| First Author | Williams O | Year | 2001 |
| Journal | Eur J Immunol | Volume | 31 |
| Issue | 6 | Pages | 1876-82 |
| PubMed ID | 11433384 | Mgi Jnum | J:115405 |
| Mgi Id | MGI:3691542 | Doi | 10.1002/1521-4141(200106)31:6<1876::aid-immu1876>3.0.co;2-f |
| Citation | Williams O, et al. (2001) Elevated Bcl-2 is not a causal event in the positive selection of T cells. Eur J Immunol 31(6):1876-82 |
| abstractText | T cell development is characterized by the induction of apoptosis in most immature thymocytes and the rescue from apoptosis of a small proportion of cells by the process of positive selection.Up-regulation of the anti-apoptotic molecule Bcl-2 is associated with thymocytes undergoing positive selection and a bcl-2 transgene promotes the generation of mature T cells. In contrast,mice transgenic for the pro-apoptotic molecule Bax show impaired T cell maturation. We have used fetal thymic organ culture to determine the action of Bcl-2 and Bax on positive selection of thymocytes. Our data show that Bcl-2 and Bax do not alter the number of thymocytes positively selected by a defined peptide ligand. This implies that Bcl-2 and Bax alter the production of mature T cells in vivo by influencing thymocyte viability rather than by direct action on positive selection. It also presents a solution to the 'chicken-and-egg' scenario relating to Bcl-2 up-regulation and positive selection. The data suggest that the up-regulation of Bcl-2 associated with T cell maturation is a consequence of positive selection rather than a cause of it. |
