DETECTION OF HEAT-SHOCK-PROTEIN-70 (HSP70) AND ANTI-HSP70 ANTIBODIES IN THE SERUM OF NORMAL INDIVIDUALS

Heat shock or stress proteins (Hsp) are typically regarded as being in tracellular proteins that have a range of functions including the main tenance of cellular integrity. Members of the Hsp70 family of molecule s have been implicated in the processing and presentation of antigen a nd the cross reactivity of lymphocytes specific for pathogen-derived h eat shock proteins with self Hsp70 has been suggested to be an underly ing cause of certain autoimmune diseases. This study reports the prese nce of soluble Hsp70 in the peripheral circulation of normal individua ls. Concentrations of soluble Hsp70 in females were approximately twic e those in males. Circulating anti-Hsp70 antibodies were detected in a ll individuals assessed, but there were no differences between males a nd females. However, there was a significant correlation between solub le Hsp70 concentration and antibody levels in males, but not females. The physiological role for circulating heat shock proteins is intrigui ng, but currently unknown. These findings extend our previous observat ions that Hsp60 is present in the peripheral circulation and support t he proposition that soluble heat shock proteins may play a regulatory role in either the prevention or protection of pathophysiological proc esses involving inadvertent immunorecognition or cross-recognition of heat shock proteins.