TY - JOUR
T1 - Human saliva as a source of anti-malarial antibodies to examine population exposure to Plasmodium falciparum
AU - Estévez, Patricia Tabernero
AU - Satoguina, Judith
AU - Nwakanma, Davis C.
AU - West, Sheila
AU - Conway, David J.
AU - Drakeley, Chris J.
N1 - Funding Information:
We wish to thank the participants and staff of the KTP & MRC (UK) The Gambia. We thank Ed Remarque and Bart Faber for the provision of the AMA-1 protein, Tedson Lukindo for help in the laboratory in Moshi, Eniyou Oriero in Fajara and Patrick Corran and Jackie Cook for help and advice in London. The Gambia sampling and assays were supported by a project grant to DCN from PATH-Malaria Vaccine Initiative and Tanzania studies through a grant to from the Wellcome Trust to CD (078925) and a Grant from Bill & Melinda Gates Foundation to SW.
PY - 2011
Y1 - 2011
N2 - Background: Antibody responses to malaria antigens reflect exposure to parasites, and seroprevalence correlates with malaria transmission intensity. Antibodies are routinely measured in sera or on dried blood spots but a non-invasive method would provide extra utility in sampling general populations. Saliva is already in use in the detection of plasma-derived IgM and IgG to viral infections. In this study, antibodies to Plasmodium falciparum merozoite antigens were compared between blood and saliva samples from the same individuals in unlinked surveys conducted in Tanzania and The Gambia. Methods. In Tanzania, 53 individuals provided paired fingerprick blood and saliva sample using two commercially available sampling devices. In the Gambia, archived plasma and saliva samples collected from 200 children in the Farafenni area in a cross-sectional survey were analyzed. IgG antibodies against P. falciparum antigens, Merozoite Surface Protein-1 (MSP-119) and Apical membrane Antigen (AMA-1) were measured by ELISA in paired saliva and blood samples from both sites. Antibody levels were compared as continuous optical density (OD) values and by sero-positivity. Results: Significant correlations between saliva and plasma antibody levels were seen in Tanzania for both antigens, AMA-1(r 2 range 0.93 to 0.89, p < 0.001) and MSP-119(r 2 range 0.93 to 0.75, p < 0.001), with a weaker correlation for results from The Gambia (r2range 0.64 to 0.63, p < 0.01). When assessed as seropositivity and compared with plasma, sensitivity and specificity were good with saliva antibody levels to both AMA-1 and MSP-1 19(sensitivity range 64-77% and specificity range 91-100% & 47-67% and 90-97% respectively) over the different sample sets. Conclusions: These data demonstrate anti-malarial antibodies can be detected in saliva and correlate strongly with levels in plasma. This non-invasive relatively simple collection method will be potentially useful for general population surveys, and particularly in migratory populations or those with infrequent contact with health services or opposed to blood withdrawal. Further studies will be needed to optimize collection methods, standardize volumes and content and develop controls.
AB - Background: Antibody responses to malaria antigens reflect exposure to parasites, and seroprevalence correlates with malaria transmission intensity. Antibodies are routinely measured in sera or on dried blood spots but a non-invasive method would provide extra utility in sampling general populations. Saliva is already in use in the detection of plasma-derived IgM and IgG to viral infections. In this study, antibodies to Plasmodium falciparum merozoite antigens were compared between blood and saliva samples from the same individuals in unlinked surveys conducted in Tanzania and The Gambia. Methods. In Tanzania, 53 individuals provided paired fingerprick blood and saliva sample using two commercially available sampling devices. In the Gambia, archived plasma and saliva samples collected from 200 children in the Farafenni area in a cross-sectional survey were analyzed. IgG antibodies against P. falciparum antigens, Merozoite Surface Protein-1 (MSP-119) and Apical membrane Antigen (AMA-1) were measured by ELISA in paired saliva and blood samples from both sites. Antibody levels were compared as continuous optical density (OD) values and by sero-positivity. Results: Significant correlations between saliva and plasma antibody levels were seen in Tanzania for both antigens, AMA-1(r 2 range 0.93 to 0.89, p < 0.001) and MSP-119(r 2 range 0.93 to 0.75, p < 0.001), with a weaker correlation for results from The Gambia (r2range 0.64 to 0.63, p < 0.01). When assessed as seropositivity and compared with plasma, sensitivity and specificity were good with saliva antibody levels to both AMA-1 and MSP-1 19(sensitivity range 64-77% and specificity range 91-100% & 47-67% and 90-97% respectively) over the different sample sets. Conclusions: These data demonstrate anti-malarial antibodies can be detected in saliva and correlate strongly with levels in plasma. This non-invasive relatively simple collection method will be potentially useful for general population surveys, and particularly in migratory populations or those with infrequent contact with health services or opposed to blood withdrawal. Further studies will be needed to optimize collection methods, standardize volumes and content and develop controls.
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U2 - 10.1186/1475-2875-10-104
DO - 10.1186/1475-2875-10-104
M3 - Article
C2 - 21527045
AN - SCOPUS:79958835950
SN - 1475-2875
VL - 10
JO - Malaria journal
JF - Malaria journal
M1 - 104
ER -