Influence of nicotine on monocyte phenotype and function

Monocyte expression of class II antigens was studied in smokers and in nonsmokers using double marker analysis and flow cytometry. There was no difference in class II expression with 78.8% and 79.3% class II+ monocytes in smokers and nonsmokers, respectively. Further, in vitro treatment with nicotine at levels seen in smokers (50 ng/ml) did not alter class II expression either. When analyzing TNF production using the Wehi 164/ActD 51Cr-release assay we observed a two-fold lower TNF production in smokers versus nonsmokers. In vitro treatment of monocytes with nicotine, however, did not reduce the LPS triggered TNF production.