T. Brocker et K. Karjalainen, SIGNALS THROUGH T-CELL RECEPTOR-XI CHAIN ALONE ARE INSUFFICIENT TO PRIME RESTING T-LYMPHOCYTES, The Journal of experimental medicine, 181(5), 1995, pp. 1653-1659
Activation studies performed with transfected T cell hybridomas and tu
mors revealed that chimeric molecules containing the CD3 epsilon or ze
ta chain intracytoplasmic portions can induce the complete effector fu
nctions normally seen only when the complete T cell receptor (TCR)/CD3
complexes of T lymphocytes are triggered. Therefore, the zeta chain,
with its three antigen recognition activation motives, is thought to c
onnect the antigen-binding Ti chains with the intracellular signaling
machinery of the T cell. Here we demonstrate that the cytoplasmic port
ion of the TCR-zeta chain is not sufficient to activate resting T lymp
hocytes when cells from transgenic mice expressing a chimeric zeta rec
eptor are used. However, after (in vivo and in vitro) activation throu
gh their endogenous TCR/CD3 complexes, the preactivated T lymphocytes
could be triggered through the zeta chimera to the same extent as when
they were activated through their endogenous TCR/CD3 complexes. They
were able to proliferate and elicit cytotoxic functions when triggered
through their zeta chimeras. These results suggest that the triggerin
g requirements for effector functions seem to be different in resting
than in activated T cells.