Conclusion
Altogether, our data provide a novel function of miR-181c-5p in macrophage biology and suggest that targeting macrophage miR-181c-5p in injured tissues might improve clearance of dead cells and lead to efficient inflammation resolution.
Methods
miR-181c-5p was identified as a potential candidate in microRNA screening of RAW264.7 macrophages fed with apoptotic cells. To investigate the role of miR-181c-5p in phagocytosis, the expression of miR-181c-5p was assessed in phagocyting bone marrow-derived macrophages. Phagocytosis efficiency was measured by fluorescence microscopy. Gain- and loss-of-function studies were performed using miR-181c-5p-specific mimic and inhibitor. The expression of the phagocytosis-associated genes and proteins of interest was evaluated by RT2 profiler PCR array and western blotting, respectively.
Results
miR-181c-5p expression was significantly upregulated in the phagocyting macrophages. Furthermore, mimic-induced overexpression of miR-181c-5p resulted in the increased phagocytic ability of macrophages. Moreover, overexpression of miR-181c-5p resulted in upregulation of WAVE-2 in phagocyting macrophages, suggesting that miR-181c-5p may regulate cytoskeletal arrangement during macrophage phagocytosis.