Effects of enamel matrix derivative and transforming growth factor-β1 on human osteoblastic cells

Cells were obtained from alveolar bone of three adult patients using enzymatic digestion. Effects of EMD, TGF-β1, or a combination of both were analyzed on cell proliferation, bone sialoprotein (BSP), osteopontin (OPN) and alkaline phosphatase (ALP) immunodetection, total protein synthesis, ALP activity and bone-like nodule formation.All treatments significantly increased cell proliferation compared to the control group at 24 h and 4 days. At day 7, EMD group showed higher cell proliferation compared to TGF-β1, EMD + TGF-β1 and the control group. OPN was detected in the majority of the cells for all groups, whereas fluorescence intensities for ALP labeling were greater in the control than in treated groups; BSP was not detected in all groups. All treatments decreased ALP levels at 7 and 14 days and bone-like nodule formation at 21 days compared to the control group.The exposure of human osteoblastic cells to EMD, TGF-β1 and the combination of factors in vitro supports the development of a less differentiated phenotype, with enhanced proliferative activity and total cell number, and reduced ALP activity levels and matrix mineralization.Periodontal regeneration is a complex series of cell and tissue events that include cell adhesion, migration, and extracellular matrix (ECM) protein synthesis and secretion. Phenotypic expression depends on cell interactions with ECM proteins, which regulate cell signaling events and ultimately gene expression[1]. The ECM proteins are, therefore, key factors that influence the regenerative capacity[2]. However, to date, it remains undefined which factors would determine the maximum regenerative capacity.Enamel matrix derivative (EMD) has been used in various clinical applications aiming to promote periodontal tissue regeneration. The rationale for such application is based on the expression of enamel matrix proteins during the initial phases of root formation, which has been associated with cementoblast differentiation[3,4]. In additio