Enrichment of T cells carrying beta7 integrins in inflamed synovial tissue from patients with early spondyloarthropathy, compared to rheumatoid arthritis.
OBJECTIVE
To compare the expression of adhesion molecules on synovial T cells from patients with early spondyloarthropathy (SpA) and rheumatoid arthritis (RA), with special reference to the beta7 integrins alpha4beta7 and alphaEbeta7 in view of their intimate association with intestinal tissue.


METHODS
Twenty-five synovial cell lines were generated by interleukin 2 (IL-2) expansion from synovial biopsies of patients with early SpA and RA, obtained from macroscopically inflamed synovial tissue by needle arthroscopy, and subsequently characterized by flow cytometry for CD3, CD4, CD8, L-selectin, CD11a, CD31, CD44, and alpha4beta7 and alphaEbeta7 integrin.


RESULTS
In SpA, the beta7 integrin expression was increased, compared to RA. Furthermore, an inverse relation between alpha4beta7 and alphaEbeta7 was present in SpA (r = -0.75, p < 0.02), as on many mucosal T cells. In contrast, an opposite correlation was noted in RA (r = +0.84, p < 0.01), as similarly described on a subset of circulating T cells.


CONCLUSIONS
Increased expression of beta7 integrins was noted on synovial T cell lines from SpA compared to RA, with discriminative correlations between alpha4beta7 and alphaEbeta7. This suggests a different origin of the synovial T cells in these diseases.
Elewaut
D
D
Department of Rheumatology, University Hospital Ghent, Belgium.
De Keyser
F
F
Van Den Bosch
F
F
Lazarovits
A I
AI
De Vos
M
M
Cuvelier
C
C
Verbruggen
G
G
Mielants
H
H
Veys
E M
EM
D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D001168:Arthritis / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D039001:Integrin alpha Chains; D039441:Integrin alpha4; D039641:Integrin beta Chains; D016023:Integrins / Q000378:metabolism*; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D013583:Synovial Membrane / Q000276:immunology*; D013601:T-Lymphocytes / Q000166:cytology* / Q000378:metabolism
D015703:Antigens, CD; D039001:Integrin alpha Chains; D039641:Integrin beta Chains; D016023:Integrins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; C091367:alpha E integrins; C091368:integrin beta7; D039441:Integrin alpha4