Transforming growth factor-beta1 (TGF-beta1) in dentine matrix. Ligand activation and receptor expression.

Transforming Growth Factor-beta (TGF-beta) and other members of this family of growth factors have been implicated in tooth development and dental tissue repair. This study aimed to investigate regulatory factors for TGF-beta1 in rabbit incisor dentine matrix and the expression of receptors for TGF-beta in dental tissues better to understand the control of its biological activity. Approximately half of the TGF-beta1 in dentine matrix was present in active form. TGF-beta1 was found in association with latency associated peptide (LAP), betaglycan and decorin in an isolated dentine matrix preparation. Immunohistochemistry showed strong staining for TGF-beta type I and II receptors in odontoblasts with more variable and weaker staining of other pulpal cells. Association of TGF-beta1 with betaglycan, decorin and LAP may regulate the availability and biological activity of this growth factor and influence its presentation to the TGF-beta type I and II receptors on odontoblasts. During dental tissue repair, such control processes will be important in regulating the biological effects of TGF-beta1 on cells of the dentine-pulp complex.