In contrast, cells of smokers and COPD patients did not respond to LPS stimulation with increased TLR2 expression (7.09 ± 1.42 vs. 6.59 ± 1.42 rMFI [smokers], p = n.s.; 6.63 ± 2.40 vs. 6.24 ± 1.71 rMFI, [COPD patients], p = n.s.)(figure 3a). Here, TLR2 is linked to chronic obstructive pulmonary disease.