Potential regeneration capacity of periodontal ligament with autocrine production of transforming growth factor-beta 1 and its receptors

Background: Transforming growth factor-beta1 (TGF-[beta]1) has been extensively studied and reported to be widely expressed in tissues during dentinogenesis and the supporting periodontal tissues. Aims and Objectives: To determine the distribution of TGF-[beta]1 and its receptors in periodontal cells, and to gain insight into the potential actions of TGF-[BETA]1 in periodontal tissues. Materials and Methods: Rat periodontal cells were collected from the animal alveolar bone, molar teeth and its surrounding gingivae by cell-explant technique, and primarily characterised and cultured. Cell lysates were detected at the cellular and mRNA levels using in situ hybridization, RT-PCR and Western immunoblots. Results: The mRNA for TGF-[beta]1 was highly expressed in cementoblasts, moderate in osteoblasts and weak in gingival fibroblasts, while TGF-[beta]1 and its receptors (TGFPR-II and TGF-[beta]R-III) were detected in all periodontal cells. At the protein levels, TGF-[beta]1 and TGF-[beta]R-II were expressed in all periodontal cell types. Conclusion: This study suggests that TGF-[beta]1, TGF-[beta]R-II and TGF-[beta]R-III are produced locally by periodontal cells and play a role in the developing periodontium through regulatory autocrine manners. This would implicate the regeneration capacity in PDL. Key Words: in situ hybridization; periodontal cells; RT-PCR; TGF [beta]i and TGF [beta] receptors; western blot analysis