TNF and chronic obstructive pulmonary disease: The above findings were also confirmed in a different trial [65] in which white blood cell (WBC) count and levels of CRP, IL-6, IL-8, fibrinogen, and TNF-a were measured in peripheral blood in 1755 COPD patients, showing that the exacerbation frequency was substantially higher in patients who were persistently inflamed than in those who were not.