Background: Sequence homology and cross reactivity between microbial and human heat shock proteins (hsps) led to the concept that hsps might be involved in the etiopathogenesis of autoimmune diseases.
Objective: In our study we stimulated peripheral blood mononuclear cells (PBMC) of patients with juvenile idiopathic arthritis (JIA) and healthy controls with various hsp-derived peptides together with the whole molecules of corresponding hsp.
Methods: PBMC were cultured with recombinant human hsp60 (rh-hsp60), rh-hsp70, Mycobacterium bovis hsp65 (M.bovis hsp65), P562-571 human hsp60, P180-188 M. bovis hsp65, P450-463 human hsp70 and P545-554 cytokeratin derived synthetic peptides. Cell responses were measured after incorporation of (3)H-thymidine and expressed as stimulation indices.
Results and conclusion: We found elevated proliferative response to rh-hsp60, M. bovis hsp65 and P562-571 human hsp60 derived peptide in patients with JIA polyarthritis. Significantly elevated proliferation to P180-188 M. bovis hsp65 was found in JIA lasting more than 2 years. None of the particular clinical characteristics (RF, ANA, HLA B27 and disease activity) seemed to be associated with hsp or hsp-derived synthetic peptide proliferative response in the JIA cohort.