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Lu J, Hu Z, Jiang H, Wen Z, Li H, Li J, Zeng K, Xie Y, Chen H, Su XZ, Cai C, Yu X. Dual nature of type I interferon responses and feedback regulations by SOCS1 dictate malaria mortality. J Adv Res 2024:S2090-1232(24)00370-9. [PMID: 39181199 DOI: 10.1016/j.jare.2024.08.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 08/20/2024] [Accepted: 08/21/2024] [Indexed: 08/27/2024] Open
Abstract
INTRODUCTION Type I interferon (IFN-I, IFN-α/β), precisely controlled by multiple regulators, including suppressor of cytokine signaling 1 (SOCS1), is critical for host defense against pathogens. However, the impact of IFN-α/β on malaria parasite infections, beneficial or detrimental, remains controversial. OBJECTIVES The contradictory results are suspected to arise from differences in parasite species and host genetic backgrounds. To date, no prior study has employed a comparative approach utilizing two parasite models to investigate the underlying mechanisms of IFN-I response. Moreover, whether and how SOCS1 involves in the distinct IFN-α/β dynamics is still unclear. METHODS Here we perform single-cell RNA sequencing analyses (scRNA-seq) to dissect the dynamics of IFN-α/β responses against P. yoelii 17XL (17XL) and P. berghei ANKA (PbANKA) infections; conduct flow cytometry analysis and functional depletion to identify key cellular players induced by IFN-I; and establish mathematical models to explore the mechanisms underlying the differential IFN-I dynamics regulated by SOCS1. RESULTS 17XL stimulates an early protective but insufficient toll-like receptor 7 (TLR7)-interferon regulatory factor 7 (IRF7)-dependent IFN-α/β response, resulting in CD11ahiCD49dhiCD4+ T cell activation to enhance anti-malarial immunity. On the contrary, a late IFN-α/β induction through toll-like receptor 9 (TLR9)-IRF7/ stimulator of interferon genes (STING)- interferon regulatory factor 3 (IRF3) dependent pathways expands programmed cell death protein 1 (PD-1)+CD8+ T cells and impairs host immunity during PbANKA infection. Furthermore, functional assay and mathematical modeling show that SOCS1 significantly suppresses IFN-α/β production via negative feedback and incoherent feed-forward loops (I1-FFL). Additionally, differential activation patterns of various transcriptional factors (TFs) synergistically regulate the distinct IFN-I responses. CONCLUSION This study reveals the dual functions of IFN-I in anti-malarial immunity: Early IFN-α/β enhances immune responses against Plasmodium infection by promoting CD11ahiCD49dhiCD4+ T cell, while late IFN-α/β suppresses these response by expanding PD-1+CD8+ T cells. Moreover, both the SOCS1-related network motifs and TFs activation patterns contribute to determine distinct dynamics of IFN-I responses. Hence, our findings suggest therapies targeting SOCS1- or TFs-regulated IFN-I dynamics could be an efficacious approach for preventing malaria and enhancing vaccine efficacy.
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Affiliation(s)
- Jiansen Lu
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Zhiqiang Hu
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China; Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Institute of Translational Medicine, Zhejiang University School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Huaji Jiang
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Zebin Wen
- Guangdong Provincial Key Lab of Single Cell Technology and Application, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Hongyu Li
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Jian Li
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361000, China
| | - Ke Zeng
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Yingchao Xie
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Huadan Chen
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Xin-Zhuan Su
- Malaria Functional Genomics Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Chunmei Cai
- Research Center for High Altitude Medicine, School of Medical, Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province, Qinghai University, Xining, Qinghai 810000, China.
| | - Xiao Yu
- Department of Joint Surgery, the Fifth Affiliated Hospital of Southern Medical University, Department of Immunology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China; Guangdong Provincial Key Lab of Single Cell Technology and Application, Southern Medical University, Guangzhou, Guangdong 510515, China; Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong 510000, China.
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Ghosh A, Mishra A, Devi R, Narwal SK, Nirdosh, Srivastava PN, Mishra S. A Micronemal Protein, Scot1, Is Essential for Apicoplast Biogenesis and Liver Stage Development in Plasmodium berghei. ACS Infect Dis 2024; 10:3013-3025. [PMID: 39037752 DOI: 10.1021/acsinfecdis.4c00362] [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] [Indexed: 07/23/2024]
Abstract
Plasmodium sporozoites invade hepatocytes, transform into liver stages, and replicate into thousands of merozoites that infect erythrocytes and cause malaria. Proteins secreted from micronemes play an essential role in hepatocyte invasion, and unneeded micronemes are subsequently discarded for replication. The liver-stage parasites are potent immunogens that prevent malarial infection. Late liver stage-arresting genetically attenuated parasites (GAPs) exhibit greater protective efficacy than early GAP. However, the number of late liver-stage GAPs for generating GAPs with multiple gene deletions is limited. Here, we identified Scot1 (Sporozoite Conserved Orthologous Transcript 1), which was previously shown to be upregulated in sporozoites, and by endogenous tagging with mCherry, we demonstrated that it is expressed in the sporozoite and liver stages in micronemes. Using targeted gene deletion in Plasmodium berghei, we showed that Scot1 is essential for late liver-stage development. Scot1 KO sporozoites grew normally into liver stages but failed to initiate blood-stage infection in mice due to impaired apicoplast biogenesis and merozoite formation. Bioinformatic studies suggested that Scot1 is a metal-small-molecule carrier protein. Remarkably, supplementation with metals in the culture of infected Scot1 KO cells did not rescue their phenotype. Immunization with Scot1 KO sporozoites in C57BL/6 mice confers protection against malaria via infection. These proof-of-concept studies will enable the generation of P. falciparum Scot1 mutants that could be exploited to generate GAP malaria vaccines.
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Affiliation(s)
- Ankit Ghosh
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Akancha Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Raksha Devi
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Sunil Kumar Narwal
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Nirdosh
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Pratik Narain Srivastava
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Satish Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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Narwal SK, Mishra A, Devi R, Ghosh A, Choudhary HH, Mishra S. Stearoyl-CoA desaturase regulates organelle biogenesis and hepatic merozoite formation in Plasmodium berghei. Mol Microbiol 2024; 121:940-953. [PMID: 38419272 DOI: 10.1111/mmi.15246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 02/13/2024] [Accepted: 02/16/2024] [Indexed: 03/02/2024]
Abstract
Plasmodium is an obligate intracellular parasite that requires intense lipid synthesis for membrane biogenesis and survival. One of the principal membrane components is oleic acid, which is needed to maintain the membrane's biophysical properties and fluidity. The malaria parasite can modify fatty acids, and stearoyl-CoA Δ9-desaturase (Scd) is an enzyme that catalyzes the synthesis of oleic acid by desaturation of stearic acid. Scd is dispensable in P. falciparum blood stages; however, its role in mosquito and liver stages remains unknown. We show that P. berghei Scd localizes to the ER in the blood and liver stages. Disruption of Scd in the rodent malaria parasite P. berghei did not affect parasite blood stage propagation, mosquito stage development, or early liver-stage development. However, when Scd KO sporozoites were inoculated intravenously or by mosquito bite into mice, they failed to initiate blood-stage infection. Immunofluorescence analysis revealed that organelle biogenesis was impaired and merozoite formation was abolished, which initiates blood-stage infections. Genetic complementation of the KO parasites restored merozoite formation to a level similar to that of WT parasites. Mice immunized with Scd KO sporozoites confer long-lasting sterile protection against infectious sporozoite challenge. Thus, the Scd KO parasite is an appealing candidate for inducing protective pre-erythrocytic immunity and hence its utility as a GAP.
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Affiliation(s)
- Sunil Kumar Narwal
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Akancha Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Raksha Devi
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Ankit Ghosh
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Hadi Hasan Choudhary
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Satish Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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Williams KL, Guerrero S, Flores-Garcia Y, Kim D, Williamson KS, Siska C, Smidt P, Jepson SZ, Li K, Dennison SM, Mathis-Torres S, Chen X, Wille-Reece U, MacGill RS, Walker M, Jongert E, King CR, Ockenhouse C, Glanville J, Moon JE, Regules JA, Tan YC, Cavet G, Lippow SM, Robinson WH, Dutta S, Tomaras GD, Zavala F, Ketchem RR, Emerling DE. A candidate antibody drug for prevention of malaria. Nat Med 2024; 30:117-129. [PMID: 38167935 PMCID: PMC10803262 DOI: 10.1038/s41591-023-02659-z] [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: 03/10/2023] [Accepted: 10/20/2023] [Indexed: 01/05/2024]
Abstract
Over 75% of malaria-attributable deaths occur in children under the age of 5 years. However, the first malaria vaccine recommended by the World Health Organization (WHO) for pediatric use, RTS,S/AS01 (Mosquirix), has modest efficacy. Complementary strategies, including monoclonal antibodies, will be important in efforts to eradicate malaria. Here we characterize the circulating B cell repertoires of 45 RTS,S/AS01 vaccinees and discover monoclonal antibodies for development as potential therapeutics. We generated >28,000 antibody sequences and tested 481 antibodies for binding activity and 125 antibodies for antimalaria activity in vivo. Through these analyses we identified correlations suggesting that sequences in Plasmodium falciparum circumsporozoite protein, the target antigen in RTS,S/AS01, may induce immunodominant antibody responses that limit more protective, but subdominant, responses. Using binding studies, mouse malaria models, biomanufacturing assessments and protein stability assays, we selected AB-000224 and AB-007088 for advancement as a clinical lead and backup. We engineered the variable domains (Fv) of both antibodies to enable low-cost manufacturing at scale for distribution to pediatric populations, in alignment with WHO's preferred product guidelines. The engineered clone with the optimal manufacturing and drug property profile, MAM01, was advanced into clinical development.
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Affiliation(s)
| | | | - Yevel Flores-Garcia
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Dongkyoon Kim
- Atreca, Inc., San Carlos, CA, USA
- Initium Therapeutics, Inc., Natick, MA, USA
| | | | | | | | | | - Kan Li
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
| | - S Moses Dennison
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
| | - Shamika Mathis-Torres
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | - Ulrike Wille-Reece
- BioNTech US, Inc., Cambridge, MA, USA
- PATH Center for Vaccine Innovation and Access, Washington DC, USA
| | | | | | | | - C Richter King
- PATH Center for Vaccine Innovation and Access, Washington DC, USA
| | | | | | - James E Moon
- Center for Enabling Capabilities, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jason A Regules
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Yann Chong Tan
- Atreca, Inc., San Carlos, CA, USA
- Nuevocor Pte. Ltd, Singapore, Singapore
| | - Guy Cavet
- Atreca, Inc., San Carlos, CA, USA
- Paramune, Inc., San Carlos, CA, USA
| | | | - William H Robinson
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Georgia D Tomaras
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
- Departments of Immunology, Molecular Genetics and Microbiology, Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Browne DJ, Kelly AM, Brady J, Proietti C, Sarathkumara YD, Pattinson DJ, Doolan DL. Evaluating the stability of host-reference gene expression and simultaneously quantifying parasite burden and host immune responses in murine malaria. Sci Rep 2023; 13:21071. [PMID: 38030676 PMCID: PMC10687243 DOI: 10.1038/s41598-023-48066-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023] Open
Abstract
The efficacy of pre-erythrocytic stage malaria antigens or vaccine platforms is routinely assessed in murine models challenged with Plasmodium sporozoites. Relative liver-stage parasite burden is quantified using reverse transcription quantitative PCR (RTqPCR), which relies on constitutively expressed endogenous control reference genes. However, the stability of host-reference gene expression for RTqPCR analysis following Plasmodium challenge and immunization has not been systematically evaluated. Herein, we evaluated the stability of expression of twelve common RTqPCR reference genes in a murine model of Plasmodium yoelii sporozoite challenge and DNA-adenovirus IV 'Prime-Target' immunization. Significant changes in expression for six of twelve reference genes were shown by one-way ANOVA, when comparing gene expression levels among challenge, immunized, and naïve mice groups. These changes were attributed to parasite challenge or immunization when comparing group means using post-hoc Bonferroni corrected multiple comparison testing. Succinate dehydrogenase (SDHA) and TATA-binding protein (TBP) were identified as stable host-reference genes suitable for relative RTqPCR data normalisation, using the RefFinder package. We defined a robust threshold of 'partial-protection' with these genes and developed a strategy to simultaneously quantify matched host parasite burden and cytokine responses following immunisation or challenge. This is the first report systematically identifying reliable host reference genes for RTqPCR analysis following Plasmodium sporozoite challenge. A robust RTqPCR protocol incorporating reliable reference genes which enables simultaneous analysis of host whole-liver cytokine responses and parasite burden will significantly standardise and enhance results between international malaria vaccine efficacy studies.
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Affiliation(s)
- Daniel J Browne
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia
| | - Ashton M Kelly
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia
- Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, QLD, 4072, Australia
| | - Jamie Brady
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia
| | - Carla Proietti
- Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, QLD, 4072, Australia
| | - Yomani D Sarathkumara
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia
- Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, QLD, 4072, Australia
| | - David J Pattinson
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia
| | - Denise L Doolan
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia.
