Furthermore, MCP-4/eotaxin-3 expression signature also showed AUC values of 0.6182/0.6002 in differing AECOPD from stable COPD patients, with sensitivity of 38.26/39.33% and specificity of 76.42/78.66% (Figures 2(e) and 2(f)). Here, CCL26 is linked to chronic obstructive pulmonary disease.