AbstractObjective and design:
Atherosclerosis, as an inflammatory disease, is characterized by pathologically altered levels of cytokines. We investigated whether smoking affects the CD40/CD154 system and pro-inflammatory cytokines in young males without other risk factors for atherosclerosis.Subjects:
Young male smokers (n=13) and 14 non-smoking controls were investigated.Methods:
The differences in CD40/CD154 system and serum cytokines between the groups were measured using flow cytometry and ELISA.Results:
In smokers, there was a strong trend (P<0.06) for increased CD40 expression on platelets as compared with non-smokers. However, there were no significant differences in CD40 expression on monocytes or in CD154 expression on platelets and T-cells between smokers and non-smokers. There was a strong trend for increased platelet-monocyte aggregates in smokers (P<0.06). Also, smokers had slightly but not significantly elevated hsCRP and IL-6 levels, and slightly decreased TNF-α and MCP-1. Interestingly, IL-18, a cytokine which has the ability to promote both Th1 and Th2 responses, was significantly decreased in smokers group (P=0.03 vs controls).Conclusions:
In young healthy males, smoking is not associated with dramatic changes in CD40/CD154 system. However, cigarette smoke alters the secreted cytokine profile, leading to significant decrease in systemic IL-18 levels.