines (Culex spp., Aedes spp.)-present in malaria-endemic areas. Culicine mosquitoes transmit arboviruses and filarial worms to humans and are vectors for avian Plasmodium spp., but have never been observed to transmit human Plasmodium spp. When ingested by a culicine mosquito, parasites could either face an environment that does not allow development due to biologic incompatibility or be actively killed by the mosquito's immune system. In the latter case, the molecular mechanism of killing must be sufficiently powerful that Plasmodium is not able to overcome it. To investigate how human malaria parasites develop in culicine mosquitoes, we infected Culex quinquefasciatus with Plasmodium falciparum NF54 and monitored development of parasites in the blood bolus and midgut epithelium at different time points. Our results reveal that ookinetes develop in the midgut lumen of C. quinquefasciatus in slightly lower numbers than in Anopheles gambiae G3. After 30 hours, parasites have invaded the midgut and can be observed on the basal side of the midgut epithelium by confocal and transmission electron microscopy. Very few of the parasites in C. quinquefasciatus are alive, most of them are lysed. Eight days after the mosquito's blood meal, no oocysts can be found in C. quinquefasciatus. Our results suggest that the mosquito immune system could be involved in parasite killing early in development after ookinetes have crossed the midgut epithelium and come in contact with the mosquito hemolymph.
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Affiliation(s)
- Julia Knöckel
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Alvaro Molina-Cruz
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Elizabeth Fischer
- Electron Microscopy Unit, Research Technologies Branch, Rocky Mountain Laboratories, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Ashley Haile
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Louis H. Miller
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
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18
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Hobbs CV, Tanaka TQ, Muratova O, Van Vliet J, Borkowsky W, Williamson KC, Duffy PE. HIV treatments have malaria gametocyte killing and transmission blocking activity. J Infect Dis 2013; 208:139-48. [PMID: 23539746 DOI: 10.1093/infdis/jit132] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Millions of individuals being treated for human immunodeficiency virus (HIV) live in malaria-endemic areas, but the effects of these treatments on malaria transmission are unknown. While drugs like HIV protease inhibitors (PIs) and trimethoprim-sulfamethoxazole (TMP-SMX) have known activity against parasites during liver or asexual blood stages, their effects on transmission stages require further study. METHODS The HIV PIs lopinavir and saquinavir, the nonnucleoside reverse-transcriptase inhibitor nevirapine, and the antibiotic TMP-SMX were assessed for activity against Plasmodium falciparum transmission stages. The alamarBlue assay was used to determine the effects of drugs on gametocyte viability, and exflagellation was assessed to determine the effects of drugs on gametocyte maturation. The effects of drug on transmission were assessed by calculating the mosquito oocyst count as a marker for infectivity, using standard membrane feeding assays. RESULTS Lopinavir and saquinavir have gametocytocidal and transmission blocking activities at or approaching clinically relevant treatment levels, while nevirapine does not. TMP-SMX is not gametocytocidal, but at prophylactic levels it blocks transmission. CONCLUSIONS Specific HIV treatments have gametocyte killing and transmission-blocking effects. Clinical studies are warranted to evaluate these findings and their potential impact on eradication efforts.
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Affiliation(s)
- Charlotte V Hobbs
- Laboratory of Malaria Vaccinology and Immunology, NIH/NIAID, 12735 Twinbrook Pkwy, Rockville, MD 20852, USA.
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Musivchuk K, Mett V, Casta L, Farrance CE, Jones RM, Chichester JA, Jaje J, Manceva SD, Shamloul M, Rhee A, Roeffen W, Sauerwein RW, Muratova O, Wu Y, Duffy P, Yusibov V. Plant-produced transmission blocking Plasmodium falciparum Pfs25 subunit and VLP based vaccine candidates. Malar J 2012. [PMCID: PMC3472220 DOI: 10.1186/1475-2875-11-s1-o51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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20
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Farrance CE, Chichester JA, Musiychuk K, Shamloul M, Rhee A, Manceva SD, Jones RM, Mamedov T, Sharma S, Mett V, Streatfield SJ, Roeffen W, van de Vegte-Bolmer M, Sauerwein RW, Wu Y, Muratova O, Miller L, Duffy P, Sinden R, Yusibov V. Antibodies to plant-produced Plasmodium falciparum sexual stage protein Pfs25 exhibit transmission blocking activity. Hum Vaccin 2011; 7 Suppl:191-8. [PMID: 21266847 DOI: 10.4161/hv.7.0.14588] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Malaria is a serious and sometimes fatal mosquito-borne disease caused by a protozoan parasite. Each year, it is estimated that over one million people are killed by malaria, yet the disease is preventable and treatable. Developing vaccines against the parasite is a critical component in the fight against malaria and these vaccines can target different stages of the pathogen's life cycle. We are targeting sexual stage proteins of P. falciparum which are found on the surface of the parasite reproductive cells present in the mosquito gut. Antibodies against these proteins block the progression of the parasite's life cycle in the mosquito, and thus block transmission to the next human host. Transmission blocking vaccines are essential to the malaria eradication program to ease the disease burden at the population level. We have successfully produced multiple versions of the Pfs25 antigen in a plant virus-based transient expression system and have evaluated these vaccine candidates in an animal model. The targets are expressed in plants at a high level, are soluble and most importantly, generate strong transmission blocking activity as determined by a standard membrane feeding assay. These data demonstrate the feasibility of expressing Plasmodium antigens in a plant-based system for the economic production of a transmission blocking vaccine against malaria.
