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MacMillen Z, Hatzakis K, Simpson A, Shears MJ, Watson F, Erasmus JH, Khandhar AP, Wilder B, Murphy SC, Reed SG, Davie JW, Avril M. Accelerated prime-and-trap vaccine regimen in mice using repRNA-based CSP malaria vaccine. NPJ Vaccines 2024; 9:12. [PMID: 38200025 PMCID: PMC10781674 DOI: 10.1038/s41541-023-00799-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 12/12/2023] [Indexed: 01/12/2024] Open
Abstract
Malaria, caused by Plasmodium parasites, remains one of the most devastating infectious diseases worldwide, despite control efforts to lower morbidity and mortality. Both advanced candidate vaccines, RTS,S and R21, are subunit (SU) vaccines that target a single Plasmodium falciparum (Pf) pre-erythrocytic (PE) sporozoite (spz) surface protein known as circumsporozoite (CS). These vaccines induce humoral immunity but fail to elicit CD8 + T-cell responses sufficient for long-term protection. In contrast, whole-organism (WO) vaccines, such as Radiation Attenuated Sporozoites (RAS), achieved sterile protection but require a series of intravenous doses administered in multiple clinic visits. Moreover, these WO vaccines must be produced in mosquitos, a burdensome process that severely limits their availability. To reduce reliance on WO while maintaining protection via both antibodies and Trm responses, we have developed an accelerated vaccination regimen that combines two distinct agents in a prime-and-trap strategy. The priming dose is a single dose of self-replicating RNA encoding the full-length P. yoelii CS protein, delivered via an advanced cationic nanocarrier (LIONTM). The trapping dose consists of one dose of WO RAS. Our vaccine induces a strong immune response when administered in an accelerated regimen, i.e., either 5-day or same-day immunization. Additionally, mice after same-day immunization showed a 2-day delay of blood patency with 90% sterile protection against a 3-week spz challenge. The same-day regimen also induced durable 70% sterile protection against a 2-month spz challenge. Our approach presents a clear path to late-stage preclinical and clinical testing of dose-sparing, same-day regimens that can confer sterilizing protection against malaria.
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Affiliation(s)
- Zachary MacMillen
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle, WA, 98102, USA
| | - Kiara Hatzakis
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle, WA, 98102, USA
| | - Adrian Simpson
- HDT Bio, 1150 Eastlake Ave E, Suite 200A, Seattle, WA, 98109, USA
| | - Melanie J Shears
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA, 98109, USA
| | - Felicia Watson
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA, 98109, USA
| | - Jesse H Erasmus
- HDT Bio, 1150 Eastlake Ave E, Suite 200A, Seattle, WA, 98109, USA
| | - Amit P Khandhar
- HDT Bio, 1150 Eastlake Ave E, Suite 200A, Seattle, WA, 98109, USA
| | - Brandon Wilder
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Building 1, Room 2220, 505 NW 185th Ave, Beaverton, OR, 97006, USA
| | - Sean C Murphy
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA, 98109, USA
| | - Steven G Reed
- HDT Bio, 1150 Eastlake Ave E, Suite 200A, Seattle, WA, 98109, USA
| | - James W Davie
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle, WA, 98102, USA
| | - Marion Avril
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle, WA, 98102, USA.
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Ramzan MS, Suleman M, Rashid MI, Akbar H, Avais M. Comparative evaluation of cell-mediated immune response in calves immunized with live-attenuated and killed Theileria annulata vaccines. Parasitol Res 2023; 122:2135-2145. [PMID: 37466666 DOI: 10.1007/s00436-023-07912-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 06/20/2023] [Indexed: 07/20/2023]
Abstract
Tropical theileriosis is a tick-borne disease caused by the protozoan Theileria annulata and transmitted by numerous species of Ixodid ticks of the genus Hyalomma. The main clinical signs are fever, lymphadenopathy, and anemia responsible for heavy economic losses, including mortality, morbidity, vaccination failure, and treatment cost. Development of poor cell-mediated immunity (CMI) has been observed in the case of many bovine pathogens (bacteria, viruses, and parasites). Quantification of CMI is a prerequisite for evaluating vaccine efficacy against theileriosis caused by T. annulata. The current study evaluated the CMI in calves administered with two types of T. annulata vaccine (live attenuated and killed). We prepared a live attenuated T. annulata vaccine by attenuation in a rabbit model and also prepared killed vaccine from non-attenuated T. annulata. For the evaluation of immune response in experimental groups including control, 20 calves were divided into four different groups (A, B, C, and D). They were either inoculated subcutaneously with live rabbit-propagated-Theileria-infected RBCs (5 × 106) (group A) or with killed T. annulata vaccine (2 × 109 schizonts) with Freund's adjuvant (group B), along with an infected group (group C) and a healthy control group (group D). The protection of vaccinated calves was estimated with challenge infection. Our results showed that with a single shot of live-attenuated and killed vaccine with a booster dose elicited cell-mediated immune responses in immunized calves. We observed a significant elevation in CD4 + and CD8 + T cells in immunized calves. A significant difference in the CD8 + T cell response between the post-challenge stage of killed and live vaccine (p < 0.0001) was observed, whereas no other difference was found at both pre- and post-immunization stages. A similar finding was recorded for the CD4 + T cells at a post-challenge stage, where a significant difference was seen between killed and live vaccine (p < 0.0001). Another significant difference was observed between the CD8 + T cells and CD4 + T cells at the post-challenge stage in the live vaccine group, where there was a significantly higher induction of CD4 + T cell response (p < 0.0001).
