| First Author | Yada S | Year | 1998 |
| Journal | J Immunol | Volume | 161 |
| Issue | 5 | Pages | 2208-16 |
| PubMed ID | 9725213 | Mgi Jnum | J:111646 |
| Mgi Id | MGI:3654612 | Doi | 10.4049/jimmunol.161.5.2208 |
| Citation | Yada S, et al. (1998) Differential requirements of CD45 protein tyrosine phosphatase for cytolytic activities and intrathymic and extrathymic development of intestinal intraepithelial lymphocytes. J Immunol 161(5):2208-16 |
| abstractText | CD45 is a transmembrane protein tyrosine phosphatase essential for Ag receptor-mediated signaling in both T and B cells. In this study we investigated roles of CD45 in development and cytolytic activities of murine intestinal intraepithelial lymphocytes (i-IEL) using CD45 exon 6 knockout (CD45-/-) mice. Interestingly, the total cell number of i-IEL was significantly reduced in CD45-/-mice during aging (10-20 wk of age), whereas the i-IEL number was normally increased in the wild-type littermates. Especially, the number of gamma(delta)TCR+ i-IEL decreased markedly in CD45-/- mice during aging. The i-IEL in CD45-/- mice were more susceptible to in vitro spontaneous apoptosis than the normal i-IEL, implying that CD45 is required for maintenance of the cellularity of i-IEL. Results from in vivo analyses of the extrathymic and intrathymic development of i-IEL suggested that CD45-mediated signaling is required for the intrathymic, but not the extrathymic, development of i-IEL. Moreover, the whole i-IEL from CD45-/- mice showed a significantly reduced cytolytic activity, and the residual cytolytic activity was completely diminished by depleting CD45+ i-IEL, suggesting that CD45 is indispensable for the TCR-mediated cytolytic activity of i-IEL. Furthermore, we found differential contributions of CD45 and p56lck to development and induction of cytolytic activities of i-IEL. |
