Disruption in Th1/Th2 immune response in young adult smokers

Interferon (IFN)-γ and IL-10 cytokines, measures of Th1 and Th2 immunity, were examined in 20 healthy nonsmokers (12 males, 8 females) and 19 smokers (11 males, 8 females), aged 19-41 years (23.46 ± 0.82 years). Nonsmokers came to the laboratory once; smokers came to the laboratory after ad lib smoking and following 24-h smoking abstinence. Salivary cotinine and expired CO confirmed smoking status. Plasma was collected at the end of each lab session and assayed for peripheral IFN-γ and IL-10 levels. Among smokers, peripheral IFN-γ, IL-10, or IFN-γ/IL-10 ratio levels did not change in response to 24-h smoking abstinence. IFN-γ levels and IFN-γ/IL-10 ratios were higher among female smokers while smoking and following 24-h abstinence compared to male smokers in both conditions and compared to male and female nonsmokers. There was no sex or smoking status difference in IL-10 levels. Results suggest that cigarette smoking may have at least short-term damaging effects on the body's normal immune balance, particularly for women.