Tissue factor pathway inhibitor promotes the migration, proliferation and colonization of MSCs by regulating CXCL12/CXCR4 signaling pathway.

MSCs (mesenchymal stem cells) can promote the structural and functional recovery of lung injury, but most of MSCs do not retain in the injury sites. TFPI (tissue factor pathway inhibitors) can promote stem/progenitor cell migration and homing. The objective of this study was to clarify the feasibility and efficacy of TFPI combined with MSCs in alleviating lung injury and explore the possible mechanism. rhTFPI or (and) MSCs were administered via tail vein to LPS-induced ALI mice. Lung H&E, coagulation function, TFPI, TNF-α, IL-1β, CXCL12 and CXCR4 in BALF and plasma, 7-day survival rate, and colonization of MSCs in lung were observed. Transmembrane migration assay, CCK-8 and EdU assay were used to determine the migration, viability and proliferation of MSCs. RNA sequencing was performed to find differentially expressed genes. The lentivirus transfection technique was used to infect MSCs to overexpession and knockdown TFPI of MSCs. The data demonstrated that rhTFPI could promote cell viability, proliferation and migration of MSCs to improve lung injury. RNA sequence indicated that CXCL12 was in top 40 DEGs and up-regulated after the combination treatment of rhTFPI and MSCs. LPS dampened TFPI, CXCL12/CXCR4 levels in a dose- and time-dependent manner, but can restored by rhTFPI. The level of TFPI expressed by MSCs affected the levels of CXCL12/CXCR4 in MSCs, and migration, proliferation and colonization of MSCs. The results indicated that TFPI may promote the migration, proliferation and colonization of MSCs by regulating CXCL12/CXCR4 signaling pathway.