Figure 1.

Three suggested models of T_SCM cell differentiation. (A) The “linear model” stipulates that a T cell loses its memory strength and develops remarkable effector capabilities during differentiation based on the T-cell receptor (TCR) potential signal and extent and persistence of antigenic stimulation on the cells. (B) The “circular model” claims that effector T cells should emerge before memory T-cell dedifferentiation. (C) The “asymmetric division model” proposes that the formation of memory and effector T cells is predetermined from the first division via asymmetric distribution of key modulators between two daughter cells.