- Institute for Molecular Bioscience, The University of Queensland, 306 Carmody Rd, St Lucia, QLD, 4072, Australia.
- Centre for Tropical Bioinformatics and Molecular Biology, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, 4870, Australia.
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Nicholas J, Kolli SK, Subramani PA, De SL, Ogbondah MM, Barnes SJ, Ntumngia FB, Adams JH. Comparative analyses of functional antibody-mediated inhibition with anti-circumsporozoite monoclonal antibodies against transgenic Plasmodium berghei. Malar J 2023; 22:335. [PMID: 37936181 PMCID: PMC10629016 DOI: 10.1186/s12936-023-04765-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/24/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Acquired functional inhibitory antibodies are one of several humoral immune mechanisms used to neutralize foreign pathogens. In vitro bioassays are useful tools for quantifying antibody-mediated inhibition and evaluating anti-parasite immune antibodies. However, a gap remains in understanding of how antibody-mediated inhibition in vitro translates to inhibition in vivo. In this study, two well-characterized transgenic Plasmodium berghei parasite lines, PbmCh-luc and Pb-PfCSP(r), and murine monoclonal antibodies (mAbs) specific to P. berghei and Plasmodium falciparum circumsporozoite protein (CSP), 3D11 and 2A10, respectively, were used to evaluate antibody-mediated inhibition of parasite development in both in vitro and in vivo functional assays. METHODS IC50 values of mAbs were determined using an established inhibition of liver-stage development assay (ILSDA). For the in vivo inhibition assay, mice were passively immunized by transfer of the mAbs and subsequently challenged with 5.0 × 103 sporozoites via tail vein injection. The infection burden in both assays was quantified by luminescence and qRT-PCR of P. berghei 18S rRNA normalized to host GAPDH. RESULTS The IC50 values quantified by relative luminescence of mAbs 3D11 and 2A10 were 0.396 µg/ml and 0.093 µg/ml, respectively, against transgenic lines in vitro. Using the highest (> 90%) inhibitory antibody concentrations in a passive transfer, an IC50 of 233.8 µg/ml and 181.5 µg/ml for mAbs 3D11 and 2A10, respectively, was observed in vivo. At 25 µg (250 µg/ml), the 2A10 antibody significantly inhibited liver burden in mice compared to control. Additionally, qRT-PCR of P. berghei 18S rRNA served as a secondary validation of liver burden quantification. CONCLUSIONS Results from both experimental models, ILSDA and in vivo challenge, demonstrated that increased concentrations of the homologous anti-CSP repeat mAbs increased parasite inhibition. However, differences in antibody IC50 values between parasite lines did not allow a direct correlation between the inhibition of sporozoite invasion in vitro by ILSDA and the inhibition of mouse liver stage burden. Further studies are needed to establish the conditions for confident predictions for the in vitro ILSDA to be a predictor of in vivo outcomes using this model system.
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Affiliation(s)
- Justin Nicholas
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Surendra Kumar Kolli
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Pradeep Annamalai Subramani
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Sai Lata De
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
- Department of Infectious Disease & Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Madison M Ogbondah
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Samantha J Barnes
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Francis Babila Ntumngia
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - John H Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA.
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Mishra A, Varshney A, Mishra S. Regulation of Atg8 membrane deconjugation by cysteine proteases in the malaria parasite Plasmodium berghei. Cell Mol Life Sci 2023; 80:344. [PMID: 37910326 PMCID: PMC11073460 DOI: 10.1007/s00018-023-05004-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 09/22/2023] [Accepted: 10/16/2023] [Indexed: 11/03/2023]
Abstract
During macroautophagy, the Atg8 protein is conjugated to phosphatidylethanolamine (PE) in autophagic membranes. In Apicomplexan parasites, two cysteine proteases, Atg4 and ovarian tumor unit (Otu), have been identified to delipidate Atg8 to release this protein from membranes. Here, we investigated the role of cysteine proteases in Atg8 conjugation and deconjugation and found that the Plasmodium parasite consists of both activities. We successfully disrupted the genes individually; however, simultaneously, they were refractory to deletion and essential for parasite survival. Mutants lacking Atg4 and Otu showed normal blood and mosquito stage development. All mice infected with Otu KO sporozoites became patent; however, Atg4 KO sporozoites either failed to establish blood infection or showed delayed patency. Through in vitro and in vivo analysis, we found that Atg4 KO sporozoites invade and normally develop into early liver stages. However, nuclear and organelle differentiation was severely hampered during late stages and failed to mature into hepatic merozoites. We found a higher level of Atg8 in Atg4 KO parasites, and the deconjugation of Atg8 was hampered. We confirmed Otu localization on the apicoplast; however, parasites lacking Otu showed no visible developmental defects. Our data suggest that Atg4 is the primary deconjugating enzyme and that Otu cannot replace its function completely because it cleaves the peptide bond at the N-terminal side of glycine, thereby irreversibly inactivating Atg8 during its recycling. These findings highlight a role for the Atg8 deconjugation pathway in organelle biogenesis and maintenance of the homeostatic cellular balance.
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Affiliation(s)
- Akancha Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Aastha Varshney
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Satish Mishra
- Division of Molecular Microbiology and Immunology, CSIR-Central Drug Research Institute, Lucknow, 226031, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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Nasir G, Sinnis P. Transport of antibody into the skin is only partially dependent upon the neonatal Fc-receptor. PLoS One 2023; 18:e0273960. [PMID: 37093800 PMCID: PMC10124839 DOI: 10.1371/journal.pone.0273960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 03/30/2023] [Indexed: 04/25/2023] Open
Abstract
The dermis is the portal of entry for most vector-transmitted pathogens, making the host's immune response at this site critical in mitigating the magnitude of infection. For malaria, antibody-mediated neutralization of Plasmodium parasites in the dermis was recently demonstrated. However, surprisingly little is known about the mechanisms that govern antibody transport into the skin. Since the neonatal Fc receptor (FcRn) has been shown to transcytose IgG into various tissues, we sought to understand its contribution to IgG transport into the skin and antibody-mediated inhibition of Plasmodium parasites following mosquito bite inoculation. Using confocal imaging, we show that the transport of an anti-Langerin mAb into the skin occurs but is only partially reduced in mice lacking FcRn. To understand the relevance of FcRn in the context of malaria infection, we use the rodent parasite Plasmodium berghei and show that passively-administered anti-malarial antibody in FcRn deficient mice, does not reduce parasite burden to the same extent as previously observed in wildtype mice. Overall, our data suggest that FcRn plays a role in the transport of IgG into the skin but is not the major driver of IgG transport into this tissue. These findings have implications for the rational design of antibody-based therapeutics for malaria as well as other vector-transmitted pathogens.
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Affiliation(s)
- Gibran Nasir
- Johns Hopkins Malaria Institute and Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Photini Sinnis
- Johns Hopkins Malaria Institute and Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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Silveira ELVD, Rai U, Bonezi V, Zárate-Bladés CR, Claser C. CCR6 expression reduces mouse survival upon malarial challenge with Plasmodium berghei NK65 strain. Mem Inst Oswaldo Cruz 2022; 117:e210287. [PMID: 35730803 PMCID: PMC9208320 DOI: 10.1590/0074-02760210287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 04/26/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND It has been demonstrated that proteins expressed by liver-stage Plasmodium parasites can inhibit the translocation of transcription factors to the nucleus of different cells. This process would hinder the expression of immune genes, such as the CCL20 chemokine. OBJECTIVE Since CCR6 is the only cognate receptor for CCL20, we investigated the importance of this chemokine-receptor axis against rodent malaria. METHODS CCR6-deficient (KO) and wild-type (WT) C57BL/6 mice were challenged with Plasmodium berghei (Pb) NK65 sporozoites or infected red blood cells (iRBCs). Liver parasitic cDNA, parasitemia and serum cytokine concentrations were respectively evaluated through reverse transcription-polymerase chain reaction (RT-PCR), staining thin-blood smears with Giemsa solution, and enzyme-linked immunosorbent assay (ELISA). FINDINGS Although the sporozoite challenges yielded similar liver parasitic cDNA and parasitemia, KO mice presented a prolonged survival than WT mice. After iRBC challenges, KO mice kept displaying higher survival rates as well as a decreased IL-12 p70 concentration in the serum than WT mice. CONCLUSION Our data suggest that malaria triggered by PbNK65 liver- or blood-stage forms elicit a pro-inflammatory environment that culminates with a decreased survival of infected C57BL/6 mice.
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Affiliation(s)
- Eduardo Lani Volpe da Silveira
- New York University School of Medicine, Department of Pathology, Michael Heidelberg Division of Immunology, New York, NY, United States of America
| | - Urvashi Rai
- New York University School of Medicine, Department of Pathology, Michael Heidelberg Division of Immunology, New York, NY, United States of America
| | - Vivian Bonezi
- Universidade de São Paulo, Faculdade de Ciências Farmacêuticas, Departamento de Análises Clínicas e Toxicológicas, Laboratório de Imunologia de Células B, São Paulo, SP, Brasil
| | - Carlos Rodrigo Zárate-Bladés
- Universidade Federal de Santa Catarina, Departamento de Microbiologia, Imunologia e Parasitologia, Laboratório de Imunorregulação, Florianópolis, SC, Brasil
| | - Carla Claser
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Parasitologia, São Paulo, SP, Brasil
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10
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O'Connor JH, McNamara HA, Cai Y, Coupland LA, Gardiner EE, Parish CR, McMorran BJ, Ganusov VV, Cockburn IA. Interactions with Asialo-Glycoprotein Receptors and Platelets Are Dispensable for CD8 + T Cell Localization in the Murine Liver. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:2738-2748. [PMID: 35649630 PMCID: PMC9308657 DOI: 10.4049/jimmunol.2101037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
Liver-resident CD8+ T cells can play critical roles in the control of pathogens, including Plasmodium and hepatitis B virus. Paradoxically, it has also been proposed that the liver may act as the main place for the elimination of CD8+ T cells at the resolution of immune responses. We hypothesized that different adhesion processes may drive residence versus elimination of T cells in the liver. Specifically, we investigated whether the expression of asialo-glycoproteins (ASGPs) drives the localization and elimination of effector CD8+ T cells in the liver, while interactions with platelets facilitate liver residence and protective function. Using murine CD8+ T cells activated in vitro, or in vivo by immunization with Plasmodium berghei sporozoites, we found that, unexpectedly, inhibition of ASGP receptors did not inhibit the accumulation of effector cells in the liver, but instead prevented these cells from accumulating in the spleen. In addition, enforced expression of ASGP on effector CD8+ T cells using St3GalI-deficient cells lead to their loss from the spleen. We also found, using different mouse models of thrombocytopenia, that severe reduction in platelet concentration in circulation did not strongly influence the residence and protective function of CD8+ T cells in the liver. These data suggest that platelets play a marginal role in CD8+ T cell function in the liver. Furthermore, ASGP-expressing effector CD8+ T cells accumulate in the spleen, not the liver, prior to their destruction.
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Affiliation(s)
- James H O'Connor
- Division of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia
- Australian National University Medical School, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Hayley A McNamara
- Division of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Yeping Cai
- Division of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Lucy A Coupland
- Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia; and
| | - Elizabeth E Gardiner
- Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia; and
| | - Christopher R Parish
- Division of Genome Science and Cancer, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia; and
| | - Brendan J McMorran
- Division of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Vitaly V Ganusov
- Department of Microbiology, University of Tennessee, Knoxville, TN
| | - Ian A Cockburn
- Division of Immunology and Infectious Disease, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia;
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11
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Mitchell RA, Altszuler R, Gonzalez S, Johnson R, Frevert U, Nardin E. Innate Immune Responses and P. falciparum CS Repeat-Specific Neutralizing Antibodies Following Vaccination by Skin Scarification. Front Immunol 2022; 13:801111. [PMID: 35734173 PMCID: PMC9207416 DOI: 10.3389/fimmu.2022.801111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 05/09/2022] [Indexed: 11/17/2022] Open
Abstract
The skin is the site of host invasion by the mosquito-borne Plasmodium parasite, which caused an estimated 229 million infections and 409,000 deaths in 2019 according to WHO World Malaria report 2020. In our previous studies, we have shown that skin scarification (SS) with a P. falciparum circumsporozoite (CS) peptide in the oil-in-water adjuvant AddaVax containing a combination of TLR 7/8 and TLR 9 agonists can elicit sporozoite neutralizing antibodies. SS with AddaVax + TLR agonists, but not AddaVax alone, elicited CD4+ Th1 cells and IgG2a/c anti-repeat antibody. To explore the innate immune responses that may contribute to development of adaptive immunity following SS, we examined the skin at 4h and 24h post priming with CS peptide in AddaVax with or without TLR agonists. H&E stained and IHC-labeled dorsal skin sections obtained 24h post SS demonstrated a marked difference in the pattern of infiltration with F4/80+, CD11b+ and Ly6G+ cells at the immunization site, with the lowest intensity noted following SS with AddaVax + TLR agonists. Serum collected at 4h post SS, had reproducible increases in IL-6, MIP-3α, IL-22 and IP-10 (CXCL10) following SS with AddaVax + TLR agonists, but not with AddaVax alone. To begin to decipher the complex roles of these pro-inflammatory cytokines/chemokines, we utilized IP-10 deficient (IP-10 -/-) mice to examine the role of this chemokine in the development of anti-repeat antibody response following SS. In the absence of IP-10, the levels of Th1-type IgG2a/c antibody and kinetics of the primary anti-repeat antibody response were reduced following prime and boost. The IP-10 chemokine, present as early as 4h post prime, may provide an early serological marker for rapid screening of adjuvant formulations and delivery platforms to optimize SS-induced humoral immunity to CS repeats as well as other pathogens.
