Pregnancy-associated malaria (PAM) can lead to severe complications for both mother and child. Recent studies have investigated a broader spectrum of circulating and/or placental cytokines aiming to find potential biomarkers for inflammatory placental malaria and or possible links with poor PAM outcomes. In this context, the STOPPAM consortium conducted 2 longitudinal cohort studies in pregnant women in Benin in order to evaluate the immunopathological consequences of infections with P. falciparum during pregnancy.
Here we made use of a large sub-group drawn from the STOPPAM cohort of 1037 pregnant women enrolled at ≤ 24weeks of pregnancy and followed at each antenatal visit until delivery. Thus, 400 Beninese women were selected according to the documented presence/absence of infection with P. falciparum. And we quantified 5 plasma cytokines level at inclusion, antenatal visit and delivery. The amounts of IL-4, IL-5, IL-10, IFN-γ and IL-12 were determined by multiplex using Cytometric Bead Array (CBA) enhanced sensitivity technology.
Between subgroups of women harboring P. falciparum infection, maternal anemia, preterm births, or low birth weight for gestational age, cytokine responses were compared for everyone at the three times point using the Kruskal-Wallis test. We also compared women not infected during pregnancy with those infected only once during pregnancy (but no not at delivery), and those infected at least twice during pregnancy.
Overall the cytokines detected, the levels of the anti-inflammatory cytokine IL-10 was higher in the plasma of women with P. falciparum infection than uninfected. According to the number of infection, the amounts of Th1 and Th2-type cytokines decrease progressively over the course of pregnancy as the number of infection increased. When comparing the level cytokines at inclusion, antenatal visit and at delivery some trends for decreasing of all the cytokines were observed with significant association for IL-10. Further multivariate analyses of cytokine levels are ongoing.