Lung epithelial lining fluid T cell subsets defined by distinct patterns of beta 7 and beta 1 integrin expression.
Integrins are heterodimeric cell-surface glycoproteins that mediate cell-cell and cell-matrix adhesion. We previously identified cDNA encoding a novel integrin beta subunit, beta 7, from bronchoalveolar lavage fluid (BALF) leukocytes. The beta 7 subunit protein is now known to associate with at least two integrin alpha subunits on lymphocytes. One beta 7 integrin, alpha 4 beta 7, mediates lymphocyte adhesion to endothelium and to fibronectin. The other known beta 7 integrin, alpha E beta 7, has recently been shown to mediate lymphocyte-epithelial cell adhesion in vitro. We used flow microfluorometry to analyze the expression of alpha 4 beta 7, alpha E beta 7, and other integrins on blood T cells and epithelial lining fluid T cells obtained from five healthy adult volunteers by bronchoalveolar lavage. alpha 4 beta 7 was the predominant beta 7 integrin on blood T cells, whereas alpha E beta 7 was predominant on BALF T cells. BALF T cells could be divided into alpha E beta 7- and alpha E beta 7+ subsets. Between 29 and 61% (mean 42%) of CD3+ T cells were alpha E beta 7+ alpha E beta 7 was more likely to be present on CD8+ T cells (mean 69% alpha E beta 7+) than on CD4+ T cells (mean 29% alpha E beta 7+). The alpha E beta 7- and alpha E beta 7+ BALF T cell subsets were also found to differ in their expression of other integrins.(ABSTRACT TRUNCATED AT 250 WORDS)
Erle
D J
DJ
Lung Biology Center, San Francisco General Hospital, California.
Brown
T
T
Christian
D
D
Aris
R
R
D000328:Adult; D000911:Antibodies, Monoclonal; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D003592:Cytophotometry; D005260:Female; D006801:Humans; D039641:Integrin beta Chains; D019012:Integrin beta1; D016023:Integrins / Q000096:biosynthesis*; D008168:Lung / Q000166:cytology; D008213:Lymphocyte Activation; D008297:Male; D016176:T-Lymphocyte Subsets / Q000145:classification / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D039641:Integrin beta Chains; D019012:Integrin beta1; D016023:Integrins; D016212:Transforming Growth Factor beta; C070709:integrin alphaEbeta7; C091368:integrin beta7