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12
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Disrupting a Plasmodium berghei putative phospholipase impairs efficient egress of merosomes. Int J Parasitol 2022; 52:547-558. [DOI: 10.1016/j.ijpara.2022.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/09/2022] [Accepted: 03/21/2022] [Indexed: 01/23/2023]
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13
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Temporão A, Sanches-Vaz M, Luís R, Nunes-Cabaço H, Smith TK, Prudêncio M, Figueiredo LM. Excreted Trypanosoma brucei proteins inhibit Plasmodium hepatic infection. PLoS Negl Trop Dis 2021; 15:e0009912. [PMID: 34714824 PMCID: PMC8580256 DOI: 10.1371/journal.pntd.0009912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 11/10/2021] [Accepted: 10/15/2021] [Indexed: 11/25/2022] Open
Abstract
Malaria, a disease caused by Plasmodium parasites, remains a major threat to public health globally. It is the most common disease in patients with sleeping sickness, another parasitic illness, caused by Trypanosoma brucei. We have previously shown that a T. brucei infection impairs a secondary P. berghei liver infection and decreases malaria severity in mice. However, whether this effect requires an active trypanosome infection remained unknown. Here, we show that Plasmodium liver infection can also be inhibited by the serum of a mouse previously infected by T. brucei and by total protein lysates of this kinetoplastid. Biochemical characterisation showed that the anti-Plasmodium activity of the total T. brucei lysates depends on its protein fraction, but is independent of the abundant variant surface glycoprotein. Finally, we found that the protein(s) responsible for the inhibition of Plasmodium infection is/are present within a fraction of ~350 proteins that are excreted to the bloodstream of the host. We conclude that the defence mechanism developed by trypanosomes against Plasmodium relies on protein excretion. This study opens the door to the identification of novel antiplasmodial intervention strategies.
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Affiliation(s)
- Adriana Temporão
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Margarida Sanches-Vaz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rafael Luís
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Helena Nunes-Cabaço
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Terry K. Smith
- Schools of Biology and Chemistry Biomedical Sciences Research Complex, The North Haugh, The University, St. Andrews, Scotland, United Kingdom
| | - Miguel Prudêncio
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Luisa M. Figueiredo
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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14
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Sharma PK, Kalia I, Kaushik V, Brünnert D, Quadiri A, Kashif M, Chahar KR, Agrawal A, Singh AP, Goyal P. STK35L1 regulates host cell cycle-related genes and is essential for Plasmodium infection during the liver stage of malaria. Exp Cell Res 2021; 406:112764. [PMID: 34358525 DOI: 10.1016/j.yexcr.2021.112764] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/30/2021] [Accepted: 07/31/2021] [Indexed: 11/28/2022]
Abstract
Protein kinases of both the parasite and the host are crucial in parasite invasion and survival and might act as drug targets against drug-resistant malaria. STK35L1 was among the top five hits in kinome-wide screening, suggesting its role in malaria's liver stage. However, the role of host STK35L1 in malaria remains elusive. In this study, we found that STK35L1 was highly upregulated during the infection of Plasmodium berghei (P. berghei) in HepG2 cells and mice liver, and knockdown of STK35L1 remarkably suppressed the sporozoites' infection in HepG2 cells. We showed that STAT3 is upregulated and phosphorylated during P. berghei sporozoites' infection, and STAT3 activation is required for both the upregulation of STK35L1 and STAT3. Furthermore, we found that ten cell cycle genes were upregulated in the sporozoite-infected hepatocytes. Knockdown of STK35L1 inhibited the basal expression of these genes except CDKN3 and GTSE1 in HepG2 cells. Thus, we identified STK35L1 as a host kinase that plays an obligatory role in malaria's liver stage and propose that it may serve as a potential drug target against drug-resistant malaria.
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Affiliation(s)
- Phulwanti Kumari Sharma
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Rajasthan, 305 817, India
| | - Inderjeet Kalia
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Vibha Kaushik
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Rajasthan, 305 817, India
| | - Daniela Brünnert
- Experimental Tumor Immunology, Department of Obstetrics and Gynecology, University of Würzburg Medical School, Würzburg, Germany
| | - Afshana Quadiri
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Mohammad Kashif
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Kirti Raj Chahar
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Rajasthan, 305 817, India
| | - Akhil Agrawal
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Rajasthan, 305 817, India
| | - Agam Prasad Singh
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
| | - Pankaj Goyal
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Rajasthan, 305 817, India.
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15
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Identification of a neutralizing epitope within minor repeat region of Plasmodium falciparum CS protein. NPJ Vaccines 2021; 6:10. [PMID: 33462218 PMCID: PMC7813878 DOI: 10.1038/s41541-020-00272-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 12/14/2020] [Indexed: 11/08/2022] Open
Abstract
Malaria remains a major cause of morbidity and mortality worldwide with 219 million infections and 435,000 deaths predominantly in Africa. The infective Plasmodium sporozoite is the target of a potent humoral immune response that can protect murine, simian and human hosts against challenge by malaria-infected mosquitoes. Early murine studies demonstrated that sporozoites or subunit vaccines based on the sporozoite major surface antigen, the circumsporozoite (CS) protein, elicit antibodies that primarily target the central repeat region of the CS protein. In the current murine studies, using monoclonal antibodies and polyclonal sera obtained following immunization with P. falciparum sporozoites or synthetic repeat peptides, we demonstrate differences in the ability of these antibodies to recognize the major and minor repeats contained in the central repeat region. The biological relevance of these differences in fine specificity was explored using a transgenic P. berghei rodent parasite expressing the P. falciparum CS repeat region. In these in vitro and in vivo studies, we demonstrate that the minor repeat region, comprised of three copies of alternating NANP and NVDP tetramer repeats, contains an epitope recognized by sporozoite-neutralizing antibodies. In contrast, murine monoclonal antibodies specific for the major CS repeats (NANP)n could be isolated from peptide-immunized mice that had limited or no sporozoite-neutralizing activity. These studies highlight the importance of assessing the fine specificity and functions of antirepeat antibodies elicited by P. falciparum CS-based vaccines and suggest that the design of immunogens to increase antibody responses to minor CS repeats may enhance vaccine efficacy.
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16
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Putrianti ED, Schmidt-Christensen A, Heussler V, Matuschewski K, Ingmundson A. A Plasmodium cysteine protease required for efficient transition from the liver infection stage. PLoS Pathog 2020; 16:e1008891. [PMID: 32956401 PMCID: PMC7529260 DOI: 10.1371/journal.ppat.1008891] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/01/2020] [Accepted: 08/15/2020] [Indexed: 01/23/2023] Open
Abstract
The transitions between developmental stages are critical points in the Plasmodium life cycle. The development of Plasmodium in the livers of their mammalian hosts bridges malaria transmission and the onset of clinical symptoms elicited by red blood cell infection. The egress of Plasmodium parasites from the liver must be a carefully orchestrated process to ensure a successful switch to the blood stage of infection. Cysteine protease activity is known to be required for liver-stage Plasmodium egress, but the crucial cysteine protease(s) remained unidentified. Here, we characterize a member of the papain-like cysteine protease family, Plasmodium berghei serine repeat antigen 4 (PbSERA4), that is required for efficient initiation of blood-stage infection. Through the generation PbSERA4-specific antisera and the creation of transgenic parasites expressing fluorescently tagged protein, we show that PbSERA4 is expressed and proteolytically processed in the liver and blood stages of infection. Targeted disruption of PbSERA4 results in viable and virulent blood-stage parasites. However, upon transmission from mosquitoes to mice, Pbsera4(-) parasites displayed a reduced capacity to initiate a new round of asexual blood-stage replication. Our results from cultured cells indicate that this defect results from an inability of the PbSERA4-deficient parasites to egress efficiently from infected cells at the culmination of liver-stage development. Protection against infection with wildtype P. berghei could be generated in animals in which Pbsera4(-) parasites failed to establish infection. Our findings confirm that liver-stage merozoite release is an active process and demonstrate that this parasite-encoded cysteine protease contributes to parasite escape from the liver. Plasmodium parasites cause over 200 million cases of malaria every year. When parasites are transmitted by mosquito bite, they initially colonize the liver before they move into the blood and cause disease. During successful transition from the liver into the blood, Plasmodium cloak themselves in host plasma membrane as they egress from the liver cells. Although some aspects of how Plasmodium exit their host hepatocytes appear unique, certain attributes are shared across diverse pathogens. For example, protease activity is required not only for multiple stages of Plasmodium exit, but is also involved in the egress of some bacteria and other protozoan. Here we characterize a protease in Plasmodium berghei that is expressed in the liver and conserved across Plasmodium species. Through gene targeting, we found PbSERA4 is required for efficient egress of Plasmodium from the liver. In the absence of this protease the transition between the liver and blood stages of growth is prolonged due to inefficient parasite release from liver cells. These findings provide new insights into the function of a conserved Plasmodium protease and into the process of Plasmodium escape from the liver.
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Affiliation(s)
- Elyzana Dewi Putrianti
- Parasitology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
- Metabolism of Microbial Pathogens, Robert Koch Institute, Berlin, Germany
| | - Anja Schmidt-Christensen
- Department of Experimental Medical Science, Lund University, Lund, Sweden
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Volker Heussler
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Kai Matuschewski
- Parasitology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
- Department of Molecular Parasitology, Institute of Biology, Humboldt University Berlin, Berlin, Germany
| | - Alyssa Ingmundson
- Parasitology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
- Department of Molecular Parasitology, Institute of Biology, Humboldt University Berlin, Berlin, Germany
- * E-mail:
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17
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Flores-Garcia Y, Herrera SM, Jhun H, Pérez-Ramos DW, King CR, Locke E, Raghunandan R, Zavala F. Optimization of an in vivo model to study immunity to Plasmodium falciparum pre-erythrocytic stages. Malar J 2019; 18:426. [PMID: 31849326 PMCID: PMC6918627 DOI: 10.1186/s12936-019-3055-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 12/07/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The circumsporozoite protein (CSP) of Plasmodium is a key surface antigen that induces antibodies and T-cells, conferring immune protection in animal models and humans. However, much of the work on CSP and immunity has been developed based on studies using rodent or non-human primate CSP antigens, which may not be entirely translatable to CSP expressed by human malaria parasites, especially considering the host specificity of the different species. METHODS Using a genetically engineered strain of Plasmodium berghei that expresses luciferase, GFP and the Plasmodium falciparum orthologue of CSP, the effect of laboratory preparation, mosquito treatment and mouse factors on sporozoite infectivity was assessed using an in vivo bioluminescence assay on mice. This assay was compared with a PCR-based protection assay using an already described monoclonal antibody that can provide sterile protection against sporozoite challenge. RESULTS Bioluminescence assay demonstrated similar detection levels of the quantity and kinetics of liver-stage infection, compared to PCR-based detection. This assay was used to evaluate treatment of sporozoite and delivery method on mouse infectivity, as well as the effects of age, sex and strain of mice. Finally, this assay was used to test the protective capacity of monoclonal antibody AB317; results strongly recapitulate the findings of previous work on this antibody. CONCLUSIONS The PbGFP-Luc line and in vivo bioluminescence imaging provide highly sensitive read-outs of liver-stage infection in mice, and this method can be useful to reliably evaluate potency of pre-erythrocytic interventions.
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Affiliation(s)
- Yevel Flores-Garcia
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Sonia M Herrera
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Hugo Jhun
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Daniel W Pérez-Ramos
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - C Richter King
- PATH Malaria Vaccine Initiative, 455 Massachusetts Avenue, NW, Suite 1000, Washington, DC, 20001, USA
| | - Emily Locke
- PATH Malaria Vaccine Initiative, 455 Massachusetts Avenue, NW, Suite 1000, Washington, DC, 20001, USA
| | - Ramadevi Raghunandan
- PATH Malaria Vaccine Initiative, 455 Massachusetts Avenue, NW, Suite 1000, Washington, DC, 20001, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA.
