CCL5 and chronic obstructive pulmonary disease: Combining p38 inhibitors BIRB-796/SB706504 with corticosteroids in COPD patients can synergistically enhance the secretion of anti-LPS cytokines of alveolar macrophages, including IL-8, IL-6, TNF, IL-10, RANTES (Regulated on Activation, Normal T-cell Expressed and Secreted; CCL5), GM-CSF, IL-1β, IL-1ra, and MDC [37, 38, 78] (Table 1 and Fig. 3).