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Hickey BW, Lumsden JM, Reyes S, Sedegah M, Hollingdale MR, Freilich DA, Luke TC, Charoenvit Y, Goh LM, Berzins MP, Bebris L, Sacci JB, De La Vega P, Wang R, Ganeshan H, Abot EN, Carucci DJ, Doolan DL, Brice GT, Kumar A, Aguiar J, Nutman TB, Leitman SF, Hoffman SL, Epstein JE, Richie TL. Mosquito bite immunization with radiation-attenuated Plasmodium falciparum sporozoites: safety, tolerability, protective efficacy and humoral immunogenicity. Malar J 2016; 15:377. [PMID: 27448805 PMCID: PMC4957371 DOI: 10.1186/s12936-016-1435-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 07/09/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In this phase 1 clinical trial, healthy adult, malaria-naïve subjects were immunized with radiation-attenuated Plasmodium falciparum sporozoites (PfRAS) by mosquito bite and then underwent controlled human malaria infection (CHMI). The PfRAS model for immunization against malaria had previously induced >90 % sterile protection against homologous CHMI. This study was to further explore the safety, tolerability and protective efficacy of the PfRAS model and to provide biological specimens to characterize protective immune responses and identify protective antigens in support of malaria vaccine development. METHODS Fifty-seven subjects were screened, 41 enrolled and 30 received at least one immunization. The true-immunized subjects received PfRAS via mosquito bite and the mock-immunized subjects received mosquito bites from irradiated uninfected mosquitoes. Sera and peripheral blood mononuclear cells (PBMCs) were collected before and after PfRAS immunizations. RESULTS Immunization with PfRAS was generally safe and well tolerated, and repeated immunization via mosquito bite did not appear to increase the risk or severity of AEs. Local adverse events (AEs) of true-immunized and mock-immunized groups consisted of erythaema, papules, swelling, and induration and were consistent with reactions from mosquito bites seen in nature. Two subjects, one true- and one mock-immunized, developed large local reactions that completely resolved, were likely a result of mosquito salivary antigens, and were withdrawn from further participation as a safety precaution. Systemic AEs were generally rare and mild, consisting of headache, myalgia, nausea, and low-grade fevers. Two true-immunized subjects experienced fever, malaise, myalgia, nausea, and rigours approximately 16 h after immunization. These symptoms likely resulted from pre-formed antibodies interacting with mosquito salivary antigens. Ten subjects immunized with PfRAS underwent CHMI and five subjects (50 %) were sterilely protected and there was a significant delay to parasitaemia in the other five subjects. All ten subjects developed humoral immune responses to whole sporozoites and to the circumsporozoite protein prior to CHMI, although the differences between protected and non-protected subjects were not statistically significant for this small sample size. CONCLUSIONS The protective efficacy of this clinical trial (50 %) was notably less than previously reported (>90 %). This may be related to differences in host genetics or the inherent variability in mosquito biting behavior and numbers of sporozoites injected. Differences in trial procedures, such as the use of leukapheresis prior to CHMI and of a longer interval between the final immunization and CHMI in these subjects compared to earlier trials, may also have reduced protective efficacy. This trial has been retrospectively registered at ISRCTN ID 17372582, May 31, 2016.
