The ability of cytotoxic T lymphocytes (CTLs) to kill target cells is essential for immune system function and recent cancer therapies. Basu et al. show that CTLs induce cell death in part by tugging on the target cell. Stimulating CTLs caused increased force generation that was associated with increased formation of pores in target cells, which result from release of the perforin protein from CTLs. Enhanced pore formation and the resultant lysis of target cells were diminished if force generation was limited by growing cells on soft hydrogels. Local activation of pore formation in this manner may help protect neighboring cells from cytolytic secretions.
Cell 10.1016/j.cell.2016.01.021(2016).