Co‐stimulation with LFA‐1 triggers apoptosis in γδ T cells on T cell receptor engagement

Abstract

Stimulation of T cells through the T cell receptor (TcR) initiate activation pathways, and paradoxically can also result in activation‐induced cell death. Many factors influence a stimulated cell's decision to manifest one or the other. Here we show that co‐stimulation with LFA‐1 plays a key role in the choice between the two fates, differentiating between αβ and γδ T cells. Peripheral γδ T cells but not αβ T cells undergo apoptosis upon co‐cross‐linking of TcR and LFA‐1 in MRL lpr/lpr mice as well as +/+ mice. Our results suggest that apoptosis of γδ T cells is inducible by combined stimuli independent of the Fas‐mediated pathway.