| First Author | Weller M | Year | 1994 |
| Journal | Eur J Immunol | Volume | 24 |
| Issue | 6 | Pages | 1293-300 |
| PubMed ID | 8206089 | Mgi Jnum | J:18904 |
| Mgi Id | MGI:67124 | Doi | 10.1002/eji.1830240608 |
| Citation | Weller M, et al. (1994) Transforming growth factor-beta 2 induces apoptosis of murine T cell clones without down-regulating bcl-2 mRNA expression. Eur J Immunol 24(6):1293-300 |
| abstractText | Transforming growth factor-beta (TGF beta) is a potent immunosuppressive cytokine which inhibits the antigen (Ag)-dependent expansion of T cells both in vitro and in vivo by mechanisms not well defined yet. Here we report that exposure of interleukin (IL)-2-dependent T cell lines to TGF beta 2 results in apoptosis defined by morphology, nucleosomal size DNA fragmentation and in situ DNA end labeling. TGF beta 2-induced T cell apoptosis showed the following characteristics: (1) in contrast to the rapid evolution of apoptosis following IL-2 deprivation, apoptosis of T cells triggered by TGF beta 2 was delayed; (2) cycloheximide prevented TGF beta 2-induced apoptosis of CTLL-2 but not of OVA-7 T helper cells; (3) in contrast to apoptosis following IL-2 deprivation, TGF beta 2-mediated T cell apoptosis was not associated with decreased expression of the proto-oncogenes, bcl-2 or c-myc; (4) TGF beta 2-induced apoptosis was not restricted to IL-2-dependent T cell lines since the IL-4-dependent T cell line, CT.4S, as well as EL4 lymphoma cells, which grow independently of exogenous IL-2, were also susceptible to TGF beta 2-mediated apoptosis. Taken together, these data may present a novel mechanism of TGF beta 2-mediated suppression of T cell expansion in response to Ag and IL-2, the activation of the endogenous death program of apoptosis, which appears to operate independently of direct interactions of TGF beta 2 with the IL-2/IL-2 receptor system. |
