The extent to which human group 1 CD1-restricted (CD1a-, CD1b-, and CD1c-restricted) T cells behave as naive or memory T cells in the periphery, remains poorly understood, owing mainly to technical challenges in directly addressing these questions in humans and limited tractable infection models that express CD1a, CD1b, and CD1c (which are lacking in mice) (32). The gene discussed is CD1A; the disease is infection.