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21
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Wu Y, Ellis RD, Shaffer D, Fontes E, Malkin EM, Mahanty S, Fay MP, Narum D, Rausch K, Miles AP, Aebig J, Orcutt A, Muratova O, Song G, Lambert L, Zhu D, Miura K, Long C, Saul A, Miller LH, Durbin AP. Phase 1 trial of malaria transmission blocking vaccine candidates Pfs25 and Pvs25 formulated with montanide ISA 51. PLoS One 2008; 3:e2636. [PMID: 18612426 PMCID: PMC2440546 DOI: 10.1371/journal.pone.0002636] [Citation(s) in RCA: 294] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 06/04/2008] [Indexed: 11/18/2022] Open
Abstract
Background Pfs25 and Pvs25, surface proteins of mosquito stage of the malaria parasites P. falciparum and P. vivax, respectively, are leading candidates for vaccines preventing malaria transmission by mosquitoes. This single blinded, dose escalating, controlled Phase 1 study assessed the safety and immunogenicity of recombinant Pfs25 and Pvs25 formulated with Montanide ISA 51, a water-in-oil emulsion. Methodology/Principal Findings The trial was conducted at The Johns Hopkins Center for Immunization Research, Washington DC, USA, between May 16, 2005–April 30, 2007. The trial was designed to enroll 72 healthy male and non-pregnant female volunteers into 1 group to receive adjuvant control and 6 groups to receive escalating doses of the vaccines. Due to unexpected reactogenicity, the vaccination was halted and only 36 volunteers were enrolled into 4 groups: 3 groups of 10 volunteers each were immunized with 5 µg of Pfs25/ISA 51, 5 µg of Pvs25/ISA 51, or 20 µg of Pvs25/ISA 51, respectively. A fourth group of 6 volunteers received adjuvant control (PBS/ISA 51). Frequent local reactogenicity was observed. Systemic adverse events included two cases of erythema nodosum considered to be probably related to the combination of the antigen and the adjuvant. Significant antibody responses were detected in volunteers who completed the lowest scheduled doses of Pfs25/ISA 51. Serum anti-Pfs25 levels correlated with transmission blocking activity. Conclusion/Significance It is feasible to induce transmission blocking immunity in humans using the Pfs25/ISA 51 vaccine, but these vaccines are unexpectedly reactogenic for further development. This is the first report that the formulation is associated with systemic adverse events including erythema nodosum. Trial Registration ClinicalTrials.gov NCT00295581
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MESH Headings
- Adolescent
- Adult
- Animals
- Antigens, Protozoan/chemistry
- Antigens, Protozoan/immunology
- Antigens, Surface/chemistry
- Antigens, Surface/immunology
- Disease Transmission, Infectious
- Female
- Humans
- Malaria Vaccines/adverse effects
- Malaria Vaccines/chemistry
- Malaria Vaccines/immunology
- Malaria, Falciparum/prevention & control
- Malaria, Falciparum/transmission
- Malaria, Vivax/prevention & control
- Malaria, Vivax/transmission
- Male
- Mannitol/administration & dosage
- Mannitol/analogs & derivatives
- Mannitol/chemistry
- Middle Aged
- Oleic Acids/administration & dosage
- Oleic Acids/chemistry
- Plasmodium falciparum/immunology
- Plasmodium vivax/immunology
- Protozoan Proteins/adverse effects
- Protozoan Proteins/chemistry
- Protozoan Proteins/immunology
- Recombinant Proteins/adverse effects
- Recombinant Proteins/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/chemistry
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Affiliation(s)
- Yimin Wu
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
- * E-mail: (YW); (AD)
| | - Ruth D. Ellis
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Donna Shaffer
- Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Erica Fontes
- Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Elissa M. Malkin
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Siddhartha Mahanty
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Michael P. Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - David Narum
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Kelly Rausch
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Aaron P. Miles
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Joan Aebig
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Andrew Orcutt
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Olga Muratova
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Guanhong Song
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Lynn Lambert
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Daming Zhu
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Kazutoyo Miura
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Carole Long
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Allan Saul
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Louis H. Miller
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, Rockville, Maryland, United States of America
| | - Anna P. Durbin
- Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail: (YW); (AD)
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22
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Qian F, Rausch KM, Muratova O, Zhou H, Song G, Diouf A, Lambert L, Narum DL, Wu Y, Saul A, Miller LH, Long CA, Mullen GED. Addition of CpG ODN to recombinant Pseudomonas aeruginosa ExoProtein A conjugates of AMA1 and Pfs25 greatly increases the number of responders. Vaccine 2008; 26:2521-7. [PMID: 18423804 PMCID: PMC2426823 DOI: 10.1016/j.vaccine.2008.03.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 03/03/2008] [Accepted: 03/07/2008] [Indexed: 11/22/2022]
Abstract
Both the blood-stage protein apical membrane antigen 1 (AMA1) and the 25-kDa sexual-stage protein (Pfs25) of Plasmodium falciparum are two leading candidates in malarial vaccine development. We have previously demonstrated that conjugation of these malarial antigens to recombinant Pseudomonas aeruginosa ExoProtein A (rEPA) significantly increased the mean-specific functional antibody responses in mice; however, some mice responded poorly and were unable to demonstrate a functional response. We hypothesized that the immunogenicities of these two malarial antigens could be further enhanced by the inclusion of a CpG oligodeoxynucleotide in the formulation. Mice were immunized with either rEPA-conjugated or unconjugated AMA1 and Pfs25 formulated on Alhydrogel with or without the addition of CPG 7909. Mice received the formulations on days 0 and 28, and mouse sera were collected on day 42. ELISA analyses on these sera showed that the addition of CPG 7909 to AMA1-rEPA and Pfs25-rEPA formulated on Alhydrogel induced significantly higher mean antibody titers than the formulations without CPG 7909, and led to a mixed Th1/Th2 response as demonstrated by the production of mouse IgG1 and IgG2a subclasses. The presence of CPG 7909 in the formulations of both conjugated antigens greatly increased the proportion of responders with antibody titers sufficient to inhibit blood-stage parasite growth in vitro or block transmission of sexual-stage parasites to mosquitoes. The results obtained in this study indicate the potential use of a combination strategy to increase the number of responders to malarial antigens in humans.
