[70 kDa heat-shock proteins in surgical stress: thoracotomy vs. herniorrhaphy]

During and after surgical procedures, there is an oxidative stress response that releases cytokines and reactive oxygen species. This can activate Heat Shock Response (HSR), leading to an increase in Heat Shock Proteins (HSPs) expression proportional to the intensity of the stimulus.

This study examined the biology of intraleucocyte Hsps70 and IL-6 as potential biomarkers of postoperative inflammatory stress, and a potential antiHsp70 autoimmune reaction in patients undergoing two surgical procedures of different severity.

Longitudinal cohort study including a group of patients undergoing thoracotomy under general anaesthesia (n=11), a group of patients undergoing inguinal hernia repair under regional anaesthesia (n=10), and a group of healthy controls (n=6). Intraleucocyte Hsps70, antiHsp70 antibodies and IL-6 were analysed, just before and 24h after surgery.

Patients undergoing thoracotomy showed a significant decrease in intraleucocyte Hsp70 and antiHsp70 antibodies in the early postoperative period; patients with the greatest Hsp70 decreases after surgery showed the lowest pre-surgical Hsp70 levels and these patients also experienced various postoperative complications. A significant postoperative increase in IL-6 levels in both groups was observed.

Patients undergoing a more aggressive surgery showed a significant Hsp70 reduction in the postoperative period. Patients with the lowest values of Hsp70 in the immediate postoperative period had the worst clinical course, which has led to propose use of Hsp70 as a prognostic post-surgical marker. The postoperative decrease in intracellular Hsp70 is parallel to the decrease in circulating autoantibodies. The different response of both groups to surgical stress is not due to systemic inflammatory response, but to HSR.