Expression and regulation of beta 7(beta p) integrins on mouse lymphocytes: relevance to the mucosal immune system.
A mouse lymphocyte surface molecule which is selectively expressed by mucosal T cells and detected with the monoclonal antibody (mAb) M290 has provisionally been identified as a beta 7 integrin. Identification was based on close homology of its beta subunit at the N terminus with the recently reported, highly distinctive, human beta 7 sequence. mAb were prepared against the beta and alpha subunits of the mouse molecule, termed beta 7 and alpha M290, respectively, and used to study surface expression of the two components. beta 7 was present on most lymph node lymphocytes in association with alpha 4 rather than alpha M290. This integrin, beta 7 alpha 4, was shown to be identical to LPAM-1 (beta p alpha 4) the Peyer's patch homing receptor. Stimulation in vitro of mouse lymph node T cells with anti-CD3 in the presence of transforming growth factor (TGF)-beta increased beta 7 expression in about 40% of cells and changed the associated alpha chain from alpha 4 to the novel alpha M290 subunit, which, in most cells, was expressed de novo. Immunoprecipitation of beta 7 both from these cells and from intraepithelial lymphocytes gave closely similar results and showed predominance of the beta 7 alpha M290 integrin. It is suggested that in vivo this change in alpha-chain usage occurs in mucosal T cells in response to TGF-beta acting in the mucosal microenvironment and that the new integrin confers particular adhesive properties, possibly homing specificity, on the cells.
AFRC Institute of Animal Physiology and Genetics Research, Department of Cell Biology, Babraham, Cambridge, GB.
P J
PJ
Kilshaw
S J
SJ
Murant
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D015153:Blotting, Western; D005434:Flow Cytometry; D016023:Integrins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology*; D008198:Lymph Nodes / Q000166:cytology; D046911:Macromolecular Substances; D051379:Mice; D010581:Peyer's Patches / Q000166:cytology / Q000276:immunology; D011233:Precipitin Tests; D013601:T-Lymphocytes / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D016023:Integrins; D046911:Macromolecular Substances; D016212:Transforming Growth Factor beta