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Affiliation(s)
- Feng Qian
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Kelly M. Rausch
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Olga Muratova
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Hong Zhou
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Guanhong Song
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Ababacar Diouf
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Lynn Lambert
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - David L. Narum
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Yimin Wu
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Allan Saul
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Louis H. Miller
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Carole A. Long
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
| | - Gregory E. D. Mullen
- Malaria Vaccine Development Branch, National Institutes of Health, Rockville, MD 20852, USA
- * Corresponding author. Present mailing address: Division of Imaging Sciences, King’s College London, The Rayne Institute, 4th Floor, Lambeth Wing, St. Thomas’ Hospital, London, SE1 7EH Tel: + 44 20 7188 5440, fax: +44 20 7188 5442. E-mail address: (G.E.D. Mullen)
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23
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Dinglasan RR, Kalume DE, Kanzok SM, Ghosh AK, Muratova O, Pandey A, Jacobs-Lorena M. Disruption of Plasmodium falciparum development by antibodies against a conserved mosquito midgut antigen. Proc Natl Acad Sci U S A 2007; 104:13461-6. [PMID: 17673553 PMCID: PMC1948931 DOI: 10.1073/pnas.0702239104] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Malaria parasites must undergo development within mosquitoes to be transmitted to a new host. Antivector transmission-blocking vaccines inhibit parasite development by preventing ookinete interaction with mosquito midgut ligands. Therefore, the discovery of novel midgut antigen targets is paramount. Jacalin (a lectin) inhibits ookinete attachment by masking glycan ligands on midgut epithelial surface glycoproteins. However, the identities of these midgut glycoproteins have remained unknown. Here we report on the molecular characterization of an Anopheles gambiae aminopeptidase N (AgAPN1) as the predominant jacalin target on the mosquito midgut luminal surface and provide evidence for its role in ookinete invasion. alpha-AgAPN1 IgG strongly inhibited both Plasmodium berghei and Plasmodium falciparum development in different mosquito species, implying that AgAPN1 has a conserved role in ookinete invasion of the midgut. Molecules targeting single midgut antigens seldom achieve complete abrogation of parasite development. However, the combined blocking activity of alpha-AgAPN1 IgG and an unrelated inhibitory peptide, SM1, against P. berghei was incomplete. We also found that SM1 can block only P. berghei, whereas alpha-AgAPN1 IgG can block both parasite species significantly. Therefore, we hypothesize that ookinetes can evade inhibition by two potent transmission-blocking molecules, presumably through the use of other ligands, and that this process further partitions murine from human parasite midgut invasion models. These results advance our understanding of malaria parasite-mosquito host interactions and guide in the design of transmission-blocking vaccines.
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Affiliation(s)
- Rhoel R. Dinglasan
- *Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205
- To whom correspondence may be addressed. E-mail: or
| | - Dario E. Kalume
- Institute of Genetic Medicine, Johns Hopkins School of Medicine, 733 North Broadway, Baltimore, MD 21205; and
| | - Stefan M. Kanzok
- *Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205
| | - Anil K. Ghosh
- *Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205
| | - Olga Muratova
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5640 Fishers Lane, Rockville, MD 20852
| | - Akhilesh Pandey
- Institute of Genetic Medicine, Johns Hopkins School of Medicine, 733 North Broadway, Baltimore, MD 21205; and
| | - Marcelo Jacobs-Lorena
- *Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205
- To whom correspondence may be addressed. E-mail: or
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24
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Qian F, Wu Y, Muratova O, Zhou H, Dobrescu G, Duggan P, Lynn L, Song G, Zhang Y, Reiter K, MacDonald N, Narum DL, Long CA, Miller LH, Saul A, Mullen GED. Conjugating recombinant proteins to Pseudomonas aeruginosa ExoProtein A: a strategy for enhancing immunogenicity of malaria vaccine candidates. Vaccine 2007; 25:3923-33. [PMID: 17428587 PMCID: PMC1940062 DOI: 10.1016/j.vaccine.2007.02.073] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Revised: 02/15/2007] [Accepted: 02/20/2007] [Indexed: 10/23/2022]
Abstract
Conjugation of polysaccharides to carrier proteins has been a successful approach for producing safe and effective vaccines. In an attempt to increase the immunogenicity of two malarial vaccine candidate proteins of Plasmodium falciparum, apical membrane antigen 1 (AMA1) to a blood stage vaccine candidate and surface protein 25 (Pfs25) a mosquito stage vaccine candidate, were each independently chemically conjugated to the mutant, nontoxic Pseudomonas aeruginosa ExoProtein A (rEPA). AMA1 is a large (66kD) relatively good immunogen in mice; Pfs25 is a poorly immunogenic protein when presented on alum to mice. Mice were immunized on days 0 and 28 with AMA1- or Pfs25-rEPA conjugates or unconjugated AMA1 or Pfs25, all formulated on Alhydrogel. Remarkably, sera from mice 14 days after the second immunization with Pfs25-rEPA conjugates displayed over a 1000-fold higher antibody titers as compared to unconjugated Pfs25. In contrast, AMA1 conjugated under the same conditions induced only a three-fold increase in antibody titers. When tested for functional activity, antibodies elicited by the AMA1-rEPA inhibited invasion of erythrocytes by blood-stage parasites and antibodies elicited by the Pfs25-rEPA conjugates blocked the development of the sexual stage parasites in the mosquito midgut. These results demonstrate that conjugation to rEPA induces a marked improvement in the antibody titer in mice for the poor immunogen (Pfs25) and for the larger protein (AMA1). These conjugates now need to be tested in humans to determine if mice are predictive of the response in humans.
