Intracellular FPR3 expressions of NK cell (2.2 ± 0.4 vs. 2.9 ± 0.5 MFI, adjusted p < 0.001, Fig. 2c), NK T cell (2.8 ± 2.1 vs. 4.9 ± 3.7 MFI, adjusted p = 0.004, Fig. 2d), Th cell (2.1 ± 0.4 vs. 2.8 ± 0.6 MFI, adjusted p < 0.001, Fig. 2e), and Tc cell (2.1 ± 0.5 vs. 2.8 ± 0.6 MFI, adjusted p < 0.001, Fig. 2f) were all significantly lower in the COPD patients as compared with that in the healthy non-smokers. Here, FPR3 is linked to chronic obstructive pulmonary disease.