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Momoh EO, Ghag SK, White J, Mudeppa DG, Rathod PK. Multiplex Assays for Analysis of Antibody Responses to South Asian Plasmodium falciparum and Plasmodium vivax Malaria Infections. Vaccines (Basel) 2023; 12:1. [PMID: 38276660 PMCID: PMC10818873 DOI: 10.3390/vaccines12010001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/01/2023] [Accepted: 12/13/2023] [Indexed: 01/27/2024] Open
Abstract
Malaria remains a major global health challenge, causing over 0.6 million yearly deaths. To understand naturally acquired immunity in adult human populations in malaria-prevalent regions, improved serological tools are needed, particularly where multiple malaria parasite species co-exist. Slide-based and bead-based multiplex approaches can help characterize antibodies in malaria patients from endemic regions, but these require pure, well-defined antigens. To efficiently bypass purification steps, codon-optimized malaria antigen genes with N-terminal FLAG-tag and C-terminal Ctag sequences were expressed in a wheat germ cell-free system and adsorbed on functionalized BioPlex beads. In a pilot study, 15 P. falciparum antigens, 8 P. vivax antigens, and a negative control (GFP) were adsorbed individually on functionalized bead types through their Ctag. To validate the multiplexing powers of this platform, 10 P. falciparum-infected patient sera from a US NIH MESA-ICEMR study site in Goa, India, were tested against all 23 parasite antigens. Serial dilution of patient sera revealed variations in potency and breadth of antibodies to various parasite antigens. Individual patients revealed informative variations in immunity to P. falciparum versus P. vivax. This multiplex approach to malaria serology captures varying immunity to different human malaria parasite species and different parasite antigens. This approach can be scaled to track the dynamics of antibody production during one or more human malaria infections.
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Affiliation(s)
| | | | | | - Devaraja G. Mudeppa
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA; (E.O.M.); (S.K.G.); (J.W.)
| | - Pradipsinh K. Rathod
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA; (E.O.M.); (S.K.G.); (J.W.)
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B-Cell Epitope Mapping of the Plasmodium falciparum Malaria Vaccine Candidate GMZ2.6c in a Naturally Exposed Population of the Brazilian Amazon. Vaccines (Basel) 2023; 11:vaccines11020446. [PMID: 36851323 PMCID: PMC9966924 DOI: 10.3390/vaccines11020446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
The GMZ2.6c malaria vaccine candidate is a multi-stage P. falciparum chimeric protein that contains a fragment of the sexual-stage Pfs48/45-6C protein genetically fused to GMZ2, an asexual-stage vaccine construction consisting of the N-terminal region of the glutamate-rich protein (GLURP) and the C-terminal region of the merozoite surface protein-3 (MSP-3). Previous studies showed that GMZ2.6c is widely recognized by antibodies from Brazilian exposed individuals and that its components are immunogenic in natural infection by P. falciparum. In addition, anti-GMZ2.6c antibodies increase with exposure to infection and may contribute to parasite immunity. Therefore, identifying epitopes of proteins recognized by antibodies may be an important tool for understanding protective immunity. Herein, we identify and validate the B-cell epitopes of GMZ2.6c as immunogenic and immunodominant in individuals exposed to malaria living in endemic areas of the Brazilian Amazon. Specific IgG antibodies and subclasses against MSP-3, GLURP, and Pfs48/45 epitopes were detected by ELISA using synthetic peptides corresponding to B-cell epitopes previously described for MSP-3 and GLURP or identified by BepiPred for Pfs48/45. The results showed that the immunodominant epitopes were P11 from GLURP and MSP-3c and DG210 from MSP-3. The IgG1 and IgG3 subclasses were preferentially induced against these epitopes, supporting previous studies that these proteins are targets for cytophilic antibodies, important for the acquisition of protective immunity. Most individuals presented detectable IgG antibodies against Pfs48/45a and/or Pfs48/45b, validating the prediction of linear B-cell epitopes. The higher frequency and antibody levels against different epitopes from GLURP, MSP-3, and Pfs48/45 provide additional information that may suggest the relevance of GMZ2.6c as a multi-stage malaria vaccine candidate.
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Oboh MA, Oyebola KM, Idowu ET, Badiane AS, Otubanjo OA, Ndiaye D. Rising report of Plasmodium vivax in sub-Saharan Africa: Implications for malaria elimination agenda. SCIENTIFIC AFRICAN 2020. [DOI: 10.1016/j.sciaf.2020.e00596] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Proietti C, Krause L, Trieu A, Dodoo D, Gyan B, Koram KA, Rogers WO, Richie TL, Crompton PD, Felgner PL, Doolan DL. Immune Signature Against Plasmodium falciparum Antigens Predicts Clinical Immunity in Distinct Malaria Endemic Communities. Mol Cell Proteomics 2020; 19:101-113. [PMID: 31658979 PMCID: PMC6944240 DOI: 10.1074/mcp.ra118.001256] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 10/23/2019] [Indexed: 01/14/2023] Open
Abstract
A large body of evidence supports the role of antibodies directed against the Plasmodium spp. parasite in the development of naturally acquired immunity to malaria, however an antigen signature capable of predicting protective immunity against Plasmodium remains to be identified. Key challenges for the identification of a predictive immune signature include the high dimensionality of data produced by high-throughput technologies and the limitation of standard statistical tests in accounting for synergetic interactions between immune responses to multiple targets. In this study, using samples collected from young children in Ghana at multiple time points during a longitudinal study, we adapted a predictive modeling framework which combines feature selection and machine learning techniques to identify an antigen signature of clinical immunity to malaria. Our results show that an individual's immune status can be accurately predicted by measuring antibody responses to a small defined set of 15 target antigens. We further demonstrate that the identified immune signature is highly versatile and capable of providing precise and accurate estimates of clinical protection from malaria in an independent geographic community. Our findings pave the way for the development of a robust point-of-care test to identify individuals at high risk of disease and which could be applied to monitor the impact of vaccinations and other interventions. This approach could be also translated to biomarker discovery for other infectious diseases.
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Affiliation(s)
- Carla Proietti
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia; QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Lutz Krause
- The University of Queensland Diamantina Institute, Brisbane, QLD, Australia
| | - Angela Trieu
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Daniel Dodoo
- Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Ben Gyan
- Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | - Kwadwo A Koram
- Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana
| | | | | | - Peter D Crompton
- Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland
| | - Philip L Felgner
- Department of Medicine, Division of Infectious Diseases, University of California Irvine, Irvine, California
| | - Denise L Doolan
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia; QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.
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5
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Antigenicity and immune correlate assessment of seven Plasmodium falciparum antigens in a longitudinal infant cohort from northern Ghana. Sci Rep 2019; 9:8621. [PMID: 31197225 PMCID: PMC6565625 DOI: 10.1038/s41598-019-45092-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/30/2019] [Indexed: 11/23/2022] Open
Abstract
The current global malaria control and elimination agenda requires development of additional effective disease intervention tools. Discovery and characterization of relevant parasite antigens is important for the development of new diagnostics and transmission monitoring tools and for subunit vaccine development. This study assessed the natural antibody response profile of seven novel Plasmodium falciparum pre-erythrocytic antigens and their potential association with protection against clinical malaria. Antigen-specific antibody levels in plasma collected at six time points from a longitudinal cohort of one-to-five year old children resident in a seasonal malaria transmission area of northern Ghana were assessed by ELISA. Antibody levels were compared between parasite-positive and parasite-negative individuals and the association of antibody levels with malaria risk assessed using a regression model. Plasma antibody levels against five of the seven antigens were significantly higher in parasite-positive children compared to parasite-negative children, especially during low transmission periods. None of the antigen-specific antibodies showed an association with protection against clinical malaria. The study identified five of the seven antigens as markers of exposure to malaria, and these will have relevance for the development of disease diagnostic and monitoring tools. The vaccine potential of these antigens requires further assessment.
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Kwenti TE, Kukwah TA, Kwenti TDB, Nyassa BR, Dilonga MH, Enow-Orock G, Tendongfor N, Anong ND, Wanji S, Njunda LA, Nkuo-Akenji T. Comparative analysis of IgG and IgG subclasses against Plasmodium falciparum MSP-1 19 in children from five contrasting bioecological zones of Cameroon. Malar J 2019; 18:16. [PMID: 30670064 PMCID: PMC6341684 DOI: 10.1186/s12936-019-2654-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 01/16/2019] [Indexed: 12/03/2022] Open
Abstract
Background Studies reporting the natural immune responses against malaria in children from different geographical settings in endemic areas are not readily available. This study was aimed at comparing the immune responses against Plasmodium falciparum MSP-119 antigen in children from five contrasting bioecological zones in Cameroon. Methods In a cross-sectional survey, children between 2 and 15 years, were enrolled from five ecological strata including the south Cameroonian equatorial forest, sudano-sahelian, high inland plateau, high western plateau, and the coastal strata. The children were screened for clinical malaria (defined by malaria parasitaemia ≥ 5000 parasites/µl plus axillary temperature ≥ 37.5 °C). Their antibody responses were measured against P. falciparum MSP-119 antigen using standard ELISA technique. Results In all, 415 children comprising 217 (52.3%) males participated. Total IgG and IgG1–IgG4 titres were observed to increase with age in all the strata except in the sudano-sahelian and high inland plateau strata. Total IgG and IgG1–IgG4 titres were significantly higher in the coastal strata and lowest in the high inland plateau (for IgG1 and IgG2) and sudano-sahelian strata (for IgG3 and IgG4). Titres of the cytophilic antibodies (IgG1 and IgG3) were significantly higher than the non-cytophilic antibodies (IgG2 and IgG4) in all the strata except in the sudano-sahelian and high inland plateau strata. Total IgG and IgG subclass titres were significantly higher in children positive for clinical malaria compared to negative children in all study sites except in the high western plateau and coastal (for IgG1 and IgG3), and the sudano-sahelian strata (for all antibodies). Furthermore, a significant positive correlation was observed between parasite density and IgG2 or IgG4 titres in all study sites except in the south Cameroonian equatorial forest and sudano-sahelian strata. Conclusions This study showed that antibody responses against MSP-119 vary considerably in children from the different bioecological strata in Cameroon and could be linked to the differential exposure to malaria in the different strata. Furthermore, the rate of antibody acquisition was not observed to increase in an age-dependent manner in low transmission settings. Electronic supplementary material The online version of this article (10.1186/s12936-019-2654-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tebit Emmanuel Kwenti
- Department of Medical Laboratory Sciences, Faculty of Health Science, University of Buea, P.O. Box 23, Buea, Southwest Region, Cameroon. .,Regional Hospital of Buea, P.O. Box 32, Buea, Southwest Region, Cameroon. .,Department of Public Health and Hygiene, Faculty of Health Science, University of Buea, P.O. Box 23, Buea, Southwest Region, Cameroon. .,Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon.
| | - Tufon Anthony Kukwah
- Regional Hospital of Buea, P.O. Box 32, Buea, Southwest Region, Cameroon.,Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon
| | - Tayong Dizzle Bita Kwenti
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon
| | - Babila Raymond Nyassa
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon
| | - Meriki Henry Dilonga
- Regional Hospital of Buea, P.O. Box 32, Buea, Southwest Region, Cameroon.,Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon
| | - George Enow-Orock
- Regional Hospital of Buea, P.O. Box 32, Buea, Southwest Region, Cameroon.,Department of Biomedical Science, Faculty of Health Science, University of Buea, P.O Box 23, Buea, Southwest Region, Cameroon
| | - Nicholas Tendongfor
- Department of Public Health and Hygiene, Faculty of Health Science, University of Buea, P.O. Box 23, Buea, Southwest Region, Cameroon.,Department of Microbiology and Parasitology, Faculty of Science, University of Buea, P.O. Box 63, Buea, Southwest Region, Cameroon
| | - Nota Damian Anong
- Department of Biological Science, Faculty of Science, University of Bamenda, Bamenda, North West Region, Cameroon
| | - Samuel Wanji
- Parasites and Vector Biology Research Unit, Department of Microbiology and Parasitology, University of Buea, Buea, Cameroon
| | - Longdoh Anna Njunda
- Department of Medical Laboratory Sciences, Faculty of Health Science, University of Buea, P.O. Box 23, Buea, Southwest Region, Cameroon
| | - Theresa Nkuo-Akenji
- Department of Biological Science, Faculty of Science, University of Bamenda, Bamenda, North West Region, Cameroon
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Ondigo BN, Park GS, Ayieko C, Nyangahu DD, Wasswa R, John CC. Comparison of non-magnetic and magnetic beads multiplex assay for assessment of Plasmodium falciparum antibodies. PeerJ 2019; 7:e6120. [PMID: 30627487 PMCID: PMC6321751 DOI: 10.7717/peerj.6120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 11/16/2018] [Indexed: 11/20/2022] Open
Abstract
Background New reagents have emerged allowing researchers to assess a growing number of vaccine-associated immune parameters. Multiplex immunoassay(s) are emerging as efficient high-throughput assays in malaria serology. Currently, commercial vendors market several bead reagents for cytometric bead assays (CBA) but relative performances are not well published. We have compared two types of bead-based multiplex assays to measure relative antibody levels to malarial antigens. Methods Assays for the measurement of antibodies to five Plasmodium falciparum vaccine candidates using non-magnetic and magnetic fluorescent microspheres were compared for their performances with a Bio-Plex200 instrument. Mean fluorescence intensity (MFI) was determined from individuals from western Kenya and compared to known positive and negative control plasma samples. Results P. falciparum recombinant antigens were successfully coupled to both non-magnetic and magnetic beads in multiplex assays. MFIs between the two bead types were comparable for all antigens tested. Bead recovery was superior with magnetic beads for all antigens. MFI values of stored non-magnetic coupled beads did not differ from freshly coupled beads, though they showed higher levels of bead aggregation. Discussion Magnetic and non-magnetic beads performed similarly in P. falciparum antibody assays. Magnetic beads were more expensive, but had higher bead recovery, were more convenient to use, and provided rapid and easy protocol manipulation. Magnetic beads are a suitable alternative to non-magnetic beads in malarial antibody serology.
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Affiliation(s)
- Bartholomew N Ondigo
- Department of Biochemistry and Molecular Biology, Egerton University, Nakuru, Kenya.,Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Gregory S Park
- Office of the Vice President for Research, University of Minnesota, Minneapolis, MN, USA
| | - Cyrus Ayieko
- Department of Zoology, Maseno University, Kisumu, Kenya
| | - Donald D Nyangahu
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA.,Department of Pediatrics, University of Washington, Seattle, WA, USA
| | | | - Chandy C John
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya.,Ryan White Center for Pediatric Infectious Diseases and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
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8
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Optimization of a magnetic bead-based assay (MAGPIX ®-Luminex) for immune surveillance of exposure to malaria using multiple Plasmodium antigens and sera from different endemic settings. Malar J 2018; 17:324. [PMID: 30189885 PMCID: PMC6127931 DOI: 10.1186/s12936-018-2465-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 08/27/2018] [Indexed: 01/08/2023] Open
Abstract
Background Serological markers are potentially useful tools for monitoring the progress of malaria control programs, but a better understanding of antibody response dynamics is necessary. The use of a magnetic bead-based immunoassay (MBA) is advantageous compared to ELISA, due to its multiplexing capacity, but limited information is available on the standardization and validation of this assay. Methods Several parameters for multiplex testing of antibodies to Plasmodium antigens were analysed using a set of 4 antigens and 98 sera from Senegalese rural asymptomatic and urban symptomatic individuals. The 4 antigens included Plasmodium falciparum CSP and PfAMA1 peptides, recombinant P. falciparum MSP4p20 and a Plasmodium malariae CSP (PmCSP) peptide. Comparisons with ELISA were done using MSP4p20 and whole schizont extract (SE) antigens. Results The use of fewer beads (1000 beads per well instead of 2000) and 5 µg of antigen per 106 bead were validated as lower amounts. The use of a carrier protein (BSA) was shown to be critical when using peptides and the effect of a 24 h delayed measures was evaluated (5–25% signal decrease). Analysis of Ab responses showed almost equally high levels and prevalence in all transmission settings. Clear distinctions between rural and urban malaria were noted using PmCSP and SE antigens. Conclusions This study underlines the importance of further optimization of the MBA technique and highlights the interest of using multistage/multispecies antigens for surveillance of malaria in endemic settings.
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Ademolue TW, Awandare GA. Evaluating antidisease immunity to malaria and implications for vaccine design. Immunology 2017; 153:423-434. [PMID: 29211303 PMCID: PMC5838420 DOI: 10.1111/imm.12877] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 11/24/2017] [Accepted: 11/27/2017] [Indexed: 12/29/2022] Open
Abstract
Immunity to malaria could be categorized broadly as antiparasite or antidisease immunity. While most vaccine research efforts have focused on antiparasite immunity, the evidence from endemic populations suggest that antidisease immunity is an important component of natural immunity to malaria. The processes that mediate antidisease immunity have, however, attracted little to no attention, and most interests have been directed towards the antibody responses. This review evaluates the evidence for antidisease immunity in endemic areas and discusses the possible mechanisms responsible for it. Given the key role that inflammation plays in the pathogenesis of malaria, regulation of the inflammatory response appears to be a major mechanism for antidisease immunity in naturally exposed individuals.