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Affiliation(s)
- Feng Qian
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5640 Fishers Lane, Rockville, MD 20852, USA
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25
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Malkin E, Long CA, Stowers AW, Zou L, Singh S, MacDonald NJ, Narum DL, Miles AP, Orcutt AC, Muratova O, Moretz SE, Zhou H, Diouf A, Fay M, Tierney E, Leese P, Mahanty S, Miller LH, Saul A, Martin LB. Phase 1 study of two merozoite surface protein 1 (MSP1(42)) vaccines for Plasmodium falciparum malaria. PLoS Clin Trials 2007; 2:e12. [PMID: 17415408 PMCID: PMC1847697 DOI: 10.1371/journal.pctr.0020012] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 02/07/2007] [Indexed: 11/19/2022]
Abstract
Objectives: To assess the safety and immunogenicity of two vaccines, MSP142-FVO/Alhydrogel and MSP142-3D7/Alhydrogel, targeting blood-stage Plasmodium falciparum parasites. Design: A Phase 1 open-label, dose-escalating study. Setting: Quintiles Phase 1 Services, Lenexa, Kansas between July 2004 and November 2005. Participants: Sixty healthy malaria-naïve volunteers 18–48 y of age. Interventions: The C-terminal 42-kDa region of merozoite surface protein 1 (MSP142) corresponding to the two allelic forms present in FVO and 3D7 P. falciparum lines were expressed in Escherichia coli, refolded, purified, and formulated on Alhydrogel (aluminum hydroxide). For each vaccine, volunteers in each of three dose cohorts (5, 20, and 80 μg) were vaccinated at 0, 28, and 180 d. Volunteers were followed for 1 y. Outcome Measures: The safety of MSP142-FVO/Alhydrogel and MSP142-3D7/Alhydrogel was assessed. The antibody response to each vaccine was measured by reactivity to homologous and heterologous MSP142, MSP119, and MSP133 recombinant proteins and recognition of FVO and 3D7 parasites. Results: Anti-MSP142 antibodies were detected by ELISA in 20/27 (74%) and 22/27 (81%) volunteers receiving three vaccinations of MSP142-FVO/Alhydrogel or MSP142-3D7/Alhydrogel, respectively. Regardless of the vaccine, the antibodies were cross-reactive to both MSP142-FVO and MSP142-3D7 proteins. The majority of the antibody response targeted the C-terminal 19-kDa domain of MSP142, although low-level antibodies to the N-terminal 33-kDa domain of MSP142 were also detected. Immunofluorescence microscopy of sera from the volunteers demonstrated reactivity with both FVO and 3D7 P. falciparum schizonts and free merozoites. Minimal in vitro growth inhibition of FVO or 3D7 parasites by purified IgG from the sera of the vaccinees was observed. Conclusions: The MSP142/Alhydrogel vaccines were safe and well tolerated but not sufficiently immunogenic to generate a biologic effect in vitro. Addition of immunostimulants to the Alhydrogel formulation to elicit higher vaccine-induced responses in humans may be required for an effective vaccine. Background: Generally, adults living in parts of the world where malaria is common develop protective immunity against the parasite. This means they may get infected but not become ill as a result. However, there are individuals, such as pregnant women and children under the age of five, who are more likely to develop symptoms of malaria due to no (or reduced) natural immunity. A successful malaria vaccine would stimulate an individual's immune system to respond to the malaria parasite and prevent serious clinical disease. Many different groups are currently developing potential vaccines. Several candidates are based on a protein called MSP1 (merozoite surface protein 1) which is found on the surface of the blood-stage form of the malaria parasite. However, in nature parasites carry different versions of the MSP1 protein, and ideally a successful vaccine would bring about immune responses against these different versions. The researchers carrying out this trial wanted to compare the safety and immune responses against candidate vaccines representing two different MSP1 proteins, which covered many different parasite lines. As a phase 1 trial, the study was carried out in healthy adult volunteers. Sixty individuals were assigned to receive an injection of the vaccines, either containing a recombinant protein analogous to the FVO parasite line (termed MSP142-FVO) or the 3D7 parasite line (termed MSP142-3D7) at three different dose levels. The trial's primary objective was to assess safety, which was done by collecting data on any abnormal signs or symptoms up to 14 d after each of three vaccinations. These outcomes were graded and then defined as related to the vaccine or not. The researchers also looked at antibody levels in participants' blood against different variants of the MSP1 protein, as well as using in vitro tests to see whether antibodies from vaccinated individuals could prevent malaria parasites from growing in lab culture. What the trial shows: The safety outcomes of the trial showed that the most common type of side effect experienced by the volunteers was pain at the injection site. The vast majority of such events were graded as mild, although there was one single case of a severe event (high levels of pain experienced by one volunteer at the injection site). There was no significant association between the chance of side effects and the vaccine dosage that an individual received. Following vaccination, antibody levels against the protein on which the vaccine was based were detected, although these levels dropped over time. The researchers did not see a strong association between the vaccine dosage that individuals received and the level of antibody response. However, the two vaccines when compared seemed to be equally good at raising an immune response and both caused antibodies to be raised corresponding to different variants of the MSP1 protein. However, the antibodies raised did not seem to be particularly effective at preventing malaria parasites from growing in lab culture. Strengths and limitations: Strengths of this study include a comparison of three different dosage levels of the vaccines under study, as well as a comparison of two vaccines based on the same protein, representing different parasite lines. Limitations to the study include the small number of participants, which makes the trial underpowered to detect all but large differences in side effects between the groups being compared. A placebo arm was not included in the trial, so it is not possible to be sure that the numbers of side effects observed here can be attributed to the vaccines or not. Finally, the procedure for assigning individuals to the two different vaccines involved alternation, rather than true randomization, which could have minimized the risk of bias. Contribution to the evidence: The trial reported here is an essential step in vaccine development. The results provide the first evidence relating to safety for these two vaccines, and do not raise any safety concerns at this stage. Although the vaccines raised an immune response, the antibodies raised did not seem to have much of an effect on malaria parasites in vitro. While these vaccines are safe, alternative MSP1 vaccine formulations anticipated to bring about a greater immune response will likely be studied before proceeding to field studies.
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Affiliation(s)
- Elissa Malkin
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Carole A Long
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Anthony W Stowers
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Lanling Zou
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Sanjay Singh
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Nicholas J MacDonald
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - David L Narum
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Aaron P Miles
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Andrew C Orcutt
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Olga Muratova
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Samuel E Moretz
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Hong Zhou
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Ababacar Diouf
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Michael Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Eveline Tierney
- PATH Malaria Vaccine Initiative, Bethesda, Maryland, United States of America
| | - Philip Leese
- Quintiles Phase 1 Services, Lenexa, Kansas, United States of America
| | - Siddhartha Mahanty
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Louis H Miller
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Allan Saul
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Laura B Martin
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail:
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Wu Y, Przysiecki C, Flanagan E, Bello-Irizarry SN, Ionescu R, Muratova O, Dobrescu G, Lambert L, Keister D, Rippeon Y, Long CA, Shi L, Caulfield M, Shaw A, Saul A, Shiver J, Miller LH. Sustained high-titer antibody responses induced by conjugating a malarial vaccine candidate to outer-membrane protein complex. Proc Natl Acad Sci U S A 2006; 103:18243-8. [PMID: 17110440 PMCID: PMC1636993 DOI: 10.1073/pnas.0608545103] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The development of protein subunit vaccines to combat some of the world's deadliest pathogens such as a malaria parasite, Plasmodium falciparum, is stalled, due in part to the inability to induce and sustain high-titer antibody responses. Here, we show the induction of persistent, high-titer antibody responses to recombinant Pfs25H, a human malarial transmission-blocking protein vaccine candidate, after chemical conjugation to the outer-membrane protein complex (OMPC) of Neisseria meningitidis serogroup B and adsorption to aluminum hydroxyphosphate. In mice, the Pfs25H-OMPC conjugate vaccine was >1,000 times more potent in generating anti-Pfs25H ELISA reactivity than a similar 0.5-microg dose of Pfs25H alone in Montanide ISA720, a water-in-oil adjuvant. The immune enhancement requires covalent conjugation between Pfs25H and the OMPC, given that physically mixed Pfs25H and OMPC on aluminum hydroxyphosphate failed to induce greater activity than the nonconjugated Pfs25H on aluminum hydroxyphosphate. The conjugate vaccine Pfs25H-OMPC also was highly immunogenic in rabbits and rhesus monkeys. In rhesus monkeys, the antibody responses were sustained over 18 months, at which time another vaccination with nonconjugated Pfs25H induced strong anamnestic responses. The vaccine-induced anti-Pfs25-specific antibodies in all animal species blocked the transmission of parasites to mosquitoes. Protein antigen conjugation to OMPC or other protein carrier may have general application to a spectrum of protein subunit vaccines to increase immunogenicity without the need for potentially reactogenic adjuvants.
