| First Author | Grillot DA | Year | 1995 |
| Journal | J Exp Med | Volume | 182 |
| Issue | 6 | Pages | 1973-83 |
| PubMed ID | 7500043 | Mgi Jnum | J:30597 |
| Mgi Id | MGI:78096 | Doi | 10.1084/jem.182.6.1973 |
| Citation | Grillot DA, et al. (1995) Bcl-XL displays restricted distribution during T cell development and inhibits multiple forms of apoptosis but not clonal deletion in transgenic mice. J Exp Med 182(6):1973-83 |
| abstractText | The survival of T lymphocytes is tightly controlled during development. Here, we show that Bcl-xL, a protein homologue of Bcl-2, is highly regulated in the thymus in a pattern different than that of Bcl-2. The maximum expression was in CD4+CD8+ thymocytes, a developmental stage where Bcl-2 is downregulated. To assess the role of Bcl-xL in thymocyte apoptosis, we generated mice overexpressing an E mu-bcl-x transgene within the T cell compartment. Constitutive expression of Bcl-xL resulted in accumulation of thymocytes and mature T cells in lymphoid organs. Thymocytes overexpressing Bcl-xL exhibited increased viability in vitro and were resistant to apoptosis induced by different signals, including glucocorticoid, gamma irradiation, calcium ionophore, and CD3 cross-linking. However, Bcl-xL was unable to block clonal deletion of thymocytes reactive with self-superantigens or H-Y antigen. These studies demonstrate that Bcl-2 and Bcl-xL, two functionally related proteins, are regulated independently during T cell development. In contrast to Bcl-2, which has been implicated in the maintenance of mature T cells, Bcl-xL appears to provide a survival signal for the maintenance of more immature CD4+CD8+ thymocytes before positive selection. |
