Abstract
Serum samples from 57 patients who were diagnosed as having early rheumatoid arthritis (RA) were examined for antibodies against native human Type II collagen by enzymelinked immunosorbent assay (ELISA) . Antibodies were detected in 43 patients (75.4%) . Follow-up studies (more than 3 years) demonstrated that 29 patients subsequently had a positive test for rheumatoid factors. The levels of anti-Type II collagen antibodies tended to be more elevated just before the appearance of active arthritis and were low or not detected during the chronic phase. When 14 seronegative patients showing monoarthritis of the hip, knee or elbow joint were examined, 12 were positive for the antibodies. These patients were found to develop chronic polyarthritis eventually and to be positive for rheumatoid factors during the course of the disease. These results suggest that the immunization against Type II collagen seems to be functionally active in RA, and that antibodies assay may serve a supportive purpose for the diagnosis of the disease.