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Affiliation(s)
- Temitope W Ademolue
- West African Center for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana
| | - Gordon A Awandare
- West African Center for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana
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10
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Kwenti TE, Moye AL, Wiylanyuy AB, Njunda LA, Nkuo-Akenji T. Variation in the immune responses against Plasmodium falciparum merozoite surface protein-1 and apical membrane antigen-1 in children residing in the different epidemiological strata of malaria in Cameroon. Malar J 2017; 16:453. [PMID: 29121929 PMCID: PMC5679504 DOI: 10.1186/s12936-017-2105-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 11/02/2017] [Indexed: 11/12/2022] Open
Abstract
Background Studies to assess the immune responses against malaria in Cameroonian children are limited. The purpose of this study was to assess the immune responses against Plasmodium falciparum merozoite surface protein-1 (MSP-119) and apical membrane antigen-1 (AMA-1) in children residing in the different epidemiological strata of malaria in Cameroon. Methods In a cross-sectional survey performed between April and July 2015, 602 children between 2 and 15 years (mean ± SD = 5.7 ± 3.7), comprising 319 (53%) males were enrolled from five epidemiological strata of malaria in Cameroon including: the sudano-sahelian (SS) strata, the high inland plateau (HIP) strata, the south Cameroonian equatorial forest (SCEF) strata, the high western plateau (HWP) strata, and the coastal (C) strata. The children were screened for clinical malaria (defined by malaria parasitaemia ≥ 5000 parasites/µl plus axillary temperature ≥ 37.5 °C). Their antibody responses were measured against P. falciparum MSP-119 and AMA-1 vaccine candidate antigens using standard ELISA technique. Results A majority of the participants were IgG responders 72.1% (95% CI 68.3–75.6). The proportion of responders was higher in females (p = 0.002) and in children aged 10 years and above (p = 0.005). The proportion of responders was highest in Limbe (C strata) and lowest in Ngaoundere (HIP strata) (p < 0.0001). Similarly, the mean IgG antibody levels were higher in children aged 10 years and above (p < 0.0001) and in Limbe (p = 0.001). The IgG antibody levels against AMA-1 were higher in females (p = 0.028), meanwhile no gender disparity was observed with MSP-1. Furthermore the risk of clinical malaria (p < 0.0001) and the mean parasite density (p = 0.035) were higher in IgG non-responders. Conclusion A high proportion of IgG responders was observed in this study, suggesting a high degree exposure of the target population to malaria parasites. The immune responses varied considerably across the different strata: the highest levels observed in the C strata and the lowest in the HIP strata. Furthermore, malaria transmission in Cameroon could be categorized into two major groups based on the serological reaction of the children: the southern (comprising C and SCEF strata) and northern (comprising HWP, HIP and SS strata) groups. These findings may have significant implications in the design of future trials for evaluating malaria vaccine candidates in Cameroon.
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Affiliation(s)
- Tebit Emmanuel Kwenti
- Department of Microbiology and Parasitology, University of Buea, P.B. 63, Buea, Cameroon. .,Department of Medical Laboratory Sciences, University of Buea, P.B. 63, Buea, Cameroon.
| | | | | | - Longdoh Anna Njunda
- Department of Microbiology and Parasitology, University of Buea, P.B. 63, Buea, Cameroon
| | - Theresa Nkuo-Akenji
- Department of Microbiology and Parasitology, University of Buea, P.B. 63, Buea, Cameroon
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11
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Aguilar R, Casabonne D, O’Callaghan-Gordo C, Vidal M, Campo JJ, Mutalima N, Angov E, Dutta S, Gaur D, Chitnis CE, Chauhan V, Michel A, de Sanjosé S, Waterboer T, Kogevinas M, Newton R, Dobaño C. Assessment of the Combined Effect of Epstein-Barr Virus and Plasmodium falciparum Infections on Endemic Burkitt Lymphoma Using a Multiplex Serological Approach. Front Immunol 2017; 8:1284. [PMID: 29123514 PMCID: PMC5662586 DOI: 10.3389/fimmu.2017.01284] [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: 07/24/2017] [Accepted: 09/25/2017] [Indexed: 12/30/2022] Open
Abstract
Epstein-Barr virus (EBV) is a necessary cause of endemic Burkitt lymphoma (eBL), while the role of Plasmodium falciparum in eBL remains uncertain. This study aimed to generate new hypotheses on the interplay between both infections in the development of eBL by investigating the IgG and IgM profiles against several EBV and P. falciparum antigens. Serum samples collected in a childhood study in Malawi (2005-2006) from 442 HIV-seronegative children (271 eBL cases and 171 controls) between 1.4 and 15 years old were tested by quantitative suspension array technology against a newly developed multiplex panel combining 4 EBV antigens [Z Epstein-Barr replication activator protein (ZEBRA), early antigen-diffuse component (EA-D), EBV nuclear antigen 1, and viral capsid antigen p18 subunit (VCA-p18)] and 15 P. falciparum antigens selected for their immunogenicity, role in malaria pathogenesis, and presence in different parasite stages. Principal component analyses, multivariate logistic models, and elastic-net regressions were used. As expected, elevated levels of EBV IgG (especially against the lytic antigens ZEBRA, EA-D, and VCA-p18) were strongly associated with eBL [high vs low tertile odds ratio (OR) = 8.67, 95% confidence interval (CI) = 4.81-15.64]. Higher IgG responses to the merozoite surface protein 3 were observed in children with eBL compared with controls (OR = 1.29, 95% CI = 1.02-1.64), showing an additive interaction with EBV IgGs (OR = 10.6, 95% CI = 5.1-22.2, P = 0.05). Using elastic-net regression models, eBL serological profile was further characterized by lower IgM levels against P. falciparum preerythrocytic-stage antigen CelTOS and EBV lytic antigen VCA-p18 compared with controls. In a secondary analysis, abdominal Burkitt lymphoma had lower IgM to EBV and higher IgG to EA-D levels than cases with head involvement. Overall, this exploratory study confirmed the strong role of EBV in eBL and identified differential IgG and IgM patterns to erythrocytic vs preerythrocytic P. falciparum antigens that suggest a more persistent/chronic malaria exposure and a weaker IgM immune response in children with eBL compared with controls. Future studies should continue exploring how the malaria infection status and the immune response to P. falciparum interact with EBV infection in the development of eBL.
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Affiliation(s)
- Ruth Aguilar
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Delphine Casabonne
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Unit of Infections and Cancer, Cancer Epidemiology Research Programme, IDIBELL, Institut Català d’Oncologia, L’Hospitalet de Llobregat, Spain
| | - Cristina O’Callaghan-Gordo
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Marta Vidal
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Joseph J. Campo
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Nora Mutalima
- Department of Orthopaedic Surgery, Monash Health, Melbourne, VIC, Australia
- Department of Surgery, School of Clinical Sciences, Monash University, Melbourne, VIC, Australia
| | | | | | - Deepak Gaur
- ICGEB, Delhi, India
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | | | | | | | - Silvia de Sanjosé
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Unit of Infections and Cancer, Cancer Epidemiology Research Programme, IDIBELL, Institut Català d’Oncologia, L’Hospitalet de Llobregat, Spain
| | - Tim Waterboer
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Manolis Kogevinas
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - Rob Newton
- Epidemiology and Cancer Statistics Group, University of York, York, United Kingdom
- MRC/UVRI Uganda Research Unit on AIDS, Entebbe, Uganda
| | - Carlota Dobaño
- ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
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12
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Kusi KA, Manu EA, Manful Gwira T, Kyei-Baafour E, Dickson EK, Amponsah JA, Remarque EJ, Faber BW, Kocken CHM, Dodoo D, Gyan BA, Awandare GA, Atuguba F, Oduro AR, Koram KA. Variations in the quality of malaria-specific antibodies with transmission intensity in a seasonal malaria transmission area of Northern Ghana. PLoS One 2017; 12:e0185303. [PMID: 28945794 PMCID: PMC5612719 DOI: 10.1371/journal.pone.0185303] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 09/11/2017] [Indexed: 02/07/2023] Open
Abstract
Introduction Plasmodium falciparum induced antibodies are key components of anti-malarial immunity in malaria endemic areas, but their antigen targets can be polymorphic. Induction of a high proportion of strain-specific antibodies will limit the recognition of a broad diversity of parasite strains by these responses. There are indications that circulating parasite diversity varies with malaria transmission intensity, and this may affect the specificity of elicited anti-malarial antibodies. This study therefore assessed the effect of varying malaria transmission patterns on the specificity of elicited antibody responses and to identify possible antibody correlates of naturally acquired immunity to malaria in children in an area of Ghana with seasonal malaria transmission. Methods This retrospective study utilized plasma samples collected longitudinally at six time points from children aged one to five years. Multiplex assays were used to measure antibody levels against four P. falciparum AMA 1 variants (from the 3D7, FVO, HB3 and CAMP parasite strains) and the 3D7 variant of the EBA 175 region II antigen and the levels compared between symptomatic and asymptomatic children. The relative proportions of cross-reactive and strain-specific antibodies against the four AMA 1 variants per sampling time point were assessed by Bland-Altman plots. The levels of antibodies against allelic AMA1 variants, measured by singleplex and multiplex luminex assays, were also compared. Results The data show that increased transmission intensity is associated with higher levels of cross-reactive antibody responses, most likely a result of a greater proportion of multiple parasite clone infections during the high transmission period. Anti-AMA1 antibodies were however associated with a history of infection rather than protection in this age group. Conclusion The data contribute to understanding the underlying mechanism of the acquisition of strain-transcending antibody immunity following repeated exposure to diverse parasite strains.
