The cytokine network is even more developed in COPD patients with increased nodes of IL-1β, IL-6 and TNFα (p < 0.001 in comparison to both healthy non-smokers and healthy smokers for all three parameters) as well as IL-8 (p < 0.05 in comparison to healthy non-smokers). This evidence concerns the gene IL6 and chronic obstructive pulmonary disease.