Granzyme A-expressing Terminal Effector T Cells Dedifferentiate into Long-lived Memory T Cells

However, the differentiation path of memory T cells is not completely understood. Early bulk cell population-based studies support a linear model, in which effector T cells lose the effector program and dedifferentiate into memory T cells.

Recent research supports a bifurcation model, where T cells choose one of the two paths, either the effector or the memory path, at an early stage of T cell responses. Terminal effector T cells lose the capacity to become memory T cells. Here, we first demonstrate that the expression of granzyme A is largely distinct from that of granzyme B and marks terminal cytotoxic effector CD8+ T cells with reduced polyfunctionality.