SYNOVIAL-FLUID T-CELL CLONES FROM OLIGOARTICULAR JUVENILE ARTHRITIS PATIENTS DISPLAY A PREVALENT TH1 TH0-TYPE PATTERN OF CYTOKINE SECRETIONIRRESPECTIVE OF IMMUNOPHENOTYPE/

The aim of the present study was to investigate the patterns of cytoki ne production by T cell clones raised from bl vivo activated synovial fluid (SF) mononuclear cells (MNC) of five patients with oligoarticula r juvenile arthritis (JA). Freshly isolated SF T cells were cultured i n vitro with low dose recombinant IL-2 and subsequently cloned by limi ting dilution. Sixty-four clones were obtained from the five patients studied. Fifty-nine clones were TCR alpha/beta(+), either CD4(+) (n = 43) or CD8(+) (n = 15). The remaining five clones were TCR gamma/delta (+), CD4(-), CD8(-). Clone immunophenotypes differed in the individual patients. Forty-four T cell clones were stimulated with phytohaemaggl utinin (PHA) and phorbol myristate acetate (PMA) and supernatants test ed for the presence of IL-2, IL-4, IL-5 and interferon-gamma (IFN-gamm a) by ELISA or bioassays. Cytokine mRNA accumulation was tested by rev erse transcriptase-polymerase chain reaction (RT-PCR). Most of 44 clon es tested released large amounts of IFN-gamma irrespective of the immu nophenotype. Of these, 27 were classified as Th1-type and 17 as Th0-ty pe based upon the IFN-gamma/IL-4 ratio in culture supernatants. Finall y, when 19 representative T cell clones were tested for pro- and anti- inflammatory cytokines, gene expression by RT-PCR, all of them were fo und to express the granulocyte-macrophage colony-stimulating factor (G M-CSF), tumour necrosis factor-alpha (TNF-alpha), IL-10 and transformi ng growth factor-beta 1 (TGF-beta 1) genes, and half of them IL-6 and IL-8 mRNA. In conclusion, T cell clones, that represent the progeny of in vivo activated SF T cells from oligoarticular JA patients, display heterogeneous immunophenotypes, but all share the ability to produce large amounts of IFN-gamma, with a predominant Th1/Th0 pattern. The ex pression of pro- and anti-inflammatory cytokine genes in these clones suggests that in vivo activated SF T cells modulate joint inflammation in a complex fashion.