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Affiliation(s)
- Muhammad Sajid Ramzan
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, 54200, Pakistan
| | - Muhammad Suleman
- Institute of Microbiology, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan.
| | - Muhammad Imran Rashid
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, 54200, Pakistan.
| | - Haroon Akbar
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, 54200, Pakistan
| | - Muhammad Avais
- Department of Veterinary Medicine, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
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Shears MJ, Watson FN, Stone BC, Cruz Talavera I, Parthiban C, Matsubara J, Kc N, Sim BKL, Hoffman SL, Murphy SC. Preliminary studies on the immunogenicity of a prime-and-trap malaria vaccine in nonhuman primates. Vaccine 2023; 41:5494-5498. [PMID: 37563050 PMCID: PMC10528330 DOI: 10.1016/j.vaccine.2023.07.067] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 07/21/2023] [Accepted: 07/28/2023] [Indexed: 08/12/2023]
Abstract
Development of next-generation vaccines against Plasmodium falciparum (Pf) is a priority. Many malaria vaccines target the pre-erythrocytic sporozoite (SPZ) and liver stages. These include subunit vaccines based on the Pf circumsporozoite protein (CSP) and attenuated PfSPZ vaccines. However, these strategies require 3-4 doses and have not achieved optimal efficacy against field-transmitted malaria. Prime-and-trap is a recently developed two-step heterologous vaccine strategy that combines priming with DNA encoding CSP followed by a single dose of attenuated SPZ. This strategy aims to induce CD8+ T cells that can eliminate parasites in the liver. Prior data has demonstrated that prime-and-trap with P. yoelii CSP and PySPZ was immunogenic and protective in mice. Here we report preliminary data on the immunogenicity of PfCSP prime and PfSPZ trap vaccine in rhesus macaques. This vaccine induced PfCSP-specific antibodies and T cell responses in all animals. However, response magnitude differed between individuals, suggesting further study is required.
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Affiliation(s)
- Melanie J Shears
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States.
| | - Felicia N Watson
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Brad C Stone
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Irene Cruz Talavera
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Chaitra Parthiban
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Jokichi Matsubara
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Natasha Kc
- Sanaria Inc., Rockville, MD, United States
| | | | | | - Sean C Murphy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States; Department of Microbiology, University of Washington, Seattle, WA, United States; Washington National Primate Research Center, University of Washington, Seattle, WA, United States.
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4
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MacMillen Z, Hatzakis K, Simpson A, Shears M, Watson F, Erasmus J, Khandhar A, Wilder B, Murphy S, Reed S, Davie J, Avril M. Accelerated prime-and-trap vaccine regimen in mice using repRNA-based CSP malaria vaccine. RESEARCH SQUARE 2023:rs.3.rs-3045076. [PMID: 37461621 PMCID: PMC10350175 DOI: 10.21203/rs.3.rs-3045076/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Malaria, caused by Plasmodium parasites, remains one of the most devastating infectious diseases worldwide, despite control efforts that have lowered morbidity and mortality. The only P. falciparum vaccine candidates to show field efficacy are those targeting the asymptomatic pre-erythrocytic (PE) stages of infection. The subunit (SU) RTS,S/AS01 vaccine, the only licensed malaria vaccine to date, is only modestly effective against clinical malaria. Both RTS,S/AS01 and the SU R21 vaccine candidate target the PE sporozoite (spz) circumsporozoite (CS) protein. These candidates elicit high-titer antibodies that provide short-term protection from disease, but do not induce the liver-resident memory CD8+ T cells (Trm) that confer strong PE immunity and long-term protection. In contrast, whole-organism (WO) vaccines, employing for example radiation-attenuated spz (RAS), elicit both high antibody titers and Trm, and have achieved high levels of sterilizing protection. However, they require multiple intravenous (IV) doses, which must be administered at intervals of several weeks, complicating mass administration in the field. Moreover, the quantities of spz required present production difficulties. To reduce reliance on WO while maintaining protection via both antibodies and Trm responses, we have developed an accelerated vaccination regimen that combines two distinct agents in a prime-and-trap strategy. While the priming dose is a self-replicating RNA encoding P. yoelii CS protein, delivered via an advanced cationic nanocarrier (LION™), the trapping dose consists of WO RAS. This accelerated regime confers sterile protection in the P. yoelii mouse model of malaria. Our approach presents a clear path to late-stage preclinical and clinical testing of dose-sparing, same-day regimens that can confer sterilizing protection against malaria.
