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Palatnik-de-Sousa CB, Nico D. The Delay in the Licensing of Protozoal Vaccines: A Comparative History. Front Immunol 2020; 11:204. [PMID: 32210953 PMCID: PMC7068796 DOI: 10.3389/fimmu.2020.00204] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/27/2020] [Indexed: 11/13/2022] Open
Abstract
Although viruses and bacteria have been known as agents of diseases since 1546, 250 years went by until the first vaccines against these pathogens were developed (1796 and 1800s). In contrast, Malaria, which is a protozoan-neglected disease, has been known since the 5th century BCE and, despite 2,500 years having passed since then, no human vaccine has yet been licensed for Malaria. Additionally, no modern human vaccine is currently licensed against Visceral or Cutaneous leishmaniasis. Vaccination against Malaria evolved from the inoculation of irradiated sporozoites through the bite of Anopheles mosquitoes in 1930's, which failed to give protection, to the use of controlled human Malaria infection (CHMI) provoked by live sporozoites of Plasmodium falciparum and curtailed with specific chemotherapy since 1940's. Although the use of CHMI for vaccination was relatively efficacious, it has some ethical limitations and was substituted by the use of injected recombinant vaccines expressing the main antigens of the parasite cycle, starting in 1980. Pre-erythrocytic (PEV), Blood stage (BSV), transmission-blocking (TBV), antitoxic (AT), and pregnancy-associated Malaria vaccines are under development. Currently, the RTS,S-PEV vaccine, based on the circumsporozoite protein, is the only one that has arrived at the Phase III trial stage. The "R" stands for the central repeat region of Plasmodium (P.) falciparum circumsporozoite protein (CSP); the "T" for the T-cell epitopes of the CSP; and the "S" for hepatitis B surface antigen (HBsAg). In Africa, this latter vaccine achieved only 36.7% vaccine efficacy (VE) in 5-7 years old children and was associated with an increase in clinical cases in one assay. Therefore, in spite of 35 years of research, there is no currently licensed vaccine against Malaria. In contrast, more progress has been achieved regarding prevention of leishmaniasis by vaccine, which also started with the use of live vaccines. For ethical reasons, these were substituted by second-generation subunit or recombinant DNA and protein vaccines. Currently, there is one live vaccine for humans licensed in Uzbekistan, and four licensed veterinary vaccines against visceral leishmaniasis: Leishmune® (76-80% VE) and CaniLeish® (68.4% VE), which give protection against strong endpoints (severe disease and deaths under natural conditions), and, under less severe endpoints (parasitologically and PCR-positive cases), Leishtec® developed 71.4% VE in a low infective pressure area but only 35.7% VE and transient protection in a high infective pressure area, while Letifend® promoted 72% VE. A human recombinant vaccine based on the Nucleoside hydrolase NH36 of Leishmania (L.) donovani, the main antigen of the Leishmune® vaccine, and the sterol 24-c-methyltransferase (SMT) from L. (L.) infantum has reached the Phase I clinical trial phase but has not yet been licensed against the disease. This review describes the history of vaccine development and is focused on licensed formulations that have been used in preventive medicine. Special attention has been given to the delay in the development and licensing of human vaccines against Protozoan infections, which show high incidence worldwide and still remain severe threats to Public Health.
