CCL4 and chronic obstructive pulmonary disease: Table 2 shows the mean (± SD) concentrations of cytokines in sputum in the three groups: in patients with COPD, the levels of cytokines such as IL-1RA, IL-1α, IL-1β, MIP-1β, sCD40L and VEGF were statistically higher compared to the control group with p-values ​​all lower at 0.05.