Finally, although we observed decreases in expression of FcγRI and MSR-1 in COPD macrophages compared to CNS, we did not determine whether Siglec-1dim-neg macrophages also lost expression of FcγRI and MSR-1 or if decreased receptor expression in COPD alveolar macrophages had less specificity. This evidence concerns the gene MSR1 and chronic obstructive pulmonary disease.