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Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria

BACKGROUND: Pregnant women residing in malaria endemic areas are highly susceptible to Plasmodium falciparum malaria, particularly during their first pregnancy, resulting in low birth weight babies and maternal anaemia. This susceptibility is associated with placental sequestration of parasitised re...

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Autores principales: Ataíde, Ricardo, Hasang, Wina, Wilson, Danny W., Beeson, James G., Mwapasa, Victor, Molyneux, Malcolm E., Meshnick, Steven R., Rogerson, Stephen J.
Formato: Texto
Lenguaje:English
Publicado: Public Library of Science 2010
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2876038/
https://www.ncbi.nlm.nih.gov/pubmed/20520838
http://dx.doi.org/10.1371/journal.pone.0010807
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author Ataíde, Ricardo
Hasang, Wina
Wilson, Danny W.
Beeson, James G.
Mwapasa, Victor
Molyneux, Malcolm E.
Meshnick, Steven R.
Rogerson, Stephen J.
author_facet Ataíde, Ricardo
Hasang, Wina
Wilson, Danny W.
Beeson, James G.
Mwapasa, Victor
Molyneux, Malcolm E.
Meshnick, Steven R.
Rogerson, Stephen J.
author_sort Ataíde, Ricardo
collection PubMed
description BACKGROUND: Pregnant women residing in malaria endemic areas are highly susceptible to Plasmodium falciparum malaria, particularly during their first pregnancy, resulting in low birth weight babies and maternal anaemia. This susceptibility is associated with placental sequestration of parasitised red blood cells expressing pregnancy-specific variant surface antigens. Acquisition of antibodies against these variant surface antigens may protect women and their offspring. Functions of such antibodies may include prevention of placental sequestration or opsonisation of parasitised cells for phagocytic clearance. METHODOLOGY/FINDINGS: Here we report the development and optimisation of a new high-throughput flow cytometry-based phagocytosis assay using undifferentiated Thp-1 cells to quantitate the amount of opsonizing antibody in patient sera, and apply this assay to measure the impact of HIV on the levels of antibodies to a pregnancy malaria-associated parasite line in a cohort of Malawian primigravid women. The assay showed high reproducibility, with inter-experimental correlation of r(2) = 0.99. In primigravid women, concurrent malaria infection was associated with significantly increased antibodies, whereas HIV decreased the ability to acquire opsonising antibodies (Mann-Whitney ranksum: p = 0.013). This decrease was correlated with HIV-induced immunosuppression, with women with less than 350×10(6) CD4+ T- cells/L having less opsonising antibodies (coef: −11.95,P = 0.002). Levels of antibodies were not associated with protection from low birth weight or anaemia. CONCLUSIONS/SIGNIFICANCE: This flow cytometry-based phagocytosis assay proved to be efficient and accurate for the measurement of Fc-receptor mediated phagocytosis-inducing antibodies in large cohorts. HIV was found to affect mainly the acquisition of antibodies to pregnancy-specific malaria in primigravidae. Further studies of the relationship between opsonising antibodies to malaria in pregnancy and HIV are indicated.
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spelling pubmed-28760382010-06-02 Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria Ataíde, Ricardo Hasang, Wina Wilson, Danny W. Beeson, James G. Mwapasa, Victor Molyneux, Malcolm E. Meshnick, Steven R. Rogerson, Stephen J. PLoS One Research Article BACKGROUND: Pregnant women residing in malaria endemic areas are highly susceptible to Plasmodium falciparum malaria, particularly during their first pregnancy, resulting in low birth weight babies and maternal anaemia. This susceptibility is associated with placental sequestration of parasitised red blood cells expressing pregnancy-specific variant surface antigens. Acquisition of antibodies against these variant surface antigens may protect women and their offspring. Functions of such antibodies may include prevention of placental sequestration or opsonisation of parasitised cells for phagocytic clearance. METHODOLOGY/FINDINGS: Here we report the development and optimisation of a new high-throughput flow cytometry-based phagocytosis assay using undifferentiated Thp-1 cells to quantitate the amount of opsonizing antibody in patient sera, and apply this assay to measure the impact of HIV on the levels of antibodies to a pregnancy malaria-associated parasite line in a cohort of Malawian primigravid women. The assay showed high reproducibility, with inter-experimental correlation of r(2) = 0.99. In primigravid women, concurrent malaria infection was associated with significantly increased antibodies, whereas HIV decreased the ability to acquire opsonising antibodies (Mann-Whitney ranksum: p = 0.013). This decrease was correlated with HIV-induced immunosuppression, with women with less than 350×10(6) CD4+ T- cells/L having less opsonising antibodies (coef: −11.95,P = 0.002). Levels of antibodies were not associated with protection from low birth weight or anaemia. CONCLUSIONS/SIGNIFICANCE: This flow cytometry-based phagocytosis assay proved to be efficient and accurate for the measurement of Fc-receptor mediated phagocytosis-inducing antibodies in large cohorts. HIV was found to affect mainly the acquisition of antibodies to pregnancy-specific malaria in primigravidae. Further studies of the relationship between opsonising antibodies to malaria in pregnancy and HIV are indicated. Public Library of Science 2010-05-25 /pmc/articles/PMC2876038/ /pubmed/20520838 http://dx.doi.org/10.1371/journal.pone.0010807 Text en Ataíde et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Ataíde, Ricardo
Hasang, Wina
Wilson, Danny W.
Beeson, James G.
Mwapasa, Victor
Molyneux, Malcolm E.
Meshnick, Steven R.
Rogerson, Stephen J.
Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title_full Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title_fullStr Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title_full_unstemmed Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title_short Using an Improved Phagocytosis Assay to Evaluate the Effect of HIV on Specific Antibodies to Pregnancy-Associated Malaria
title_sort using an improved phagocytosis assay to evaluate the effect of hiv on specific antibodies to pregnancy-associated malaria
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2876038/
https://www.ncbi.nlm.nih.gov/pubmed/20520838
http://dx.doi.org/10.1371/journal.pone.0010807
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