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Affiliation(s)
- Bradley W. Hickey
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Joanne M. Lumsden
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Sharina Reyes
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Martha Sedegah
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Michael R. Hollingdale
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Daniel A. Freilich
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas C. Luke
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Yupin Charoenvit
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Lucy M. Goh
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Mara P. Berzins
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Lolita Bebris
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - John B. Sacci
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Patricia De La Vega
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Ruobing Wang
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Harini Ganeshan
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Esteban N. Abot
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD USA
| | - Daniel J. Carucci
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Denise L. Doolan
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Gary T. Brice
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Anita Kumar
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Joao Aguiar
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas B. Nutman
- />Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Susan F. Leitman
- />Department of Transfusion Medicine, National Institutes of Health Clinical Center, Bethesda, MD USA
| | - Stephen L. Hoffman
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Sanaria Inc., Rockville, MD USA
| | - Judith E. Epstein
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
| | - Thomas L. Richie
- />US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD USA
- />Sanaria Inc., Rockville, MD USA
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Pichugin A, Steers N, De La Vega P, Zarling S, Chalom I, Krzych U. TAP-mediated processing of exoerythrocytic antigens is essential for protection induced with radiation-attenuated Plasmodium sporozoites. Eur J Immunol 2016; 46:885-96. [PMID: 26703789 DOI: 10.1002/eji.201545748] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 11/25/2015] [Accepted: 12/18/2015] [Indexed: 02/01/2023]
Abstract
MHC class I dependent CD8(+) T cells are essential for protection induced by radiation-attenuated Plasmodium sporozoites (RAS) in murine malaria models. Apart from the mechanism of activation of CD8(+) T cells specific for the circumsporozoite protein, the major sporozoite antigen (Ag), CD8(+) T cells specific for other exoerythrocytic Ags that have been shown to mediate protection have not been thoroughly investigated. Specifically, mechanisms of processing and presentation of exoerythrocytic Ags, which includes liver stage (LS) Ags, remain poorly understood. We hypothesize that as exogenous proteins, LS Ags are processed by mechanisms involving either the TAP-dependent phagosomal-to-cytosol or TAP-independent vacuolar pathway of cross-presentation. We used TAP-deficient mice to investigate whether LS Ag mediated induction of naïve CD8(+) T cells and their recall during sporozoite challenge occur by the TAP-dependent or TAP-independent pathways. On the basis of functional attributes, CD8(+) T cells were activated via the TAP-independent pathway during immunizations with Plasmodium berghei RAS; however, IFN-γ(+) CD8(+) T cells previously induced by P. berghei RAS in TAP-deficient mice failed to be recalled against sporozoite challenge and the mice became parasitemic. On the basis of these observations, we propose that TAP-associated Ag processing is indispensable for sterile protection induced with P. berghei RAS.
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Affiliation(s)
- Alexander Pichugin
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Nick Steers
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Patricia De La Vega
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Stasya Zarling
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Isaac Chalom
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Urszula Krzych
- Department of Cellular Immunology, Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
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Zhou Z, Todd CW, Wohlhueter RM, Price A, Xiao L, Schnake P, Bonner PC, Martin AM, Goldman IF, De La Vega P, Udhayakumar V, Lal AA. Development, Characterization and Immunogenicity of a Multi-Stage, MultivalentPlasmodium falciparumVaccine Antigen (FALVAC-1A) Expressed inEscherichia coli. Human Vaccines 2014; 2:14-23. [PMID: 17012909 DOI: 10.4161/hv.2.1.2437] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A synthetic multistage, multi-epitope Plasmodium falciparum malaria antigen (FALVAC-1A) was designed and evaluated in silico, and then the gene was constructed and expressed in Escherichia coli. The FALVAC-1A protein was purified by inclusion body isolation, followed by affinity and ion exchange chromatography. Although FALVAC-1A was a synthetic antigen, it folded to a specific, but as yet incompletely defined, molecular conformation that was stable and comparable from lot to lot. When formulated with four different adjuvants, FALVAC-1A was highly immunogenic in rabbits, inducing not only ELISA reactivity to the cognate antigen and most of its component epitopes, but also in vitro activity against P. falciparum parasites as demonstrated by inhibition of sporozoite invasion, antibody dependent cellular inhibition and the immunofluorescence assay.
