M2 Macrophages derived exosomes promoted Periodontal ligament stem cells osteogenic differentiation through secreting CCL18.

Abstract

<h4>Purpose</h4>This research aimed to examine the impact of M2 Macrophages-derived exosomes (M2-exo) on the osteogenic differentiation of Periodontal Ligament Stem Cells (PDLSCs).<h4>Methods</h4>Human monocytes THP-1 were used to induce the M1 and M2 polarization. The PDLSCs were co-cultured with M1 and M2 type THP-1, and subjected to M2-exo treatment, respectively. The osteogenic differentiation of PDLSCs was analyzed through ALP and ARS staining. The mRNA expression of biomarkers of M1 and M2 macrophages, OPN, Runx2, ALP and CCL18 was evaluated by RT-qPCR assay.<h4>Results</h4>The findings suggested that M1 type THP-1 inhibited the steogenic differentiation of PDLSCs and M2 type THP-1 promoted it. M2-exo also promoted steogenic differentiation of PDLSCs and increased the OPN, Runx2 and ALP mRNA levels. Furthermore, CCL18 levels were increased in M2 type THP-1 and M2-exo treated PDLSCs. After CCL18 knockdown, the role of M2-exo in PDLSCs was reversed.<h4>Conclusion</h4>In conclusion, this study confirmed that M2-exo derived exosomes facilitated PDLSCs' osteogenic differentiation through secreting CCL18.