Malnutrition disrupts adaptive immunity during visceral leishmaniasis by enhancing IL-10 production.

Malnutrition contributes to the development of VL. Despite the advances regarding this association, how malnutrition affects the adaptive immune mechanisms in VL is still unclear. We found that malnutrition disrupts the ability to control parasite replication in the spleen and liver in VL due to defective IFN-γ-mediated immunity, reduced hepatic granuloma formation, and enhanced IL-10 production. Blocking IL-10R signaling restored the protective mechanisms to control parasite replication in the malnourished mice without interfering with the undernutrition state. Thus, we demonstrate that malnutrition disrupts the adaptive immunity against VL due to an aberrant IL-10 production. Understanding the association between malnutrition and VL will provide insights into therapeutic approaches.