Both CD1d antigen presentation and interleukin-12 are required to activate natural killer T cells during Trypanosoma cruzi infection.

Mechanisms of natural killer T (NKT)-cell activation remain unclear. Here, we report that during Trypanosoma cruzi infection, interleukin-12 (IL-12) deficiency or anti-CD1d antibody treatment prevents normal activation. The required IL-12 arises independently of MyD88. The data support a model of normal NKT-cell activation that requires IL-12 and TCR stimulation.