Expression of CD200/CD200R regulatory molecules on granulocytes and monocytes is modulated by cardiac surgical operation

Aims: Cardiac surgical operation is inseparably linked to the induction of an inflammatory response. Both humoral and cellular regulatory mechanisms are operating to maintain body homeostasis. We followed the changes in the expression of CD200/CD200R regulatory molecules on monocytes and granulocyte of cardiac surgical patients operated on using either standard (OP) or modified "mini-invasive" cardiopulmonary bypass (MOP). Methods: Expression of CD200/CD200R regulatory molecules was determined by flow cytometry. Results: The expression of CD200R on granulocytes was increased after surgery in both groups of patients, but the increase was statistically significant only in OP patients (p<0.01). At this time point, there was a significant difference in CD200R expression on granulocytes when comparing OP to MOP patients, being higher in the former group (p<0.01). The expression of CD200R on monocytes was diminished after surgery and during an early postoperative period in both groups of patients. The expression of CD200 on monocytes was significantly diminished after surgery in both groups (p<0.01). Nonetheless, we observed an increase in CD200 expression in OP patients at the 3(rd) postoperative day. There was a statistically significantly increased CD200 expression on monocytes of OP patients (p<0.001) at the 3(rd) postoperative day when we compared OP and MOP groups. The expression of CD200 on granulocytes was significantly higher after surgery and at the 3(rd) postoperative day in OP when compared to MOP patients. Conclusions: CD200R expression on granulocytes was significantly increased, while CD200 and CD200R expression on monocytes was decreased after cardiac surgery.