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Affiliation(s)
- Yimin Wu
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
- To whom correspondence may be addressed at:
Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, 5640 Fishers Lane, Rockville MD 20852. E-mail: or
| | | | | | - Sheila N. Bello-Irizarry
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Roxana Ionescu
- Vaccine Pharmaceutical Research, Merck Research Laboratories, 770 Sumneytown Pike, Box 4, West Point, PA 19486
| | - Olga Muratova
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Gelu Dobrescu
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Lynn Lambert
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - David Keister
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Yvette Rippeon
- Vaccine Pharmaceutical Research, Merck Research Laboratories, 770 Sumneytown Pike, Box 4, West Point, PA 19486
| | - Carole A. Long
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | - Li Shi
- Vaccine Pharmaceutical Research, Merck Research Laboratories, 770 Sumneytown Pike, Box 4, West Point, PA 19486
| | | | | | - Allan Saul
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
| | | | - Louis H. Miller
- *Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852; and
- To whom correspondence may be addressed at:
Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, 5640 Fishers Lane, Rockville MD 20852. E-mail: or
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Singh S, Miura K, Zhou H, Muratova O, Keegan B, Miles A, Martin LB, Saul AJ, Miller LH, Long CA. Immunity to recombinant plasmodium falciparum merozoite surface protein 1 (MSP1): protection in Aotus nancymai monkeys strongly correlates with anti-MSP1 antibody titer and in vitro parasite-inhibitory activity. Infect Immun 2006; 74:4573-80. [PMID: 16861644 PMCID: PMC1539572 DOI: 10.1128/iai.01679-05] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A number of malarial blood-stage candidate vaccines are currently being tested in human clinical trials, but our understanding of the relationship between clinical immunity and data obtained from in vitro assays remains inadequate. An in vitro assay which could reliably predict protective immunity in vivo would facilitate vaccine development. Merozoite surface protein1 (MSP1) is a leading blood-stage malaria vaccine candidate, and anti-MSP1 antibodies from individuals that are clinically immune to malaria inhibit the invasion of Plasmodium merozoites into erythrocytes in vitro. Using expression in Escherichia coli and subsequent refolding, we have produced two allelic forms of MSP1(42) (FVO and 3D7). Aotus nancymai monkeys were immunized with MSP1(42)-FVO, MSP1(42)-3D7, or a combination of FVO and 3D7 allelic forms, (MSP1(42)-C1) and were subsequently challenged with Plasmodium falciparum FVO parasites. Sera obtained prior to challenge were tested by standardized enzyme-linked immunosorbent assay (ELISA) to determine antibody titer, and immunoglobulin G (IgG) fractions were also obtained from the same sera; the IgG fractions were tested in an in vitro growth inhibition (GI) assay to evaluate biological activity of the antibodies. Regardless of the immunogen used, all monkeys that had >200,000 ELISA units against MSP1(42)-FVO antigen before challenge controlled their infections. By contrast, all monkeys whose purified IgGs gave <60% inhibition activity in an in vitro GI assay with P. falciparum FVO required treatment for high parasitemia after challenge. There is a strong correlation between ELISA units (Spearman rank correlation of greater than 0.75) or GI activity (Spearman rank correlation of greater than 0.70) and protective immunity judged by various parameters (e.g., cumulative parasitemia or day of patency). These data indicate that, in this monkey model, the ELISA and GI assay values can significantly predict protective immunity induced by a blood-stage vaccine, and they support the use of these assays as part of evaluation of human clinical trials of MSP1-based vaccines.
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Affiliation(s)
- Sanjay Singh
- Antigen Research Section, Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases/National Institutes of Health, TW1, Rockville, Maryland 20852, USA.
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28
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Malkin EM, Diemert DJ, McArthur JH, Perreault JR, Miles AP, Giersing BK, Mullen GE, Orcutt A, Muratova O, Awkal M, Zhou H, Wang J, Stowers A, Long CA, Mahanty S, Miller LH, Saul A, Durbin AP. Phase 1 clinical trial of apical membrane antigen 1: an asexual blood-stage vaccine for Plasmodium falciparum malaria. Infect Immun 2005; 73:3677-85. [PMID: 15908397 PMCID: PMC1111886 DOI: 10.1128/iai.73.6.3677-3685.2005] [Citation(s) in RCA: 207] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Apical membrane antigen 1 (AMA1), a polymorphic merozoite surface protein, is a leading blood-stage malaria vaccine candidate. A phase 1 trial was conducted with 30 malaria-naive volunteers to assess the safety and immunogenicity of the AMA1-C1 malaria vaccine. AMA1-C1 contains an equal mixture of recombinant proteins based on sequences from the FVO and 3D7 clones of Plasmodium falciparum. The proteins were expressed in Pichia pastoris and adsorbed on Alhydrogel. Ten volunteers in each of three dose groups (5 mug, 20 mug, and 80 mug) were vaccinated in an open-label study at 0, 28, and 180 days. The vaccine was well tolerated, with pain at the injection site being the most commonly observed reaction. Anti-AMA1 immunoglobulin G (IgG) was detected by enzyme-linked immunosorbent assay (ELISA) in 15/28 (54%) volunteers after the second immunization and in 23/25 (92%) after the third immunization, with equal reactivity to both AMA1-FVO and AMA1-3D7 vaccine components. A significant dose-response relationship between antigen dose and antibody response by ELISA was observed, and the antibodies were predominantly of the IgG1 isotype. Confocal microscopic evaluation of sera from vaccinated volunteers demonstrated reactivity with P. falciparum schizonts in a pattern similar to native parasite AMA1. Antigen-specific in vitro inhibition of both FVO and 3D7 parasites was achieved with IgG purified from sera of vaccinees, demonstrating biological activity of the antibodies. To our knowledge, this is the first AMA1 vaccine candidate to elicit functional immune responses in malaria-naive humans, and our results support the further development of this vaccine.