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5
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MacMillen Z, Hatzakis K, Simpson A, Shears MJ, Watson F, Erasmus JH, Khandhar AP, Wilder B, Murphy SC, Reed SG, Davie JW, Avril M. Accelerated prime-and-trap vaccine regimen in mice using repRNA-based CSP malaria vaccine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.23.541932. [PMID: 37292739 PMCID: PMC10245832 DOI: 10.1101/2023.05.23.541932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Malaria, caused by Plasmodium parasites, remains one of the most devastating infectious diseases worldwide, despite control efforts that have lowered morbidity and mortality. The only P. falciparum vaccine candidates to show field efficacy are those targeting the asymptomatic pre-erythrocytic (PE) stages of infection. The subunit (SU) RTS,S/AS01 vaccine, the only licensed malaria vaccine to date, is only modestly effective against clinical malaria. Both RTS,S/AS01 and the SU R21 vaccine candidate target the PE sporozoite (spz) circumsporozoite (CS) protein. These candidates elicit high-titer antibodies that provide short-term protection from disease, but do not induce the liver-resident memory CD8+ T cells (Trm) that confer strong PE immunity and long-term protection. In contrast, whole-organism (WO) vaccines, employing for example radiation-attenuated spz (RAS), elicit both high antibody titers and Trm, and have achieved high levels of sterilizing protection. However, they require multiple intravenous (IV) doses, which must be administered at intervals of several weeks, complicating mass administration in the field. Moreover, the quantities of spz required present production difficulties. To reduce reliance on WO while maintaining protection via both antibodies and Trm responses, we have developed an accelerated vaccination regimen that combines two distinct agents in a prime-and-trap strategy. While the priming dose is a self-replicating RNA encoding P. yoelii CS protein, delivered via an advanced cationic nanocarrier (LION™), the trapping dose consists of WO RAS. This accelerated regime confers sterile protection in the P. yoelii mouse model of malaria. Our approach presents a clear path to late-stage preclinical and clinical testing of dose-sparing, same-day regimens that can confer sterilizing protection against malaria.
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Affiliation(s)
| | - Kiara Hatzakis
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle WA 98102
| | - Adrian Simpson
- HDT Bio, 1616 Eastlake Ave E, Suite 280, Seattle WA 98102
| | - Melanie J. Shears
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA 98109
| | - Felicia Watson
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA 98109
| | | | | | - Brandon Wilder
- Vaccine & Gene Therapy Institute, Oregon Health & Science University, Building 1, Room 2220, 505 NW 185th Ave, Beaverton, OR 97006
| | - Sean C. Murphy
- University of Washington, Department of Laboratory Medicine and Pathology, 750 Republican St., F870, Seattle, WA 98109
| | - Steven G. Reed
- HDT Bio, 1616 Eastlake Ave E, Suite 280, Seattle WA 98102
| | - James W. Davie
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle WA 98102
| | - Marion Avril
- MalarVx, Inc 1551 Eastlake Ave E, Suite 100, Seattle WA 98102
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6
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Morrison WI, Aguado A, Sheldrake TA, Palmateer NC, Ifeonu OO, Tretina K, Parsons K, Fenoy E, Connelley T, Nielsen M, Silva JC. CD4 T Cell Responses to Theileria parva in Immune Cattle Recognize a Diverse Set of Parasite Antigens Presented on the Surface of Infected Lymphoblasts. THE JOURNAL OF IMMUNOLOGY 2021; 207:1965-1977. [PMID: 34507950 DOI: 10.4049/jimmunol.2100331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/22/2021] [Indexed: 12/23/2022]
Abstract
Parasite-specific CD8 T cell responses play a key role in mediating immunity against Theileria parva in cattle (Bos taurus), and there is evidence that efficient induction of these responses requires CD4 T cell responses. However, information on the antigenic specificity of the CD4 T cell response is lacking. The current study used a high-throughput system for Ag identification using CD4 T cells from immune animals to screen a library of ∼40,000 synthetic peptides representing 499 T. parva gene products. Use of CD4 T cells from 12 immune cattle, representing 12 MHC class II types, identified 26 Ags. Unlike CD8 T cell responses, which are focused on a few dominant Ags, multiple Ags were recognized by CD4 T cell responses of individual animals. The Ags had diverse properties, but included proteins encoded by two multimember gene families: five haloacid dehalogenases and five subtelomere-encoded variable secreted proteins. Most Ags had predicted signal peptides and/or were encoded by abundantly transcribed genes, but neither parameter on their own was reliable for predicting antigenicity. Mapping of the epitopes confirmed presentation by DR or DQ class II alleles and comparison of available T. parva genome sequences demonstrated that they included both conserved and polymorphic epitopes. Immunization of animals with vaccine vectors expressing two of the Ags demonstrated induction of CD4 T cell responses capable of recognizing parasitized cells. The results of this study provide detailed insight into the CD4 T cell responses induced by T. parva and identify Ags suitable for use in vaccine development.