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Affiliation(s)
- Kwadwo A. Kusi
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- * E-mail:
| | - Emmanuel A. Manu
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
| | - Theresa Manful Gwira
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
| | - Eric Kyei-Baafour
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Emmanuel K. Dickson
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Jones A. Amponsah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Edmond J. Remarque
- Department of Parasitology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Bart W. Faber
- Department of Parasitology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Clemens H. M. Kocken
- Department of Parasitology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Daniel Dodoo
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Ben A. Gyan
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Gordon A. Awandare
- Department of Biochemistry, Cell and Molecular Biology, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
| | - Frank Atuguba
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Abraham R. Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Kwadwo A. Koram
- West African Centre for Cell Biology of Infectious Pathogens, College of Basic and Applied Sciences, University of Ghana, Legon, Ghana
- Department of Epidemiology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
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13
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Fang R, Wey A, Bobbili NK, Leke RFG, Taylor DW, Chen JJ. An analytical approach to reduce between-plate variation in multiplex assays that measure antibodies to Plasmodium falciparum antigens. Malar J 2017; 16:287. [PMID: 28716094 PMCID: PMC5513105 DOI: 10.1186/s12936-017-1933-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/11/2017] [Indexed: 11/29/2022] Open
Abstract
Background Antibodies play an important role in immunity to malaria. Recent studies show that antibodies to multiple antigens, as well as, the overall breadth of the response are associated with protection from malaria. Yet, the variability and reliability of antibody measurements against a combination of malarial antigens using multiplex assays have not been well characterized. Methods A normalization procedure for reducing between-plate variation using replicates of pooled positive and negative controls was investigated. Sixty test samples (30 from malaria-positive and 30 malaria-negative individuals), together with five pooled positive-controls and two pooled negative-controls, were screened for antibody levels to 9 malarial antigens, including merozoite antigens (AMA1, EBA175, MSP1, MSP2, MSP3, MSP11, Pf41), sporozoite CSP, and pregnancy-associated VAR2CSA. The antibody levels were measured in triplicate on each of 3 plates, and the experiments were replicated on two different days by the same technician. The performance of the proposed normalization procedure was evaluated with the pooled controls for the test samples on both the linear and natural-log scales. Results Compared with data on the linear scale, the natural-log transformed data were less skewed and reduced the mean–variance relationship. The proposed normalization procedure using pooled controls on the natural-log scale significantly reduced between-plate variation. Conclusions For malaria-related research that measure antibodies to multiple antigens with multiplex assays, the natural-log transformation is recommended for data analysis and use of the normalization procedure with multiple pooled controls can improve the precision of antibody measurements. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1933-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rui Fang
- Office of Biostatistics and Quantitative Health Sciences, University of Hawaii John A. Burns School of Medicine, Honolulu, HI, 96813, USA
| | - Andrew Wey
- Office of Biostatistics and Quantitative Health Sciences, University of Hawaii John A. Burns School of Medicine, Honolulu, HI, 96813, USA
| | - Naveen K Bobbili
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, University of Hawaii John A. Burns School of Medicine, 651 Ilalo Street, BSB 211, Honolulu, HI, 96813, USA
| | - Rose F G Leke
- Biotechnology Center, Faculty of Medicine and Biomedical Research, University of Yaounde 1, Yaounde, Cameroon
| | - Diane Wallace Taylor
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, University of Hawaii John A. Burns School of Medicine, 651 Ilalo Street, BSB 211, Honolulu, HI, 96813, USA
| | - John J Chen
- Office of Biostatistics and Quantitative Health Sciences, University of Hawaii John A. Burns School of Medicine, Honolulu, HI, 96813, USA.
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14
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Imboumy-Limoukou RK, Oyegue-Liabagui SL, Ndidi S, Pegha-Moukandja I, Kouna CL, Galaway F, Florent I, Lekana-Douki JB. Comparative Antibody Responses Against three Antimalarial Vaccine Candidate Antigens from Urban and Rural Exposed Individuals in Gabon. Eur J Microbiol Immunol (Bp) 2016; 6:287-297. [PMID: 27980857 PMCID: PMC5146647 DOI: 10.1556/1886.2016.00027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 08/15/2016] [Indexed: 12/12/2022] Open
Abstract
The analysis of immune responses in diverse malaria endemic regions provides more information to understand the host's immune response to Plasmodium falciparum. Several plasmodial antigens have been reported as targets of human immunity. PfAMA1 is one of most studied vaccine candidates; PfRH5 and Pf113 are new promising vaccine candidates. The aim of this study was to evaluate humoral response against these three antigens among children of Lastourville (rural area) and Franceville (urban area). Malaria was diagnosed using rapid diagnosis tests. Plasma samples were tested against these antigens by enzyme-linked immunosorbent assay (ELISA). We found that malaria prevalence was five times higher in the rural area than in the urban area (p < 0.0001). The anti-PfAMA1 and PfRh5 response levels were significantly higher in Lastourville than in Franceville (p < 0.0001; p = 0.005). The anti-AMA1 response was higher than the anti-Pf113 response, which in turn was higher than the anti-PfRh5 response in both sites. Anti-PfAMA1 levels were significantly higher in infected children than those in uninfected children (p = 0.001) in Franceville. Anti-Pf113 and anti-PfRh5 antibody levels were lowest in children presenting severe malarial anemia. These three antigens are targets of immunity in Gabon. Further studies on the role of Pf113 in antimalarial protection against severe anemia are needed.
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Affiliation(s)
- Roméo-Karl Imboumy-Limoukou
- Unité de Parasitologie Médicale (UPARAM), Centre International de Recherches Médicales de Franceville (CIRMF), BP 769 Franceville, Gabon; Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245), Sorbonne Universités, Muséum National d'Histoire Naturelle, CNRS, CP52, 57 rue Cuvier 75005 Paris, France; Ecole Doctorale Régionale en Infectiologie Tropicale d'Afrique Centrale (ECODRAC), BP 876 Franceville, Gabon
| | - Sandrine Lydie Oyegue-Liabagui
- Laboratoire de Recherches en Immunologie, Parasitologie et Microbiologie, Ecole Doctorale Régionale en Infectiologie Tropicale d'Afrique Centrale (ECODRAC) , BP 876 Franceville, Gabon
| | - Stella Ndidi
- Unité de Parasitologie Médicale (UPARAM), Centre International de Recherches Médicales de Franceville (CIRMF) , BP 769 Franceville, Gabon
| | - Irène Pegha-Moukandja
- Unité de Parasitologie Médicale (UPARAM), Centre International de Recherches Médicales de Franceville (CIRMF), BP 769 Franceville, Gabon; Ecole Doctorale Régionale en Infectiologie Tropicale d'Afrique Centrale (ECODRAC), BP 876 Franceville, Gabon
| | - Charlene Lady Kouna
- Unité de Parasitologie Médicale (UPARAM), Centre International de Recherches Médicales de Franceville (CIRMF) , BP 769 Franceville, Gabon
| | | | - Isabelle Florent
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245), Sorbonne Universités, Muséum National d'Histoire Naturelle, CNRS, CP52 , 57 rue Cuvier 75005 Paris, France
| | - Jean Bernard Lekana-Douki
- Unité de Parasitologie Médicale (UPARAM), Centre International de Recherches Médicales de Franceville (CIRMF), BP 769 Franceville, Gabon; Département de Parasitologie-Mycologie, Université des Sciences de la Santé, BP 4008 Libreville, Gabon
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15
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Kalra A, Edula JR, Gupta PK, Pandey AK, Chauhan VS. Antigenicity of a Bacterially Expressed Triple Chimeric Antigen of Plasmodium falciparum AARP, MSP-311 and MSP-119: PfAMSP-Fu35. PLoS One 2016; 11:e0165720. [PMID: 27798691 PMCID: PMC5087855 DOI: 10.1371/journal.pone.0165720] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 10/17/2016] [Indexed: 01/18/2023] Open
Abstract
Development of fusion chimeras as potential vaccine candidates is considered as an attractive strategy to generate effective immune responses to more than one antigen using a single construct. Here, we described the design, production, purification and antigenicity of a fusion chimera (PfAMSP-Fu35), comprised of immunologically relevant regions of three vaccine target malaria antigens, PfAARP, PfMSP-3 and PfMSP-1. The recombinant PfAMSP-Fu35 is expressed as a soluble protein and purified to homogeneity with ease at a yield of ~ 7 mg L-1. Conformational integrity of the C-terminal fragment of PfMSP-1, PfMSP-119 was retained in the fusion chimera as shown by ELISA with conformation sensitive monoclonal antibodies. High titre antibodies were raised to the fusion protein and to all the three individual components in mice and rabbits upon immunization with fusion chimera in two different adjuvant formulations. The sera against PfAMSP-Fu35 recognized native parasite proteins corresponding to the three components of the fusion chimera. As shown by invasion inhibition assay and antibody mediated cellular inhibition assay, antibodies purified from the PfAMSP-Fu35 immunized serum successfully and efficiently inhibited parasite invasion in P. falciparum 3D7 in vitro both directly and in monocyte dependent manner. However, the invasion inhibitory activity of anti-AMSP-Fu35 antibody is not significantly enhanced as expected as compared to a previously described two component fusion chimera, MSP-Fu24. Therefore, it may not be of much merit to consider AMSP-Fu35 as a vaccine candidate for preclinical development.
