Concerning leishmaniasis, we recently reported that mice infected with L. amazonensis presented high expression of PD-1 in CD4+ and CD8+ T cells, and PD-L1 in dendritic cells, and that treatment with anti-PD-1 or anti-PD-L1 antibodies reduced the parasite load and increased IFN-gamma production by CD4+ and CD8+ T cells, thus, reversing cell suppression (28). The gene discussed is CD4; the disease is leishmaniasis.