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Affiliation(s)
- W Ivan Morrison
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom;
| | - Adriana Aguado
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Tara A Sheldrake
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Nicholas C Palmateer
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD
| | - Olukemi O Ifeonu
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD
| | - Kyle Tretina
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD
| | - Keith Parsons
- Institute for Animal Health, Berkshire, United Kingdom
| | - Emilio Fenoy
- Biotechnological Research Institute, National University of San Martin, Buenos Aires, Argentina
| | - Timothy Connelley
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, United Kingdom
| | - Morten Nielsen
- Biotechnological Research Institute, National University of San Martin, Buenos Aires, Argentina.,Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark; and
| | - Joana C Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD
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7
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Swadling L, Pallett LJ, Diniz MO, Baker JM, Amin OE, Stegmann KA, Burton AR, Schmidt NM, Jeffery-Smith A, Zakeri N, Suveizdyte K, Froghi F, Fusai G, Rosenberg WM, Davidson BR, Schurich A, Simon AK, Maini MK. Human Liver Memory CD8 + T Cells Use Autophagy for Tissue Residence. Cell Rep 2021; 30:687-698.e6. [PMID: 31968246 PMCID: PMC6988113 DOI: 10.1016/j.celrep.2019.12.050] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/04/2019] [Accepted: 12/13/2019] [Indexed: 12/11/2022] Open
Abstract
Tissue-resident memory T cells have critical roles in long-term pathogen and tumor immune surveillance in the liver. We investigate the role of autophagy in equipping human memory T cells to acquire tissue residence and maintain functionality in the immunosuppressive liver environment. By performing ex vivo staining of freshly isolated cells from human liver tissue, we find that an increased rate of basal autophagy is a hallmark of intrahepatic lymphocytes, particularly liver-resident CD8+ T cells. CD8+ T cells with increased autophagy are those best able to proliferate and mediate cytotoxicity and cytokine production. Conversely, blocking autophagy induction results in the accumulation of depolarized mitochondria, a feature of exhausted T cells. Primary hepatic stellate cells or the prototypic hepatic cytokine interleukin (IL)-15 induce autophagy in parallel with tissue-homing/retention markers. Inhibition of T cell autophagy abrogates tissue-residence programming. Thus, upregulation of autophagy adapts CD8+ T cells to combat mitochondrial depolarization, optimize functionality, and acquire tissue residence. An increased rate of basal autophagy is a hallmark of liver-resident CD8+ T cells Enhanced T cell autophagy can be imprinted by IL-15 or hepatic stellate cells Autophagy induction is required for tissue-residence programming in vitro Enhanced autophagy maintains TRM mitochondrial fitness in the liver
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Affiliation(s)
- Leo Swadling
- Division of Infection and Immunity, University College London, London, UK.
| | - Laura J Pallett
- Division of Infection and Immunity, University College London, London, UK
| | - Mariana O Diniz
- Division of Infection and Immunity, University College London, London, UK
| | - Josephine M Baker
- Division of Infection and Immunity, University College London, London, UK
| | - Oliver E Amin
- Division of Infection and Immunity, University College London, London, UK
| | - Kerstin A Stegmann
- Division of Infection and Immunity, University College London, London, UK
| | - Alice R Burton
- Division of Infection and Immunity, University College London, London, UK
| | - Nathalie M Schmidt
- Division of Infection and Immunity, University College London, London, UK
| | - Anna Jeffery-Smith
- Division of Infection and Immunity, University College London, London, UK; Centre for Immunobiology, Blizard Institute, Barts and the London School of Medicine and Dentistry, QMUL, London, UK
| | - Nekisa Zakeri
- Division of Infection and Immunity, University College London, London, UK
| | | | - Farid Froghi
- Institute for Liver and Digestive Health, University College London, London, UK
| | - Giuseppe Fusai
- Institute for Liver and Digestive Health, University College London, London, UK
| | - William M Rosenberg
- Institute for Liver and Digestive Health, University College London, London, UK
| | - Brian R Davidson
- Institute for Liver and Digestive Health, University College London, London, UK
| | - Anna Schurich
- Division of Infection and Immunity, University College London, London, UK; Department of Infectious Diseases, Kings College London, London, UK
| | - A Katharina Simon
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, UK
| | - Mala K Maini
- Division of Infection and Immunity, University College London, London, UK.
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Immunogenic Evaluation of Ribosomal P-Protein Antigen P0, P1, and P2 and Pentameric Protein Complex P0-(P1-P2) 2 of Plasmodium falciparum in a Mouse Model. J Immunol Res 2019; 2019:9264217. [PMID: 31612155 PMCID: PMC6757288 DOI: 10.1155/2019/9264217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Accepted: 08/14/2019] [Indexed: 12/26/2022] Open
Abstract
Malaria remains one the most infectious and destructive protozoan diseases worldwide. Plasmodium falciparum, a protozoan parasite with a complex life cycle and high genetic variability responsible for the difficulties in vaccine development, is implicated in most malaria-related deaths. In the course of study, we prepared a set of antigens based on P-proteins from P. falciparum and determined their immunogenicity in an in vivo assay on a mouse model. The pentameric complex P0-(P1-P2)2 was prepared along with individual P1, P2, and P0 antigens. We determined the level of cellular- and humoral-type immunological response followed by development of specific immunological memory. We have shown that the number of Tc cells increased significantly after the first immunization with P2 and after the second immunization with P1 and P0-(P1-P2)2, which highly correlated with the number of Th1 cells. P0 appeared as a poor inducer of cellular response. After the third boost with P1, P2, or P0-(P1-P2)2, the initially high cellular response dropped to the control level accompanied by elevation of the number of activated Treg cells and a high level of suppressive TGF-β. Subsequently, the humoral response against the examined antigens was activated. Although the titers of specific IgG were increasing during the course of immunization for all antigens used, P2 and P0-(P1-P2)2 were found to be significantly stronger than P1 and P0. A positive correlation between the Th2 cell abundance and the level of IL-10 was observed exclusively after immunization with P0-(P1-P2)2. An in vitro exposure of spleen lymphocytes from the immunized mice especially to the P1, P2, and P0-(P1-P2)2 protein caused 2-3-fold higher cell proliferation than that in the case of lymphocytes from the nonimmunized animals, suggesting development of immune memory. Our results demonstrate for the first time that the native-like P-protein pentameric complex represents much stronger immune potential than individual P-antigens.