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Affiliation(s)
- Aakanksha Kalra
- Malaria Research Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Jyotheeswara Reddy Edula
- Malaria Research Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Puneet Kumar Gupta
- Malaria Research Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Alok Kumar Pandey
- Malaria Research Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Virander S. Chauhan
- Malaria Research Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
- * E-mail: ;
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16
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Mbengue B, Kpodji P, Sylla Niang M, Varela ML, Thiam A, Sow A, Ndiaye K, Aidara M, Thiam F, Ndiaye R, Diop G, Nguer CM, Perraut R, Dièye A. [Profiles of IgG responses against CSP, GLURP and LSA-3NR2 in urban malaria (Dakar): relations with haemoglobin levels and parasite densities]. BULLETIN DE LA SOCIETE DE PATHOLOGIE EXOTIQUE (1990) 2016; 109:91-98. [PMID: 27100862 DOI: 10.1007/s13149-016-0485-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/23/2016] [Indexed: 06/05/2023]
Abstract
Malaria remains a major health problem in sub- Saharan African countries despite substantial decreases in morbidity and mortality due to sustained control programs. Vaccines candidates were mainly tested in rural endemic setting; however increasing proportion of the population is living in urban area. Evaluation of the qualitative or quantitative immune responses to key targets of anti-Plasmodium immunity requires further investigation in urban area. In a cohort of 144 patients with mild malaria living in Dakar, we analyzed IgG responses against target antigens of P. falciparum: CSP, LSA-3NR2 and GLURP by ELISA. A mean age of 15 yrs (4-65 yrs) was found and patients were separated in 59 adults (<15yrs) and 85 children (≤15 yrs). Parasites densities (0,01-15%) did not differ between the two age groups. In contrast, haemoglobin levels appeared lower in children (4.5-16.6 g/dl) (p<0.01). For the immune results, the most recognized antigens were GLURP and CSP compared to LSA-3NR2. Levels of IgG against these antigens were significantly different between the two age groups and they were positively correlated (rho = 0.32; p<0.001). In addition, levels of IgG anti-GLURP were associated with low parasitemia (≤1%) and absence of anemia (≥11g/dl), particularly in adults (p<0.001). In a multiple regression analysis, no significant relationship was found between parasite densities and IgG responses against all the tested antigens. Our study shows the implication of IgG anti-GLURP in humoral immune response against the parasite. The present work contributes to determine IgG levels that can be used as relevant immunologic biomarkers in urban clinical malaria.
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Affiliation(s)
- B Mbengue
- Service d'immunologie FMPO, Université Cheikh Anta Diop, Dakar, Sénégal.
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal.
| | - P Kpodji
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - M Sylla Niang
- Service d'immunologie FMPO, Université Cheikh Anta Diop, Dakar, Sénégal
| | - M L Varela
- Unité d'immunologie, Institut Pasteur de Dakar, Dakar, Sénégal
| | - A Thiam
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - A Sow
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - K Ndiaye
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - M Aidara
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - F Thiam
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - R Ndiaye
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - G Diop
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
| | - C M Nguer
- Département génie chimique et biologie appliquée, ESP, Université Cheikh Anta Diop, Dakar, Sénégal
| | - R Perraut
- Unité d'immunologie, Institut Pasteur de Dakar, Dakar, Sénégal
| | - A Dièye
- Unité d'immunogénétique, Institut Pasteur de Dakar, Dakar, Sénégal
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17
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Longwe H, Jambo KC, Phiri KS, Mbeye N, Gondwe T, Hall T, Tetteh KKA, Drakeley C, Mandala WL. The effect of daily co-trimoxazole prophylaxis on natural development of antibody-mediated immunity against P. falciparum malaria infection in HIV-exposed uninfected Malawian children. PLoS One 2015; 10:e0121643. [PMID: 25807475 PMCID: PMC4373908 DOI: 10.1371/journal.pone.0121643] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/02/2015] [Indexed: 11/24/2022] Open
Abstract
Background and Objectives Co-trimoxazole prophylaxis, currently recommended in HIV-exposed, uninfected (HEU) children as protection against opportunistic infections, also has some anti-malarial efficacy. We determined whether daily co-trimoxazole prophylaxis affects the natural development of antibody-mediated immunity to blood-stage Plasmodium falciparum malaria infection. Methods Using an enzyme-linked immunosorbent assay, we measured antibodies to 8Plasmodium falciparum antigens (AMA-1, MSP-119, MSP-3, PfSE, EBA-175RII, GLURP R0, GLURP R2 and CSP) in serum samples from 33 HEU children and 31 HIV-unexposed, uninfected (HUU) children, collected at 6, 12 and 18 months of age. Results Compared to HIV-uninfected children, HEU children had significantly lower levels of specific IgG against AMA-1 at 6 months (p = 0.001), MSP-119 at 12 months (p = 0.041) and PfSE at 6 months (p = 0.038), 12 months (p = 0.0012) and 18 months (p = 0.0097). No differences in the IgG antibody responses against the rest of the antigens were observed between the two groups at all time points. The breadth of specificity of IgG response was reduced in HEU children compared to HUU children during the follow up period. Conclusions Co-trimoxazole prophylaxis seems to reduce IgG antibody responses to P. falciparum blood stage antigens, which could be as a result of a reduction in exposure of those children under this regime. Although antibody responses were regarded as markers of exposure in this study, further studies are required to establish whether these responses are correlated in any way to clinical immunity to malaria.
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Affiliation(s)
- Herbert Longwe
- Department of Basic Medical Sciences, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Kondwani C. Jambo
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Kamija S. Phiri
- Tropical Haematology Research Unit, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Nyanyiwe Mbeye
- Department of Public Health, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Thandile Gondwe
- Department of Public Health, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Tom Hall
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Wilson L. Mandala
- Department of Basic Medical Sciences, College of Medicine, University of Malawi, Blantyre, Malawi
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- * E-mail:
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18
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Mbengue B, Sylla Niang M, Ndiaye Diallo R, Diop G, Thiam A, Ka O, Touré A, Tall A, Perraut R, Dièye A. [IgG responses to candidate malaria vaccine antigens in the urban area of Dakar (Senegal): evolution according to age and parasitemia in patients with mild symptoms]. ACTA ACUST UNITED AC 2015; 108:94-101. [PMID: 25925805 DOI: 10.1007/s13149-015-0419-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 11/25/2014] [Indexed: 12/22/2022]
Abstract
Malaria remains a major problem in African countries despite substantial decreases in morbidity and mortality due to sustained control programs. Studies for the evaluation of qualitative or quantitative Ab responses to key targets of anti-plasmodium immunity were mostly done in rural endemic setting compared to urban area. In a cohort of 200 patients with mild malaria and living in Dakar, we analyze total and subclasses IgG responses to a panel of P. falciparum blood stage antigens: MSP1p19, MSP3, EB200, GST-5 and R23. A mean age of 15 yrs (4 to 56 yrs) and parasitemia between 0.1 to 17% were found. Levels of IgG anti-MSP3 were higher in patients with low parasitemia (≤1%) and appear negatively correlated to parasite densities (Rho =. 0.54; p= 0.021). This correlation is more significant in children (≤ 15 yrs). In addition, an increase of IgG responses against MSP1p19 is highly observed in adults having a parasitemia less than 1%. In those patients, we find that IgG1 subclasses were predominant (p <0.01). Our study shows an association between Ab responses and parasitemia. This association is dependant to IgG anti-MSP3 in children and IgG anti-MSP1p19 in adults living in urban area.