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18
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Gupta R, Mishra A, Choudhary HH, Narwal SK, Nayak B, Srivastava PN, Mishra S. Secreted protein with altered thrombospondin repeat (SPATR) is essential for asexual blood stages but not required for hepatocyte invasion by the malaria parasite Plasmodium berghei. Mol Microbiol 2019; 113:478-491. [PMID: 31755154 DOI: 10.1111/mmi.14432] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 11/30/2022]
Abstract
Upon entering its mammalian host, the malaria parasite productively invades two distinct cell types, that is, hepatocytes and erythrocytes during which several adhesins/invasins are thought to be involved. Many surface-located proteins containing thrombospondin Type I repeat (TSR) which help establish host-parasite molecular crosstalk have been shown to be essential for mammalian infection. Previous reports indicated that antibodies produced against Plasmodium falciparum secreted protein with altered thrombospondin repeat (SPATR) block hepatocyte invasion by sporozoites but no genetic evidence of its contribution to invasion has been reported. After failing to generate Spatr knockout in Plasmodium berghei blood stages, a conditional mutagenesis system was employed. Here, we show that SPATR plays an essential role during parasite's blood stages. Mutant salivary gland sporozoites exhibit normal motility, hepatocyte invasion, liver stage development and rupture of the parasitophorous vacuole membrane resulting in merosome formation. But these mutant hepatic merozoites failed to establish a blood stage infection in vivo. We provide direct evidence that SPATR is not required for hepatocyte invasion but plays an essential role during the blood stages of P. berghei.
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Affiliation(s)
- Roshni Gupta
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Akancha Mishra
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Hadi Hasan Choudhary
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Sunil Kumar Narwal
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Bandita Nayak
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Pratik Narain Srivastava
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Satish Mishra
- Division of Molecular Parasitology and Immunology, CSIR-Central Drug Research Institute, Lucknow, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
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19
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Sanches-Vaz M, Temporão A, Luis R, Nunes-Cabaço H, Mendes AM, Goellner S, Carvalho T, Figueiredo LM, Prudêncio M. Trypanosoma brucei infection protects mice against malaria. PLoS Pathog 2019; 15:e1008145. [PMID: 31703103 PMCID: PMC6867654 DOI: 10.1371/journal.ppat.1008145] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 11/20/2019] [Accepted: 10/11/2019] [Indexed: 12/22/2022] Open
Abstract
Sleeping sickness and malaria are parasitic diseases with overlapping geographical distributions in sub-Saharan Africa. We hypothesized that the immune response elicited by an infection with Trypanosoma brucei, the etiological agent of sleeping sickness, would inhibit a subsequent infection by Plasmodium, the malaria parasite, decreasing the severity of its associated pathology. To investigate this, we established a new co-infection model in which mice were initially infected with T. brucei, followed by administration of P. berghei sporozoites. We observed that a primary infection by T. brucei significantly attenuates a subsequent infection by the malaria parasite, protecting mice from experimental cerebral malaria and prolonging host survival. We further observed that an ongoing T. brucei infection leads to an accumulation of lymphocyte-derived IFN-γ in the liver, limiting the establishment of a subsequent hepatic infection by P. berghei sporozoites. Thus, we identified a novel host-mediated interaction between two parasitic infections, which may be epidemiologically relevant in regions of Trypanosoma/Plasmodium co-endemicity. Despite the geographical overlap between the parasites that cause sleeping sickness and malaria, the reciprocal impact of a co-infection by T. brucei and Plasmodium had hitherto not been assessed. We hypothesized that the strong immune response elicited by a T. brucei infection could potentially limit the ability of Plasmodium parasites to infect the same host. In this study, we showed that a primary infection by T. brucei significantly attenuates a subsequent infection by the malaria parasite. Importantly, a significant proportion of the co-infected mice do not develop Plasmodium parasitemia, and those few that do, do not display symptoms of severe malaria and survive longer than their singly infected counterparts. We further showed that the prevention or delay in appearance of malaria parasites in the blood results from a dramatic impairment of the preceding liver infection by Plasmodium, which is mediated by the strong immune response mounted against the primary T. brucei infection. Our study provides new insights for a novel inter-pathogen interaction that may bear great epidemiological significance in regions of Trypanosoma/Plasmodium co-endemicity.
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Affiliation(s)
- Margarida Sanches-Vaz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Adriana Temporão
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rafael Luis
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Helena Nunes-Cabaço
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - António M. Mendes
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Sarah Goellner
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Tânia Carvalho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Luisa M. Figueiredo
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- * E-mail: (LMF); (MP)
| | - Miguel Prudêncio
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- * E-mail: (LMF); (MP)
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20
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Sato Y, Ries S, Stenzel W, Fillatreau S, Matuschewski K. The Liver-Stage Plasmodium Infection Is a Critical Checkpoint for Development of Experimental Cerebral Malaria. Front Immunol 2019; 10:2554. [PMID: 31736970 PMCID: PMC6837997 DOI: 10.3389/fimmu.2019.02554] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 10/15/2019] [Indexed: 12/20/2022] Open
Abstract
Cerebral malaria is a life-threatening complication of malaria in humans, and the underlying pathogenic mechanisms are widely analyzed in a murine model of experimental cerebral malaria (ECM). Here, we show abrogation of ECM by hemocoel sporozoite-induced infection of a transgenic Plasmodium berghei line that overexpresses profilin, whereas these parasites remain fully virulent in transfusion-mediated blood infection. We, thus, demonstrate the importance of the clinically silent liver-stage infection for modulating the onset of ECM. Even though both parasites triggered comparable splenic immune cell expansion and accumulation of antigen-experienced CD8+ T cells in the brain, infection with transgenic sporozoites did not lead to cerebral vascular damages and suppressed the recruitment of overall lymphocyte populations. Strikingly, infection with the transgenic strain led to maintenance of CD115+Ly6C+ monocytes, which disappear in infected animals prone to ECM. An early induction of IL-10, IL-12p70, IL-6, and TNF at the time when parasites emerge from the liver might lead to a diminished induction of hepatic immunity. Collectively, our study reveals the essential role of early host interactions in the liver that may dampen the subsequent pro-inflammatory immune responses and influence the occurrence of ECM, highlighting a novel checkpoint in this fatal pathology.
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Affiliation(s)
- Yuko Sato
- Parasitology Unit, Max Planck Institute for Infection Biology, Berlin, Germany.,Department of Microbiology and Immunology, Keio University School of Medicine, Tokyo, Japan
| | - Stefanie Ries
- Immune Regulation Research Group, Deutsches Rheuma-Forschungszentrum, Berlin, Germany
| | - Werner Stenzel
- Department of Neuropathology, Charité - Universitätmedizin, Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin, Germany
| | - Simon Fillatreau
- Immune Regulation Research Group, Deutsches Rheuma-Forschungszentrum, Berlin, Germany.,Department of Immunology, Infectiology and Haematology (I2H), Institut Necker-Enfants Malades, INSERM U1151-CNRS UMR 8253, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,AP-HP, Hôpital Necker Enfants Malades, Paris, France
| | - Kai Matuschewski
- Parasitology Unit, Max Planck Institute for Infection Biology, Berlin, Germany.,Department of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, Germany
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21
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Antibody-Dependent, Gamma Interferon-Independent Sterilizing Immunity Induced by a Subunit Malaria Vaccine. Infect Immun 2019; 87:IAI.00236-19. [PMID: 31308085 DOI: 10.1128/iai.00236-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/03/2019] [Indexed: 12/21/2022] Open
Abstract
The development of effective malaria vaccines is hampered by incomplete understanding of the immunological correlates of protective immunity. Recently, the moderate clinical efficacy of the Plasmodium falciparum circumsporozoite protein (CSP)-based RTS,S/AS01E vaccine in phase 3 studies highlighted the urgency to design and test more efficacious next-generation malaria vaccines. In this study, we report that immunization with recombinant CSP from Plasmodium yoelii (rPyCSP), when delivered in Montanide ISA 51, induced sterilizing immunity against sporozoite challenge in C57BL/6 and BALB/c strains of mice. This immunity was antibody dependent, as evidenced by the complete loss of immunity in B-cell-knockout (KO) mice and by the ability of immune sera to neutralize sporozoite infectivity in mice. Th2-type isotype IgG1 antibody levels were associated with protective immunity. The fact that immunized gamma interferon (IFN-γ)-KO mice and wild-type (WT) mice have similar levels of protective immunity and the absence of IFN-γ-producing CD4+ and CD8+ T cells in protected mice, as shown by flow cytometry, indicate that the immunity is IFN-γ independent. Protection against sporozoite challenge correlated with higher frequencies of CD4+ T cells that express interleukin-2 (IL-2), IL-4, and tumor necrosis factor alpha (TNF-α). In the RTS,S study, clinical immunity was associated with higher IgG levels and frequencies of IL-2- and TNF-α-producing CD4+ T cells. The other hallmarks of immunity in our study included an increased number of follicular B cells but a loss in follicular T helper cells. These results provide an excellent model system to evaluate the efficacy of novel adjuvants and vaccine dosage and determine the correlates of immunity in the search for superior malaria vaccine candidates.
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22
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Development and evaluation of a loop-mediated isothermal amplification assay for rapid detection of Leishmania amazonensis in skin samples. Exp Parasitol 2019; 203:23-29. [DOI: 10.1016/j.exppara.2019.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 05/15/2019] [Accepted: 05/27/2019] [Indexed: 11/17/2022]
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23
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Vom Steeg LG, Flores-Garcia Y, Zavala F, Klein SL. Irradiated sporozoite vaccination induces sex-specific immune responses and protection against malaria in mice. Vaccine 2019; 37:4468-4476. [PMID: 31262583 PMCID: PMC7862922 DOI: 10.1016/j.vaccine.2019.06.075] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/23/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
In both preclinical animal studies and human clinical trials, adult females tend to develop greater adaptive immune responses than males following receipt of either viral or bacterial vaccines. While there is currently no approved malaria vaccine, several anti-sporozoite vaccines, including RTS,S/AS01 and attenuated sporozoite vaccines, are in development, but the impact of sex and age on their efficacy remains undefined. To examine sex differences in the efficacy of anti-sporozoite stage malaria vaccination, adult (10 weeks of age) or juvenile (11 days of age) male and female C3H mice were twice vaccinated with irradiated transgenic Plasmodium berghei sporozoites expressing the P. falciparum circumsporozoite (CSP) protein and 45 days post boost vaccination, mice were challenged with transgenic P. berghei via mosquito bite or intradermal challenge. Immunization with irradiated sporozoites resulted in greater protection against challenge in adult females, which was associated with greater anti-CSP antibody production and avidity, as well as greater hepatic, but not splenic, CD8+ T cell IFNƴ production in adult females than adult males. No sex differences in adaptive immune responses or protection were observed in mice vaccinated prior to puberty, suggesting a role for sex steroid hormones. Depletion of testosterone in males increased, whereas rescue of testosterone decreased, anti-CSP antibody production, the number of antigen-specific CD8+ T cells isolated from the liver, and protection following parasite challenge. Conversely, depletion of sex steroids in female mice did not alter vaccine-induced responses or protection following challenge. These data suggest that elevated testosterone concentrations in males reduce adaptive immunity and contribute to sex differences in malaria vaccine efficacy.
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Affiliation(s)
- Landon G Vom Steeg
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, MD, USA
| | - Yevel Flores-Garcia
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, MD, USA
| | - Fidel Zavala
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, MD, USA
| | - Sabra L Klein
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, MD, USA; Department of Biochemistry and Molecular Biology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
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24
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Goh YS, McGuire D, Rénia L. Vaccination With Sporozoites: Models and Correlates of Protection. Front Immunol 2019; 10:1227. [PMID: 31231377 PMCID: PMC6560154 DOI: 10.3389/fimmu.2019.01227] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 05/14/2019] [Indexed: 12/14/2022] Open
Abstract
Despite continuous efforts, the century-old goal of eradicating malaria still remains. Multiple control interventions need to be in place simultaneously to achieve this goal. In addition to effective control measures, drug therapies and insecticides, vaccines are critical to reduce mortality and morbidity. Hence, there are numerous studies investigating various malaria vaccine candidates. Most of the malaria vaccine candidates are subunit vaccines. However, they have shown limited efficacy in Phase II and III studies. To date, only whole parasite formulations have been shown to induce sterile immunity in human. In this article, we review and discuss the recent developments in vaccination with sporozoites and the mechanisms of protection involved.
