Among the signals received by macrophages, we observed that MIF-(CD74+CD44), CCL3-CCR1, CCL3-CCR5, CCL4-CCR5, CCL5-CCR1, CCL5-CCR5, ANXA1-FPR1, and ANXA1-FPR3 were upregulated in COPD compared with HS (Figure 7F). Here, CD74 is linked to chronic obstructive pulmonary disease.