Effects of Pregnancy-associated Malaria on T Cell Cytokines in Cameroonian Women

Abstract

Although Th17 cells subsets improve immunity against extra and intracellular pathogens, and in modulating Th1 and other immune responses, its role on pregnancy-associated malaria (PAM) is unknown. This study aims to investigate the effects of PAM on Th1 (IFN-γ, TNF-α), IL-10 family (IL-10, IL-19, IL-22), Th17 (IL-17A, IL-23) cytokines and on CXCL-10 chemokine profiles in pregnant women. Between 2010 and 2011, venous blood specimens from 107 volunteer pregnant Cameroonian women was used to determine parasitaemia microscopically and haemoglobin levels using HemoCue analyzer. Plasma levels of the biomarkers were determined by ELISA. Parasitaemia was higher in women with low haemoglobin levels, parity and mother's age. IL-10 and CXCL-10 plasma levels were higher in the malaria infected and in anaemic women while IFN-γ and IL-17A levels were higher in malaria non-infected and in non-anaemic women. Parasitaemia correlated positively with IL-10 and CXCL-10 levels but inversely with IFN-γ and IL-17A. Haemoglobin levels were higher in women with low IL-10 and CXCL-10 levels, and in group with high IFN-γ, IL-17A and IL-23 levels. Only IL-10 levels associated negatively with parity. Positive correlations were observed between Th17 (IL-17A) and Th1 (IFN-γ, TNF-α), IL-10 family (IL-19 and IL-22) and Th17 (IL-23) cytokines. Multivariate analysis showed association between: mother's age and IFN-γ levels, parasitaemia and IL-10 and CXCL-10 levels and haemoglobin levels, gestational age and IL-17A levels. In conclusion, during PAM, CXCL-10 and IL-10 responses are implicated in the pathogenesis while Th17 and Th1 immune responses, via IL-17A and IFN-γ might play protective roles.