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Affiliation(s)
- Yun Shan Goh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore
| | - Daniel McGuire
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Laurent Rénia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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25
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Choudhary HH, Gupta R, Mishra S. PKAc is not required for the preerythrocytic stages of Plasmodium berghei. Life Sci Alliance 2019; 2:2/3/e201900352. [PMID: 31142638 PMCID: PMC6545604 DOI: 10.26508/lsa.201900352] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/22/2019] [Accepted: 05/22/2019] [Indexed: 12/12/2022] Open
Abstract
The mutant salivary gland sporozoites lacking PKAc are able to glide, invade hepatocytes, and mature into hepatic merozoites, which release successfully from the merosome, however, fail to initiate blood stage infection when inoculated into mice. Plasmodium sporozoites invade hepatocytes to initiate infection in the mammalian host. In the infected hepatocytes, sporozoites undergo rapid expansion and differentiation, resulting in the formation and release of thousands of invasive merozoites into the bloodstream. Both sporozoites and merozoites invade their host cells by activation of a signaling cascade followed by discharge of micronemal content. cAMP-dependent protein kinase catalytic subunit (PKAc)–mediated signaling plays an important role in merozoite invasion of erythrocytes, but its role during other stages of the parasite remains unknown. Becaused of the essentiality of PKAc in blood stages, we generated conditional mutants of PKAc by disrupting the gene in Plasmodium berghei sporozoites. The mutant salivary gland sporozoites were able to glide, invaded hepatocytes, and matured into hepatic merozoites which were released successfully from merosome, however failed to initiate blood stage infection when inoculated into mice. Our results demonstrate that malaria parasite complete preerythrocytic stages development without PKAc, raising the possibility that the PKAc independent signaling operates in preerythrocytic stages of P. berghei.
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Affiliation(s)
| | - Roshni Gupta
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India
| | - Satish Mishra
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow, India .,Academy of Scientific and Innovative Research, Ghaziabad, India
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26
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Kurup SP, Anthony SM, Hancox LS, Vijay R, Pewe LL, Moioffer SJ, Sompallae R, Janse CJ, Khan SM, Harty JT. Monocyte-Derived CD11c + Cells Acquire Plasmodium from Hepatocytes to Prime CD8 T Cell Immunity to Liver-Stage Malaria. Cell Host Microbe 2019; 25:565-577.e6. [PMID: 30905437 DOI: 10.1016/j.chom.2019.02.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/04/2018] [Accepted: 02/07/2019] [Indexed: 01/16/2023]
Abstract
Plasmodium sporozoites inoculated by mosquitoes migrate to the liver and infect hepatocytes prior to release of merozoites that initiate symptomatic blood-stage malaria. Plasmodium parasites are thought to be restricted to hepatocytes throughout this obligate liver stage of development, and how liver-stage-expressed antigens prime productive CD8 T cell responses remains unknown. We found that a subset of liver-infiltrating monocyte-derived CD11c+ cells co-expressing F4/80, CD103, CD207, and CSF1R acquired parasites during the liver stage of malaria, but only after initial hepatocyte infection. These CD11c+ cells found in the infected liver and liver-draining lymph nodes exhibited transcriptionally and phenotypically enhanced antigen-presentation functions and primed protective CD8 T cell responses against Plasmodium liver-stage-restricted antigens. Our findings highlight a previously unrecognized aspect of Plasmodium biology and uncover the fundamental mechanism by which CD8 T cell responses are primed against liver-stage malaria antigens.
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Affiliation(s)
- Samarchith P Kurup
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Scott M Anthony
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Lisa S Hancox
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Rahul Vijay
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Lecia L Pewe
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Steven J Moioffer
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA
| | - Ramakrishna Sompallae
- Department of Pathology, University of Iowa, Iowa City, IA 52242, USA; Iowa Institute of Human Genetics, University of Iowa, Iowa City, IA 52242, USA
| | - Chris J Janse
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center (LUMC), 2333ZA Leiden, the Netherlands
| | - Shahid M Khan
- Leiden Malaria Research Group, Department of Parasitology, Leiden University Medical Center (LUMC), 2333ZA Leiden, the Netherlands
| | - John T Harty
- Department of Microbiology and Immunology, University of Iowa, Iowa City, IA 52242, USA; Department of Pathology, University of Iowa, Iowa City, IA 52242, USA; Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, USA.
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27
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Abstract
Plasmodium sporozoites are injected into the skin as mosquitoes probe for blood. From here, they migrate through the dermis to find blood vessels which they enter in order to be rapidly carried to the liver, where they invade hepatocytes and develop into the next life cycle stage, the exoerythrocytic stage. Once sporozoites enter the blood circulation, they are found in hepatocytes within minutes. In contrast, sporozoite exit from the inoculation site resembles a slow trickle and occurs over several hours. Thus, sporozoites spend the majority of their extracellular time at the inoculation site, raising the hypothesis that this is when the malarial parasite is most vulnerable to antibody-mediated destruction. Here, we investigate this hypothesis and demonstrate that the neutralizing capacity of circulating antibodies is greater at the inoculation site than in the blood circulation. Furthermore, these antibodies are working, at least in part, by impacting sporozoite motility at the inoculation site. Using actively and passively immunized mice, we found that most parasites are either immobilized at the site of injection or display reduced motility, particularly in their net displacement. We also found that antibodies severely impair the entry of sporozoites into the bloodstream. Overall, our data suggest that antibodies targeting the migratory sporozoite exert a large proportion of their protective effect at the inoculation site.IMPORTANCE Studies in experimental animal models and humans have shown that antibodies against Plasmodium sporozoites abolish parasite infectivity and provide sterile immunity. While it is well documented that these antibodies can be induced after immunization with attenuated parasites or subunit vaccines, the mechanisms by and location in which they neutralize parasites have not been fully elucidated. Here, we report studies indicating that these antibodies display a significant portion of their protective effect in the skin after injection of sporozoites and that one mechanism by which they work is by impairing sporozoite motility, thus diminishing their ability to reach blood vessels. These results suggest that immune protection against malaria begins at the earliest stages of parasite infection and emphasize the need of performing parasite challenge in the skin for the evaluation of protective immunity.
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28
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Ishino T, Murata E, Tokunaga N, Baba M, Tachibana M, Thongkukiatkul A, Tsuboi T, Torii M. Rhoptry neck protein 2 expressed in Plasmodium sporozoites plays a crucial role during invasion of mosquito salivary glands. Cell Microbiol 2018; 21:e12964. [PMID: 30307699 PMCID: PMC6587811 DOI: 10.1111/cmi.12964] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/28/2018] [Accepted: 10/05/2018] [Indexed: 01/03/2023]
Abstract
Malaria parasite transmission to humans is initiated by the inoculation of Plasmodium sporozoites into the skin by mosquitoes. Sporozoites develop within mosquito midgut oocysts, first invade the salivary glands of mosquitoes, and finally infect hepatocytes in mammals. The apical structure of sporozoites is conserved with the infective forms of other apicomplexan parasites that have secretory organelles, such as rhoptries and micronemes. Because some rhoptry proteins are crucial for Plasmodium merozoite infection of erythrocytes, we examined the roles of rhoptry proteins in sporozoites. Here, we demonstrate that rhoptry neck protein 2 (RON2) is also localized to rhoptries in sporozoites. To elucidate RON2 function in sporozoites, we applied a promoter swapping strategy to restrict ron2 transcription to the intraerythrocytic stage in the rodent malaria parasite, Plasmodium berghei. Ron2 knockdown sporozoites were severely impaired in their ability to invade salivary glands, via decreasing the attachment capacity to the substrate. This is the first rhoptry protein demonstrated to be involved in salivary gland invasion. In addition, ron2 knockdown sporozoites showed less infectivity to hepatocytes, possibly due to decreased attachment/gliding ability, indicating that parts of the parasite invasion machinery are conserved, but their contribution might differ among infective forms. Our sporozoite stage‐specific knockdown system will help to facilitate understanding the comprehensive molecular mechanisms of parasite invasion of target cells.
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Affiliation(s)
- Tomoko Ishino
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Eri Murata
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan.,Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Naohito Tokunaga
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Minami Baba
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | - Mayumi Tachibana
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
| | | | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Motomi Torii
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Japan
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29
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A human monoclonal antibody prevents malaria infection by targeting a new site of vulnerability on the parasite. Nat Med 2018; 24:408-416. [PMID: 29554083 PMCID: PMC5893371 DOI: 10.1038/nm.4512] [Citation(s) in RCA: 189] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 01/26/2018] [Indexed: 01/07/2023]
Abstract
Development of a highly effective vaccine or antibodies for the prevention and ultimately elimination of malaria is urgently needed. Here we report the isolation of a number of human monoclonal antibodies directed against the Plasmodium falciparum (Pf) circumsporozoite protein (PfCSP) from several subjects immunized with an attenuated Pf whole-sporozoite (SPZ) vaccine (Sanaria PfSPZ Vaccine). Passive transfer of one of these antibodies, monoclonal antibody CIS43, conferred high-level, sterile protection in two different mouse models of malaria infection. The affinity and stoichiometry of CIS43 binding to PfCSP indicate that there are two sequential multivalent binding events encompassing the repeat domain. The first binding event is to a unique 'junctional' epitope positioned between the N terminus and the central repeat domain of PfCSP. Moreover, CIS43 prevented proteolytic cleavage of PfCSP on PfSPZ. Analysis of crystal structures of the CIS43 antigen-binding fragment in complex with the junctional epitope determined the molecular interactions of binding, revealed the epitope's conformational flexibility and defined Asn-Pro-Asn (NPN) as the structural repeat motif. The demonstration that CIS43 is highly effective for passive prevention of malaria has potential application for use in travelers, military personnel and elimination campaigns and identifies a new and conserved site of vulnerability on PfCSP for next-generation rational vaccine design.
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30
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Structural basis for antibody recognition of the NANP repeats in Plasmodium falciparum circumsporozoite protein. Proc Natl Acad Sci U S A 2017; 114:E10438-E10445. [PMID: 29138320 PMCID: PMC5715787 DOI: 10.1073/pnas.1715812114] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The Plasmodium falciparum circumsporozoite protein (CSP) has been studied for decades as a potential immunogen, but little structural information is available on how antibodies recognize the immunodominant NANP repeats within CSP. The most advanced vaccine candidate is RTS,S, which includes multiple NANP repeats. Here, we analyzed two functional antibodies from an RTS,S trial and determined the number of repeats that interact with the antibody Fab fragments using isothermal titration calorimetry and X-ray crystallography. Using negative-stain electron microscopy, we also established how the antibody binds to the NANP repeat region in a recombinant CSP construct. The structural features outlined here provide a rationale for structure-based immunogen design to improve upon the efficacy of the current RTS,S vaccine. Acquired resistance against antimalarial drugs has further increased the need for an effective malaria vaccine. The current leading candidate, RTS,S, is a recombinant circumsporozoite protein (CSP)-based vaccine against Plasmodium falciparum that contains 19 NANP repeats followed by a thrombospondin repeat domain. Although RTS,S has undergone extensive clinical testing and has progressed through phase III clinical trials, continued efforts are underway to enhance its efficacy and duration of protection. Here, we determined that two monoclonal antibodies (mAbs 311 and 317), isolated from a recent controlled human malaria infection trial exploring a delayed fractional dose, inhibit parasite development in vivo by at least 97%. Crystal structures of antibody fragments (Fabs) 311 and 317 with an (NPNA)3 peptide illustrate their different binding modes. Notwithstanding, one and three of the three NPNA repeats adopt similar well-defined type I β-turns with Fab311 and Fab317, respectively. Furthermore, to explore antibody binding in the context of P. falciparum CSP, we used negative-stain electron microscopy on a recombinant shortened CSP (rsCSP) construct saturated with Fabs. Both complexes display a compact rsCSP with multiple Fabs bound, with the rsCSP–Fab311 complex forming a highly organized helical structure. Together, these structural insights may aid in the design of a next-generation malaria vaccine.
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31
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Faria AR, Pires SDF, Reis AB, Coura-Vital W, Silveira JAGD, Sousa GMD, Bueno MLC, Gazzinelli RT, Andrade HMD. Canine visceral leishmaniasis follow-up: a new anti-IgG serological test more sensitive than ITS-1 conventional PCR. Vet Parasitol 2017; 248:62-67. [PMID: 29173543 DOI: 10.1016/j.vetpar.2017.10.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 11/17/2022]
Abstract
Visceral leishmaniasis (VL) is a neglected tropical disease with dogs serving as reservoirs for one of its etiological agents, Leishmania infantum. In Brazil, VL control involves culling of seropositive dogs, among other actions. However, the most employed serological tests lack accuracy, and are not able to detect canine visceral leishmaniasis (CVL) during the early stages of infection. Early detection of CVL is highly desirable in order to shorten the contact time between the infected reservoirs and the vectors. In this study, we investigated the ability of two multiepitope proteins, PQ10 and PQ20, to detect CVL at earlier stages than currently employed methods, including ITS-1 conventional PCR. Using serum samples from naturally infected dogs, we observed that ELISA-PQ10 and ELISA-PQ20 were able to detect Leishmania infection at earlier time points as compared with kDNA PCR-RFLP in anti-IgG and anti-IgM assays. Using sera from experimentally infected dogs, we monitored seroconversion using multiepitope proteins, ELISA-crude antigen, as well as ITS-1 conventional and real-time PCR. While seroconversion was detected by ELISA-crude antigen in 16.6% of the dogs, multiepitope proteins were able to detect seroconversion in more than 80% of them. Moreover, the ability of ELISA-PQ10 and ELISA-PQ20 to detect Leishmania infection at earlier time points as compared with conventional PCR was also confirmed in experimental infection dogs' sera. Immunofluorescence to Babesia canis and Ehrlichia canis did not show cross-reactions with ELISA-PQ10/PQ20 positive samples. Results of real-time PCR and ELISA with multiepitope proteins were very similar, with concordances between 80 and 100%. Furthermore, our findings indicated that PQ10 and PQ20 immunoassays can be related to parasite load. ELISA-PQ10 and ELISA-PQ20 are more sensitive diagnostic tools for early CVL detection as compared with other methods They could potentially be used in screening tests due to easy execution and low costs facilities.