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Affiliation(s)
- B Mbengue
- Service d'immunologie UCAD FMPO, Dakar, Sénégal,
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19
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Perraut R, Richard V, Varela ML, Trape JF, Guillotte M, Tall A, Toure A, Sokhna C, Vigan-Womas I, Mercereau-Puijalon O. Comparative analysis of IgG responses to Plasmodium falciparum MSP1p19 and PF13-DBL1α1 using ELISA and a magnetic bead-based duplex assay (MAGPIX®-Luminex) in a Senegalese meso-endemic community. Malar J 2014; 13:410. [PMID: 25326042 PMCID: PMC4221706 DOI: 10.1186/1475-2875-13-410] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/09/2014] [Indexed: 01/16/2023] Open
Abstract
Background Numerous Plasmodium falciparum antigens elicit humoral responses in humans living in endemic areas. Use of multiplex assays is a convenient approach to monitor the antibody response against multiple antigens, but to integrate multiplex assay-derived data with datasets, generated previously using ELISA, comparative studies are needed. This work compares antibody responses to two P. falciparum antigens monitored using both technologies. Methods The IgG response against the merozoite surface protein-1 PfMSP1p19 and the PF13-DBL1α1 domain of the P. falciparum Erythrocyte Membrane Protein1, expressed by the rosette-forming parasite 3D7/PF13 (PF13), was investigated using ELISA and a MAGPIX®-Luminex duplex assay. Archived plasma samples collected before the rainy season from 217 villagers living in Ndiop, a Senegalese meso-endemic setting, were studied. ROC analysis was used to define the optimal antibody measure readout. Association of antibody levels with protection against clinical malaria was analysed using Poisson regression in a retrospective study from active case detection records performed during the 5.5-month transmission season that followed blood sampling. Results There was a strong positive correlation (P <10-3) between ELISA and MAGPIX®-Luminex-MFI (median fluorescence intensity) values for antibody to PfMSP1p19 (rho = 0.78) and PF13-DBL1α1 (rho = 0.89), with a similar degree of concordance in all age groups. Antibody levels to both antigens were high but displayed a different age-associated pattern. Independent age-adjusted Poisson regression analysis showed a significant association with protection only for IgG responses to MSP1p19 (P <0.01 RR = 0.71 [0.53-0.93]) measured by ELISA. Conclusion The individual ELISA and duplex-MAGPIX assays provide a concordant evaluation of age-associated antibody responses to MSP1p19 and PF13-DBL1α1, irrespective of the formulation of antibody levels (values, ratios or ROC-adjusted figures) but do diverge with regard to the association of antibody levels with clinical protection in age-adjusted models. This may reflect incomplete overlap of the epitopes presented in the two formats. Further development for multiplex assessment of antibody responses to a larger panel of antigens with the robust and cost effective MAGPIX®-Luminex technology is warranted. Electronic supplementary material The online version of this article (doi:10.1186/1475-2875-13-410) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ronald Perraut
- Institut Pasteur de Dakar, Unité d'Immunologie, Dakar, Sénégal.
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20
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Plasmodium falciparum malaria in children aged 0-2 years: the role of foetal haemoglobin and maternal antibodies to two asexual malaria vaccine candidates (MSP3 and GLURP). PLoS One 2014; 9:e107965. [PMID: 25238160 PMCID: PMC4169582 DOI: 10.1371/journal.pone.0107965] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 08/07/2014] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Children below six months are reported to be less susceptible to clinical malaria. Maternally derived antibodies and foetal haemoglobin are important putative protective factors. We examined antibodies to Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate-rich protein (GLURP), in children in their first two years of life in Burkina Faso and their risk of malaria. METHODS A cohort of 140 infants aged between four and six weeks was recruited in a stable transmission area of south-western Burkina Faso and monitored for 24 months by active and passive surveillance. Malaria infections were detected by examining blood smears using light microscopy. Enzyme-linked immunosorbent assay was used to quantify total Immunoglobulin G to Plasmodium falciparum antigens MSP3 and two regions of GLURP (R0 and R2) on blood samples collected at baseline, three, six, nine, 12, 18 and 24 months. Foetal haemoglobin and variant haemoglobin fractions were measured at the baseline visit using high pressure liquid chromatography. RESULTS A total of 79.6% of children experienced one or more episodes of febrile malaria during monitoring. Antibody titres to MSP3 were prospectively associated with an increased risk of malaria while antibody responses to GLURP (R0 and R2) did not alter the risk. Antibody titres to MSP3 were higher among children in areas of high malaria risk. Foetal haemoglobin was associated with delayed first episode of febrile malaria and haemoglobin CC type was associated with reduced incidence of febrile malaria. CONCLUSIONS We did not find any evidence of association between titres of antibodies to MSP3, GLURP-R0 or GLURP-R2 as measured by enzyme-linked immunosorbent assay and early protection against malaria, although anti-MSP3 antibody titres may reflect increased exposure to malaria and therefore greater risk. Foetal haemoglobin was associated with protection against febrile malaria despite the study limitations and its role is therefore worthy further investigation.
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Arnott A, Wapling J, Mueller I, Ramsland PA, Siba PM, Reeder JC, Barry AE. Distinct patterns of diversity, population structure and evolution in the AMA1 genes of sympatric Plasmodium falciparum and Plasmodium vivax populations of Papua New Guinea from an area of similarly high transmission. Malar J 2014; 13:233. [PMID: 24930015 PMCID: PMC4085730 DOI: 10.1186/1475-2875-13-233] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/22/2014] [Indexed: 12/19/2022] Open
Abstract
Background As Plasmodium falciparum and Plasmodium vivax co-exist in most malaria-endemic regions outside sub-Saharan Africa, malaria control strategies in these areas must target both species in order to succeed. Population genetic analyses can predict the effectiveness of interventions including vaccines, by providing insight into patterns of diversity and evolution. The aim of this study was to investigate the population genetics of leading malaria vaccine candidate AMA1 in sympatric P. falciparum and P. vivax populations of Papua New Guinea (PNG), an area of similarly high prevalence (Pf = 22.3 to 38.8%, Pv = 15.3 to 31.8%). Methods A total of 72 Pfama1 and 102 Pvama1 sequences were collected from two distinct areas, Madang and Wosera, on the highly endemic PNG north coast. Results Despite a greater number of polymorphic sites in the AMA1 genes of P. falciparum (Madang = 52; Wosera = 56) compared to P. vivax (Madang = 36, Wosera = 34), the number of AMA1 haplotypes, haplotype diversity (Hd) and recombination (R) was far lower for P. falciparum (Madang = 12, Wosera = 20; Hd ≤0.92, R ≤45.8) than for P. vivax (Madang = 50, Wosera = 38; Hd = 0.99, R = ≤70.9). Balancing selection was detected only within domain I of AMA1 for P. vivax, and in both domains I and III for P. falciparum. Conclusions Higher diversity in the genes encoding P. vivax AMA1 than in P. falciparum AMA1 in this highly endemic area has important implications for development of AMA1-based vaccines in PNG and beyond. These results also suggest a smaller effective population size of P. falciparum compared to P. vivax, a finding that warrants further investigation. Differing patterns of selection on the AMA1 genes indicate that critical antigenic sites may differ between the species, highlighting the need for independent investigations of these two leading vaccine candidates.
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Affiliation(s)
| | | | | | | | | | | | - Alyssa E Barry
- Division of Infection and Immunity, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.
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22
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Ondigo BN, Hodges JS, Ireland KF, Magak NG, Lanar DE, Dutta S, Narum DL, Park GS, Ofulla AV, John CC. Estimation of recent and long-term malaria transmission in a population by antibody testing to multiple Plasmodium falciparum antigens. J Infect Dis 2014; 210:1123-32. [PMID: 24737801 DOI: 10.1093/infdis/jiu225] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Tools that estimate recent and long-term malaria transmission in a population would be highly useful for malaria elimination programs. METHODS The prevalence of antibodies to 11 Plasmodium falciparum antigens was assessed by cytometric bead assay or enzyme-linked immunosorbent assay in 1000 people in a highland area of Kenya over 14 months, during a period of interrupted malaria transmission. RESULTS Antibodies differed by antigen in acquisition with age: rapid (>80% antibody positive by age 20 years, 5 antigens), moderate (>40% positive by age 20 years, 3 antigens), or slow (<40% positive by age 20 years, 3 antigens). Antibody seroreversion rates in the 14 months between samples decreased with age rapidly (7 antigens), slowly (3 antigens), or remained high at all ages (schizont extract). Estimated antibody half-lives in individuals >10 years of age were long (40 to >80 years) for 5 antigens, moderate (5-20 years) for 3 antigens, and short (<1 year) for 3 antigens. CONCLUSIONS Antibodies to P. falciparum antigens in malaria-endemic areas vary by age, antigen, and time since last exposure to P. falciparum. Multiplex P. falciparum antibody testing could provide estimates of long-term and recent malaria transmission and potentially of a population's susceptibility to future clinical malaria.
