Early Expression of FcγRI (CD64) on Monocytes  of Cardiac Surgical Patients and 
Higher Density of  Monocyte Anti-Inflammatory Scavenger CD163  Receptor in “On-Pump” Patients
OBJECTIVE
Activation of innate immunity cells is inseparably linked to cardiac surgical operation. The aim of this study was to assess the kinetics in the expression of receptor for Fc part of IgG, FcgammaRI (CD64), and scavenger receptor CD163 on peripheral blood cells of cardiac surgical patients and to examine the effect of cardiac bypass as a separable influence on the systemic acute inflammatory response.


METHODS
Forty patients, twenty in each group, were randomly assigned to CABG surgery performed either with "on-pump" or without "off-pump" cardiopulmonary bypass. Standardized quantitative flow cytometry method was used to determine the expression of surface markers.


RESULTS
The density of CD64 molecule on monocytes reached maximum on the 1st postoperative day (P<.001) whereas the peak for CD64 molecule expression on granulocytes was postponed to the 3rd postoperative day (P<.001). The expression of CD163 scavenger molecule on monocytes reached maximum on the 1st postoperative day (P<.001). The density of CD163 molecule on monocytes on the 1st postoperative day is significantly higher in "on-pump" patients in comparison with "off-pump" patients (P<.001).


CONCLUSION
In cardiac surgical patients the expression of activation marker FcgammaR1 (CD64) on monocytes is increased earlier in comparison with granulocytes in both "on-pump" and "off-pump" patients. The expression of scavenger molecule CD163 on monocytes is significantly higher in "on-pump" patients.