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Affiliation(s)
- Elissa M Malkin
- Johns Hopkins University Bloomberg School of Public Health, Center for Immunization Research, 624 N. Broadway, Room 217, Baltimore, MD 21205, USA.
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29
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Chambers DR, Procter J, Muratova O, Byrne K, Keister D, Shanks D, Magill A, Stroncek D. In vitro RBC exposure to Plasmodium falciparum has no effect on RBC antigen expression. Transfus Med 2002; 12:213-9. [PMID: 12071878 DOI: 10.1046/j.1365-3148.2002.00375.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Severe malarial anaemia is a leading cause of death in African children younger than 3 years of age who are infected with Plasmodium falciparum. The pathogenesis of this anaemia is not understood. The purpose of this study was to determine if P. falciparum induces changes in RBC membranes that contribute to the immune destruction of RBCs. RBCs were collected from healthy subjects and tested using standard haemagglutination assays for 45 antigens representing 21 blood group systems/collections before and after exposure to P. falciparum, strain FVO. Lectins were used to determine whether crypt or neoantigens were expressed on the RBC membrane. Polybrene was used to detect changes in sialic acid. RBCs were cultured in vitro with and without the parasite, and blinded serologic studies were completed. CD35 (complement receptor 1), CD55 (decay-accelerating factor), CD59 (membrane inhibitor of reactive lysis) and CD47 (integrin-associated protein) flow cytometric assays were compared for infected and uninfected RBCs. The percentage of parasitaemia was determined using Giemsa-stained thin blood films. Two (Ch, Lub) of the 45 antigens had differing strengths of agglutination between infected and uninfected RBCs, but these differences were resolved with a second source of antisera. Forty-three antigens showed no significant differences in the strength of agglutination between the infected and uninfected RBCs. Lectin and polybrene testing showed no differences. CD35, CD55, CD59 and CD47 levels showed no significant differences. P. falciparum does not appear to alter the expression of classified immunogenic antigens on the RBC membrane in this in vitro system. The pathogenesis of the haemolytic episode that occurs in these children remains unclear.
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Affiliation(s)
- D R Chambers
- Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institute of Allergy and Infectious Diseases/NIH, Building 10, Room 1C711, 120 Center Drive, Bethesda, MD 20892, USA
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30
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Stowers AW, Cioce V, Shimp RL, Lawson M, Hui G, Muratova O, Kaslow DC, Robinson R, Long CA, Miller LH. Efficacy of two alternate vaccines based on Plasmodium falciparum merozoite surface protein 1 in an Aotus challenge trial. Infect Immun 2001; 69:1536-46. [PMID: 11179324 PMCID: PMC98053 DOI: 10.1128/iai.69.3.1536-1546.2001] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In an attempt to produce a more defined, clinical-grade version of a vaccine based on Plasmodium falciparum merozoite surface protein 1 (MSP1), we evaluated the efficacy of two recombinant forms of MSP1 in an Aotus nancymai challenge model system. One recombinant vaccine, bvMSP1(42), based on the 42-kDa C-terminal portion of MSP1, was expressed as a secreted protein in baculovirus-infected insect cells. A highly pure baculovirus product could be reproducibly expressed and purified at yields in excess of 8 mg of pure protein per liter of culture. This protein, when tested for efficacy in the Aotus challenge model, gave significant protection, with only one of seven monkeys requiring treatment for uncontrolled parasitemia after challenge with P. falciparum. The second recombinant protein, P30P2MSP1(19), has been used in previous studies and is based on the smaller, C-terminal 19-kDa portion of MSP1 expressed in Saccharomyces cerevisiae. Substantial changes were made in its production process to optimize expression. The optimum form of this vaccine antigen (as judged by in vitro and in vivo indicators) was then evaluated, along with bvMSP1(42), for efficacy in the A. nancymai system. The new formulation of P30P3MSP1(19) performed significantly worse than bvMSP1(42) and appeared to be less efficacious than we have found in the past, with four of seven monkeys in the vaccinated group requiring treatment for uncontrolled parasitemia. With both antigens, protection was seen only when high antibody levels were obtained by formulation of the vaccines in Freund's adjuvant. Vaccine formulation in an alternate adjuvant, MF59, resulted in significantly lower antibody titers and no protection.
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Affiliation(s)
- A W Stowers
- Malaria Vaccine Development Unit, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Inc., Rockville, Maryland 20852, USA.
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31
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Gozar MM, Muratova O, Keister DB, Kensil CR, Price VL, Kaslow DC. Plasmodium falciparum: immunogenicity of alum-adsorbed clinical-grade TBV25-28, a yeast-secreted malaria transmission-blocking vaccine candidate. Exp Parasitol 2001; 97:61-9. [PMID: 11281702 DOI: 10.1006/expr.2000.4580] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Gozar, M. M. G., Muratova, O., Keister, D. B., Kensil, C. R., Price, V. L., and Kaslow, D. C. 2001. Plasmodium falciparum: Immunogenicity of alum-adsorbed clinical-grade TBV25-28, a yeast-secreted malaria transmission-blocking vaccine candidate. Experimental Parasitology 97, 61-69. The fusion of Pfs25 and Pfs28, two major surface antigens on zygotes and ookinetes of Plasmodium falciparum, as a single recombinant protein (TBV25-28) was previously shown to elicit potent transmission-blocking antibodies in mice. Clinical-grade TBV25-28 was subsequently manufactured and its potency was evaluated in rabbits. Rabbits received three doses of either clinical-grade TBV25H or clinical-grade TBV25-28 adsorbed to alum with or without QS-21. As measured in a standard membrane-feeding assay, addition of QS-21 to the formulations appeared to enhance transmission-blocking potency of rabbit sera after two vaccinations but not after three vaccinations. Surprisingly, TBV25H elicited more potent transmission-blocking antibodies than did TBV25-28, a result strikingly different from those of previous mouse experiments using research-grade TBV25-28. The apparent decrease in potency of clinical-grade TBV25-28 in rabbits appears to reflect an enhancement in potency of clinical-grade TBV25H in a new formulation rather than simply a species difference in immunogenicity of TBV25-28.