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MESH Headings
- Adult
- Animals
- Child
- Child, Preschool
- Female
- History, 17th Century
- History, 18th Century
- History, 19th Century
- History, 20th Century
- History, 21st Century
- Humans
- Leishmania donovani/immunology
- Leishmaniasis Vaccines/history
- Leishmaniasis Vaccines/immunology
- Leishmaniasis, Visceral/parasitology
- Leishmaniasis, Visceral/prevention & control
- Leishmaniasis, Visceral/veterinary
- Licensure/history
- Malaria Vaccines/history
- Malaria Vaccines/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Mass Vaccination/history
- Mass Vaccination/methods
- Plasmodium falciparum/immunology
- Pregnancy
- Vaccines, Attenuated/history
- Vaccines, Attenuated/immunology
- Vaccines, Live, Unattenuated/history
- Vaccines, Live, Unattenuated/immunology
- Vaccines, Synthetic/history
- Vaccines, Synthetic/immunology
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Affiliation(s)
- Clarisa Beatriz Palatnik-de-Sousa
- Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Institute for Research in Immunology, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Dirlei Nico
- Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Shabani SH, Zakeri S, Mortazavi Y, Mehrizi AA. Immunological evaluation of two novel engineered Plasmodium vivax circumsporozoite proteins formulated with different human-compatible vaccine adjuvants in C57BL/6 mice. Med Microbiol Immunol 2019; 208:731-745. [DOI: 10.1007/s00430-019-00606-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 04/01/2019] [Indexed: 12/28/2022]
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3
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Abstract
Safe and efficacious vaccines are arguably the most successful medical interventions of all time. Yet the ongoing discovery of new pathogens, along with emergence of antibiotic-resistant pathogens and a burgeoning population at risk of such infections, imposes unprecedented public health challenges. To meet these challenges, innovative strategies to discover and develop new or improved anti-infective vaccines are necessary. These approaches must intersect the most meaningful insights into protective immunity and advanced technologies with capabilities to deliver immunogens for optimal immune protection. This goal is considered through several recent advances in host-pathogen relationships, conceptual strides in vaccinology, and emerging technologies. Given a clear and growing risk of pandemic disease should the threat of infection go unmet, developing vaccines that optimize protective immunity against high-priority and antibiotic-resistant pathogens represents an urgent and unifying imperative.
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Affiliation(s)
- Michael R Yeaman
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California 90024.,Division of Molecular Medicine, Department of Medicine, Harbor-UCLA Medical Center, Torrance, California 90509; .,Division of Infectious Diseases, Department of Medicine, Harbor-UCLA Medical Center, Torrance, California 90509.,Los Angeles Biomedical Research Institute, Torrance, California 90502
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4
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Biological, immunological and functional properties of two novel multi-variant chimeric recombinant proteins of CSP antigens for vaccine development against Plasmodium vivax infection. Mol Immunol 2017; 90:158-171. [PMID: 28800475 DOI: 10.1016/j.molimm.2017.06.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/31/2017] [Accepted: 06/19/2017] [Indexed: 01/30/2023]
Abstract
The circumsporozoite protein (CSP) of the malaria parasite Plasmodium vivax is a major pre-erythrocyte vaccine candidate. The protein has a central repeat region that belongs to one of repeat families (VK210, VK247, and the P. vivax-like). In the present study, computer modelling was employed to select chimeric proteins, comprising the conserved regions and different arrangements of the repeat elements (VK210 and VK247), whose structure is similar to that of the native counterparts. DNA encoding the selected chimeras (named CS127 and CS712) were synthetically constructed based on E. coli codons, then cloned and expressed. Mouse monoclonal antibodies (mAbs; anti-Pv-210-CDC and -Pv-247-CDC), recognized the chimeric antigens in ELISA, indicating correct conformation and accessibility of the B-cell epitopes. ELISA using IgG from plasma samples collected from 221 Iranian patients with acute P. vivax showed that only 49.32% of the samples reacted to both CS127 and CS712 proteins. The dominant subclass for the two chimeras was IgG1 (48% of the positive responders, OD492=0.777±0.420 for CS127; 48.41% of the positive responders, OD492=0.862±0.423 for CS712, with no statistically significant difference P>0.05; Wilcoxon signed ranks test). Binding assays showed that both chimeric proteins bound to immobilized heparan sulphate and HepG2 hepatocyte cells in a concentration-dependent manner, saturable at 80μg/mL. Additionally, anti-CS127 and -CS712 antibodies raised in mice recognized the native protein on the surface of P. vivax sporozoite with high intensity, confirming the presence of common epitopes between the recombinant forms and the native proteins. In summary, despite structural differences at the molecular level, the expression levels of both chimeras were satisfactory, and their conformational structure retained biological function, thus supporting their potential for use in the development of vivax-based vaccine.
