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.
Kilshaw
P J
PJ
AFRC Institute of Animal Physiology and Genetics Research, Department of Cell Biology, Babraham, Cambridge, GB.
Murant
S J
SJ
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