Growing evidence suggests that anti-Hsp60
antibodies might be involved in the pathogenesis of different
autoimmune diseases. Attempts were reported also on the characterization of
epitope specificity of anti-Hsp60
antibodies in different infectious and
autoimmune diseases. However, there is a lack of data on the occurrence and
epitope specificity of anti-Hsp60
antibodies in the healthy human antibody repertoire. Therefore, the aim of our study was to demonstrate the presence of anti-Hsp60
antibodies and to investigate the
epitope specificity of these
antibodies using a large set of synthetic 10 mer
peptides covering regions of Hsp60 with high probability of antigenicity. Here we report the identification of several linear
epitopes using serum Ig (
IVIG) and sera from healthy subjects by ELISA assay. We have identified two
epitopes 'specific' for human Hsp60 and two different
epitopes 'specific' for Hsp65. In addition, six
epitopes were cross-reactive in nature, detected on both
proteins. The presence of these 'specific'
epitopes may explain the differences in
epitope structure between Hsp60 and Hsp65 observed earlier in patients with
cardiovascular disease. The binding of the
IVIG preparation to Hsp60
epitopes might indicate that anti-Hsp60
autoantibodies are present in the healthy human natural
autoantibody repertoire.