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5
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Salman AM, Montoya-Díaz E, West H, Lall A, Atcheson E, Lopez-Camacho C, Ramesar J, Bauza K, Collins KA, Brod F, Reis F, Pappas L, González-Cerón L, Janse CJ, Hill AVS, Khan SM, Reyes-Sandoval A. Rational development of a protective P. vivax vaccine evaluated with transgenic rodent parasite challenge models. Sci Rep 2017; 7:46482. [PMID: 28417968 PMCID: PMC5394459 DOI: 10.1038/srep46482] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/15/2017] [Indexed: 01/05/2023] Open
Abstract
Development of a protective and broadly-acting vaccine against the most widely distributed human malaria parasite, Plasmodium vivax, will be a major step towards malaria elimination. However, a P. vivax vaccine has remained elusive by the scarcity of pre-clinical models to test protective efficacy and support further clinical trials. In this study, we report the development of a highly protective CSP-based P. vivax vaccine, a virus-like particle (VLP) known as Rv21, able to provide 100% sterile protection against a stringent sporozoite challenge in rodent models to malaria, where IgG2a antibodies were associated with protection in absence of detectable PvCSP-specific T cell responses. Additionally, we generated two novel transgenic rodent P. berghei parasite lines, where the P. berghei csp gene coding sequence has been replaced with either full-length P. vivax VK210 or the allelic VK247 csp that additionally express GFP-Luciferase. Efficacy of Rv21 surpassed viral-vectored vaccination using ChAd63 and MVA. We show for the first time that a chimeric VK210/247 antigen can elicit high level cross-protection against parasites expressing either CSP allele, which provide accessible and affordable models suitable to support the development of P. vivax vaccines candidates. Rv21 is progressing to GMP production and has entered a path towards clinical evaluation.
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Affiliation(s)
- Ahmed M Salman
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK.,Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, (LUMC, L4-Q), Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Eduardo Montoya-Díaz
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Heather West
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Amar Lall
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Erwan Atcheson
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Cesar Lopez-Camacho
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Jai Ramesar
- Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, (LUMC, L4-Q), Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Karolis Bauza
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Katharine A Collins
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Florian Brod
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Fernando Reis
- Universidade Federal de Minas Gerais, Belo Horizonte - MG - Brasil
| | - Leontios Pappas
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Lilia González-Cerón
- Centro Regional de Investigación en Salud Pública, Instituto Nacional de Salud Pública, 4ta Avenida Norte y Calle 19 Poniente, Tapachula, Chiapas, CP 30740, Mexico
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, (LUMC, L4-Q), Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Adrian V S Hill
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Shahid M Khan
- Leiden Malaria Research Group, Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, (LUMC, L4-Q), Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Arturo Reyes-Sandoval
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford, OX3 7BN, UK
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6
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Gunawardena S, Karunaweera ND. Advances in genetics and genomics: use and limitations in achieving malaria elimination goals. Pathog Glob Health 2016; 109:123-41. [PMID: 25943157 DOI: 10.1179/2047773215y.0000000015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Success of the global research agenda towards eradication of malaria will depend on the development of new tools, including drugs, vaccines, insecticides and diagnostics. Genetic and genomic information now available for the malaria parasites, their mosquito vectors and human host, can be harnessed to both develop these tools and monitor their effectiveness. Here we review and provide specific examples of current technological advances and how these genetic and genomic tools have increased our knowledge of host, parasite and vector biology in relation to malaria elimination and in turn enhanced the potential to reach that goal. We then discuss limitations of these tools and future prospects for the successful achievement of global malaria elimination goals.
