New Therapeutic Strategy for Regenerating Periodontal Tissue Based on the Combination of Amelogenin and Reapplications of Existing Grp78 Inducer

The present study aims to develop a highly safe regenerative therapy that effectively induces periodontal tissue regeneration by targeting amelogenin and its newly associated molecule, glucose-regulated protein 78 (Grp78). The enamel matrix derivative (Emdogain® Gel, Straumann) is currently the only bioregeneration tool in use that is approved by the Japanese Ministry of Health, Labour and Welfare. However, in addition to the safety issues that exist owing to it being a foreign protein, a unified opinion on its mechanism of action at the signal transduction level remains unclear. Previously, our laboratory was the first to report the identification of a new amelogenin-associated molecule, Grp78, in osteoblasts. This association was later shown to promote the migration of periodontal ligament stem cells (PDLSCs), which play critical role in periodontal regeneration. Based on these results, we aim to establish the molecular basis for periodontal tissue regeneration via the combined use of recombinant amelogenin and inducers of Grp78 which could be applied by reapplication of existing drugs (drug repositioning).