Clinical and Experimental Rheumatology 2001; 19: 317-320. BRIEF PAPER T lymphocytes in the ABSTRACT in the pathogenesis of the disease (4). Objective. To assess the percentage of The human CD 134 (OX40) cell sur- synovial fluid of patients T ly m p h o cy t e s , b e a ring CD134, a faceantigen, a 50-kDa membrane-asso- with active rheumatoid member of the TNF receptor superfam - ciated glycoprotein, is a member of the arthritis display CD134- i ly, p ri m a ri ly found on autore a c t ive tumor necrosis factor (TNF) receptor CD4+ T cells in the peripheral blood superfamily, which is found primarily OX40 surface antigen (PB) and synovial fluid (SF) of rheu - on activated CD4+ cells and not on matoid arthritis (RA) patients. normal resting peripheral blood lym- R. Giacomelli, M e t h o d s . The surface ex p ression of phocytes (5). Its interaction with the A. Passacantando, CD134 on SF and PB mononu cl e a r specific ligand (CD134L – OX40L), a 1 cells was performed by flow cytometry type II membrane protein (6) generally R. Perricone , in 25 RA patients and correlated to the expressed on activated B lymphocytes I. Parzanese, M. Rascente, disease activity. (7), antigen presenting cells, and acti- G. Minisola2, G. Tonietti Results. CD134 expression on CD3+, vated endothelial cells (8) is, on one CD4+, CD8+ and CD25+ cells was hand, an efficient costimulatory signal Clinica Medica, University of L’Aquila; higher in SF than in PB of RA patients for CD4+ T cell-dependent humora l 1Immunologia Clinica, University of Tor ( P < 0.001). No diffe rences we re ob - immune responses (9), resulting in the Vergata; 2Santo Spirito-Villa Betania served in the percentage of CD134+/ induction of IL-4 production by naive T Hospital, Rome, Italy. CD4+ T lymphocytes in the PB of RA cells and their development into effec- Please address correspondence and p atients and controls. Patients with tor cells producing higher levels of this reprint requests to: R. Giacomelli, MD, active RA had significantly higher per - cytokine (10), thus enhancing B-cell Clinica Medica, Department of Internal centage of CD3+/CD134+, CD4+/ CD proliferation and immunoglobulin se- Medicine, University of L’Aquila, 134+,CD8+/CD134+and CD25+/ CD cretion (9) and, on the other hand, an via Vetoio, 67100 L’Aquila, Italy. 134+ than those with inactive disease. event mediating the adhesion of lym- E-mail: [email protected] C o n clusion. These findings sugge s t phocytes to endothelial cells and leuko- Received on July 11, 2000; accepted in that CD134+ T cells are involved in the cyte recruitment (8). revised form on November 7, 2000. i m mu n o p at h o l ogical process of RA The CD134 molecule shows a distinct © Copyright CLINICAL AND synovitis, maybe mirroring some other p at t e rn of ex p ression in autoimmu n e EXPERIMENTAL RHEUMATOLOGY 2001. autoimmune disease in which autore - d i s e a s e s , in that it is ex p ressed on active T cell infiltrating the target tis - CD4+ autoreactive T cells, in the in- Key words: Rheumatoid arthritis, sues largely coexpress CD134. flammatory infiltrates of experimental CD134, TNF-receptors superfamily. autoimmune encephalomyelitis (EAE) Introduction ( 1 1 ) , i n fl a m m at o ry bowel disease Rheumatoid arthritis (RA) is a disease (IBD) (12) and acute graft-versus host of unknown aetiology, in which several disease (aGVHD) (13), but not in their T cell-dependent immune mechanisms ci rc u l ating CD4+ cells. Furt h e rm o re, are involved in the pathogenesis, inclu- s e l e c t ive depletion of OX 4 0 + / C D 4 + ding T cell migration and their recruit- c e l l s , in EAE, induces stab i l i z at i o n ment and activation in the synovia with and/or disease prevention, via elimina- consequent cytokines release (1). The tion of autoantigen re a c t ive T cells majority of T lymphocytes infiltrating (14), suggesting a potential role for tar- RA joints express CD4 molecules and geting OX40+ cells as a strategy in the specific autoreactive T cells are present control of autoimmune diseases. in this CD4+ population (2). In this study, given the specificity of In the last years, on the basis of their CD134 for autoreactive CD4+ T cells, cytokines production,T cells have been we evaluated whether this molecule is divided into two distinct subsets, mod- overexpressed in RA. Thus, we asses- ulating different immune responses (3): sed the percentage of CD134+ T lym- T helper 1 (Th1) cells, mainly produc- phocytes in peripheral blood (PB) and ing interleukin-2 (IL-2) and interferon- synovial fluid (SF) of RA patients and (IFN- ) and Th2 cells, mainly pro- we analysed the possible correlations ducing IL-4, IL-5 and IL-10. Recent of these findings with clinical and labo- studies have shown that CD4+ T lym- ratory parameters of disease activity. phocytes, isolated from RA joints, pro- duced high levels of IFN- and low lev- Patients and methods els of IL-4, suggesting a dominance of Patients Th1 immune responses with conse- Twenty-five patients, 20 women and 5 quent proinflammatory role for T cells males, median age 48 years (range 17- 317 BRIEF PAPER CD134 in active RA / R. Giacomelli et al. 75 years), who met the revised criteria (PBMC) we re sep a rated from paire d ried out with samples of PB and SF of the American Rheumatism Associa- samples of SF and PB by standard from 25 patients with RA. As shown in tion for RA (15) were enrolled in the Ficoll-Hypaque density gradient centri- Fi g u re 1, the perc e n t age of CD3+/ study. Fifteen displayed early RA (dur- fugation. Their viability, as assessed by CD134+ cells is significantly increased ation of disease less than two years); in trypan blue dye exclusion, was routine- in SF (12.5%, range 5-34%) compared 10 patients the disease had been present ly > 95%. The SF had been pre-treated to PB (2%, range 0-5%) (p < 0.001). for 4 to 25 years. Eighteen patients had for 30 min at 37°C by the addition of CD134 expression on CD4+ cells was IgM rheumatoid factor, median titer 54 10 units/ml of ovine hyaluronidase. higher in SF (12%, ra n ge 5.7-28%) IU/ml (range 26-400) and 97.8 IU/ml than in PB (0.8%, range 0.1-4.4%) (P < (range 68-600) in the serum and SF, Flow cytometric analysis of PBMC 0.001). Similarly, the perc e n t age of respectively. The surface coexpression of OX-40 on CD134+/CD8+ cells from SF (7%, Disease activity was defined by the SF and PB mononu clear cells wa s range 0.5-12%) was significantly high- presence of at least 3 of the following determined by two-color immunofluo- er than the percentage observed in PB criteria: > 6 joints tender or painful on rescence staining, after incubation with (0.25%, range 0.1-4%) (p<0.001). Fur- motion, > 3 swollen joints, increase of a FITC or PE-conjugated anti-OX 4 0 thermore, in RA patients,an increase of We s t e rgren ery t h ro cyte sedimentat i o n MoAb (PharMinge n , La Jo l l a , C A ; CD134+ cells in SF displaying the acti- rate (ESR) > 28, morning stiffness > 45 Becton Dick i n s o n , Mountain Vi ew, vation marker CD25 (p55 IL2 receptor) minutes in duration, both patient’s and CA; respectively) in combination with was observed compared to PB cells (SF physician’s analog scale for the global A n t i - C D 3 , - C D 4 , - C D 8 , - C D 2 5 CD134+/CD25+ cells: 9%, range 1.3- assessment of disease activity > 50. MoAbs FITC or PE-conjugated (all 15% vs PB CD134+/CD25+ cells: Thirteen patients with early RA had not MoAbs were from Becton Dickinson, 0.5%, range 0.1-6.3%) (p < 0.001). Of p rev i o u s ly taken disease-modifying Montain View, CA, USA). Phenotypic interest, no differences were observed antirheumatic drugs (DMARDs), 1 was analysis was performed by flow cytom- in the percentage of CD134+/CD4+ T re c e iving sulphasalazine and another etry (FACScan; Becton Dickinson). lymphocytes in the PB of RA patients was taking 10 mg/die of prednisone. and controls (Fig. 2). All patients with chronic disease were Statistical analysis Patients with active RA had significant- receiving DMARDs (5 sulphasalazine, Data was expressed as median (range). ly higher perc e n t age of CD3+/CD 2 hy d rox y ch l o roquine and 3 metho- Because of non-normal distribution of 134+, CD4+/CD134+, CD8+/CD134+ trexate). samples, the Mann-Whitney U test for and CD25+/CD134+ than those with Twenty sex- and age-matched healthy n o n - p a i red samples and Wi l c ox o n ’s inactive disease (Fig. 3). No differences volunteers, with the same demographic s i g n e d - rank test for paired data and were observed in RA patients accord- findings of the studied populat i o n , Spearman’scorrelation coefficient were ing to the kind of therapy. Furthermore, served as controls. used for statistical analysis of the data. no diffe rences we re observed in the p e rc e n t age of CD4+/CD134+ and Isolation of synovial fluid and PBMC Results CD8+/CD134+ ly m p h o cytes betwe e n Pe ri p h e ral blood mononu clear cells I m munophenotypic studies we re car- new onset and chronic synovitis.