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Affiliation(s)
- Angélica Rosa Faria
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil.
| | - Simone da Fonseca Pires
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil
| | - Alexandre Barbosa Reis
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, CEP 35400-000, Ouro Preto, MG, Brazil
| | - Wendel Coura-Vital
- Núcleo de Pesquisa em Ciências Biológicas, Universidade Federal de Ouro Preto, CEP 35400-000, Ouro Preto, MG, Brazil
| | - Júlia Angélica Gonçalves da Silveira
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil
| | - Gabriela Matos de Sousa
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil
| | - Melissa Luíza Couto Bueno
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil
| | - Ricardo Tostes Gazzinelli
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil; Centro de Pesquisas René Rachou - Fundação Oswaldo Cruz, CEP 30190-002, Belo Horizonte, MG, Brazil; Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, 01605, Worcester, MA, USA
| | - Hélida Monteiro de Andrade
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CEP 31270-910, Belo Horizonte, MG, Brazil
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Sack BK, Mikolajczak SA, Fishbaugher M, Vaughan AM, Flannery EL, Nguyen T, Betz W, Jane Navarro M, Foquet L, Steel RWJ, Billman ZP, Murphy SC, Hoffman SL, Chakravarty S, Sim BKL, Behet M, Reuling IJ, Walk J, Scholzen A, Sauerwein RW, Ishizuka AS, Flynn B, Seder RA, Kappe SHI. Humoral protection against mosquito bite-transmitted Plasmodium falciparum infection in humanized mice. NPJ Vaccines 2017; 2:27. [PMID: 29263882 PMCID: PMC5634440 DOI: 10.1038/s41541-017-0028-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 07/25/2017] [Accepted: 09/07/2017] [Indexed: 01/05/2023] Open
Abstract
A malaria vaccine that prevents infection will be an important new tool in continued efforts of malaria elimination, and such vaccines are under intense development for the major human malaria parasite Plasmodium falciparum (Pf). Antibodies elicited by vaccines can block the initial phases of parasite infection when sporozoites are deposited into the skin by mosquito bite and then target the liver for further development. However, there are currently no standardized in vivo preclinical models that can measure the inhibitory activity of antibody specificities against Pf sporozoite infection via mosquito bite. Here, we use human liver-chimeric mice as a challenge model to assess prevention of natural Pf sporozoite infection by antibodies. We demonstrate that these mice are consistently infected with Pf by mosquito bite and that this challenge can be combined with passive transfer of either monoclonal antibodies or polyclonal human IgG from immune serum to measure antibody-mediated blocking of parasite infection using bioluminescent imaging. This methodology is useful to down-select functional antibodies and to investigate mechanisms or immune correlates of protection in clinical trials, thereby informing rational vaccine optimization.
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Affiliation(s)
| | | | | | | | | | - Thao Nguyen
- Center for Infectious Disease Research, Seattle, WA USA
| | - Will Betz
- Center for Infectious Disease Research, Seattle, WA USA
| | | | - Lander Foquet
- Center for Infectious Disease Research, Seattle, WA USA
| | | | - Zachary P. Billman
- Departments of Laboratory Medicine and Microbiology and the Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA USA
| | - Sean C. Murphy
- Center for Infectious Disease Research, Seattle, WA USA
- Departments of Laboratory Medicine and Microbiology and the Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA USA
| | | | | | | | | | | | - Jona Walk
- Radboud University, Nijmegen, The Netherlands
| | | | | | | | | | | | - Stefan H. I. Kappe
- Center for Infectious Disease Research, Seattle, WA USA
- Department of Global Health, University of Washington, Seattle, WA USA
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Hopp CS, Bennett BL, Mishra S, Lehmann C, Hanson KK, Lin JW, Rousseau K, Carvalho FA, van der Linden WA, Santos NC, Bogyo M, Khan SM, Heussler V, Sinnis P. Deletion of the rodent malaria ortholog for falcipain-1 highlights differences between hepatic and blood stage merozoites. PLoS Pathog 2017; 13:e1006586. [PMID: 28922424 PMCID: PMC5602738 DOI: 10.1371/journal.ppat.1006586] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 08/16/2017] [Indexed: 01/10/2023] Open
Abstract
Proteases have been implicated in a variety of developmental processes during the malaria parasite lifecycle. In particular, invasion and egress of the parasite from the infected hepatocyte and erythrocyte, critically depend on protease activity. Although falcipain-1 was the first cysteine protease to be characterized in P. falciparum, its role in the lifecycle of the parasite has been the subject of some controversy. While an inhibitor of falcipain-1 blocked erythrocyte invasion by merozoites, two independent studies showed that falcipain-1 disruption did not affect growth of blood stage parasites. To shed light on the role of this protease over the entire Plasmodium lifecycle, we disrupted berghepain-1, its ortholog in the rodent parasite P. berghei. We found that this mutant parasite displays a pronounced delay in blood stage infection after inoculation of sporozoites. Experiments designed to pinpoint the defect of berghepain-1 knockout parasites found that it was not due to alterations in gliding motility, hepatocyte invasion or liver stage development and that injection of berghepain-1 knockout merosomes replicated the phenotype of delayed blood stage growth after sporozoite inoculation. We identified an additional role for berghepain-1 in preparing blood stage merozoites for infection of erythrocytes and observed that berghepain-1 knockout parasites exhibit a reticulocyte restriction, suggesting that berghepain-1 activity broadens the erythrocyte repertoire of the parasite. The lack of berghepain-1 expression resulted in a greater reduction in erythrocyte infectivity in hepatocyte-derived merozoites than it did in erythrocyte-derived merozoites. These observations indicate a role for berghepain-1 in processing ligands important for merozoite infectivity and provide evidence supporting the notion that hepatic and erythrocytic merozoites, though structurally similar, are not identical. Malaria affects hundreds of millions of people and is the cause of hundreds of thousands of deaths each year. Infection begins with the inoculation of sporozoites into the skin during the bite of an infected mosquito. Sporozoites subsequently travel to the liver, where they invade and replicate in hepatocytes, eventually releasing the stage of the parasite that is infectious for red blood cells, termed merozoites. Hepatic merozoites initiate blood stage infection, the stage that is responsible for the clinical symptoms of malaria. The blood stage of the parasite grows through repeated rounds of invasion, development and egress of blood stage merozoites, which then continue the cycle. Proteases are among the enzymes that are essential for parasite survival and their functions range from invasion of red blood cells, to the breakdown of red cell hemoglobin, to the release of parasites from red cells. As the function of the cysteine protease falcipain-1 in the lifecycle of the human malaria parasite Plasmodium falciparum remains poorly understood, we decided to study berghepain-1, the orthologue of the rodent malaria parasite P. berghei by generating a berghepain-1 deletion parasite. Using this mutant, we demonstrate that berghepain-1 has a critical role in both hepatic and erythrocytic merozoite infectivity. Little is known about differences between these two types of merozoites and our data leads us to conclude that these merozoites are not identical.
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Affiliation(s)
- Christine S. Hopp
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail: (CSH); (BLB); (PS)
| | - Brandy L. Bennett
- Department of Microbiology, New York University School of Medicine, New York, New York, United States of America
- * E-mail: (CSH); (BLB); (PS)
| | - Satish Mishra
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | | | - Kirsten K. Hanson
- Instituto de Medicina Molecular, Faculdade de Medicina Universidade de Lisboa, Lisbon, Portugal
| | - Jing-wen Lin
- Department of Parasitology, Leiden Malaria Research Group, Leiden University Medical Center, Leiden ZA, The Netherlands
| | - Kimberly Rousseau
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Filomena A. Carvalho
- Instituto de Medicina Molecular, Faculdade de Medicina Universidade de Lisboa, Lisbon, Portugal
| | - Wouter A. van der Linden
- Departments of Pathology and Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Nuno C. Santos
- Instituto de Medicina Molecular, Faculdade de Medicina Universidade de Lisboa, Lisbon, Portugal
| | - Matthew Bogyo
- Departments of Pathology and Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Shahid M. Khan
- Department of Parasitology, Leiden Malaria Research Group, Leiden University Medical Center, Leiden ZA, The Netherlands
| | - Volker Heussler
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - Photini Sinnis
- Department of Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Department of Microbiology, New York University School of Medicine, New York, New York, United States of America
- * E-mail: (CSH); (BLB); (PS)
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Monoclonal Antibodies against Plasmodium falciparum Circumsporozoite Protein. Antibodies (Basel) 2017; 6:antib6030011. [PMID: 31548526 PMCID: PMC6698827 DOI: 10.3390/antib6030011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/14/2017] [Accepted: 08/01/2017] [Indexed: 11/17/2022] Open
Abstract
Malaria is a mosquito-borne infectious disease caused by the parasite Plasmodium spp. Malaria continues to have a devastating impact on human health. Sporozoites are the infective forms of the parasite inside mosquito salivary glands. Circumsporozoite protein (CSP) is a major and immunodominant protective antigen on the surface of Plasmodium sporozoites. Here, we report a generation of specific monoclonal antibodies that recognize the central repeat and C-terminal regions of P. falciparum CSP. The monoclonal antibodies 3C1, 3C2, and 3D3-specific for the central repeat region-have higher titers and protective efficacies against challenge with sporozoites compared with 2A10, a gold standard monoclonal antibody that was generated in early 1980s.
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Development of a Novel Virus-Like Particle Vaccine Platform That Mimics the Immature Form of Alphavirus. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00090-17. [PMID: 28515133 PMCID: PMC5498722 DOI: 10.1128/cvi.00090-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 05/04/2017] [Indexed: 12/27/2022]
Abstract
Virus-like particles (VLPs) are noninfectious multiprotein structures that are engineered to self-assemble from viral structural proteins. Here, we developed a novel VLP-based vaccine platform utilizing VLPs from the chikungunya virus. We identified two regions within the envelope protein, a structural component of chikungunya, where foreign antigens can be inserted without compromising VLP structure. Our VLP displays 480 copious copies of an inserted antigen on the VLP surface in a highly symmetric manner and is thus capable of inducing strong immune responses against any inserted antigen. Furthermore, by mimicking the structure of the immature form of the virus, we altered our VLP's in vivo dynamics and enhanced its immunogenicity. We used the circumsporozoite protein (CSP) of the Plasmodium falciparum malaria parasite as an antigen and demonstrated that our VLP-based vaccine elicits strong immune responses against CSP in animals. The sera from immunized monkeys protected mice from malaria infection. Likewise, mice vaccinated with P. yoelii CSP-containing VLPs were protected from an infectious sporozoite challenge. Hence, our uniquely engineered VLP platform can serve as a blueprint for the development of vaccines against other pathogens and diseases.
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36
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Experimental mixed infection of Leishmania (Leishmania) amazonensis and Leishmania (L.) infantum in hamsters (Mesocricetus auratus). Parasitology 2017; 144:1191-1202. [PMID: 28487000 DOI: 10.1017/s0031182017000464] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In South America, visceral leishmaniasis is frequently caused by Leishmania infantum and, at an unknown frequency, by Leishmania amazonensis. Therefore, mixed infections with these organisms are possible. Mixed infections might affect the clinical course, immune response, diagnosis, treatment and epidemiology of the disease. Here we describe the clinical course of mixed infections with L. amazonensis and L. infantum in a hamster model. We show that mixed infections are associated with more severe clinical disease than infection with L. amazonensis or L. infantum alone. In spleens with mixed infections, L. infantum outcompeted L. amazonensis in the tissue, but not in culture from tissue. We found increased levels of IgG in animals infected with L. infantum. Although more than 30 bands were revealed in a Western blot, the highest immunogenicity was observed with proteins having molecular masses of 95 and 90 kDa, whereas proteins with molecular masses of lower than 50 kDa were reactive frequently with serum from hamsters infected with L. amazonensis, and proteins with molecular masses of 80 and 70 kDa were reactive only with serum from hamsters infected with L. infantum. This finding has important implications regarding the biology of Leishmania and humoral immune responses to infections with these organisms.