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9
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Abstract
Vaccines that target the preerythrocytic phase of malaria hold great promise as elimination tools since they are the sole vaccines that can achieve sterile protection against a challenge. This chapter focuses on preerythrocytic stage vaccines based on live attenuated parasites. It first summarizes the main conclusions that have emerged from studies in rodents, which compared various parasite attenuation methods, and then presents the vaccination regimens that are currently being tested in humans.
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10
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A Plasmodium Parasite with Complete Late Liver Stage Arrest Protects against Preerythrocytic and Erythrocytic Stage Infection in Mice. Infect Immun 2018; 86:IAI.00088-18. [PMID: 29440367 DOI: 10.1128/iai.00088-18] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 02/05/2018] [Indexed: 01/28/2023] Open
Abstract
Genetically attenuated malaria parasites (GAP) that arrest during liver stage development are powerful immunogens and afford complete and durable protection against sporozoite infection. Late liver stage-arresting GAP provide superior protection against sporozoite challenge in mice compared to early live stage-arresting attenuated parasites. However, very few late liver stage-arresting GAP have been generated to date. Therefore, identification of additional loci that are critical for late liver stage development and can be used to generate novel late liver stage-arresting GAPs is of importance. We further explored genetic attenuation in Plasmodium yoelii by combining two gene deletions, PlasMei2 and liver-specific protein 2 (LISP2), that each cause late liver stage arrest with various degrees of infrequent breakthrough to blood stage infection. The dual gene deletion resulted in a synthetic lethal phenotype that caused complete attenuation in a highly susceptible mouse strain. P. yoeliiplasmei2-lisp2- arrested late in liver stage development and did not persist in livers beyond 3 days after infection. Immunization with this GAP elicited robust protective antibody responses in outbred and inbred mice against sporozoites, liver stages, and blood stages as well as eliciting protective liver-resident T cells. The immunization afforded protection against both sporozoite challenge and blood stage challenge. These findings provide evidence that completely attenuated late liver stage-arresting GAP are achievable via the synthetic lethal approach and might enable a path forward for the creation of a completely attenuated late liver stage-arresting P. falciparum GAP.
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11
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Nlinwe ON, Kusi KA, Adu B, Sedegah M. T-cell responses against Malaria: Effect of parasite antigen diversity and relevance for vaccine development. Vaccine 2018; 36:2237-2242. [PMID: 29573877 DOI: 10.1016/j.vaccine.2018.03.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 01/21/2018] [Accepted: 03/07/2018] [Indexed: 11/24/2022]
Abstract
The on-going agenda for global malaria elimination will require the development of additional disease control and prevention measures since currently available tools are showing signs of inadequacy. Malaria vaccines are seen as one such important addition to the control arsenal since vaccines have proven to be highly effective public health tools against important human diseases. Both cell-mediated and antibody responses are generally believed to be important for malaria parasite control, although the exact targets of T and B cell responses against malaria have not been clearly defined. However, our current understanding of the immune response to malaria suggests that T cell responses against multiple antigenic targets may potentially be key for the development of a highly efficacious malaria vaccine. This review takes a comprehensive look at the available literature on T cell-mediated immunity against all human stages of the malaria parasite and the effect of antigen diversity on these responses. The implications of these interrelationships for the development of an effective vaccine for malaria are also highlighted.
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Affiliation(s)
- Omarine Nfor Nlinwe
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, P.O. Box LG 581, Legon, Accra, Ghana.
| | - Kwadwo Asamoah Kusi
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, P.O. Box LG 581, Legon, Accra, Ghana.
| | - Bright Adu
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, P.O. Box LG 581, Legon, Accra, Ghana.
| | - Martha Sedegah
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 209 l0-7500, USA.
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12
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Sarkar S, Hewison M, Studzinski GP, Li YC, Kalia V. Role of vitamin D in cytotoxic T lymphocyte immunity to pathogens and cancer. Crit Rev Clin Lab Sci 2015; 53:132-45. [PMID: 26479950 DOI: 10.3109/10408363.2015.1094443] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The discovery of vitamin D receptor (VDR) expression in immune cells has opened up a new area of research into immunoregulation by vitamin D, a niche that is distinct from its classical role in skeletal health. Today, about three decades since this discovery, numerous cellular and molecular targets of vitamin D in the immune system have been delineated. Moreover, strong clinical associations between vitamin D status and the incidence/severity of many immune-regulated disorders (e.g. infectious diseases, cancers and autoimmunity) have prompted the idea of using vitamin D supplementation to manipulate disease outcome. While much is known about the effects of vitamin D on innate immune responses and helper T (T(H)) cell immunity, there has been relatively limited progress on the frontier of cytotoxic T lymphocyte (CTL) immunity--an arm of host cellular adaptive immunity that is crucial for the control of such intracellular pathogens as human immunodeficiency virus (HIV), tuberculosis (TB), malaria, and hepatitis C virus (HCV). In this review, we discuss the strong historical and clinical link between vitamin D and infectious diseases that involves cytotoxic T lymphocyte (CTL) immunity, present our current understanding as well as critical knowledge gaps in the realm of vitamin D regulation of host CTL responses, and highlight potential regulatory connections between vitamin D and effector and memory CD8 T cell differentiation events during infections.
