IL27 and chronic obstructive pulmonary disease: Of the seven marker candidates evaluated in the initial (discovery) phase, only soluble ICAM‐1 (sICAM‐1) and IL‐27 were found to be increased in sera from patients with exacerbated COPD (P < 0.05), though neither achieved statistical significance after Bonferroni correction (P < 0.05/7 = 0.0071; Table 3).