The correlation between B cells and a poor prognosis in leishmaniasis was also evidenced by the work of Omachi et al., demonstrating that animals deficient in B cell activating factor (BAFF) can suppress the splenomegaly characteristic of the disease in the experimental model of VL with L. donovani, but not hepatomegaly (Omachi et al., 2017). The gene discussed is TNFSF13B; the disease is leishmaniasis.