Abstract
Peyer's patch (PP) organogenesis proceeds through three histologically distinct steps: formation of organizing centers expressing VCAM-1 and ICAM-1 in segregated regions of the intestine at 15.5 days post-coitus (d.p.c.) (step I), accumulation of blood cells expressing different sets of surface markers to this region at 16.5-17.0 d.p.c. (step II), and entry of CD3+ and B220+ lymphocytes just before birth (step III). PP formation of both II7ra(-/-) and Lta(-/-) mice is impaired from step I, suggesting involvement of the two molecules at the same timing in PP organogenesis. Expression of lymphotoxin (LT) α and LTβ in IL-7 receptor (IL-7R) α+ cells in the intestine indicates that defects of II7ra(-/-) and Lta(-/-) mice are due to functional inability of IL-7Rα+ cells in the induction of PP anlage. Blocking of IL-7Rα function by a single injection of the antagonistic mAb in 15.5 d.p.c. embryos suppressed appearance of VCAM-1+ spots and expression of LTα and LTβ in the intestine, which eventually resulted in mice without PP but are otherwise normal, Intestinal IL-7Rα+ cells are lymphoid in morphology but CD3- and functional in both nu/nu and Rag2(-/-) mice. These results implicate IL-7Rα+ CD3- cells as the direct inducer of the organizing center of PP.
Original language | English |
---|---|
Pages (from-to) | 643-655 |
Number of pages | 13 |
Journal | International immunology |
Volume | 11 |
Issue number | 5 |
DOIs | |
Publication status | Published - 1999 |
Keywords
- Development
- IL-7Rα
- Lymphotoxin
- Organizing center
- Peyer's patch
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology