Expression of the LFA-1 beta 2 integrin (CD11a/CD18) and ICAM-1 (CD54) in normal and coeliac small bowel mucosa.
The leucocyte adhesion molecules (beta 2 integrins) comprise CD11 alpha-chains and a common beta-chain (CD18). CD11a (leucocyte function-associated antigen 1, LFA-1) is expressed by most T cells, and is involved in antigen presentation by macrophages via its counter-receptor, intercellular adhesion molecule (ICAM-1, CD54). By criteria of double-label immunofluorescence of cryostat tissue sections, virtually all lamina propria T cells of the normal small bowel were found to express LFA-1 strongly. By contrast, only 30-60% of intra-epithelial lymphocytes (IEL) expressed detectable LFA-1, most of which were LFA-1 weak and CD18-. ICAM-1 was expressed strongly only by vascular endothelium. In coeliac disease, there was a modest increase of diffuse ICAM-1 expression in the lamina propria, mainly in the subepithelial zone, where ICAM-1+ macrophages were occasionally seen. There was also a slight overall increase in CD11a expression by IEL, seen predominantly in surface epithelium and mainly by the CD4+ minority subset, but not by CD4-CD8- (TcR gamma delta +) cells. These data suggest that the LFA-1/ICAM-1-dependent antigen presentation pathway is of minor importance to IEL in the normal small bowel, and does not assume a major role in coeliac disease.
Department of Medicine, St James's University Hospital, University of Leeds, UK.
C J
CJ
Smart
A
A
Calabrese
D J
DJ
Oakes
P D
PD
Howdle
L K
LK
Trejdosiewicz
D015703:Antigens, CD / Q000032:analysis; D018821:CD18 Antigens; D002446:Celiac Disease / Q000276:immunology* / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000032:analysis*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1; D007413:Intestinal Mucosa / Q000737:chemistry / Q000276:immunology*; D007421:Intestine, Small / Q000737:chemistry / Q000276:immunology*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis*
D015703:Antigens, CD; D018821:CD18 Antigens; D015815:Cell Adhesion Molecules; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1