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7
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Teneza-Mora N, Lumsden J, Villasante E. A malaria vaccine for travelers and military personnel: Requirements and top candidates. Vaccine 2015; 33:7551-8. [DOI: 10.1016/j.vaccine.2015.10.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 09/23/2015] [Accepted: 10/02/2015] [Indexed: 10/22/2022]
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8
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Salinas JL, Kissinger JC, Jones DP, Galinski MR. Metabolomics in the fight against malaria. Mem Inst Oswaldo Cruz 2015; 109:589-97. [PMID: 25185001 PMCID: PMC4156452 DOI: 10.1590/0074-0276140043] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 03/11/2014] [Indexed: 02/06/2023] Open
Abstract
Metabolomics uses high-resolution mass spectrometry to provide a chemical fingerprint of thousands of metabolites present in cells, tissues or body fluids. Such metabolic phenotyping has been successfully used to study various biologic processes and disease states. High-resolution metabolomics can shed new light on the intricacies of host-parasite interactions in each stage of the Plasmodium life cycle and the downstream ramifications on the host's metabolism, pathogenesis and disease. Such data can become integrated with other large datasets generated using top-down systems biology approaches and be utilised by computational biologists to develop and enhance models of malaria pathogenesis relevant for identifying new drug targets or intervention strategies. Here, we focus on the promise of metabolomics to complement systems biology approaches in the quest for novel interventions in the fight against malaria. We introduce the Malaria Host-Pathogen Interaction Center (MaHPIC), a new systems biology research coalition. A primary goal of the MaHPIC is to generate systems biology datasets relating to human and non-human primate (NHP) malaria parasites and their hosts making these openly available from an online relational database. Metabolomic data from NHP infections and clinical malaria infections from around the world will comprise a unique global resource.
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Affiliation(s)
- Jorge L Salinas
- Division of Infectious Diseases, Emory University School of Medicine, Emory University, Atlanta, GA, USA
| | - Jessica C Kissinger
- Department of Genetics, Institute of Bioinformatics, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Dean P Jones
- Division of Pulmonary Medicine, Department of Medicine, Emory University School of Medicine, Emory University, Atlanta, GA, USA
| | - Mary R Galinski
- Division of Infectious Diseases, Emory University School of Medicine, Emory University, Atlanta, GA, USA
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9
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Immunization with the MAEBL M2 Domain Protects against Lethal Plasmodium yoelii Infection. Infect Immun 2015; 83:3781-92. [PMID: 26169268 DOI: 10.1128/iai.00262-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 07/03/2015] [Indexed: 01/18/2023] Open
Abstract
Malaria remains a world-threatening disease largely because of the lack of a long-lasting and fully effective vaccine. MAEBL is a type 1 transmembrane molecule with a chimeric cysteine-rich ectodomain homologous to regions of the Duffy binding-like erythrocyte binding protein and apical membrane antigen 1 (AMA1) antigens. Although MAEBL does not appear to be essential for the survival of blood-stage forms, ectodomains M1 and M2, homologous to AMA1, seem to be involved in parasite attachment to erythrocytes, especially M2. MAEBL is necessary for sporozoite infection of mosquito salivary glands and is expressed in liver stages. Here, the Plasmodium yoelii MAEBL-M2 domain was expressed in a prokaryotic vector. C57BL/6J mice were immunized with doses of P. yoelii recombinant protein rPyM2-MAEBL. High levels of antibodies, with balanced IgG1 and IgG2c subclasses, were achieved. rPyM2-MAEBL antisera were capable of recognizing the native antigen. Anti-MAEBL antibodies recognized different MAEBL fragments expressed in CHO cells, showing stronger IgM and IgG responses to the M2 domain and repeat region, respectively. After a challenge with P. yoelii YM (lethal strain)-infected erythrocytes (IE), up to 90% of the immunized animals survived and a reduction of parasitemia was observed. Moreover, splenocytes harvested from immunized animals proliferated in a dose-dependent manner in the presence of rPyM2-MAEBL. Protection was highly dependent on CD4(+), but not CD8(+), T cells toward Th1. rPyM2-MAEBL antisera were also able to significantly inhibit parasite development, as observed in ex vivo P. yoelii erythrocyte invasion assays. Collectively, these findings support the use of MAEBL as a vaccine candidate and open perspectives to understand the mechanisms involved in protection.