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Affiliation(s)
- Surojit Sarkar
- a Department of Pediatrics, Division of Hematology and Oncology , University of Washington School of Medicine , Seattle , WA , USA .,b Seattle Children's Research Institute, Ben Towne Center for Childhood Cancer Research , Seattle , WA , USA
| | - Martin Hewison
- c Centre for Endocrinology, Diabetes and Metabolism (CEDAM), The University of Birmingham , Birmingham , UK
| | - George P Studzinski
- d Department of Pathology and Laboratory Medicine , Rutgers New Jersey Medical School , Newark , NJ , USA , and
| | - Yan Chun Li
- e Department of Medicine, Division of Biological Sciences , The University of Chicago , Chicago , IL , USA
| | - Vandana Kalia
- a Department of Pediatrics, Division of Hematology and Oncology , University of Washington School of Medicine , Seattle , WA , USA .,b Seattle Children's Research Institute, Ben Towne Center for Childhood Cancer Research , Seattle , WA , USA
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13
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Humanized Mouse Models to Study Cell-Mediated Immune Responses to Liver-Stage Malaria Vaccines. Trends Parasitol 2015; 31:583-594. [PMID: 26458783 DOI: 10.1016/j.pt.2015.06.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 06/24/2015] [Accepted: 06/25/2015] [Indexed: 12/23/2022]
Abstract
Malaria vaccine development is hampered by the lack of small animal models that recapitulate human immune responses to Plasmodium falciparum. We review the burgeoning literature on humanized mice for P. falciparum infection, including challenges in engraftment of human immune cells, hepatocytes, and erythrocytes. Recent advances in immune-compromised mouse models and stem cell technology have already enabled proof of concept that the entire parasite life cycle can be sustained in a murine model and that adaptive human immune responses to several parasite stages can be measured. Nonetheless, optimization is needed to achieve a reproducible and relevant murine model for malaria vaccine development. This review is focused on the complexities of T cell development in a mouse humanized with both a lymphoid system and hepatocytes. An understanding of this will facilitate the use of humanized mice in the development of liver-stage vaccines.
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14
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Sedegah M, Hollingdale MR, Farooq F, Ganeshan H, Belmonte M, Huang J, Abot E, Limbach K, Chuang I, Tamminga C, Epstein JE, Villasante E. Controlled Human Malaria Infection (CHMI) differentially affects cell-mediated and antibody responses to CSP and AMA1 induced by adenovirus vaccines with and without DNA-priming. Hum Vaccin Immunother 2015; 11:2705-15. [PMID: 26292027 PMCID: PMC4685686 DOI: 10.1080/21645515.2015.1019186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
We have previously shown that a DNA-prime followed by an adenovirus-5 boost vaccine containing CSP and AMA1 (DNA/Ad) successfully protected 4 of 15 subjects to controlled human malaria infection (CHMI). However, the adenovirus-5 vaccine alone (AdCA) failed to induce protection despite eliciting cellular responses that were often higher than those induced by DNA/Ad. Here we determined the effect of CHMI on pre-CHMI cellular and antibody responses against CSP and AMA1 expressed as fold-changes in activities. Generally, in the DNA/Ad trial, CHMI caused pre-CHMI ELISpot IFN-γ and CD8+ T cell IFN-γ responses of the protected subjects to fall but among non-protected subjects, CHMI caused rises of pre-CHMI ELISpot IFN-γ but falls of CD8+ T cell IFN-γ responses. In contrast in the AdCA trial, CHMI caused both pre-CHMI ELISpot IFN-γ and CD8+ T cell IFN-γ responses of the AdCA subjects to fall. We suggest that the falls in activities are due to migration of peripheral CD8+ T cells to the liver in response to developing liver stage parasites, and this fall, in the DNA/Ad trial, is masked in ELISpot responses of the non-protected subjects by rises in other immune cell types. In addition, CHMI caused falls in antibody activities of protected subjects, but rises in non-protected subjects in both trials to CSP, and dramatically in the AdCA trial to AMA1, reaching 380 μg/ml that is probably due to boosting by transient blood stage infection before chloroquine treatment. Taken together, these results further define differences in cellular responses between DNA/Ad and AdCA trials, and suggest that natural transmission may boost responses induced by these malaria vaccines especially when protection is not achieved.
