Expression of the human heat shock protein 60 in thyroid, pancreatic, hepatic and adrenal autoimmunity

Heat shock proteins (hsps) have been proposed to play a role in autoimmune disease. Their highly conserved nature and role as a common antigenic determinant throughout phylogeny has raised the possibility that they may act as cellular targets of an autoimmune response when their expression is altered in stressed tissue cells. Using an antibody to human hsp60 we have demonstrated a wide tissue distribution in normal tissues, including thymus, the degree of staining reflecting the content of mitochondria in the cells, consistent with the known mitochondrial location of this protein. Enhanced staining was also demonstrated in oncocytes (deeply eosinophilic cells which have greatly increased numbers of mitochondria) in both thyroid and adrenal autoimmune disease and also in unrelated conditions where oncocytic change was identified. No enhancement was demonstrated in target cells in organ specific autoimmune diseases where oncocytic change was not seen, for example islet cells in diabetes and bile duct cells in primary biliary cirrhosis. Thus, no alteration of hsp60 expression was demonstrated which was specific to the autoimmune diseases studied.