NEUTROPHIL ACTIVATION IN SMOKERS

Smoking and elevated leukocyte counts are risk factors for cardiovascu lar disease, Experimental studies suggest that leukocyte activation ma y be a requirement for certain cardiovascular complications, Clinical studies have demonstrated activated leukocytes in the peripheral blood of stroke victims, Accordingly, neutrophil activation in unseparated whole blood of smokers as well as naive neutrophils of non-smokers exp osed to plasma of smokers was investigated, Both spontaneous superoxid e formation as determined by nitroblue tetrazolium reduction, as well as pseudopod formation, are significantly elevated in autologous: neut rophils of smokers, The surface expression of CD18 and L-selectin on a utologous circulating neutrophils of smokers is not significantly diff erent from non-smoker controls, In contrast, incubation of naive neutr ophils with smoker plasma leads to significantly higher levels of supe roxide formation, pseudopod formation, and L-selectin shedding compare d with non-smoker plasma, suggesting that the plasma of smokers contai ns a transferable factor which causes leukocyte activation, The result s indicate that analysis of blood samples from large peripheral veins may not accurately reflect leukocyte activation in the circulation sin ce activated leukocytes have a higher probability to be trapped in the microcirculation.