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Affiliation(s)
- M M Gozar
- Malaria Vaccines Section, National Institutes of Health, Bethesda, Maryland 20892, U.S.A
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32
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Stowers AW, Keister DB, Muratova O, Kaslow DC. A region of Plasmodium falciparum antigen Pfs25 that is the target of highly potent transmission-blocking antibodies. Infect Immun 2000; 68:5530-8. [PMID: 10992450 PMCID: PMC101502 DOI: 10.1128/iai.68.10.5530-5538.2000] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Each of the four epidermal growth factor (EGF)-like domains of the Plasmodium falciparum sexual-stage antigen Pfs25 has been individually expressed as a yeast-secreted recombinant protein (yEGF1 through yEGF4). All four are recognized by the immune sera of animals and humans vaccinated with TBV25H (the corresponding yeast-secreted full-length recombinant form of Pfs25), with antibody titers to yEGF1 and yEGF2 weakly correlating with the ability of the sera to block the transmission of parasites to the mosquito host. All four proteins are poorly immunogenic in mice vaccinated with aluminum hydroxide-absorbed formulations. However, all four successfully primed the mice to mount an effective secondary antibody response after a single boost with TBV25H. Sera from mice vaccinated with yEGF2-TBV25H completely block the development of oocysts in mosquito midguts in membrane-feeding assays. Further, of the four proteins, only the depletion of antibodies to yEGF2 from the sera of rabbits vaccinated with TBV25H consistently abolished the ability of those sera to block oocyst development. Thus, antibodies to the second EGF-like domain of Pfs25 appear to mediate a very potent blocking activity, even at low titers. Vaccination strategies that target antibody response towards this domain may improve the efficacy of future transmission-blocking vaccines.
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Affiliation(s)
- A W Stowers
- Malaria Vaccine Development Unit, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-0425, USA.
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Bustamante PJ, Woodruff DC, Oh J, Keister DB, Muratova O, Williamson KC. Differential ability of specific regions of Plasmodium falciparum sexual-stage antigen, Pfs230, to induce malaria transmission-blocking immunity. Parasite Immunol 2000; 22:373-80. [PMID: 10972844 DOI: 10.1046/j.1365-3024.2000.00315.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Antibodies raised against an Escherichia coli-produced recombinant protein encoding a 76-kDa section (region C) of malaria transmission-blocking vaccine candidate, Pfs230, have previously been shown to significantly reduce the ability of Plasmodium falciparum parasites to infect mosquitoes (71.2-89.8%). To further define the region of the Pfs230 required for transmission-blocking activity, four recombinant proteins each encoding a section of region C (Pfs230 amino acids 443-1132) were produced using the same E. coli expression system and tested for immunogenicity in mice: (i) r230/MBP.C5' encodes the first half of region C (amino acids 443-791, six cysteines); (ii) r230/MBP.CM1 encodes only cysteine motif (CM) 1 (amino acids 583-913, eight cysteines); (iii) r230/MBP.C1.6 (amino acids 453-913, eight cysteines) also includes all of CM1; and (iv) r230/MBP.C2 encodes only CM2 (amino acids 914-1268, 11 cysteines). All the recombinant proteins induced antibodies that recognized parasite-produced Pfs230, but the titre of the Pfs230 specific-antibodies generated varied, C = C1.6 = C5' > CM1 > CM2. Two recombinants, r230/MBP.C5' and r230/MBP.C1.6, induced antibody titres that were equivalent to or greater than the titre generated by r230/MBP.C. However, in contrast to r230/MBP.C, none of the recombinants induced antibodies that effectively blocked parasite infectivity to mosquitoes. This suggests that the inclusion of amino acids 914-1132 is important for the production of the transmission-blocking epitope present in region C.
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Affiliation(s)
- P J Bustamante
- Department of Biology, Loyola University of Chicago, IL 60626, USA
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Toure YT, Doumbo O, Toure A, Bagayoko M, Diallo M, Dolo A, Vernick KD, Keister DB, Muratova O, Kaslow DC. Gametocyte infectivity by direct mosquito feeds in an area of seasonal malaria transmission: implications for Bancoumana, Mali as a transmission-blocking vaccine site. Am J Trop Med Hyg 1998; 59:481-6. [PMID: 9749648 DOI: 10.4269/ajtmh.1998.59.481] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Infectivity of gametocytemic volunteers living in Bancoumana, a village 60 km from Bamako, Mali, was determined by direct feeds of laboratory-reared Anopheles gambiae s. l. Gametocytemic adolescents (10-18 years old) were as infectious to mosquitoes as younger volunteers and appear to be a more suitable population for testing transmission-blocking efficacy as compared with adults (> 18 years old). To begin to validate the membrane-feeding assay, sera collected from these same volunteers were subjected to a standard membrane-feeding assay. The data suggest that areas with intense but seasonal transmission might be feasible sites for testing transmission-blocking vaccines because of the high gametocytemic rates, high mosquito infectivity rates, and lack of pre-existing humoral-mediated transmission-blocking activity. The differences observed between field-based direct mosquito feeds and laboratory-based membrane feeding assays suggests that caution be used in interpreting Phase I study results in which laboratory-based membrane-feeding assays are used as a surrogate for vaccine efficacy.
