Presence of antibodies to heat stress proteins and its possible significance in workers exposed to high temperature and carbon monoxide.

ABSTRACT

Antibodies to the ubiquitous group of stress proteins known as heat shock proteins (Hsps) have been found to be associated with a number of diseases in humans. Hsps are known to be induced by certain xenobiotics, some of which are common in the working environment. The biological significance of the presence of such autoantibodies is presently unclear. In the present study, we used immunoblotting to investigate the presence of antibodies against the different stress proteins, Hsp27, Hsp60, Hsp71, Hsc (heat shock cognate) 73 and Hsp89 alpha and beta in groups of workers exposed to high temperature or carbon monoxide. These data were related to a detailed clinical evaluation and to various laboratory measurements including electrocardiogram (ECG), B echogram, white blood cell counts and typing, the activity of alanine aminotransferase (ALT), acid phosphatase (ACP) and alkaline phosphatase (ALP) and lymphocyte DNA damage. Antibodies to Hsp27 and Hsp71 were found more frequently in the high temperature and carbon monoxide-exposed groups than in controls (P < 0.05). The carbon monoxide-exposed group showed the highest incidence of anti-Hsp antibodies. Anti-Hsp60 antibodies were only detected in workers exposed to high temperature or carbon monoxide. The percentage of workers with abnormal ECG, B echogram changes and displaying hepatitis B antigen (HBsAg) was higher in the carbon monoxide group than in the control group (P < 0.05). There was a significant increase in the activity of ALT in the high temperature and carbon monoxide groups and in the activities of ACP and ALP in the carbon monoxide group (P < 0.05). The extent of DNA damage measured in lymphocytes was higher in workers from the high temperature and carbon monoxide-exposed groups. We suggest that the increased frequency of antibodies to Hsps is the result of these damages of the release of denatured Hsps and of a decrease in the phagocytic ability of macrophages in these workers. The data gathered in the present study show a statistical relation between the occurrence of antibodies against Hsps and the frequency of health problems in workers and suggest a potential role for the antibodies as useful biomarkers to assess whether workers are experiencing environmental stress.