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Affiliation(s)
- Bartholomew N Ondigo
- Department of Biomedical Science and Technology, Maseno University Center for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - James S Hodges
- Division of Biostatistics, School of Public Health, University of Minnesota
| | | | | | - David E Lanar
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - Sheetij Dutta
- Center for Global Health Research, Kenya Medical Research Institute, Kisumu
| | - David L Narum
- Malaria Vaccine Branch, Walter Reed Army Institute for Research, Silver Spring
| | - Gregory S Park
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, Maryland
| | - Ayub V Ofulla
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, Maryland
| | - Chandy C John
- Department of Pediatrics, University of Minnesota Medical School Center for Global Health Research, Kenya Medical Research Institute, Kisumu
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Medeiros MM, Fotoran WL, dalla Martha RC, Katsuragawa TH, Pereira da Silva LH, Wunderlich G. Natural antibody response to Plasmodium falciparum merozoite antigens MSP5, MSP9 and EBA175 is associated to clinical protection in the Brazilian Amazon. BMC Infect Dis 2013; 13:608. [PMID: 24373342 PMCID: PMC3880555 DOI: 10.1186/1471-2334-13-608] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 12/23/2013] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Antibodies have an essential role in the acquired immune response against blood stage P. falciparum infection. Although several antigens have been identified as important antibody targets, it is still elusive which antigens have to be recognized for clinical protection. Herein, we analyzed antibodies from plasmas from symptomatic or asymptomatic individuals living in the same geographic area in the Western Amazon, measuring their recognition of multiple merozoite antigens. METHODS Specific fragments of genes encoding merozoite proteins AMA1 and members of MSP and EBL families from circulating P. falciparum field isolates present in asymptomatic and symptomatic patients were amplified by PCR. After cloning and expression of different versions of the antigens as recombinant GST-fusion peptides, we tested the reactivity of patients' plasmas by ELISA and the presence of IgG subclasses in the most reactive plasmas. RESULTS 11 out of 24 recombinant antigens were recognized by plasmas from either symptomatic or asymptomatic infections. Antibodies to MSP9 (X2(DF=1) = 9.26/p = 0.0047) and MSP5 (X2(DF=1) = 8.29/p = 0.0069) were more prevalent in asymptomatic individuals whereas the opposite was observed for MSP1 block 2-MAD20 (X2(DF=1) = 6.41/p = 0.0206, Fisher's exact test). Plasmas from asymptomatic individuals reacted more intensely against MSP4 (U = 210.5, p < 0.03), MSP5 (U = 212, p < 0.004), MSP9 (U = 189.5, p < 0.002) and EBA175 (U = 197, p < 0.014, Mann-Whitney's U test). IgG1 and IgG3 were predominant for all antigens, but some patients also presented with IgG2 and IgG4. The recognition of MSP5 (OR = 0.112, IC95% = 0.021-0.585) and MSP9 (OR = 0.125, IC95% = 0.030-0.529, cross tab analysis) predicted 8.9 and 8 times less chances, respectively, to present symptoms. Higher antibody levels against MSP5 and EBA175 were associated by odds ratios of 9.4 (IC95% = 1.29-69.25) and 5.7 (IC95% = 1.12-29.62, logistic regression), respectively, with an asymptomatic status. CONCLUSIONS Merozoite antigens were targets of cytophilic antibodies and antibodies against MSP5, MSP9 and EBA175 were independently associated with decreased symptoms.
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Affiliation(s)
| | | | | | | | | | - Gerhard Wunderlich
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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Adu B, Jepsen MPG, Gerds TA, Kyei-Baafour E, Christiansen M, Dodoo D, Theisen M. Fc gamma receptor 3B (FCGR3B-c.233C>A-rs5030738) polymorphism modifies the protective effect of malaria specific antibodies in Ghanaian children. J Infect Dis 2013; 209:285-9. [PMID: 23935200 DOI: 10.1093/infdis/jit422] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Immunoglobulin G (IgG) cross-linking with Fc gamma receptor IIIB (FcγRIIIB) triggers neutrophil degranulation, releasing reactive oxygen species with high levels associated with protection against malaria. The FCGR3B-c.233C>A polymorphism thought to influence the interaction between IgG and FcγRIIIB was recently associated with malaria. We studied the statistical interaction between glutamate rich protein antibodies and FCGR3B-c.233C>A genotypes on risk of malaria in a cohort of Ghanaian children. The absolute risk of malaria decreased more rapidly with increasing antibody levels for 233AA/AC individuals compared with 233CC children. This genotype related effect modification may significantly influence malaria sero-epidemiological and vaccine trial studies.
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Affiliation(s)
- Bright Adu
- Department of Clinical Biochemistry and Immunology, Statens Serum Institut
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Detecting Foci of Malaria Transmission with School Surveys: A Pilot Study in the Gambia. PLoS One 2013; 8:e67108. [PMID: 23826205 PMCID: PMC3694932 DOI: 10.1371/journal.pone.0067108] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 05/16/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In areas of declining malaria transmission such as in The Gambia, the identification of malaria infected individuals becomes increasingly harder. School surveys may be used to identify foci of malaria transmission in the community. METHODS The survey was carried out in May-June 2011, before the beginning of the malaria transmission season. Thirty two schools in the Upper River Region of The Gambia were selected with probability proportional to size; in each school approximately 100 children were randomly chosen for inclusion in the study. Each child had a finger prick blood sample collected for the determination of antimalarial antibodies by ELISA, malaria infection by microscopy and PCR, and for haemoglobin measurement. In addition, a simple questionnaire on socio-demographic variables and the use of insecticide-treated bed nets was completed. The cut-off for positivity for antimalarial antibodies was obtained using finite mixture models. The clustered nature of the data was taken into account in the analyses. RESULTS A total of 3,277 children were included in the survey. The mean age was 10 years (SD = 2.7) [range 4-21], with males and females evenly distributed. The prevalence of malaria infection as determined by PCR was 13.6% (426/3124) [95% CI = 12.2-16.3] with marked variation between schools (range 3-25%, p<0.001), while the seroprevalence was 7.8% (234/2994) [95%CI = 6.4-9.8] for MSP119, 11.6% (364/2997) [95%CI = 9.4-14.5] for MSP2, and 20.0% (593/2973) [95% CI = 16.5-23.2) for AMA1. The prevalence of all the three antimalarial antibodies positive was 2.7% (79/2920). CONCLUSIONS This survey shows that malaria prevalence and seroprevalence before the transmission season were highly heterogeneous.
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How Should Antibodies against P. falciparum Merozoite Antigens Be Measured? J Trop Med 2013; 2013:493834. [PMID: 23690791 PMCID: PMC3652195 DOI: 10.1155/2013/493834] [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: 11/14/2012] [Revised: 04/01/2013] [Accepted: 04/02/2013] [Indexed: 11/18/2022] Open
Abstract
Immunity against malaria develops slowly and only after repeated exposure to the parasite. Many of those that die of the disease are children under five years of age. Antibodies are an important part of immunity, but which antibodies that are protective and how these should be measured are still unclear. We discuss the pros and cons of ELISA, invasion inhibition assays/ADCI, and measurement of affinity of antibodies and what can be done to improve these assays, thereby increasing the knowledge about the immune status of an individual, and to perform better evaluation of vaccine trials.
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Oduro AR, Wak G, Azongo D, Debpuur C, Wontuo P, Kondayire F, Welaga P, Bawah A, Nazzar A, Williams J, Hodgson A, Binka F. Profile of the Navrongo Health and Demographic Surveillance System. Int J Epidemiol 2013; 41:968-76. [PMID: 22933645 DOI: 10.1093/ije/dys111] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Located in the Kassena-Nankana districts of northern Ghana, the Navrongo health and demographic surveillance system (NHDSS) was established in 1992 by the Navrongo health research centre (NHRC). The NHRC is one of three research centres of the Ghana health service. The activities and potential of the NHDSS for collaborative research are described. The NHDSS monitors health and demographic dynamics of the two Kassena-Nankana districts of northern Ghana and facilitates evaluation of the morbidity and mortality impact of health and social interventions. The total population currently under surveillance is 152 000 residing in 32 000 households. Events monitored routinely include pregnancies, births, morbidity, deaths, migration, marriages and vaccination coverage. Data updates are done every 4 months by trained fieldworkers. The NHRC also undertakes biomedical and socio-economic studies. Additional features of the NHDSS include the community key informant system where trained volunteers routinely report key events, such as births and deaths as they occur in their locality and the verbal autopsy (VA) system for determining the probable causes of deaths that occur at the community level. Data from the NHDSS are shared with funders and collaborators and partners in the INDEPTH Network. The Director of the NHDSS is the contact person for potential collaboration with the NHDSS and the use of its data.
