Tr. Malek et al., Broad programming by IL-2 receptor signaling for extended growth to multiple cytokines and functional maturation of antigen-activated T cells, J IMMUNOL, 166(3), 2001, pp. 1675-1683
Coincident production of IL-2 and induction of high-affinity IL-2R upon TCR
engagement has precluded a clear distinction for the biological outcome of
signaling through TCR/costimulatory molecules vs the IL-2R, Using a novel
transgenic mouse on the IL-2R beta (-/-) genetic background, this study has
separated the relative outcome of signaling through the TCR and IL-2R, We
show that stimulation through the TCR and CD28 or CD40 ligand directly lead
s to T cell activation and several rounds of proliferation in an IL-2-indep
endent fashion. However, this stimulation is insufficient for extended T ce
ll growth to multiple cytokines or differentiation into CTL or IFN-gamma -s
ecreting effector T cells. IL-2 is required for these functions in part by
regulation of cyclin D3 and granzyme B, Somewhat less efficiently, IL-4 sti
mulation of these transgenic T cells redundantly rescued many of these acti
vities, These data demonstrate a fundamental requirement for IL-2 and perha
ps other common gamma -chain-dependent cytokines to promote selective gene
expression by Ag-activated T cells for their subsequent growth and differen
tiation into effector T lymphocytes.