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Affiliation(s)
- Zhiyong Zhou
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
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4
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Pichugin A, Steers N, De La Vega P, Krzych U. Although the induction of INF-γ+ CD8 T cells by radiation-attenuated Plasmodium berghei sporozoites is TAP-independent, the recall of protective effector CD8 T cells during infection requires TAP machinery (MPF6P.740). The Journal of Immunology 2014. [DOI: 10.4049/jimmunol.192.supp.195.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Multiple exposures of humans and laboratory rodents to radiation-attenuated Plasmodium sporozoites (γ-spz) induce sterile and long-lasting protection that is thought to be directed mainly to liver-stage antigens (LS-Ags). Although protection involves B cells and CD4 T cells, MHC class I-dependent liver IFN-γ+ CD8 T cells are the key effectors against LS-Ags. Recently several LS-Ags have been shown to induce protection in murine models; nevertheless, the mechanism of processing and presentation of LS-Ag to CD8 T cells has not been investigated. We tested liver CD8 T cell responses induced by Plasmodium berghei (Pb) γ-spz in TAP-/- mice to inquire whether processing/presentation of the exogenous LS-Ags was TAP-dependent or -independent. Immunization with Pb γ-spz induced proliferation and IFN-γ production by liver CD8 T cells. Also, TAP-/- CD8 T cells eliminated hepatocytes infected with Pb sporozoites in vitro. Despite these effector activities, Pb γ-spz immunized TAP-/- mice were not protected against sporozoite infection, mainly because liver CD8 T effector cells failed to produce IFN-γ in response to infectious sporozoite challenge. Our results demonstrate that although TAP-independent vacuolar pathway operates efficiently during immunization with γ-spz, the TAP-associated phagosomal-to-cytosol antigen processing mechanism appears to be required for effective recall of effector CD8 T cells during infection. The implications of these findings will be discussed.
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Affiliation(s)
- Alexander Pichugin
- 1Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD
| | - Nick Steers
- 1Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD
| | - Patricia De La Vega
- 1Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD
| | - Urszula Krzych
- 1Malaria Vaccine Branch, Walter Reed Army Institute of Research, Silver Spring, MD
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5
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Hobbs CV, Voza T, De La Vega P, Vanvliet J, Conteh S, Penzak SR, Fay MP, Anders N, Ilmet T, Li Y, Borkowsky W, Krzych U, Duffy PE, Sinnis P. HIV nonnucleoside reverse transcriptase inhibitors and trimethoprim-sulfamethoxazole inhibit plasmodium liver stages. J Infect Dis 2013; 206:1706-14. [PMID: 23125449 DOI: 10.1093/infdis/jis602] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Although nonnucleoside reverse transcriptase inhibitors (NNRTIs) are usually part of first-line treatment regimens for human immunodeficiency virus (HIV), their activity on Plasmodium liver stages remains unexplored. Additionally, trimethoprim-sulfamethoxazole (TMP-SMX), used for opportunistic infection prophylaxis in HIV-exposed infants and HIV-infected patients, reduces clinical episodes of malaria; however, TMP-SMX effect on Plasmodium liver stages requires further study. METHODS We characterized NNRTI and TMP-SMX effects on Plasmodium liver stages in vivo using Plasmodium yoelii. On the basis of these results, we conducted in vitro studies assessing TMP-SMX effects on the rodent parasites P. yoelii and Plasmodium berghei and on the human malaria parasite Plasmodium falciparum. RESULTS Our data showed NNRTI treatment modestly reduced P. yoelii liver stage parasite burden and minimally extended prepatent period. TMP-SMX administration significantly reduced liver stage parasite burden, preventing development of patent parasitemia in vivo. TMP-SMX inhibited development of rodent and P. falciparum liver stage parasites in vitro. CONCLUSIONS NNRTIs modestly affect liver stage Plasmodium parasites, whereas TMP-SMX prevents patent parasitemia. Because drugs that inhibit liver stages target parasites when they are present in lower numbers, these results may have implications for eradication efforts. Understanding HIV drug effects on Plasmodium liver stages will aid in optimizing treatment regimens for HIV-exposed and HIV-infected infected patients in malaria-endemic areas.
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Affiliation(s)
- Charlotte V Hobbs
- NIH/NIAID/Laboratory of Malaria Immunology and Vaccinology, Rockville, Maryland 20852, USA
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6
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Richie TL, Charoenvit Y, Wang R, Epstein JE, Hedstrom RC, Kumar S, Luke TC, Freilich DA, Aguiar JC, Sacci JB, Sedegah M, Nosek RA, De La Vega P, Berzins MP, Majam VF, Abot EN, Ganeshan H, Richie NO, Banania JG, Baraceros MFB, Geter TG, Mere R, Bebris L, Limbach K, Hickey BW, Lanar DE, Ng J, Shi M, Hobart PM, Norman JA, Soisson LA, Hollingdale MR, Rogers WO, Doolan DL, Hoffman SL. Clinical trial in healthy malaria-naïve adults to evaluate the safety, tolerability, immunogenicity and efficacy of MuStDO5, a five-gene, sporozoite/hepatic stage Plasmodium falciparum DNA vaccine combined with escalating dose human GM-CSF DNA. Hum Vaccin Immunother 2012; 8:1564-84. [PMID: 23151451 PMCID: PMC3601132 DOI: 10.4161/hv.22129] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
When introduced in the 1990s, immunization with DNA plasmids was considered potentially revolutionary for vaccine development, particularly for vaccines intended to induce protective CD8 T cell responses against multiple antigens. We conducted, in 1997−1998, the first clinical trial in healthy humans of a DNA vaccine, a single plasmid encoding Plasmodium falciparum circumsporozoite protein (PfCSP), as an initial step toward developing a multi-antigen malaria vaccine targeting the liver stages of the parasite. As the next step, we conducted in 2000–2001 a clinical trial of a five-plasmid mixture called MuStDO5 encoding pre-erythrocytic antigens PfCSP, PfSSP2/TRAP, PfEXP1, PfLSA1 and PfLSA3. Thirty-two, malaria-naïve, adult volunteers were enrolled sequentially into four cohorts receiving a mixture of 500 μg of each plasmid plus escalating doses (0, 20, 100 or 500 μg) of a sixth plasmid encoding human granulocyte macrophage-colony stimulating factor (hGM-CSF). Three doses of each formulation were administered intramuscularly by needle-less jet injection at 0, 4 and 8 weeks, and each cohort had controlled human malaria infection administered by five mosquito bites 18 d later. The vaccine was safe and well-tolerated, inducing moderate antigen-specific, MHC-restricted T cell interferon-γ responses but no antibodies. Although no volunteers were protected, T cell responses were boosted post malaria challenge. This trial demonstrated the MuStDO5 DNA and hGM-CSF plasmids to be safe and modestly immunogenic for T cell responses. It also laid the foundation for priming with DNA plasmids and boosting with recombinant viruses, an approach known for nearly 15 y to enhance the immunogenicity and protective efficacy of DNA vaccines.
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7
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Mikolajczak SA, Sacci JB, De La Vega P, Camargo N, VanBuskirk K, Krzych U, Cao J, Jacobs-Lorena M, Cowman AF, Kappe SHI. Disruption of the Plasmodium falciparum liver-stage antigen-1 locus causes a differentiation defect in late liver-stage parasites. Cell Microbiol 2011; 13:1250-60. [PMID: 21569184 DOI: 10.1111/j.1462-5822.2011.01617.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The malaria parasite Plasmodium falciparum infects humans and first targets the liver where liver-stage parasites undergo pre-erythrocytic replication. Liver-stage antigen-1 (LSA-1) is currently the only identified P. falciparum protein for which expression is restricted to liver stages. Yet, the importance of LSA-1 for liver-stage parasite development remains unknown. Here we deleted LSA-1 in the NF54 strain of P. falciparum and analysed the lsa-1(-) parasites throughout their life cycle. lsa-1(-) sporozoites had normal gliding motility and invasion into hepatocytes. Six days after infection of a hepatocytic cell line, lsa-1(-) parasites exhibited a moderate phenotype with an ~50% reduction of late liver-stage forms when compared with wild type. Strikingly, lsa-1(-) parasites growing in SCID/Alb-uPA mice with humanized livers showed a severe defect in late liver-stage differentiation and exo-erythrocytic merozoite formation 7 days after infection, a time point when wild-type parasites develop into mature merozoites. The lsa-1(-) parasites also showed aberrant liver-stage expression of key parasite proteins apical membrane antigen-1 and circumsporozoite protein. Our data show that LSA-1 plays a critical role during late liver-stage schizogony and is thus important in the parasite transition from the liver to blood. LSA-1 is the first P. falciparum protein identified to be required for this transitional stage of the parasite life cycle.
