CXCL12 overexpression promotes the angiogenesis potential of periodontal ligament stem cells
Periodontal ligament stem cells (PDLSCs) are a major source of mesenchymal stem cells (MSCs) in adults and are effective for tissue engineering, like promoting angiogenesis and bone regeneration. CXCL12 has been reported to be involved in the recruitment and engraftment of MSCs in wound sites. However, whether CXCL12 potentiates the angiogenesis of PDLSCs is not clear. In this experiment, we transduced PDLSCs with CXCL12, and evaluated the angiogenesis potential of CXCL12-modified PDLSCs through in vitro and in vivo studies. The results showed that CXCL12 overexpression significantly stimulated the gene and protein expressions of bFGF, VEGF, SCF and PLGF in PDLSCs; CXCL12 gene modified PDLSCs formed longer capillary‐like structure; Moreover, in vivo transplanted PDLSCs transduced with CXCL12 could significantly promote bone tissue repair and angiogenesis in a rat critical-sized calvarial bone defect model. Taken together, our study confirmed that CXCL12 can enhance the angiogenesis potential of PDLSCs, which are crucial in the repair and regeneration of bone tissue.The flow cytometry analysis (Supporting Fig. S1A) showed that PDLSCs expressed mesenchymal stem cells markers, like CD90, CD44 and CD105. CD45 was not detected.The results of Oil Red O (Supporting Fig. S1B) and alkaline phosphatase (Supporting Fig. S1C) staining showed that PDLSCs possessed multilineage differentiation potential.Human PDLSCs were isolated and cultured according to previously published protocols by Seo et al.5 and Zhang et al.7. Teeth and periodontal ligament tissues were obtained from healthy male patients (18–25 years old) without any history of periodontal disease who were undergoing third molar extractions. Written informed consent was provided by all patients, and ethical approval was obtained from the Ethics Committee of the School of Stomatology, Shandong University. Briefly, periodontal ligament tissues were gently separated from the surface of the root and digested in the solution of collagenase type I (Worthington Biochem) and dispase (Roche) for 1 h at 37 °C. Single-cell suspensions were obtained by passing the cells through a 70 µm filter. To identify the PDLSCs, single-cell suspensions (1 × 104 cells) were seeded into 10-cm culture dishes (Costar) with α minimum essential medium (αMEM) (Gibco BRL) supplemented with 10% fetal calf serum (Gibco, Inc.), 100 mM ascorbic acid 2-phosphate (Sigma-Aldrich), 2 mM glutamine, 100 U/mL penicillin, and 100 mg/mL streptomycin (Sigma-Aldrich) and then incubated at 37 °C in 5% CO2.This work was supported by National Natural Science Foundation of China (No. 81070864) and the Construction Engineering Special Fund of “Taishan Scholars’’. The funders had no role in the study design, data collection or analysis, the decision to publish, or the preparation of the manuscript.The authors declare that they have no competing interests.Electronic supplementary materialSupplementary information accompanies this paper at doi:10.1038/s41598-017-10971-1Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.