McLane et al. (2021) have also demonstrated that blocking PD-1 signaling in exhausted cells increases nuclear T-bet and restores full repression of Pdcd1. In Crohn’s disease, T-bet may be responsible for the development and persistence of the inflammation as its overexpression seems to interfere with PD-1/PDL-1 mediated suppression of CD4+ T cell survival [177]. Here, PDCD1 is linked to Crohn disease.