Role of Plasmodium Falciparuminfection In Transplacental Transfer Of Antibodies.

Abstract

Even with several therapeutic interventions and a few vaccination strategies, Malaria still killed over 380,000 people in 2019alone,in Sub Saharan African Countries. One major cause is impaired transfer of antibodies from mother to child to aid passive immunity early in life. Naturally acquired antibodies against individual antigens or panels of antigens in hyper-endemic regions have been associated with protection against clinical disease and severe disease in newborns. This study aimed at evaluating the impairment of antibody transfer against MSP-1 and AMA-1 by P. falciparum infection during pregnancy. 298 pairs of archived cord-maternal plasma sample were analyzed for Specific IgG antibodies against P. falciparum antigens, (MSP)-1 and (AMA)-1using enzyme linked immunosorbent assay. Statistical analyses were performed using STATA version 14.0.Cord-to-maternal ratios(CMR)were calculated for each sample as a measure of transplacental antibody transfer. Chi-square test was performed to determine association between P. falciparum infection and transplacental antibody transfer impairment. The mean MSP-1 CMR was 8.32 with IQR of 0.39, 1.44and the mean AMA-1 CMR was 1.67 with IQR of 0.51, 1.33. The proportion of mothers with transplacental transfer impairment were 62.42% and 63.09% forMSP-1 and AMA-1 antibodies respectively. We found no statistically significant association between transplacental antibody transfer impairment (CMR below 1.0), and P. falciparum infection for both antibodies (Pearson Chi-Square = 2.557, p= 0.110andPearson Chi-Square = 0.233,P-Value = 0.629for MSP-1 and AMA-1 antibodies respectively although there was a major limitation of the small sample size to this finding. P. falciparum infection during pregnancy may not be associated with impairment of transplacental transfer of anti malarial antibodies although another study involving a larger sample size of mothers infected with P. falciparum is required to better understand this relationship and other confounding factors.