Isolation And Characterization Of Mesenchymal Stem Cells From Granulomas Of Periodontal-endodontic Combined Lesions

Periodontal-endodontic combined lesions(perio-endo lesions)is an infectious odontogenic disease that results in endodontic and periodontal lesions.It is intractable to treat and can lead to tooth extraction.The presence of mesenchymal stem cells(MSCs)in the granulomas of perio-endo lesions,and their function remain unclear.Objectives: The aim of this research was to isolate and characterize MSCs from perio-endo lesion granulomas.Methods:(1)Granuloma tissues of perio-endo lesions were collected from patients with periodontal-endodontic combined lesions after tooth extraction,and adherent cells were isolated and cultured by tissue block enzymolytic method.Periodontal ligament mesenchymal stem cells(PDLSCs)were used as comparison.(2)MSC marker expression was detected by flow cytometry,proliferation ability was detected by Ed U kit.The differentiation ability was evaluated by osteogenic and adipogenic induction.(3)To test the in vitro immunomodulatory ability of PEMSCs,they were co-cultured with activated T cells and their ability to induce apoptosis of activated T cells was detected;their immunomodulatory ability in vivo was analyzed by injecting cells into the ulcerative colitis mise model through tail vein.Results:(1)Fibroblast-like cells were successfully isolated from the granulomas of perio-endo lesions,which could adhere to cell culture flasks and form colonies;(2)The isolated cells had self-renewal ability,expression of MSC surface markers was similar to that of PDLSCs,named as PEMSCs.They had similar proliferation ability to PDLSCs and could induce osteogenic and adipogenic differentiation in vitro,but their differentiation ability was slightly decreased compared with PDLSCs.(3)Similar to PDLSCs,PEMSCs could induce apoptosis of activated T cell in vitro,and effectively alleviated clinical and histopathological symptoms in ulcerative colitis mice in vivo,demonstrating immunoregulatory ability in vivo and in vitro.Conclusion: MSCs from granulomas of perio-endo lesions were successfully isolated and characterized.Their biological characteristics,including morphology,cell surface markers,proliferation and immunomodulatory properties,are similar to those of PDLSCs,but their differentiation ability is comparatively lower.The isolation of PEMSCs can help us better understand the pathology mechanism of perio-endo lesions and seek more effective treatment methods.