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Kynast-Wolf G, Wakilzadeh W, Coulibaly B, Schnitzler P, Traoré C, Becher H, Müller O. ITN protection, MSP1 antibody levels and malaria episodes in young children of rural Burkina Faso. Acta Trop 2012; 123:117-22. [PMID: 22569564 DOI: 10.1016/j.actatropica.2012.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 03/29/2012] [Accepted: 04/22/2012] [Indexed: 10/28/2022]
Abstract
Malaria blood-stage vaccines are in an early phase of clinical development with MSP1 being a major antigen candidate. There are limited data on the protective efficacy of antibodies against subunits of MSP1 in the malaria endemic areas of sub-Saharan Africa. This prospective cohort study was nested into a large insecticide-treated mosquito net (ITN) trial during which neonates were individually randomised to ITN protection from birth vs. protection from month six onwards in rural Burkina Faso. A sub sample of 120 children from three villages was followed for 10 months with six measurements of MSP1(42) antibodies (ELISA based on recombinant 42kDa fragment) and daily assessment of malaria episodes. Time to the next malaria episode was determined in relation to MSP1(42) antibody titres. MSP1(42) antibody titres were dependent on age, season, ITN-group, number of previous malaria episodes and parasitaemia. There were no significant differences in time until the next malaria episode in children with low compared to children with high MSP1(42) antibody titres at any point in time (101 vs. 97 days in May, p=0.6; 58 vs. 84 days in September, p=0.3; 144 vs. 161 days in March, p=0.5). The findings of this study support the short-lived nature of the humoral immune response in infants of malaria endemic areas. The study provides no evidence for antibodies against a subunit of MSP1 being protective against new malaria episodes in infants.
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Affiliation(s)
- Gisela Kynast-Wolf
- Institute of Public Health, Ruprecht-Karls-University Heidelberg, Germany.
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29
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Kusi KA, Dodoo D, Bosomprah S, van der Eijk M, Faber BW, Kocken CHM, Remarque EJ. Measurement of the plasma levels of antibodies against the polymorphic vaccine candidate apical membrane antigen 1 in a malaria-exposed population. BMC Infect Dis 2012; 12:32. [PMID: 22299616 PMCID: PMC3317819 DOI: 10.1186/1471-2334-12-32] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 02/02/2012] [Indexed: 11/24/2022] Open
Abstract
Background Establishing antibody correlates of protection against malaria in human field studies and clinical trials requires, amongst others, an accurate estimation of antibody levels. For polymorphic antigens such as apical membrane antigen 1 (AMA1), this may be confounded by the occurrence of a large number of allelic variants in nature. Methods To test this hypothesis, plasma antibody levels in an age-stratified cohort of naturally exposed children from a malaria-endemic area in Southern Ghana were determined by indirect ELISA. Titres against four single PfAMA1 alleles were compared with those against three different allele mixtures presumed to have a wider repertoire of epitope specificities. Associations of antibody levels with the incidence of clinical malaria as well as with previous exposure to parasites were also examined. Results Antibody titres against PfAMA1 alleles generally increased with age/exposure while antibody specificity for PfAMA1 variants decreased, implying that younger children (≤ 5 years) elicit a more strain-specific antibody response compared to older children. Antibody titre measurements against the FVO and 3D7 AMA1 alleles gave the best titre estimates as these varied least in pair-wise comparisons with titres against all PfAMA1 allele mixtures. There was no association between antibody levels against any capture antigen and either clinical malaria incidence or parasite density. Conclusions The current data shows that levels of naturally acquired antigen-specific antibodies, especially in infants and young children, are dependent on the antigenic allele used for measurement. This may be relevant to the interpretation of antibody titre data from measurements against single PfAMA1 alleles, especially in studies involving infants and young children who have experienced fewer infections.
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Affiliation(s)
- Kwadwo A Kusi
- Department of Parasitology, Biomedical Primate Research Centre, Postbox 3306, 2280, GH Rijswijk, The Netherlands.
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Fontaine A, Diouf I, Bakkali N, Missé D, Pagès F, Fusai T, Rogier C, Almeras L. Implication of haematophagous arthropod salivary proteins in host-vector interactions. Parasit Vectors 2011; 4:187. [PMID: 21951834 PMCID: PMC3197560 DOI: 10.1186/1756-3305-4-187] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 09/28/2011] [Indexed: 01/25/2023] Open
Abstract
The saliva of haematophagous arthropods contains an array of anti-haemostatic, anti-inflammatory and immunomodulatory molecules that contribute to the success of the blood meal. The saliva of haematophagous arthropods is also involved in the transmission and the establishment of pathogens in the host and in allergic responses. This survey provides a comprehensive overview of the pharmacological activity and immunogenic properties of the main salivary proteins characterised in various haematophagous arthropod species. The potential biological and epidemiological applications of these immunogenic salivary molecules will be discussed with an emphasis on their use as biomarkers of exposure to haematophagous arthropod bites or vaccine candidates that are liable to improve host protection against vector-borne diseases.
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Affiliation(s)
- Albin Fontaine
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Ibrahima Diouf
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Nawal Bakkali
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Dorothée Missé
- Laboratoire de Génétique et Evolution des Maladies infectieuses, UMR 2724 CNRS/IRD, Montpellier, France
| | - Frédéric Pagès
- Unité d'Entomologie Médicale, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Thierry Fusai
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
| | - Christophe Rogier
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
- Institut Pasteur de Madagascar, B.P. 1274, Ambohitrakely, 101 Antananarivo, Madagascar
| | - Lionel Almeras
- Unité de Parasitologie - UMR6236 - IFR48, Antenne Marseille de l'Institut de Recherche Biomédicale des Armées (IRBA), Le Pharo, BP 60109, 13 262 Marseille Cedex 07, France
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Dodoo D, Hollingdale MR, Anum D, Koram KA, Gyan B, Akanmori BD, Ocran J, Adu-Amankwah S, Geneshan H, Abot E, Legano J, Banania G, Sayo R, Brambilla D, Kumar S, Doolan DL, Rogers WO, Epstein J, Richie TL, Sedegah M. Measuring naturally acquired immune responses to candidate malaria vaccine antigens in Ghanaian adults. Malar J 2011; 10:168. [PMID: 21689436 PMCID: PMC3132199 DOI: 10.1186/1475-2875-10-168] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/20/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To prepare field sites for malaria vaccine trials, it is important to determine baseline antibody and T cell responses to candidate malaria vaccine antigens. Assessing T cell responses is especially challenging, given genetic restriction, low responses observed in endemic areas, their variability over time, potential suppression by parasitaemia and the intrinsic variability of the assays. METHODS In Part A of this study, antibody titres were measured in adults from urban and rural communities in Ghana to recombinant Plasmodium falciparum CSP, SSP2/TRAP, LSA1, EXP1, MSP1, MSP3 and EBA175 by ELISA, and to sporozoites and infected erythrocytes by IFA. Positive ELISA responses were determined using two methods. T cell responses to defined CD8 or CD4 T cell epitopes from CSP, SSP2/TRAP, LSA1 and EXP1 were measured by ex vivo IFN-γ ELISpot assays using HLA-matched Class I- and DR-restricted synthetic peptides. In Part B, the reproducibility of the ELISpot assay to CSP and AMA1 was measured by repeating assays of individual samples using peptide pools and low, medium or high stringency criteria for defining positive responses, and by comparing samples collected two weeks apart. RESULTS In Part A, positive antibody responses varied widely from 17%-100%, according to the antigen and statistical method, with blood stage antigens showing more frequent and higher magnitude responses. ELISA titres were higher in rural subjects, while IFA titres and the frequencies and magnitudes of ex vivo ELISpot activities were similar in both communities. DR-restricted peptides showed stronger responses than Class I-restricted peptides. In Part B, the most stringent statistical criteria gave the fewest, and the least stringent the most positive responses, with reproducibility slightly higher using the least stringent method when assays were repeated. Results varied significantly between the two-week time-points for many participants. CONCLUSIONS All participants were positive for at least one malaria protein by ELISA, with results dependent on the criteria for positivity. Likewise, ELISpot responses varied among participants, but were relatively reproducible by the three methods tested, especially the least stringent, when assays were repeated. However, results often differed between samples taken two weeks apart, indicating significant biological variability over short intervals.
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Affiliation(s)
- Daniel Dodoo
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana
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