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8
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Bergmann-Leitner ES, Mease RM, De La Vega P, Savranskaya T, Polhemus M, Ockenhouse C, Angov E. Immunization with pre-erythrocytic antigen CelTOS from Plasmodium falciparum elicits cross-species protection against heterologous challenge with Plasmodium berghei. PLoS One 2010; 5:e12294. [PMID: 20808868 PMCID: PMC2924390 DOI: 10.1371/journal.pone.0012294] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Accepted: 07/29/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The Plasmodium protein Cell-traversal protein for ookinetes and sporozoites (CelTOS) plays an important role in cell traversal of host cells in both, mosquito and vertebrates, and is required for successful malaria infections. CelTOS is highly conserved among the Plasmodium species, suggesting an important functional role across all species. Therefore, targeting the immune response to this highly conserved protein and thus potentially interfering with its biological function may result in protection against infection even by heterologous species of Plasmodium. METHODOLOGY/PRINCIPAL FINDINGS To test this hypothesis, we developed a recombinant codon-harmonized P. falciparum CelTOS protein that can be produced to high yields in the E. coli expression system. Inbred Balb/c and outbred CD-1 mice were immunized with various doses of the recombinant protein adjuvanted with Montanide ISA 720 and characterized using in vitro and in vivo analyses. CONCLUSIONS/SIGNIFICANCE Immunization with PfCelTOS resulted in potent humoral and cellular immune responses and most importantly induced sterile protection against a heterologous challenge with P. berghei sporozoites in a proportion of both inbred and outbred mice. The biological activity of CelTOS-specific antibodies against the malaria parasite is likely linked to the impairment of sporozoite motility and hepatocyte infectivity. The results underscore the potential of this antigen as a pre-erythrocytic vaccine candidate and demonstrate for the first time a malaria vaccine that is cross-protective between species.
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Affiliation(s)
- Elke S Bergmann-Leitner
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
| | - Ryan M. Mease
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
| | - Patricia De La Vega
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
| | - Tatyana Savranskaya
- Division of Entomology, Walter Reed Army
Institute of Research, Silver Spring, Maryland, United States of
America
| | - Mark Polhemus
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
| | - Christian Ockenhouse
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
| | - Evelina Angov
- Division of Malaria Vaccine Development,
United States Military Malaria Vaccine Program, Walter Reed Army Institute of
Research, Silver Spring, Maryland, United States of America
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9
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Le Roch KG, Zhou Y, Blair PL, Grainger M, Moch JK, Haynes JD, De La Vega P, Holder AA, Batalov S, Carucci DJ, Winzeler EA. Discovery of gene function by expression profiling of the malaria parasite life cycle. Science 2003; 301:1503-8. [PMID: 12893887 DOI: 10.1126/science.1087025] [Citation(s) in RCA: 1013] [Impact Index Per Article: 48.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The completion of the genome sequence for Plasmodium falciparum, the species responsible for most malaria human deaths, has the potential to reveal hundreds of new drug targets and proteins involved in pathogenesis. However, only approximately 35% of the genes code for proteins with an identifiable function. The absence of routine genetic tools for studying Plasmodium parasites suggests that this number is unlikely to change quickly if conventional serial methods are used to characterize encoded proteins. Here, we use a high-density oligonucleotide array to generate expression profiles of human and mosquito stages of the malaria parasite's life cycle. Genes with highly correlated levels and temporal patterns of expression were often involved in similar functions or cellular processes.
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Affiliation(s)
- Karine G Le Roch
- Department of Cell Biology ICND202, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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