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10
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Verma A, Wong DM, Islam R, Tong F, Ghavami M, Mutunga JM, Slebodnick C, Li J, Viayna E, Lam PCH, Totrov MM, Bloomquist JR, Carlier PR. 3-Oxoisoxazole-2(3H)-carboxamides and isoxazol-3-yl carbamates: Resistance-breaking acetylcholinesterase inhibitors targeting the malaria mosquito, Anopheles gambiae. Bioorg Med Chem 2015; 23:1321-40. [PMID: 25684426 PMCID: PMC4346421 DOI: 10.1016/j.bmc.2015.01.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/07/2015] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
Abstract
To identify potential selective and resistance-breaking mosquitocides against the African malaria vector Anopheles gambiae, we investigated the acetylcholinesterase (AChE) inhibitory and mosquitocidal properties of isoxazol-3-yl dimethylcarbamates (15), and the corresponding 3-oxoisoxazole-2(3H)-dimethylcarboxamide isomers (14). In both series, compounds were found with excellent contact toxicity to wild-type susceptible (G3) strain and multiply resistant (Akron) strain mosquitoes that carry the G119S resistance mutation of AChE. Compounds possessing good to excellent toxicity to Akron strain mosquitoes inhibit the G119S mutant of An. gambiae AChE (AgAChE) with ki values at least 10- to 600-fold higher than that of propoxur, a compound that does not kill Akron mosquitoes at the highest concentration tested. On average, inactivation of WT AgAChE by dimethylcarboxamides 14 was 10-20 fold faster than that of the corresponding isoxazol-3-yl dimethylcarbamates 15. X-ray crystallography of dimethylcarboxamide 14d provided insight into that reactivity, a finding that may explain the inhibitory power of structurally-related inhibitors of hormone-sensitive lipase. Finally, human/An. gambiae AChE inhibition selectivities of these compounds were low, suggesting the need for additional structural modification.
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Affiliation(s)
- Astha Verma
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Dawn M Wong
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Rafique Islam
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA
| | - Fan Tong
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA
| | - Maryam Ghavami
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - James M Mutunga
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA
| | - Carla Slebodnick
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Jianyong Li
- Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Elisabet Viayna
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA
| | - Polo C-H Lam
- Molsoft LLC, 11199 Sorrento Valley Road, San Diego, CA 92121, USA
| | - Maxim M Totrov
- Molsoft LLC, 11199 Sorrento Valley Road, San Diego, CA 92121, USA
| | - Jeffrey R Bloomquist
- Department of Entomology and Nematology, Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610, USA
| | - Paul R Carlier
- Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA.
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Sack BK, Miller JL, Vaughan AM, Kappe SHI. Measurement of Antibody-Mediated Reduction of Plasmodium yoelii Liver Burden by Bioluminescent Imaging. Methods Mol Biol 2015; 1325:69-80. [PMID: 26450380 PMCID: PMC8441651 DOI: 10.1007/978-1-4939-2815-6_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Antibodies against the infectious sporozoite stage of malaria have been shown to be effective in preventing infection of the liver and in mitigating the ensuing blood stage. However, only a handful of antibody targets have been vetted and shown to be successful in mediating in vivo protection. Even more limited are the means with which to measure how effectively antibodies can reduce the number of parasites establishing infection in the liver. Traditionally, only qPCR of infected mouse livers could accurately measure liver parasite burden. However, this procedure requires sacrifice of the animal and precludes monitoring of the ensuing blood stage infection. Herein we describe a method of accurately assessing antibody-mediated reduction of parasite liver burden by combining passive or active immunization of mice and mosquito bite challenge with luciferase-expressing transgenic P. yoelii parasites. This method is rapid, reliable and allows for observation of blood stage disease in the same animal. This model will prove integral in screening the efficacy of novel antibody targets as the search for a more effective malaria vaccine continues.
