CD4 and chronic obstructive pulmonary disease: Major proinflammatory and T-cell cytokines involved in COPD includes TNFα, IL1β, IL6, IL8, IL2 and IFNɣ [88, 94] where pro-inflammatory cytokines are released by the NF-κB pathway and T cell cytokines IL2 and IFNɣ derive from CD4+ T cells type II [94, 95].