RESUMO
BACKGROUND: Tissue engineering using mesenchymal stem cells (MSCs) is a recent therapeutic modality that has several advantages. MSCs have high proliferation potential and may be manipulated to permit differentiation before being transplanted, suggesting they may be an ideal candidate for regenerative procedures. Precise identification of cells capable of regenerating the periodontium is valuable because no predictable regeneration procedure has yet been described. The purpose of this study is to determine the presence of MSCs in human gingival connective tissue and their morphologic and functional characteristics. METHODS: Gingival connective tissue samples were obtained from five healthy students. The samples were deepithelialized, leaving only connective tissue. The explants were minced and cultured on tissue culture dishes for 3 to 4 weeks, after which cells were characterized by flow cytometry. Differentiation into osteogenic, chondrogenic, and adipogenic lineages was induced and evaluated by culture staining. An immunoregulation assay was also performed. RESULTS: The results show that gingival tissue cells fulfill the minimal criteria proposed by the International Society for Cellular Therapy to be defined as MSCs. Cell characterization was consistently positive for CD90, CD105, CD73, CD44, and CD13 markers and negative for hematopoietic markers CD34, CD38, CD45, and CD54. We observed differentiation in positive staining of adipogenic, chondrogenic, and osteogenic lineages. Furthermore, gingival cells showed immunomodulative capacity. CONCLUSION: Gingival connective tissue could be a reservoir of MSCs that could be used in regenerative procedures based on tissue engineering.