HLA-G expression during hookworm infection in pregnant women.


MERIT, Institut de Recherche pour le Développement (IRD), Université Sorbonne Paris Cité, Université Paris Descartes, France. Electronic address: [Email]


BACKGROUND : HLA-G plays a key role on immune tolerance. Pathogens can induce soluble HLA-G (sHLA-G) production to down-regulate the host immune response, creating a tolerogenic environment favorable for their dissemination. To our knowledge, no study has yet been conducted to assess the relationship between sHLA-G and geohelminth infections.
METHODS : The study was conducted in Allada, Southeastern Benin, from 2011-2014. The study population encompassed 400 pregnant women, included before the end of the 28th week of gestation and followed-up until delivery. At two antenatal care visits and at delivery, stool and blood samples were collected. Helminths were diagnosed by means of the Kato-Katz concentration technique. We used quantile regression to analyze the association between helminth infections and sHLA-G levels during pregnancy.
RESULTS : sHLA-G levels gradually increased during pregnancy and reached maximal levels at delivery. Prevalence of helminth infections was low, with a majority of hookworm infections. We found significantly more hookworm-infected women above the 80th quantile (Q80) of the distribution of the mean sHLA-G level (p < 0.03, multivariate quantile regression). Considering only women above the Q80 percentile, the mean sHLA-G level was significantly higher in hookworm-infected compared to uninfected women (p = 0.04).
CONCLUSIONS : High levels of sHLA-G were associated with hookworm infection in pregnant women. This result is consistent with the potential involvement of sHLA-G in immune tolerance induced by helminths during pregnancy.


HLA-G,Helminth,Hookworm,Immune tolerance,Neglected tropical diseases,Pregnant women,