| First Author | Wallace VA | Year | 1997 |
| Journal | J Immunol | Volume | 158 |
| Issue | 7 | Pages | 3205-14 |
| PubMed ID | 9120275 | Mgi Jnum | J:110837 |
| Mgi Id | MGI:3641379 | Doi | 10.4049/jimmunol.158.7.3205 |
| Citation | Wallace VA, et al. (1997) Alterations in the level of CD45 surface expression affect the outcome of thymic selection. J Immunol 158(7):3205-14 |
| abstractText | CD45 is a receptor protein tyrosine phosphatase whose activity is required for thymocyte development and TCR-mediated signal transduction. Here we show that positive selection of TCR-alphabeta transgenic thymocytes is completely blocked in CD45 exon 6 -/- gene-deficient (CD45 -/-) mice that express the P14 TCR specific for the lymphocytic choriomeningitis virus. Thymocytes from mice heterozygous for the targeted disruption of the CD45 gene (CD45 +/-) displayed a reduction in both CD45 surface intensity and enzymatic CD45 protein tyrosine phosphatase activity. Surprisingly, positive thymocyte selection was enhanced in CD45 +/- mice as characterized by an up-regulation of the P14 TCR on thymocytes and increased numbers of transgenic T cells. Using a variant of lymphocytic choriomeningitis virus that is impaired in the induction of negative selection of P14 thymocytes, we also show that the reduction of CD45 surface expression in CD45 +/- mice rendered P14 transgene thymocytes susceptible to negative selection. These data demonstrate that changes in the expression level of the receptor protein tyrosine phosphatase CD45 can alter thymic selection. |
