| First Author | Nakazato K | Year | 2007 |
| Journal | J Immunol | Volume | 178 |
| Issue | 2 | Pages | 757-64 |
| PubMed ID | 17202336 | Mgi Jnum | J:142633 |
| Mgi Id | MGI:3821844 | Doi | 10.4049/jimmunol.178.2.757 |
| Citation | Nakazato K, et al. (2007) Enforced expression of Bcl-2 partially restores cell numbers but not functions of TCRgammadelta intestinal intraepithelial T lymphocytes in IL-15-deficient mice. J Immunol 178(2):757-64 |
| abstractText | IL-15 knockout (KO) mice have severely reduced numbers of TCRgammadelta intestinal intraepithelial T lymphocytes (i-IEL), suggesting requirements of IL-15 signaling in the development or maintenance of i-IEL. To determine an involvement of survival signals via Bcl-2 in IL-15-mediated homeostasis of TCRgammadelta i-IEL, we introduced a bcl-2 transgene into IL-15 KO mice. In situ apoptosis of TCRgammadelta i-IEL was decreased in Bcl-2 transgenic (Tg) x IL-15 KO mice compared with IL-15 KO mice. The enforced expression of Bcl-2 partially restored the numbers of TCRgammadelta i-IEL in IL-15 KO mice. However, effector functions of TCRgammadelta i-IEL, including cytokine production and cytotoxic activity, were not recovered in Bcl-2 Tg x IL-15 KO mice. Importantly, TCRgammadelta i-IEL in Bcl-2 Tg x IL-15 KO mice expressed a reduced level of eomesodermin, a transcription factor critical for effector functions of NK cells and CD8(+) T cells. Similar to the case of TCRgammadelta i-IEL, enforced expression of Bcl-2 restored the numbers but not the functions of NK cells in IL-15 KO mice. These results suggest that Bcl-2-mediated survival signal is involved in the IL-15-mediated homeostasis of TCRgammadelta i-IEL and NK cells, but other signals from IL-15 are critical for inducing transcription factors, such as eomesodermin for their effector functions. |
