ALTERATION OF CHLAMYDIA-TRACHOMATIS BIOLOGIC BEHAVIOR IN SYNOVIAL MEMBRANES - SUPPRESSION OF SURFACE-ANTIGEN PRODUCTION IN REACTIVE ARTHRITIS AND REITERS-SYNDROME

Objective. To investigate the biologic state of Chlamydia and its surf ace antigen expression in the synovial membranes of patients with Chla mydia-associated reactive arthritis/Reiter's syndrome (ReA/RS). Method s, Expression of chlamydial lipopolysaccharide (LPS), major outer memb rane protein (MOMP), and elementary body (EB) antigens was studied by gold labeling immunoelectron microscopy on 6 synovial membrane and 2 s ynovial fluid (SF) pellet samples from 6 patients with Chlamydia-assoc iated arthritis. The study findings were compared with 24-hour culture s of HeLa cells infected with Chlamydia trachomatis EB, Results, Persi stent C trachomatis infection was found in all 6 synovial membrane sam ples from patients who had either early or chronic arthritis, The infe ction persisted despite antibiotic treatment, including a 1-month cour se of doxycycline therapy. Most persistent organisms were atypical ret iculate bodies (RBs) found in both fibroblasts and macrophages. Specif ic, but weak, immunogold staining for all 3 antibodies was found on bo th intracellular RBs and extracellular EBs, In the SF samples, Chlamyd ia surface antigens were detected only in phagosomes containing degrad ed electron-dense materials. Conclusions. The synovial membrane biopsi es conducted in this study of Chlamydia-associated ReA/RS revealed aty pical RBs with diminished MOMP and LPS expression. Such altered organi sms may escape immune surveillance and contribute to disease chronicit y; moreover, these organisms may be difficult to detect and treat in s ome ReA/RS patients.