Bone Abstracts

Numerous studies have reported beneficial effects of multipotent mesenchymal stem cells (MSCs) in tissue repair and regeneration. These multipotent cells can be isolated from many different adult tissues and give rise to different cell lineages. The most well-characterized source for adult stem cells is still adult bone marrow, however in the past decade, subpopulations of stem cells have been isolated from dental tissues. Dental pulp has been identified as a promising source of MSCs: thus dental pulp stem cells (DPSCs) are capable of self-renewal and multilineage differentiation. Dental follicle stem cells (DFSCs) are either more undifferentiated than DPSCs and would have alternative applications in bone and periodontal tissue engineering. In this study DFSCs were isolated from tooth buds of healthy pediatrics patients and they showed ≥95% expression of stemness makers (CD73, CD90, CD146, CD44, CD105, and HLA-I) while were negative for CD45. Moreover DFSCs differentiated into osteoblast-like cells, produced mineralized matrix nodules and expressed typical osteoblastic markers. Then, DFSCs were characterized for the expression of adhesion molecules integrins and cadherins, in basal and osteoinductive conditions. Our preIiminary data showed that, DFSCs express Integrins alpha V, beta 3, alpha 5 and beta 1 in basal undifferentiated conditions; after 1 week of osteogenic trigger, the expression of alpha V, beta 3 and alpha 5 increased, while beta 1 decreased. DFSCs were also tested for the expression of Cadherins, and we found N-Cadherin to be very high expressed in basal conditions, while E-Cadherin was low expressed and P-Cadherin very poor expressed. Furthermore N-caderin expression increased during the first step of osteogenic differentiation, while decreased at the later times. Such adhesion molecules regulate stem cell maintenance, division and expansion and are involved in cell–cell and cell–matrix interaction. The homing and engraftment of MSCs, in the host tissues are important tools of the regenerative medicine and require cells to interact and recognize each others. Surface molecules as integrins and cadherins could be important key regulators of the differentiation processes; therefore further insights in this field will contribute to the successful generation or repair of damaged tissues.