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Affiliation(s)
- Y T Toure
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Bamako, Mali
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Templeton TJ, Keister DB, Muratova O, Procter JL, Kaslow DC. Adherence of erythrocytes during exflagellation of Plasmodium falciparum microgametes is dependent on erythrocyte surface sialic acid and glycophorins. J Exp Med 1998; 187:1599-609. [PMID: 9584138 PMCID: PMC2212290 DOI: 10.1084/jem.187.10.1599] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Malaria male gametocytes within a newly ingested infected blood meal in the mosquito midgut emerge from erythrocytes and extrude approximately eight flagellar microgametes in a process termed exflagellation. In culture, and in blood removed from infected patients, emerging microgametes avidly adhere to neighboring uninfected and infected erythrocytes, as well as to emerged female macrogametes, creating "exflagellation centers". The mechanism of erythrocyte adherence is not known nor has it been determined for what purpose microgametes may bind to erythrocytes. The proposition of a function underlying erythrocyte adherence is supported by the observation of species-specificity in adhesion: microgametes of the human malaria Plasmodium falciparum can bind human erythrocytes but not chicken erythrocytes, whereas avian host Plasmodium gallinaceum microgametes bind chicken but not human erythrocytes. In this study we developed a binding assay in which normal, enzyme-treated, variant or null erythrocytes are identified by a cell surface fluorescent label and assayed for adherence to exflagellating microgametes. Neuraminidase, trypsin or ficin treatment of human erythrocytes eliminated their ability to adhere to Plasmodium falciparum microgametes, suggesting a role of sialic acid and one or more glycophorins in the binding to a putative gamete receptor. Using nulls lacking glycophorin A [En(a-)], glycophorin B (S-s-U-) or a combination of glycophorin A and B (Mk/Mk) we showed that erythrocytes lacking glycophorin B retain the ability to bind but a lack of glycophorin A reduced adherence by exflagellating microgametes. We propose that either the sialic acid moiety of glycophorins, predominantly glycophorin A, or a more complex interaction involving the glycophorin peptide backbone, is the erythrocyte receptor for adhesion to microgametes.
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Affiliation(s)
- T J Templeton
- Malaria Vaccines Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Guinet F, Dvorak JA, Fujioka H, Keister DB, Muratova O, Kaslow DC, Aikawa M, Vaidya AB, Wellems TE. A developmental defect in Plasmodium falciparum male gametogenesis. J Biophys Biochem Cytol 1996; 135:269-78. [PMID: 8858179 PMCID: PMC2121010 DOI: 10.1083/jcb.135.1.269] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Asexually replicating populations of Plasmodium parasites, including those from cloned lines, generate both male and female gametes to complete the malaria life cycle through the mosquito. The generation of these sexual forms begins with the induction of gametocytes from haploid asexual stage parasites in the blood of the vertebrate host. The molecular processes that govern the differentiation and development of the sexual forms are largely unknown. Here we describe a defect that affects the development of competent male gametocytes from a mutant clone of P. falciparum (Dd2). Comparison of the Dd2 clone to the predecessor clone from which it was derived (W2'82) shows that the defect is a mutation that arose during the long-term cultivation of asexual stages in vitro. Light and electron microscopic images, and indirect immunofluorescence assays with male-specific anti-alpha-tubulin II antibodies, indicate a global disruption of male development at the gametocyte level with at least a 70-90% reduction in the proportion of mature male gametocytes by the Dd2 clone relative to W2'82. A high prevalence of abnormal gametocyte forms, frequently containing multiple and unusually large vacuoles, is associated with the defect. The reduced production of mature male gametocytes may reflect a problem in processes that commit a gametocyte to male development or a progressive attrition of viable male gametocytes during maturation. The defect is genetically linked to an almost complete absence of male gamete production and of infectivity to mosquitoes. This is the first sex-specific developmental mutation identified and characterized in Plasmodium.
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Affiliation(s)
- F Guinet
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-0425, USA
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Williamson KC, Keister DB, Muratova O, Kaslow DC. Recombinant Pfs230, a Plasmodium falciparum gametocyte protein, induces antisera that reduce the infectivity of Plasmodium falciparum to mosquitoes. Mol Biochem Parasitol 1995; 75:33-42. [PMID: 8720173 DOI: 10.1016/0166-6851(95)02507-3] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Six regions of malaria transmission-blocking target antigen, Pfs230, encoding 80% of the 363-kDa protein, were expressed as recombinant proteins in E. coli as fusions with maltose-binding protein (MBP). Antisera generated against amylose-purified recombinant Pfs230/MBP fusion proteins (r230/MBP.A-r230/MBP.F) all recognized the 360-kDa form of parasite-produced Pfs230 by immunoblot. However, only antisera against the four carboxy regions (C-F) of Pfs230 and not the two amino regions (A and B) recognized the 310-kDa form of Pfs230, the form expressed on the surface of gametes. The data suggest that the 310-kDa form of Pfs230 arises from the cleavage of 50 kDa from the amino terminus of the 360-kDa form. Furthermore, antisera against r230/MBP.C bound to the surface of intact gametes and significantly reduced (by 71.2-89.8% (rank sum analysis, P < 0.01)) the infectivity of P. falciparum parasites to mosquitoes. This is the first report of a recombinant form of a P. falciparum gametocyte protein capable of inducing antisera that reduce malaria parasite infectivity to mosquitoes.
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Affiliation(s)
- K C Williamson
- Biology Department, Loyola University, Chicago, IL 60626, USA
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Vaidya AB, Muratova O, Guinet F, Keister D, Wellems TE, Kaslow DC. A genetic locus on Plasmodium falciparum chromosome 12 linked to a defect in mosquito-infectivity and male gametogenesis. Mol Biochem Parasitol 1995; 69:65-71. [PMID: 7723789 DOI: 10.1016/0166-6851(94)00199-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Infection of mosquitoes by Plasmodium spp. requires sexual differentiation of the malarial parasite in the vertebrate host and mating of the heterogametes in the vector midgut. A Plasmodium falciparum clone, Dd2, differentiates into normal-appearing gametocytes, yet poorly infects mosquitoes. The Dd2 clone, however, effectively cross-fertilized HB3, a Central American P. falciparum clone, and yielded several independent recombinant progeny. We have examined 11 HB3 x Dd2 progeny for their ability to infect mosquitoes and to differentiate into male gametes. Our analyses indicate that the poor mosquito-infectivity of the Dd2 clone results from a defect in male gametogenesis. This defect was inherited as a single locus in the independent recombinant progeny of HB3 x Dd2. Comparison with a restriction fragment length polymorphism map of the HB3 x Dd2 cross indicates that the defective phenotype of Dd2 maps to a locus on P. falciparum chromosome 12. This genetic locus may contain determinants that play a crucial role in male gametogenesis by P. falciparum.
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Affiliation(s)
- A B Vaidya
- Laboratory of Malaria Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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