INCREASED EXPRESSION OF INTERFERON (IFN)-GAMMA TOGETHER WITH IFN-GAMMA RECEPTOR IN THE RHEUMATOID SYNOVIAL-MEMBRANE COMPARED WITH SYNOVIUM OF PATIENTS WITH OSTEOARTHRITIS
Rjem. Dolhain et al., INCREASED EXPRESSION OF INTERFERON (IFN)-GAMMA TOGETHER WITH IFN-GAMMA RECEPTOR IN THE RHEUMATOID SYNOVIAL-MEMBRANE COMPARED WITH SYNOVIUM OF PATIENTS WITH OSTEOARTHRITIS, British journal of rheumatology, 35(1), 1996, pp. 24-32
Data concerning the presence of T-cell-derived cytokines in the rheuma
tic joint are conflicting, challenging the hypothesis that rheumatoid
arthritis (RA) is a T-cell-mediated disease. In this study synovial ti
ssue specimens of 11 patients with RA and eight patients with osteoart
hritis (OA) were stained for interferon-gamma (IFN-gamma) and its rece
ptor. The level of expression of IFN-gamma was compared with that in t
issue specimens of delayed-type hypersensitivity (DTH) reactions of th
e skin and of chronic tonsillitis. Furthermore, the percentage of T-ly
mphocytes which stained positive for IFN-gamma was determined using do
uble staining techniques. IFN-gamma and its receptor were detected in
all patients with RA and in 7/8 and 3/8, respectively, of patients wit
h OA. Expression of IFN-gamma (P < 0.02) and IFN-gamma receptor (P < 0
.01) in synovial tissue of patients with RA was more abundant compared
with that in patients with OA. Although IFN-gamma could be detected i
n RA synovial tissue, the level of expression was less when compared w
ith DTH reactions of the skin and tonsillitis. The percentage of CD3 cells being positive for IFN-gamma was similar to 1% in RA, whereas i
n DTH reactions of the skin it was >90% and in tonsillitis similar to
30%. We conclude that the presence of IFN-gamma and its receptor in RA
synovial tissue suggests a role for this cytokine in the ongoing immu
nological reaction of the inflamed joint.