Sepsis, surgical stress, and anesthesia are often associated with postoperative immune suppression and an increased susceptibility to infection. Apoptosis is an important mechanism of cell death in sepsis and Endotoxemia, and the apoptosis-induced loss of lymphocytes may be responsible for immune depression. To access the possible role of propofol on human immune function in sepsis, we investigated the apoptosis of mononuclear cells (MNCs) and lymphocyte from peripheral blood.

Healthy human mononuclear cells were isolated and stimulated with lipopolysaccharide (LPS) for 5 hrs. And, activated MNCs were cultured in the presence of varying concentrations of propofol (1 microgram/ml, 5 microgram/ml, 10 microgram/ml and 50 microgram/ml) for 20 hrs. The apoptotic indices of LPS-treated MNCs, monocytes and lymphocytes were calculated by flow cytometry using an Annexin-V-FLUOS staining kit.

Propofol exposure at 1, 5 and 10 microgram/ml did not significantly affect apoptosis of the LPS-treated MNCs, monocytes or lymphocytes, but a concentration of 50 microgram/ml increased the apoptosis of MNCs and lymphocytes significantly (P < 0.01).

Since the concentrations of propofol used were in the clinically acceptable range for sedation and anesthesia, this result suggests that propofol does not significantly alter the apoptosis of NMCs, monocytes or lymphocytes in septic conditions for up to 20 hrs.