Fine particulate matter () exposure is proved to be associated with illnesses, but the mechanism is not clear. Potential effects of on innate immunity have become a hotspot recently. Confronting , macrophages are able to be activated and induce inflammatory responses. Whether exposure affects macrophage polarization and associated mechanisms remains to be further explored. | upregulates microRNA-146a-3p and induces M1 polarization in cells by targeting sirtuin1