IMMUNITY TO CARTILAGE LINK PROTEIN IN PATIENTS WITH JUVENILE RHEUMATOID-ARTHRITIS

Objective. To determine whether children with juvenile rheumatoid arth ritis (JRA) express cellular immunity to cartilage link protein. Metho ds. Link protein was purified from human fetal epiphyseal and bovine a dult nasal cartilage. It was used in proliferation assays with the per ipheral blood lymphocytes isolated from 54 children with JRA and 22 no narthritic controls. Results. Patients with JRA expressed a significan tly higher prevalence of cellular proliferation to human link protein compared with the control group, independent of whether they had pauci articular, polyarticular, or systemic disease. In the case of bovine l ink protein, significant differences were only noted for the polyartic ular group. There was significant correlation between the immunity to bovine and to human link proteins. Furthermore. immune responses to bo th molecules correlated with measures of joint disease activity. Concl usion. These results suggest that immunity to link protein may play a role in the pathogenesis of JRA.