The acute influence of tobacco smoking on adhesion molecule expression on monocytes and neutrophils and on circulating adhesion molecule levels in vivo.

Soluble adhesion molecules have been reported as risk markers of a wide range of human diseases and specific adhesion molecules may play a direct role in pathological processes. Serum soluble intercellular adhesion molecule-1 (sICAM-1) is known to be significantly elevated in smokers compared to non-smokers. We examined the acute effects of smoking a standard 2R1 research cigarette on the serum concentration of sICAM-1 and other circulating adhesion molecules (sP-selectin, sE-selectin, sL-selectin, sVCAM-1 and sPECAM-1) in heavy smokers (serum cotinine >/= 100 ng/ml), light smokers (serum cotinine </= 60 ng/ml) and non-smokers (serum cotinine </= 10 ng/ml) by ELISA. Adhesion molecule expression on the cell surface of monocytes and neutrophils in peripheral blood was examined by flow cytometry. The sICAM-1 concentration directly correlated to serum cotinine concentration (p= 0.047) and nicotine load (p= 0.033) in smokers and was significantly elevated compared to non-smokers (p= 0.037). Other than a decrease in the concentration of sP-selectin over 1 hour regardless of smoking, no significant temporal alterations of any adhesion molecule were observed following the smoking experience or in the non-smoking control group. No significant difference in surface expression of ICAM-1, CD18, PECAM-1 or L-selectin on peripheral monocytes or neutrophils was observed over a 1-hour period following smoking. These data suggest that the elevated concentration of sICAM-1 in smokers is not due to an immediate effect of smoking.