Normal macrophage functions, but impaired induction of γδ T cells, at the site of bacterial infection in CD45 exon 6-deficient mice
✍ Scribed by Shigeru Fujise; Kenji Kishihara; Kyung-Yil Lee; Goro Matsuzaki; Kikuo Nomoto
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 916 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0014-2980
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
We investigated the protective functions of macrophages and γδ T cells in adult CD45 exon 6‐deficient (CD45−/−) mice against an intraperitoneal (i.p.) infection with Listeria monocytogenes. γδ T cells are preferentially localized in the spleen, liver, and intraperitoneal cavity of the adult CD45−/− mice. Increased numbers of γδ T cells were observed after i.p. infection with L. monocytogenes in the peritoneal cavity of C57BL/6 (CD45+/+) mice but not in CD45−/− mice. The γδ T cells showed predominant usage of Vδ5 and Vδ6 rearranged to Jδ1 in the infected CD45−/− mice which are the same as those used by resident γδ T cells of noninfected CD45+/+ and CD45−/− mice. Furthermore, we analyzed the protective abilities of the CD45−/−, CD45+/+, and γδ T cell‐depleted mice at the early stage of the listerial infection. The numbers of bacteria in the spleens and livers of the CD45−/− mice 5 days after the listerial infection were almost ten times larger than those in the CD45−/− and γδ T cell‐depleted CD45+/+ mice. Macrophages showed normal antigen presentation, nitric oxide production and bactericidal activity for L. monocytogenes despite their lacking CD45 surface expression, suggesting that CD45‐negative macrophages have a minimal influence on the increased bacterial multiplication in the CD45−/− mice. These results suggest that the γδ T cells are induced by the bacterial infection in a CD45‐dependent manner, and that unresponsiveness of the γδ T cells results in only weak protection against L. monocytogenes in CD45−/− mice.