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Affiliation(s)
- Brandon K Sack
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA.
| | - Jessica L Miller
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
| | - Ashley M Vaughan
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
| | - Stefan H I Kappe
- Center for Infectious Disease Research, 307 Westlake Avenue North, Suite 500, Seattle, WA, 98109, USA
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Pfeil J, Sepp KJ, Heiss K, Meister M, Mueller AK, Borrmann S. Protection against malaria by immunization with non-attenuated sporozoites under single-dose piperaquine-tetraphosphate chemoprophylaxis. Vaccine 2014; 32:6005-11. [PMID: 25203450 DOI: 10.1016/j.vaccine.2014.07.112] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/16/2014] [Accepted: 07/28/2014] [Indexed: 11/30/2022]
Abstract
Experimental whole-parasite immunization through concurrent administration of infectious Plasmodium sporozoites with drugs that prevent pathogenic blood-stage infection represents the current benchmark in malaria vaccine development. Key questions concerning translation remain, including the requirement for single-dose drug regimens that can reliably prevent breakthrough infections. We assessed the feasibility and efficacy of immunization with single-dose piperaquine chemoprophylaxis and concurrent sporozoite administration (PPQ-CPS) in the murine P. berghei ANKA/C57BL/6 infection model. We demonstrate that PPQ-CPS is protective with an efficacy comparable to previous findings using whole-parasite immunization under chloroquine chemoprophylaxis. PPQ-CPS immunization resulted in an expansion of intrahepatic and intrasplenic effector memory CD8(+) T cells. In summary, PPQ-CPS appears to be a safe and efficacious immunization regimen in the rodent malaria model and may thus become an important improvement regarding the translation of whole-parasite immunization toward a human malaria vaccine.
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Affiliation(s)
- Johannes Pfeil
- Department of Infectious Diseases, Parasitology Unit, University Hospital, Heidelberg, Germany; Center for Childhood and Adolescent Medicine, General Pediatrics, University Hospital, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg, Germany.
| | - Katharina Jutta Sepp
- Department of Infectious Diseases, Parasitology Unit, University Hospital, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg, Germany
| | - Kirsten Heiss
- Department of Infectious Diseases, Parasitology Unit, University Hospital, Heidelberg, Germany; MalVa GmbH, Heidelberg, Germany
| | - Michael Meister
- German Cancer Research Center (DKFZ), Department of Molecular Immunology (D050), Heidelberg, Germany
| | - Ann-Kristin Mueller
- Department of Infectious Diseases, Parasitology Unit, University Hospital, Heidelberg, Germany; German Center for Infection Research (DZIF), Heidelberg, Germany
| | - Steffen Borrmann
- German Center for Infection Research (DZIF), Tübingen, Germany; Institute for Tropical Medicine, University of Tübingen, Germany
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13
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Smith RC, Colón-López DD, Bosch J. Immunization against a merozoite sheddase promotes multiple invasion of red blood cells and attenuates Plasmodium infection in mice. Malar J 2014; 13:313. [PMID: 25115675 PMCID: PMC4248431 DOI: 10.1186/1475-2875-13-313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/05/2014] [Indexed: 12/31/2022] Open
Abstract
Background Subtilisin-like protease 2 (SUB2) is a conserved serine protease utilized by Plasmodium parasites as a surface sheddase required for successful merozoite invasion of host red blood cells and has been implicated in ookinete invasion of the mosquito midgut. To determine if SUB2 is a suitable vaccine target to interfere with malaria parasite development, the effects of SUB2-immunization on the Plasmodium life cycle were examined in its vertebrate and invertebrate hosts. Methods Swiss Webster mice were immunized with SUB2 peptides conjugated to Keyhole limpet hemocyanin (KLH) or KLH alone, and then challenged with Plasmodium berghei. To determine the effects of immunization on parasite development, infected mice were evaluated by blood film and Giemsa staining. In addition, collected immune sera were used to perform passive immunization experiments in non-immunized, P. berghei-infected mice to determine the potential role of SUB2 in parasite development in the mosquito. Results Following P. berghei challenge, SUB2-immunized mice develop a lower parasitaemia and show improved survival when compared to control immunized mice. Moreover, SUB2 immunization results in an increase in the number of multiply invaded red blood cells, suggesting that SUB2 antibodies interfere with merozoite invasion. Passive immunization experiments imply that SUB2 may not have a major role in ookinete invasion, but this requires further investigation. Conclusion By interfering with red blood cell invasion, immunization against SUB2 limits malaria parasite development and confers protection from severe malaria. Together, these results provide proof-of-principle evidence for future investigation into the use of SUB2 as a vaccine or drug target to interrupt parasite development in more relevant human malaria models. Electronic supplementary material The online version of this article (doi:10.1186/1475-2875-13-313) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | - Jürgen Bosch
- Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
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Deng X, Kokkonda S, El Mazouni F, White J, Burrows JN, Kaminsky W, Charman SA, Matthews D, Rathod PK, Phillips MA. Fluorine modulates species selectivity in the triazolopyrimidine class of Plasmodium falciparum dihydroorotate dehydrogenase inhibitors. J Med Chem 2014; 57:5381-94. [PMID: 24801997 PMCID: PMC4079327 DOI: 10.1021/jm500481t] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Malaria is one of the most serious global infectious diseases. The pyrimidine biosynthetic enzyme Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) is an important target for antimalarial chemotherapy. We describe a detailed analysis of protein-ligand interactions between DHODH and a triazolopyrimidine-based inhibitor series to explore the effects of fluorine on affinity and species selectivity. We show that increasing fluorination dramatically increases binding to mammalian DHODHs, leading to a loss of species selectivity. Triazolopyrimidines bind Plasmodium and mammalian DHODHs in overlapping but distinct binding sites. Key hydrogen-bond and stacking interactions underlying strong binding to PfDHODH are absent in the mammalian enzymes. Increasing fluorine substitution leads to an increase in the entropic contribution to binding, suggesting that strong binding to mammalian DHODH is a consequence of an enhanced hydrophobic effect upon binding to an apolar pocket. We conclude that hydrophobic interactions between fluorine and hydrocarbons provide significant binding energy to protein-ligand interactions. Our studies define the requirements for species-selective binding to PfDHODH and show that the triazolopyrimidine scaffold can alternatively be tuned to inhibit human DHODH, an important target for autoimmune diseases.
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Affiliation(s)
- Xiaoyi Deng
- Department of Pharmacology, University of Texas Southwestern Medical Center at Dallas , 6001 Forest Park Boulevard, Dallas, Texas 75390-9041, United States
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Vitamin B6-dependent enzymes in the human malaria parasite Plasmodium falciparum: a druggable target? BIOMED RESEARCH INTERNATIONAL 2014; 2014:108516. [PMID: 24524072 PMCID: PMC3912857 DOI: 10.1155/2014/108516] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 10/24/2013] [Accepted: 11/28/2013] [Indexed: 11/17/2022]
Abstract
Malaria is a deadly infectious disease which affects millions of people each year in tropical regions. There is no effective vaccine available and the treatment is based on drugs which are currently facing an emergence of drug resistance and in this sense the search for new drug targets is indispensable. It is well established that vitamin biosynthetic pathways, such as the vitamin B6 de novo synthesis present in Plasmodium, are excellent drug targets. The active form of vitamin B6, pyridoxal 5-phosphate, is, besides its antioxidative properties, a cofactor for a variety of essential enzymes present in the malaria parasite which includes the ornithine decarboxylase (ODC, synthesis of polyamines), the aspartate aminotransferase (AspAT, involved in the protein biosynthesis), and the serine hydroxymethyltransferase (SHMT, a key enzyme within the folate metabolism).
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Reisen WK. Medical entomology--back to the future? INFECTION GENETICS AND EVOLUTION 2013; 28:573-82. [PMID: 24316291 DOI: 10.1016/j.meegid.2013.11.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/25/2013] [Accepted: 11/27/2013] [Indexed: 12/29/2022]
Abstract
Some of problems and challenges facing Medical/Veterinary Entomology are presented from my perspective, focusing on the current millennium. Topics include anthropogenic environmental changes created by population growth, administrative problems hindering science's response to these changes, and some of the scientific discoveries potentially providing solutions. As the title implies, many recent research discoveries have yet to be translated into major changes in control approaches for the major vectorborne public health problems, thereby providing an interesting mix of modern surveillance technology used to track problems and direct historical intervention solutions.
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Affiliation(s)
- William K Reisen
- Center for Vectorborne Diseases, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, United States.
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