Within the CD4 T lymphocytes subset we found that the CD45RO- (naive) cells selectively in RA displayed higher levels of CD25 protein and of interferon-gamma mRNA expression when compared with the respective subset of all other investigated groups.
In addition, our observation that CD14 density was increased on a subset of circulating blood monocytes in active RA, that HLA-DR was not significantly altered and that Fc gamma RI and Fc gamma RII were increased in both active and inactive RA is not compatible with the expected actions of interferon gamma.
Macrophage activation and class II expression are prominent features in rheumatoid arthritis (RA) joints, but the mechanism of their stimulation is not understood, since interferon-gamma, the major stimulus of class II expression, is not usually detectable at the protein level in synovial cell culture supernatants.
We demonstrate here a significantly decreased expression of IFN-gamma mRNA in RA patients without modification of its kinetics associated with a similar IL-1 beta mRNA expression.
Neutralization of the endogenous IL-10 in two out of seven RA synovial membrane cultures resulted in the expression of detectable levels of interferon gamma (561-1,050 pg/ml).
Immunofluorescence analysis of CD27 expression by CD4 lymphocytes from the peripheral blood of healthy humans or rheumatoid arthritis (RA) patients and from the synovial fluid (SF) of RA patients was carried out, along with the estimation of cytokine gene [interleukin (IL) 2, IL-3, IL-4, IL-5, IL-6, IL-6R, IL-10 and interferon-gamma (IFN-gamma)] expression in these lymphocyte subsets by RT-PCR.
To investigate whether T cells in the inflamed joints of patients with rheumatoid arthritis (RA) preferentially produce the T helper 1 (Th1) cytokines, interferon-gamma (IFN gamma) and interleukin-2 (IL-2), or the Th2 cytokine, IL-4, when compared with corresponding peripheral blood-derived T cells.
We have investigated the potent influence of some cytokines, tumour necrosis factor-alpha (TNF-alpha), platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF) and interferon-gamma (IFN-gamma), on the secretion of cysteine proteinases (cathepsins B and L) by cultured synovial fibroblast-like cells from patients with rheumatoid arthritis (RA).
In vitro, under the action of MTX, IL-10 gene expression was significantly increased in the 3 groups, IL-4 gene expression was significantly increased in RA group 1 and in the control group, and IL-2 and IFNgamma gene expression was significantly decreased in RA group 1.
TNF-alpha and IL-1beta stimulated PTHrP expression in synoviocytes, while dexamethasone and interferon-gamma, agents with some therapeutic efficacy in the treatment of RA, inhibited PTHrP release.
Using flow cytometry and a three-step cellular ELISA method, we determined whether SP has an influence on the expression of MHC class II, intercellular adhesion molecule-1 (ICAM-1), VCAM-1, LFA-3, CD40, B7.1 or B7.2 molecules on RA FLS incubated with interferon-gamma (IFN-gamma) or IL-1beta or tumour necrosis factor-alpha (TNF-alpha) with or without SP.
The local synthesis in synovial fibroblasts and their induction by IFN-gamma and dexamethasone, but not by tumour necrosis factor-alpha, suggests for each of the two complement regulators a protective role in RA.
Moreover, the CD97 isoform pattern was not altered in monocytes after interferon-gamma stimulation and in synovial T cells from patients with rheumatoid arthritis.
The cytokine production in the MNC obtained from the SF (SF-MNC) in 30 patients with RA and 10 with gout was examined by measuring the mRNA levels of IFNgamma, IL-12, IL-4 and IL-10 by semiquantitative RT-PCR.
Interferon-gamma production in response to in vitro stimulation with collagen type II in rheumatoid arthritis is associated with HLA-DRB1(*)0401 and HLA-DQ8.
A recent report noted an allele (126 bp [CA(13)]) of the interferon-gamma intron A microsatellite repeat strongly associated with both the occurrence and the severity of RA.
Basal IL-4, IL-6, IL-10, and TNF-alpha levels were similar for both groups; however, basal IFN-gamma levels were slightly higher in patients with RA compared to controls.