Investigation of mesenchymal stem cells from human gingival tissue and comparision of plasticities with dental follicle derived mesenchymal stem cells

Mesenchymal stem cells draw attention for cell based therapy with their regenerative, and tissue supporting potential and immunosuppresive caharacteristics. MSCs can be isolated from several tissues such as bone marrow, umbilical cord, peripheral blood, amniotic fluid, periosteum, fat, synovial membrane and muscle. Like in different tissues, suitable MSC resources at the maxillofacial region have been investigated and related reports are published in the literature. No studies have been published in the literature about the gingival tissue which is the most easiest approachable site in the oral cavity with a high regeneration potential. Furthermore, isolation of MSCs from dental follicle tissues have been described in a few number of studies. In this study, impacted third molars of 6 patients were extracted in a routine surgical procedure and gingival/ dental follicle tissue samples was obtained during the incision and extraction period. Along all samples, MSCs with an adhesion property have been isolated and expanded in culture. Immunophenotyping was perfomed by flow cytometry and adipocyte, osteocyte, chondrocyte, and neuronal differentiation potential of these stem cells were tested and the characteristics of gingival and follicle stem cells were compared. It has been demonstrated that MSCs obtained from both tissues have a high frequency of specific stromal antigens (%60-98) such as CD105, CD 73, CD 90.Cells have been expanded through passage 8 and characterized at 2. 5. 8. passages. No differance have been determined about surface antigen expression speciality between the passages. Differantiation assays with various stimulants in the culture points out that dental follicle and gingiva derived cells have adipogenic and osteogenic differantiation capacity however there was no evidence of chondrogenic differantiation. Furthermore, with suitable stimulants alteration to neuronal cell morphology was observed. In this study there was no difference between the differantiation potentials of MSCs derived from gingival and dental follicle tissue. Because of their similarities, the detailed comparison of plating density, adhesion properties, surface antigen expressions and differantiation potentials have been performed to distinguish MSCs from fibroblasts. Initial plating density, early or late adhesion properties and surface antigen expressions did not contribute to distinguish MSCs from fibroblasts. Multilineage differantiation potential through the late passages is one of the most important criteria to distinguish MSCs from fibroblasts. The differantiation potential of gingiva and dental follicle derived cells through passage 8 denoted the MSC/progenitor specialities of these cells. Besides the differantiation potential of fibroblasts usually ends at the passage 3. In this study MSCs continuing differantiation through passage 8 was the most important criteria to separate these cells from fibroblasts which has a differantiation potential through passage 3.Obtained results suggest that the gingival tissue is considered as an alternative source of stem cells to the other intraoral stem cell sources with it is in close proximity to the recipient site and can be obtained easily by a non- invasiv method.