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Affiliation(s)
- Martha Sedegah
- a Naval Medical Research Center ; Silver Spring , MD USA
| | | | - Fouzia Farooq
- a Naval Medical Research Center ; Silver Spring , MD USA
| | | | - Maria Belmonte
- a Naval Medical Research Center ; Silver Spring , MD USA
| | - Jun Huang
- a Naval Medical Research Center ; Silver Spring , MD USA
| | - Esteban Abot
- a Naval Medical Research Center ; Silver Spring , MD USA
| | - Keith Limbach
- a Naval Medical Research Center ; Silver Spring , MD USA
| | - Ilin Chuang
- a Naval Medical Research Center ; Silver Spring , MD USA
| | - Cindy Tamminga
- a Naval Medical Research Center ; Silver Spring , MD USA
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15
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Dumoulin PC, Trop SA, Ma J, Zhang H, Sherman MA, Levitskaya J. Flow Cytometry Based Detection and Isolation of Plasmodium falciparum Liver Stages In Vitro. PLoS One 2015; 10:e0129623. [PMID: 26070149 PMCID: PMC4466555 DOI: 10.1371/journal.pone.0129623] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 05/11/2015] [Indexed: 11/19/2022] Open
Abstract
Malaria, the disease caused by Plasmodium parasites, remains a major global health burden. The liver stage of Plasmodium falciparum infection is a leading target for immunological and pharmacological interventions. Therefore, novel approaches providing specific detection and isolation of live P. falciparum exoerythrocytic forms (EEFs) are warranted. Utilizing a recently generated parasite strain expressing green fluorescent protein (GFP) we established a method which, allows for detection and isolation of developing live P. falciparum liver stages by flow cytometry. Using this technique we compared the susceptibility of five immortalized human hepatocyte cell lines and primary hepatocyte cultures from three donors to infection by P. falciparum sporozoites. Here, we show that EEFs can be detected and isolated from in vitro infected cultures of the HC-04 cell line and primary human hepatocytes. We confirmed the presence of developing parasites in sorted live human hepatocytes and characterized their morphology by fluorescence microscopy. Finally, we validated the practical applications of our approach by re-examining the importance of host ligand CD81 for hepatocyte infection by P. falciparum sporozoites in vitro and assessment of the inhibitory activity of anti-sporozoite antibodies. This methodology provides us with the tools to study both, the basic biology of the P. falciparum liver stage and the effects of host-derived factors on the development of P. falciparum EEFs.
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Affiliation(s)
- Peter C. Dumoulin
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, United States of America
| | - Stefanie A. Trop
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, United States of America
| | - Jinxia Ma
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, United States of America
| | - Hao Zhang
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, United States of America
| | - Matthew A. Sherman
- Triangle Research Labs, 6 Davis Drive, Durham, NC, 27709, United States of America
| | - Jelena Levitskaya
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, United States of America
- * E-mail:
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Khan IA. CD8+ T cell immune response against non-viral pathogens. Semin Immunopathol 2015; 37:209-10. [PMID: 25944515 DOI: 10.1007/s00281-015-0489-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 04/06/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Imtiaz A Khan
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University, Washington, DC, 20037, USA,
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Radtke AJ, Tse SW, Zavala F. From the draining lymph node to the liver: the induction and effector mechanisms of malaria-specific CD8+ T cells. Semin Immunopathol 2015; 37:211-20. [PMID: 25917387 PMCID: PMC5600878 DOI: 10.1007/s00281-015-0479-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/15/2015] [Indexed: 10/23/2022]
Abstract
Parasitic protozoa cause considerable disease in humans and, due to their intracellular life cycle, induce robust CD8(+) T cell responses. A greater understanding of the factors that promote and maintain CD8(+) T cell-mediated immunity against these pathogens is likely needed for the development of effective vaccines. Immunization with radiation-attenuated sporozoites, the infectious stage of the malaria parasite transmitted by mosquitoes, is an excellent model to study these questions as CD8(+) T cells specific for a single epitope can completely eliminate parasite infection in the liver. Furthermore, live, radiation-attenuated parasites represent the "gold standard" for malaria vaccination. Here, we will highlight recent studies aimed at understanding the factors required for the induction, recruitment, and maintenance of effector and memory CD8(+) T cells against malaria liver stages.
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Affiliation(s)
- Andrea J. Radtke
- Lymphocyte Biology Section, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sze-Wah Tse
- Program in Cellular and Molecular Medicine of Children’s Hospital Boston, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Fidel Zavala
- Johns Hopkins Malaria Research Institute and Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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18
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Hojo-Souza NS, Pereira DB, Passos LSA, Gazzinelli-Guimarães PH, Cardoso MS, Tada MS, Zanini GM, Bartholomeu DC, Fujiwara RT, Bueno LL. Phenotypic profiling of CD8(+) T cells during Plasmodium vivax blood-stage infection. BMC Infect Dis 2015; 15:35. [PMID: 25636730 PMCID: PMC4329216 DOI: 10.1186/s12879-015-0762-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 01/15/2015] [Indexed: 12/27/2022] Open
Abstract
Background For a long time, the role of CD8+ T cells in blood-stage malaria was not considered important because erythrocytes do not express major histocompatibility complex (MHC) class I proteins. While recent evidences suggest that CD8+ T cells may play an important role during the erythrocytic phase of infection by eliminating parasites, CD8+ T cells might also contribute to modulate the host response through production of regulatory cytokines. Thus, the role of CD8+ T cells during blood-stage malaria is unclear. Here, we report the phenotypic profiling of CD8+ T cells subsets from patients with uncomplicated symptomatic P. vivax malaria. Methods Blood samples were collected from 20 Plasmodium vivax-infected individuals and 12 healthy individuals. Immunophenotyping was conducted by flow cytometry. Plasma levels of IFN-γ, TNF-α and IL-10 were determined by ELISA/CBA. Unpaired t-test or Mann–Whitney test was used depending on the data distribution. Results P. vivax-infected subjects had lower percentages and absolute numbers of CD8+CD45RA+ and CD8+CD45RO+ T cells when compared to