Altered expression of alpha E beta 7 integrin on intra-epithelial and lamina propria lymphocytes in patients with Crohn's disease.
OBJECTIVE
To compare the expression of adhesion molecules on intestinal intra-epithelial (IEL) and lamina propria T cells (LPL) from ileum and colon, in patients with Crohn's disease (CD) versus healthy controls, with special reference for the alpha E beta 7 integrin.


METHODS
IEL and LPL were obtained from 18 CD patients and 20 controls by enzymatic extraction, and subsequently characterized by flow cytometry for CD3, CD4, CD8, CD25, LFA-1 alpha (CD11a), CD44, alpha 4 and alpha E beta 7 integrin.


RESULTS
In LPL of controls, a decreased CD4/CD8 ratio was noted in ileum compared to colon. This regional difference was accompanied by a higher expression of alpha E beta 7 integrin in ileum versus colon. In LPL from left hemicolon of CD patients, a decreased CD4/CD8 ratio was noted versus controls. alpha E beta 7 expression on T cells of LPL did not discriminate CD from controls. However, an overexpression of this beta 7 integrin member was observed on CD25+ T cell subsets from lamina propria of left hemicolon, in CD versus controls. Moreover, in IEL, profound alterations in alpha E beta 7 integrin were observed in CD, compared to controls. A decreased expression of alpha E beta 7 was noted in IEL of ileum of CD patients. This was also apparent in non-inflamed mucosa.


CONCLUSIONS
The observed changes of alpha E beta 7 integrin expression in CD patients versus controls are of pathogenic relevance, especially the decreased expression of alpha E beta 7 in IEL of non-inflamed CD mucosa. This may be one of the earliest events in the pathogenesis of this disease.
Elewaut
D
D
Department of Rheumatology, University Hospital Ghent, Belgium.
Van Damme
N
N
De Keyser
F
F
Baeten
D
D
De Paepe
P
P
Van Vlierberghe
H
H
Mielants
H
H
Cuvelier
C
C
Verbruggen
G
G
Veys
E M
EM
De Vos
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000032:analysis*; D015703:Antigens, CD / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D001707:Biopsy, Needle; D016516:CD4-CD8 Ratio; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000276:immunology; D002478:Cells, Cultured; D003106:Colon / Q000166:cytology / Q000276:immunology; D003424:Crohn Disease / Q000276:immunology* / Q000473:pathology; D004848:Epithelium / Q000737:chemistry; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D007082:Ileum / Q000166:cytology / Q000276:immunology; D039641:Integrin beta Chains; D016023:Integrins / Q000032:analysis*; D007413:Intestinal Mucosa / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000737:chemistry; D012016:Reference Values; D012680:Sensitivity and Specificity; D013601:T-Lymphocytes / Q000737:chemistry* / Q000276:immunology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D015415:Biomarkers; D015815:Cell Adhesion Molecules; D039641:Integrin beta Chains; D016023:Integrins; C091368:integrin beta7