Expression and functional role of 1F7 (CD26) antigen on peripheral blood and synovial fluid T cells in rheumatoid arthritis patients.
The expression and the functional role of the CD26 (1F7) T cell surface molecule, an ectoenzyme which seems to represent a functional collagen receptor of T lymphocytes and to have a role in T cell activation, were analysed in both peripheral blood (PB) and synovial fluid (SF) T cell samples from patients with active and inactive rheumatoid arthritis (RA). Although patients with active disease displayed higher percentages of PB CD26+ CD4+ T cells than inactive RA and control subjects, CD26 antigen expression on RA SF T lymphocytes was low. The anti-1F7 binding to the T cell surface, that led to CD26 antigen modulation and enhancement of both IL-2 synthesis by, and 3H-TdR incorporation of, anti-CD3- or anti-CD2-triggered PB T cells in RA and control subjects, was unable to affect significantly both expression and functional activity of RA SF T lymphocytes. Since the 1F7 antigen spontaneously reappeared on the surface of unstimulated SF T cells after 2-5 days of culturing, the low 1F7 antigen expression of anti-1F7 in the SF T cell compartment may be the result of in vivo molecule modulation exerted by the natural ligand in the joint, with important implications for T cell activation and lymphokine synthesis.
Institute of Internal Medicine and Oncologic Sciences, University of Perugia, Italy.
C
C
Muscat
A
A
Bertotto
E
E
Agea
O
O
Bistoni
R
R
Ercolani
R
R
Tognellini
F
F
Spinozzi
M
M
Cesarotti
R
R
Gerli
D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D018819:Dipeptidyl Peptidase 4 / Q000096:biosynthesis* / Q000276:immunology* / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D007376:Interleukin-2 / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D013582:Synovial Fluid / Q000166:cytology / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D007376:Interleukin-2; D018819:Dipeptidyl Peptidase 4