Rhh. Pieters et al., THE THYMUS ATROPHY INDUCING ORGANOTIN COMPOUND DBTC STIMULATES TCR-ALPHA-BETA-CD3 SIGNALING IN IMMATURE RAT THYMOCYTES, Biochemical and biophysical research communications, 214(2), 1995, pp. 552-558
In the present study, we show that the thymus atrophy inducing compoun
d DBTC stimulates the intracellular release, but not the influx, of Ca
2+ elicited by cross-linking of the TcR alpha beta-CD3-complex on rat
thymocytes and inhibits capping of TcR alpha beta. Similarities with t
he effects of cytochalasin B together with the finding that DBTC also
inhibited capping of CD8, whereas cross-linking of CD8 did nest cause
a Ca2+-response, suggest that DBTC interferes with TcR alpha beta-CD3-
signalling by selective interference with cytoskeletal functioning. Th
e responding thymocytes were CD53- and FSClow, thus possibly including
the non proliferating counterpart of the presumed immature CD4-CD8(+)
CD53- target cells of DBTC. The present effects may therefore relate t
o the mechanisms of organotin-induced thymus atrophy. (C) 1995 Academi
c Press, Inc.