Human gingival fibroblasts: Isolation, characterization, and evaluation of CD146 expression

Abstract

Abstract:‎ Gingival fibroblasts (GFs) that exhibit adult stem cell-like characteristics are known as gingival ‎mesenchymal stem cells (GMSCs). Specific mesenchymal stem cell (MSC) markers have not been ‎identified to distinguish GMSCs from GFs. Recently, the cell surface molecule known as cluster of ‎differentiation (CD) 146 has been identified as a potential MSC surface marker. In the present study, we ‎investigated the differentiation potential of GMSCs based on CD146 expression.‎

GFs were isolated by two techniques: tissue explants or enzymatic digestion. GFs were cultured and ‎expanded then magnetically sorted according to CD146 expression. CD146low and CD146high cells ‎were collected, expanded, and then tested for stem cell markers by flow cytometry as well as osteogenic ‎and chondrogenic differentiation potential. The differentiation of these cells was analyzed after 21 days ‎using histology, immunofluorescence, real-time quantitative PCR (qPCR), and glycosaminoglycan (GAG) ‎to DNA ratio (GAG/DNA) assays. Positive histological staining indicated osteogenic differentiation of all ‎groups regardless of the isolation techniques utilized. However, none of the groups demonstrated ‎chondrogenic differentiation, confirmed by the lack of collagen type II in the extracellular matrix (ECM) of ‎GF aggregates. Our data suggest that identification of gingival stem cells based solely on CD146 is not ‎sufficient to properly carry out translational research using gingival fibroblasts for novel therapeutic ‎methods of treating oral disease.‎