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A Prime/Boost PfCS14K M/MVA-sPfCS M Vaccination Protocol Generates Robust CD8 + T Cell and Antibody Responses to Plasmodium falciparum Circumsporozoite Protein and Protects Mice against Malaria. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00494-16. [PMID: 28298290 DOI: 10.1128/cvi.00494-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 03/07/2017] [Indexed: 11/20/2022]
Abstract
Vaccines against the preerythrocytic stages of malaria are appealing because the parasite can be eliminated before disease onset and because they offer the unique possibility of targeting the parasite with both antibodies and T cells. Although the role of CD8+ T cells in preerythrocytic malaria stages is well documented, a highly effective T cell-inducing vaccine remains to be advanced. Here we report the development of a prime-boost immunization regimen with the Plasmodium falciparum circumsporozoite protein (PfCS) fused to the oligomer-forming vaccinia virus A27 protein and a modified vaccinia virus Ankara (MVA) vector expressing PfCS. This protocol induced polyfunctional CD8+ T cells with an effector memory phenotype and high PfCS antibody levels. These immune responses correlated with inhibition of liver-stage parasitemia in 80% and sterile protection in 40% of mice challenged with a transgenic P. berghei parasite line that expressed PfCS. Our findings underscore the potential of T and B cell immunization strategies for improving protective effectiveness against malaria.
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38
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Espinosa DA, Christensen D, Muñoz C, Singh S, Locke E, Andersen P, Zavala F. Robust antibody and CD8 + T-cell responses induced by P. falciparum CSP adsorbed to cationic liposomal adjuvant CAF09 confer sterilizing immunity against experimental rodent malaria infection. NPJ Vaccines 2017; 2. [PMID: 28936360 PMCID: PMC5603302 DOI: 10.1038/s41541-017-0011-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite several decades of extensive research, the development of a highly efficacious malaria vaccine has yet to be accomplished. While the RTS,S malaria vaccine candidate shows the potential to prevent a substantial number of clinical malaria cases, significant improvements in protective efficacy are still needed. Multiple studies have shown that RTS,S induces protective antibody and CD4+ T-cell responses, but limited or negligible CD8+ T cells. In this study, we evaluated the immunogenicity and protective capacity of full-length recombinant Plasmodium falciparum circumsporozoite protein administered with the novel cationic liposomal adjuvant system CAF09. Using newly developed transgenic rodent malaria parasites expressing the full-length Plasmodium falciparum circumsporozoite protein, we demonstrate that this liposome-based protein-in-adjuvant formulation is capable of inducing robust antibody and CD8+ T-cell responses that strongly inhibit parasite infection and development of liver stages, conferring durable sterilizing immunity. These findings underscore the potential of liposome-based adjuvants for inducing robust humoral and CD8+ T-cell responses and warrant further studies toward the development of novel subunit vaccine formulations with this adjuvant system. A vaccine consisting of parasitic proteins enveloped by fatty molecules provides comprehensive protection against malaria in a rodent model, Previous and current malaria vaccines concentrate on priming antibodies to recognize malarial infection, despite evidence that, by activating ‘killer’ CD8+ T cells, greater protection is conferred against the disease. Fidel Zavala, of the Johns Hopkins University, United States, and an international group of researchers developed their vaccine by encapsulating proteins from the malaria-causing parasite Plasmodium falciparum in fat-based carriers called liposomes. In past experiments, killer T cells recruited via this vaccine-type have effectively protected against other diseases. In this study, the vaccine induced both CD8+ T cell and antibody responses and provided significant immunity against P. falciparum-instigated malaria. As a highly efficacious vaccine against malaria is not yet available, this research will likely prove invaluable in guiding further studies.
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Affiliation(s)
- Diego A Espinosa
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | - Dennis Christensen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Christian Muñoz
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Emily Locke
- PATH Malaria Vaccine Initiative, Washington DC, USA
| | - Peter Andersen
- Department of Infectious Disease Immunology, Statens Serum Institut, Copenhagen, Denmark
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA
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39
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Aguiar ACC, Figueiredo FJB, Neuenfeldt PD, Katsuragawa TH, Drawanz BB, Cunico W, Sinnis P, Zavala F, Krettli AU. Primaquine-thiazolidinones block malaria transmission and development of the liver exoerythrocytic forms. Malar J 2017; 16:110. [PMID: 28279180 PMCID: PMC5345155 DOI: 10.1186/s12936-017-1755-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/26/2017] [Indexed: 02/06/2023] Open
Abstract
Background Primaquine is an anti-malarial used to prevent Plasmodium vivax relapses and malaria transmission. However, PQ metabolites cause haemolysis in patients deficient in the enzyme glucose-6-phosphate dehydrogenase (G6PD). Fifteen PQ-thiazolidinone derivatives, synthesized through one-post reactions from primaquine, arenealdehydes and mercaptoacetic acid, were evaluated in parallel in several biological assays, including ability to block malaria transmission to mosquitoes. Results All primaquine derivatives (PQ-TZs) exhibited lower cell toxicity than primaquine; none caused haemolysis to normal or G6PD-deficient human erythrocytes in vitro. Sera from mice pretreated with the test compounds thus assumed to have drug metabolites, caused no in vitro haemolysis of human erythrocytes, whereas sera from mice pretreated with primaquine did cause haemolysis. The ability of the PQ-TZs to block malaria transmission was evaluated based on the oocyst production and percentage of mosquitoes infected after a blood meal in drug pre-treated animals with experimental malaria caused by either Plasmodium gallinaceum or Plasmodium berghei; four and five PQ-TZs significantly inhibited sporogony in avian and in rodent malaria, respectively. Selected PQ-TZs were tested for their inhibitory activity on P. berghei liver stage development, in mice and in vitro, one compound (4m) caused a 3-day delay in the malaria pre-patent period. Conclusions The compound 4m was the most promising, blocking malaria transmissions and reducing the number of exoerythrocytic forms of P. berghei (EEFs) in hepatoma cells in vitro and in mice in vivo. The same compound also caused a 3-day delay in the malaria pre-patent period. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1755-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anna Caroline C Aguiar
- Centro de Pesquisas René Rachou-Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte, MG, 30190-002, Brazil.,Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, Belo Horizonte, MG, 30130-100, Brazil.,Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St., Baltimore, MD, 21205, USA
| | - Flávio Jr B Figueiredo
- Centro de Pesquisas René Rachou-Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte, MG, 30190-002, Brazil
| | - Patrícia D Neuenfeldt
- Laboratório de Química Aplicada à Bioativos, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, UFPel, Campus Universitário s/no, Pelotas, RS, 98001-970, Brazil
| | - Tony H Katsuragawa
- Laboratório de Epidemiologia, Fundação Osvaldo Cruz-Fiocruz Rondônia, Bairro Lagoa, Porto Velho, RO, Brazil
| | - Bruna B Drawanz
- Laboratório de Química Aplicada à Bioativos, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, UFPel, Campus Universitário s/no, Pelotas, RS, 98001-970, Brazil
| | - Wilson Cunico
- Laboratório de Química Aplicada à Bioativos, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, UFPel, Campus Universitário s/no, Pelotas, RS, 98001-970, Brazil
| | - Photini Sinnis
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St., Baltimore, MD, 21205, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St., Baltimore, MD, 21205, USA
| | - Antoniana U Krettli
- Centro de Pesquisas René Rachou-Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte, MG, 30190-002, Brazil. .,Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, Belo Horizonte, MG, 30130-100, Brazil.
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Gonçalves LA, Rodo J, Rodrigues-Duarte L, de Moraes LV, Penha-Gonçalves C. HGF Secreted by Activated Kupffer Cells Induces Apoptosis of Plasmodium-Infected Hepatocytes. Front Immunol 2017; 8:90. [PMID: 28220125 PMCID: PMC5292919 DOI: 10.3389/fimmu.2017.00090] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 01/19/2017] [Indexed: 02/03/2023] Open
Abstract
Malaria liver stage infection is an obligatory parasite development step and represents a population bottleneck in Plasmodium infections, providing an advantageous target for blocking parasite cycle progression. Parasite development inside hepatocytes implies a gross cellular insult evoking innate host responses to counteract intra-hepatocytic infection. Using primary hepatocyte cultures, we investigated the role of Kupffer cell-derived hepatocyte growth factor (HGF) in malaria liver stage infection. We found that Kupffer cells from Plasmodium-infected livers produced high levels of HGF, which trigger apoptosis of infected hepatocytes through a mitochondrial-independent apoptosis pathway. HGF action in infected hepatocyte primary cultures results in a potent reduction of parasite yield by specifically sensitizing hepatocytes carrying established parasite exo-erythrocytic forms to undergo apoptosis. This apoptosis mechanism is distinct from cell death that is spontaneously induced in infected cultures and is governed by Fas signaling modulation through a mitochondrial-dependent apoptosis pathway. This work indicates that HGF and Fas signaling pathways are part of an orchestrated host apoptosis response that occurs during malaria liver stage infection, decreasing the success of infection of individual hepatocytes. Our results raise the hypothesis that paracrine signals derived from Kupffer cell activation are implicated in directing death of hepatocytes infected with the malaria parasite.
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Affiliation(s)
| | - Joana Rodo
- Instituto Gulbenkian de Ciência , Oeiras , Portugal
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The Plasmodium falciparum Cell-Traversal Protein for Ookinetes and Sporozoites as a Candidate for Preerythrocytic and Transmission-Blocking Vaccines. Infect Immun 2017; 85:IAI.00498-16. [PMID: 27895131 PMCID: PMC5278177 DOI: 10.1128/iai.00498-16] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 11/16/2016] [Indexed: 01/04/2023] Open
Abstract
Recent studies have shown that immune responses against the cell-traversal protein for Plasmodium ookinetes and sporozoites (CelTOS) can inhibit parasite infection. While these studies provide important evidence toward the development of vaccines targeting this protein, it remains unknown whether these responses could engage the Plasmodium falciparum CelTOS in vivo. Using a newly developed rodent malaria chimeric parasite expressing the P. falciparum CelTOS (PfCelTOS), we evaluated the protective effect of in vivo immune responses elicited by vaccination and assessed the neutralizing capacity of monoclonal antibodies specific against PfCelTOS. Mice immunized with recombinant P. falciparum CelTOS in combination with the glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE) or glucopyranosyl lipid adjuvant-liposome-QS21 (GLA-LSQ) adjuvant system significantly inhibited sporozoite hepatocyte infection. Notably, monoclonal antibodies against PfCelTOS strongly inhibited oocyst development of P. falciparum and Plasmodium berghei expressing PfCelTOS in Anopheles gambiae mosquitoes. Taken together, our results demonstrate that anti-CelTOS responses elicited by vaccination or passive immunization can inhibit sporozoite and ookinete infection and impair vector transmission.
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42
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Inhibition of Plasmodium Liver Infection by Ivermectin. Antimicrob Agents Chemother 2017; 61:AAC.02005-16. [PMID: 27895022 PMCID: PMC5278742 DOI: 10.1128/aac.02005-16] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 11/18/2016] [Indexed: 12/29/2022] Open
Abstract
Avermectins are powerful endectocides with an established potential to reduce the incidence of vector-borne diseases. Here, we show that several avermectins inhibit the hepatic stage of Plasmodium infection in vitro. Notably, ivermectin potently inhibits liver infection in vivo by impairing parasite development inside hepatocytes. This impairment has a clear impact on the ensuing blood stage parasitemia, reducing disease severity and enhancing host survival. Ivermectin has been proposed as a tool to control malaria transmission because of its effects on the mosquito vector. Our study extends the effect of ivermectin to the early stages of mammalian host infection and supports the inclusion of this multipurpose drug in malaria control strategies.
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Al-Nihmi FMA, Kolli SK, Reddy SR, Mastan BS, Togiri J, Maruthi M, Gupta R, Sijwali PS, Mishra S, Kumar KA. A Novel and Conserved Plasmodium Sporozoite Membrane Protein SPELD is Required for Maturation of Exo-erythrocytic Forms. Sci Rep 2017; 7:40407. [PMID: 28067322 PMCID: PMC5220379 DOI: 10.1038/srep40407] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 12/06/2016] [Indexed: 02/07/2023] Open
Abstract
Plasmodium sporozoites are the infective forms of malaria parasite to vertebrate host and undergo dramatic changes in their transcriptional repertoire during maturation in mosquito salivary glands. We report here the role of a novel and conserved Plasmodium berghei protein encoded by PBANKA_091090 in maturation of Exo-erythrocytic Forms (EEFs) and designate it as Sporozoite surface Protein Essential for Liver stage Development (PbSPELD). PBANKA_091090 was previously annotated as PB402615.00.0 and its transcript was recovered at maximal frequency in the Serial Analysis of the Gene Expression (SAGE) of Plasmodium berghei salivary gland sporozoites. An orthologue of this transcript was independently identified in Plasmodium vivax sporozoite microarrays and was designated as Sporozoite Conserved Orthologous Transcript-2 (scot-2). Functional characterization through reverse genetics revealed that PbSPELD is essential for Plasmodium liver stage maturation. mCherry transgenic of PbSPELD localized the protein to plasma membrane of sporozoites and early EEFs. Global microarray analysis of pbspeld ko revealed EEF attenuation being associated with down regulation of genes central to general transcription, cell cycle, proteosome and cadherin signaling. pbspeld mutant EEFs induced pre-erythrocytic immunity with 50% protective efficacy. Our studies have implications for attenuating the human Plasmodium liver stages by targeting SPELD locus.
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Affiliation(s)
| | - Surendra Kumar Kolli
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Segireddy Rameswara Reddy
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Babu S Mastan
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Jyothi Togiri
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Mulaka Maruthi
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Roshni Gupta
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Puran Singh Sijwali
- CSIR-Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad 500007, India
| | - Satish Mishra
- Division of Parasitology, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Kota Arun Kumar
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
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44
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Haridas V, Ranjbar S, Vorobjev IA, Goldfeld AE, Barteneva NS. Imaging flow cytometry analysis of intracellular pathogens. Methods 2017; 112:91-104. [PMID: 27642004 PMCID: PMC5857943 DOI: 10.1016/j.ymeth.2016.09.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 08/15/2016] [Accepted: 09/15/2016] [Indexed: 01/09/2023] Open
Abstract
Imaging flow cytometry has been applied to address questions in infection biology, in particular, infections induced by intracellular pathogens. This methodology, which utilizes specialized analytic software makes it possible to analyze hundreds of quantified features for hundreds of thousands of individual cellular or subcellular events in a single experiment. Imaging flow cytometry analysis of host cell-pathogen interaction can thus quantitatively addresses a variety of biological questions related to intracellular infection, including cell counting, internalization score, and subcellular patterns of co-localization. Here, we provide an overview of recent achievements in the use of fluorescently labeled prokaryotic or eukaryotic pathogens in human cellular infections in analysis of host-pathogen interactions. Specifically, we give examples of Imagestream-based analysis of cell lines infected with Toxoplasma gondii or Mycobacterium tuberculosis. Furthermore, we illustrate the capabilities of imaging flow cytometry using a combination of standard IDEAS™ software and the more recently developed Feature Finder algorithm, which is capable of identifying statistically significant differences between researcher-defined image galleries. We argue that the combination of imaging flow cytometry with these software platforms provides a powerful new approach to understanding host control of intracellular pathogens.
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Affiliation(s)
- Viraga Haridas
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, United States; Department of Pediatrics, Harvard Medical School, United States
| | - Shahin Ranjbar
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, United States; Department of Pediatrics, Harvard Medical School, United States
| | - Ivan A Vorobjev
- School of Science and Technology, Nazarbayev University, Kazakhstan; A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Russia; Department of Cell Biology and Histology, M.V. Lomonosov Moscow State University, Russia
| | - Anne E Goldfeld
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, United States; Department of Pediatrics, Harvard Medical School, United States.
| | - Natasha S Barteneva
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, United States; Department of Pediatrics, Harvard Medical School, United States; School of Science and Technology, Nazarbayev University, Kazakhstan.
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45
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Steel RW, Kappe SH, Sack BK. An expanding toolkit for preclinical pre-erythrocytic malaria vaccine development: bridging traditional mouse malaria models and human trials. Future Microbiol 2016; 11:1563-1579. [PMID: 27855488 DOI: 10.2217/fmb-2016-0077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Malaria remains a significant public health burden with 214 million new infections and over 400,000 deaths in 2015. Elucidating relevant Plasmodium parasite biology can lead to the identification of novel ways to control and ultimately eliminate the parasite within geographic areas. Particularly, the development of an effective vaccine that targets the clinically silent pre-erythrocytic stages of infection would significantly augment existing malaria elimination tools by preventing both the onset of blood-stage infection/disease as well as spread of the parasite through mosquito transmission. In this Perspective, we discuss the role of small animal models in pre-erythrocytic stage vaccine development, highlighting how human liver-chimeric and human immune system mice are emerging as valuable components of these efforts.
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Affiliation(s)
- Ryan Wj Steel
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Stefan Hi Kappe
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Brandon K Sack
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
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46
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Distinct Prominent Roles for Enzymes of Plasmodium berghei Heme Biosynthesis in Sporozoite and Liver Stage Maturation. Infect Immun 2016; 84:3252-3262. [PMID: 27600503 DOI: 10.1128/iai.00148-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 08/29/2016] [Indexed: 11/20/2022] Open
Abstract
Malarial parasites have evolved complex regulation of heme supply and disposal to adjust to heme-rich and -deprived host environments. In addition to its own pathway for heme biosynthesis, Plasmodium likely harbors mechanisms for heme scavenging from host erythrocytes. Elaborate compartmentalization of de novo heme synthesis into three subcellular locations, including the vestigial plastid organelle, indicates critical roles in life cycle progression. In this study, we systematically profile the essentiality of heme biosynthesis by targeted gene deletion of enzymes in early steps of this pathway. We show that disruption of endogenous heme biosynthesis leads to a first detectable defect in oocyst maturation and sporogony in the Anopheles vector, whereas blood stage propagation, colonization of mosquito midguts, or initiation of oocyst development occurs indistinguishably from that of wild-type parasites. Although sporozoites are produced by parasites lacking an intact pathway for heme biosynthesis, they are absent from mosquito salivary glands, indicative of a vital role for heme biosynthesis only in sporozoite maturation. Rescue of the first defect in sporogony permitted analysis of potential roles in liver stages. We show that liver stage parasites benefit from but do not strictly depend upon their own aminolevulinic acid synthase and that they can scavenge aminolevulinic acid from the host environment. Together, our experimental genetics analysis of Plasmodium enzymes for heme biosynthesis exemplifies remarkable shifts between the use of endogenous and host resources during life cycle progression.
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47
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Hobbs CV, Anderson C, Neal J, Sahu T, Conteh S, Voza T, Langhorne J, Borkowsky W, Duffy PE. Trimethoprim-Sulfamethoxazole Prophylaxis During Live Malaria Sporozoite Immunization Induces Long-Lived, Homologous, and Heterologous Protective Immunity Against Sporozoite Challenge. J Infect Dis 2016; 215:122-130. [PMID: 28077589 DOI: 10.1093/infdis/jiw482] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 09/30/2016] [Indexed: 11/12/2022] Open
Abstract
Trimethoprim-sulfamethoxazole (TMP-SMX) is widely used in malaria-endemic areas in human immunodeficiency virus (HIV)-infected children and HIV-uninfected, HIV-exposed children as opportunistic infection prophylaxis. Despite the known effects that TMP-SMX has in reducing clinical malaria, its impact on development of malaria-specific immunity in these children remains poorly understood. Using rodent malaria models, we previously showed that TMP-SMX, at prophylactic doses, can arrest liver stage development of malaria parasites and speculated that TMP-SMX prophylaxis during repeated malaria exposures would induce protective long-lived sterile immunity targeting pre-erythrocytic stage parasites in mice. Using the same models, we now demonstrate that repeated exposures to malaria parasites during TMP-SMX administration induces stage-specific and long-lived pre-erythrocytic protective anti-malarial immunity, mediated primarily by CD8+ T-cells. Given the HIV infection and malaria coepidemic in sub-Saharan Africa, clinical studies aimed at determining the optimum duration of TMP-SMX prophylaxis in HIV-infected or HIV-exposed children must account for the potential anti-infection immunity effect of TMP-SMX prophylaxis.
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Affiliation(s)
- Charlotte V Hobbs
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland.,Division of Infectious Diseases, Department of Pediatrics.,Department of Microbiology, Batson Children's Hospital, University of Mississippi Medical Center, Jackson.,Division of Infectious Disease and Immunology, Department of Pediatrics, New York University School of Medicine
| | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
| | - Jillian Neal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
| | - Tejram Sahu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
| | - Solomon Conteh
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
| | - Tatiana Voza
- Biological Sciences Department, New York City College of Technology, City University of New York
| | - Jean Langhorne
- Mill Hill Laboratory, Francis Crick Institute, London, United Kingdom
| | - William Borkowsky
- Division of Infectious Disease and Immunology, Department of Pediatrics, New York University School of Medicine
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
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48
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Mitchell RA, Altszuler R, Frevert U, Nardin EH. Skin scarification with Plasmodium falciparum peptide vaccine using synthetic TLR agonists as adjuvants elicits malaria sporozoite neutralizing immunity. Sci Rep 2016; 6:32575. [PMID: 27624667 PMCID: PMC5021941 DOI: 10.1038/srep32575] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 08/10/2016] [Indexed: 12/19/2022] Open
Abstract
Malaria eradication will require a combination of vector control, chemotherapy and an easily administered vaccine. Sterile immunity can be elicited in humans by immunization with sporozoites, the infective stage injected by bite of the mosquito vector, however, whole parasite vaccines present formidable logistical challenges for production, storage and administration. The “gold standard” for infectious disease eradiation, the Smallpox Eradication Programme, utilized mass immunization using the skin scarification (SS) route. SS may more closely mimic the natural route of malaria infection initiated by sporozoites injected by mosquito bite which elicits both neutralizing antibodies and protective cell mediated immunity. We investigated the potential of SS immunization using a malaria repeat peptide containing a protective B cell epitope of Plasmodium falciparum, the most lethal human species, and delivery vehicles containing TLR agonists as adjuvants. In a murine model, SS immunization with peptide in combination with TLR-7/8 and -9 agonists elicited high levels of systemic sporozoite neutralizing antibody, Th1- type CD4+ T cells and resistance to challenge by bites of infected mosquitoes. SS provides the potential to elicit humoral immunity to target Plasmodium at multiple stages of its complex life cycle.
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Affiliation(s)
- Robert A Mitchell
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, NY, USA
| | - Rita Altszuler
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, NY, USA
| | - Ute Frevert
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, NY, USA
| | - Elizabeth H Nardin
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, NY, USA
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49
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Chemically Attenuated Blood-Stage Plasmodium yoelii Parasites Induce Long-Lived and Strain-Transcending Protection. Infect Immun 2016; 84:2274-2288. [PMID: 27245410 PMCID: PMC4962623 DOI: 10.1128/iai.00157-16] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 05/20/2016] [Indexed: 11/30/2022] Open
Abstract
The development of a vaccine is essential for the elimination of malaria. However, despite many years of effort, a successful vaccine has not been achieved. Most subunit vaccine candidates tested in clinical trials have provided limited efficacy, and thus attenuated whole-parasite vaccines are now receiving close scrutiny. Here, we test chemically attenuated Plasmodium yoelii 17X and demonstrate significant protection following homologous and heterologous blood-stage challenge. Protection against blood-stage infection persisted for at least 9 months. Activation of both CD4+ and CD8+ T cells was shown after vaccination; however, in vivo studies demonstrated a pivotal role for both CD4+ T cells and B cells since the absence of either cell type led to loss of vaccine-induced protection. In spite of significant activation of circulating CD8+ T cells, liver-stage immunity was not evident. Neither did vaccine-induced CD8+ T cells contribute to blood-stage protection; rather, these cells contributed to pathogenesis, since all vaccinated mice depleted of both CD4+ and CD8+ T cells survived a challenge infection. This study provides critical insight into whole-parasite vaccine-induced immunity and strong support for testing whole-parasite vaccines in humans.
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50
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Hopp CS, Balaban AE, Bushell ESC, Billker O, Rayner JC, Sinnis P. Palmitoyl transferases have critical roles in the development of mosquito and liver stages of Plasmodium. Cell Microbiol 2016; 18:1625-1641. [PMID: 27084458 DOI: 10.1111/cmi.12601] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/24/2016] [Accepted: 04/01/2016] [Indexed: 12/24/2022]
Abstract
As the Plasmodium parasite transitions between mammalian and mosquito host, it has to adjust quickly to new environments. Palmitoylation, a reversible and dynamic lipid post-translational modification, plays a central role in regulating this process and has been implicated with functions for parasite morphology, motility and host cell invasion. While proteins associated with the gliding motility machinery have been described to be palmitoylated, no palmitoyl transferase responsible for regulating gliding motility has previously been identified. Here, we characterize two palmityol transferases with gene tagging and gene deletion approaches. We identify DHHC3, a palmitoyl transferase, as a mediator of ookinete development, with a crucial role for gliding motility in ookinetes and sporozoites, and we co-localize the protein with a marker for the inner membrane complex in the ookinete stage. Ookinetes and sporozoites lacking DHHC3 are impaired in gliding motility and exhibit a strong phenotype in vivo; with ookinetes being significantly less infectious to their mosquito host and sporozoites being non-infectious to mice. Importantly, genetic complementation of the DHHC3-ko parasite completely restored virulence. We generated parasites lacking both DHHC3, as well as the palmitoyl transferase DHHC9, and found an enhanced phenotype for these double knockout parasites, allowing insights into the functional overlap and compensational nature of the large family of PbDHHCs. These findings contribute to our understanding of the organization and mechanism of the gliding motility machinery, which as is becoming increasingly clear, is mediated by palmitoylation.
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Affiliation(s)
- Christine S Hopp
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA. .,Wellcome Trust Sanger Institute, Hinxton, CB10 1SA, UK.
| | - Amanda E Balaban
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | | | | | | | - Photini Sinnis
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA.
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