uninfected individuals (p ≤ 0.0002). A significantly lower absolute number of circulating CD8+CD45+CCR7+ cells (p = 0.002) was observed in P. vivax-infected individuals indicating that infection reduces the number of central memory T cells. Cytokine expression was significantly reduced in the naïve T cells from infected individuals compared with negative controls, as shown by lower numbers of IFN-γ+ (p = 0.001), TNF-α+ (p < 0.0001) and IL-10+ (p < 0.0001) CD8+ T cells. Despite the reduction in the number of CD8+ memory T cells producing IFN-γ (p < 0.0001), P. vivax-infected individuals demonstrated a significant increase in memory CD8+TNF-α+ (p = 0.016) and CD8+IL-10+ (p = 0.004) cells. Positive correlations were observed between absolute numbers of CD8+IL-10+ and numbers of CD8+IFN-γ+ (p < 0.001) and CD8+TNF-α+ T cells (p ≤ 0.0001). Finally, an increase in the plasma levels of TNF-α (p = 0.017) and IL-10 (p = 0.006) and a decrease in the IFN-γ plasma level (p <0.0001) were observed in the P. vivax-infected individuals. Conclusions P. vivax infection reduces the numbers of different subsets of CD8+ T cells, particularly the memory cells, during blood-stage of infection and enhances the number of CD8+ memory T cells expressing IL-10, which positively correlates with the number of cells expressing TNF-α and IFN-γ. Electronic supplementary material The online version of this article (doi:10.1186/s12879-015-0762-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Natália Satchiko Hojo-Souza
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | | | - Lívia Silva Araújo Passos
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | - Pedro Henrique Gazzinelli-Guimarães
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | - Mariana Santos Cardoso
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | | | - Graziela Maria Zanini
- Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Daniella Castanheira Bartholomeu
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | - Ricardo Toshio Fujiwara
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
| | - Lilian Lacerda Bueno
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
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Sacks DL. Vaccines against tropical parasitic diseases: a persisting answer to a persisting problem. Nat Immunol 2014; 15:403-5. [PMID: 24747701 PMCID: PMC4814932 DOI: 10.1038/ni.2853] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Live and live-attenuated whole organism vaccines against Plasmodium falciparum malaria and cutaneous leishmaniasis due to Leishmania major remain the most uniformly effective vaccines against human parasitic diseases. These vaccines are discussed in terms of the nature of the T cell populations that mediate the strong and durable localized immunity to these infections, and the requirement for persisting antigen to generate and maintain the protective response. The difficulties in developing subunit vaccines that fulfill this requirement argue that despite their own formidable problems in manufacture and delivery, live and live- attenuated whole organism vaccines against human parasitic diseases should be vigorously pursued.
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Affiliation(s)
- David L Sacks
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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20
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Stanisic DI, Barry AE, Good MF. Escaping the immune system: How the malaria parasite makes vaccine development a challenge. Trends Parasitol 2013; 29:612-22. [DOI: 10.1016/j.pt.2013.10.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/01/2013] [Accepted: 10/01/2013] [Indexed: 10/26/2022]
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Ma J, Trop S, Baer S, Rakhmanaliev E, Arany Z, Dumoulin P, Zhang H, Romano J, Coppens I, Levitsky V, Levitskaya J. Dynamics of the major histocompatibility complex class I processing and presentation pathway in the course of malaria parasite development in human hepatocytes: implications for vaccine development. PLoS One 2013; 8:e75321. [PMID: 24086507 PMCID: PMC3783408 DOI: 10.1371/journal.pone.0075321] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 08/12/2013] [Indexed: 12/15/2022] Open
Abstract
Control of parasite replication exerted by MHC class I restricted CD8+ T-cells in the liver is critical for vaccination-induced protection against malaria. While many intracellular pathogens subvert the MHC class I presentation machinery, its functionality in the course of malaria replication in hepatocytes has not been characterized. Using experimental systems based on specific identification, isolation and analysis of human hepatocytes infected with P. berghei ANKA GFP or P. falciparum 3D7 GFP sporozoites we demonstrated that molecular components of the MHC class I pathway exhibit largely unaltered expression in malaria-infected hepatocytes until very late stages of parasite development. Furthermore, infected cells showed no obvious defects in their capacity to upregulate expression of different molecular components of the MHC class I machinery in response to pro-inflammatory lymphokines or trigger direct activation of allo-specific or peptide-specific human CD8+ T-cells. We further demonstrate that ectopic expression of circumsporozoite protein does not alter expression of critical genes of the MHC class I pathway and its response to pro-inflammatory cytokines. In addition, we identified supra-cellular structures, which arose at late stages of parasite replication, possessed the characteristic morphology of merosomes and exhibited nearly complete loss of surface MHC class I expression. These data have multiple implications for our understanding of natural T-cell immunity against malaria and may promote development of novel, efficient anti-malaria vaccines overcoming immune escape of the parasite in the liver.
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Affiliation(s)
- Jinxia Ma
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Stefanie Trop
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Samantha Baer
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Elian Rakhmanaliev
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Zita Arany
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Peter Dumoulin
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Hao Zhang
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Julia Romano
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Isabelle Coppens
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Victor Levitsky
- Department of Oncology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jelena Levitskaya
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
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Innate recognition of malarial parasites by mammalian hosts. Int J Parasitol 2012; 42:557-66. [DOI: 10.1016/j.ijpara.2012.04.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 04/11/2012] [Accepted: 04/13/2012] [Indexed: 12/22/2022]
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