ANTIBODIES TO STREPTOCOCCAL CELL-WALL IN PSORIATIC-ARTHRITIS AND CUTANEOUS PSORIASIS

Objective, To evaluate the possible role of streptococcal cell wall an tigens in the development of psoriatic arthritis. Methods. IgM, IgA an d IgG class serum antibodies against peptidoglycan-polysaccharide (PG- PS) and peptidoglycan (PG), both front group A streptococcus, were mea sured in patients with psoriatic arthritis (PA), non-arthritic psorias is (NAP), rheumatoid arthritis (RA) and in healthy controls, using ELI SA. Results. Both groups of psoriatic patients had elevated IgA levels specific to streptococcal PG-PS. No association with the severity of the skirt disease or with the different subsets of PA was detected Hig her concentrations of IgG against the two streptococcal preparations w as observed in PA than in RA. Analysis of antibody levels in patients with recent onset arthritis showed lower concentrations of IgM antibod ies against streptococcal as well as control antigens in early than in late PA, whereas an overall increase of specific IgA and IgG antibodi es was observed in early RA. Conclusion. The results suggest chronic m ucosal stimulation of lymphocytes by long-lived streptococcal antigens in patients with psoriasis, without any difference observed between P A and NAP. The differences between recent onset versus established PA and RA could reflect a distinct immunopathology in the two arthritides .