Comparison of mesenchymal stem cells derived from gingival tissue and periodontal ligament in different incubation conditions.

Gingival tissue-derived mesenchymal stem cells (MSCs) were recently identified and characterized as having multipotential differentiation and immunomodulatory properties in vitro and in vivo, and they represent new postnatal stem cell types for cytotherapy and regenerative medicine. However, the utility of gingival MSCs (GMSCs) as alternatives to periodontal ligament stem cells (PDLSCs), which have been demonstrated to be effective but with limited cell availability and reduced clinical feasibility, for periodontal regeneration in a previously diseased/inflamed environment remains obscure. In this study, patient-matched human GMSCs and PDLSCs were evaluated in terms of their colony-forming ability, proliferative capacity, cell surface epitopes, multi-lineage differentiation potentials, and related gene expression when incubated in different designed culture conditions, with or without the presence of inflammatory cytokines. An in vivo ectopic transplantation model using transplants from inflammatory cytokine-treated or untreated cells was applied to assess bone formation. We found that cells derived from both tissues expressed MSC markers, including CD146, CD105, CD90, CD29, and STRO-1. Both cells successfully differentiated under osteogenic, adipogenic, and chondrogenic microenvironments; PDLSCs displayed a more effective differentiation potential in all of the incubation conditions compared to GMSCs (P < 0.01). Although inflammatory cytokine-treated GMSCs and PDLSCs are inferior to normally cultured, patient and tissue-matched cells in terms of their osteogenic capacity and regenerative potential (P < 0.05), they retain the capacity for osteoblastic and adipose differentiation, as well as ectopic bone formation, similar to what has been demonstrated for other MSCs. Interestingly, GMSCs exhibited fewer inflammation-related changes in terms of osteogenic potential in vitro and bone formation in vivo compared to PDLSCs (P < 0.01). These results suggest that both gingiva and PDL tissues are putative cell sources for future cytotherapeutic applications. Whether GMSCs act as an adjunctive or alternative cell source for cytotherapy of inflammatory periodontal disease warrants further investigation.

Yang H ，Gao LN ，An Y ，Hu CH ，Jin F ，Zhou J ，Jin Y ，Chen FM ... -  《-》

The differentiation potential of gingival mesenchymal stem cells induced by apical tooth germ cell‑conditioned medium.

Chen Y ，Liu H 《-》

The effect of aging on the pluripotential capacity and regenerative potential of human periodontal ligament stem cells.

Multipotent postnatal stem cells can be isolated from human periodontal ligaments (PDLs) and have the potential for large-scale expansion, offering a reliable cell source for clinical use in periodontal regenerative therapies. However, the effects of aging on the mesenchymal stem cell (MSC) properties of these cells remain undefined. The aims of this study were to isolate and characterize the periodontal ligament stem cells (PDLSCs) derived from human impacted third molars of donors of different ages and to compare their pluripotential capacity and regenerative potential. PDL tissues were obtained from 90 surgically extracted third molars and divided into four groups according to the donor's age. For each group, the colony-forming ability, proliferative capacity, migratory potential, cell surface antigens, differentiation ability, alkaline phosphatase activity, and gene expression of the PDLSCs were contrastively evaluated and quantified for statistical analysis. The in vivo tissue regenerative potential of PDLSCs was assessed by an in vivo ectopic transplantation model. It was found that human PDLSCs were successfully isolated and characterized as MSCs in all 90 teeth. PDLSCs derived from donors of different ages were successfully differentiated under an osteogenic and adipogenic microenvironment. The proliferative and migratory potential and the differentiation capacity of PDLSCs decreased as age increased (p < 0.05). PDLSCs derived from donors whose age is 62.6 ± 6.8 have a statistically significant decrease in pluripotential capacity compared with those derived from relatively young donors (p < 0.01). There is no identified cementum and PDL-like tissue formation in vivo among the two aging groups. We conclude that human PDLSCs could be successfully isolated from PDL tissue derived from donors of different ages, but the age-related changes of the MSC properties should be taken into account whenever they are intended for use in research or cytotherapy.

Zhang J ，An Y ，Gao LN ，Zhang YJ ，Jin Y ，Chen FM ... -  《-》

Mesenchymal stem cell characteristics of dental pulp and periodontal ligament stem cells after in vivo transplantation.

Mesenchymal stem cells (MSCs) isolated from human postnatal dental pulp and periodontal ligament (PDL) tissues can give rise to multilineage differentiation in vitro and generate related dental tissues in vivo. However, the cell properties of human dental pulp stem cells (DPSCs) and PDL stem cells (PDLSCs) after in vivo implantation remain largely unidentified. In this study, cells were re-isolated from in vivo-generated dental pulp-like and PDL-like tissues (termed re-DPCs and re-PDLCs, respectively) as a result of ectopic transplantation of human DPSC and PDLSC sheets. The cell characteristics in terms of colony-forming ability, cell surface antigens and multi-differentiation potentials were all evaluated before and after implantation. It was found that re-DPCs and re-PDLCs were of human and mesenchymal origin and positive for MSC markers such as STRO-1, CD146, CD29, CD90 and CD105; and, to some extent, re-DPCs could maintain their colony forming abilities. Moreover, both cell types were able to form mineral deposits and differentiate into adipocytes and chondrocytes; however, quantitative analysis and related gene expression determination showed that the osteo-/chondro-differentiation capabilities of re-DPCs and re-PDLCs were significantly reduced compared to those of DPSCs and PDLSCs, respectively (P < 0.05); re-PDLCs showed a greater reduction potential than re-DPCs. We conclude that DPSCs and PDLSCs may maintain their MSC characteristics after in vivo implantation and, compared to PDLSCs, DPSCs appear much more stable under in vivo conditions. These findings provide additional cellular and molecular evidence that supports expanding the use of dental tissue-derived stem cells in cell therapy and tissue engineering.

Lei M ，Li K ，Li B ，Gao LN ，Chen FM ，Jin Y ... -  《-》

Isolation and multiple differentiation potential assessment of human gingival mesenchymal stem cells.

Gao Y ，Zhao G ，Li D ，Chen X ，Pang J ，Ke J ... -  《INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES》