OP061: Adipose tissue-derived mesenchymal stem cells for regeneration of irradiation-induced salivary gland damage

Abstract

Cell-based therapy has been reported to repair or restore damaged salivary gland (SG) tissues after irradiation. This study was aimed at determining whether systemic administration of human adipose-derived mesenchymal stem cells (hAdMSCs) could ameliorate radiation-induced SG damage following irradiation. External irradiation at a dose of 15 Gy was administered to neck fields of C3H mice. Mice were administered with hAdMSCs through the tail vein immediately after irradiation, and this infusion was repeated once a week for three consecutive weeks. The administration of hAdMSCs had improved SFR at 12 weeks after irradiation. hAdMSC-transplanted SGs showed fewer damaged and atrophied acinar cells compared with the irradiated untreated group. TUNEL and PCNA assays revealed fewer apoptotic cells and increased proliferative indices in the hAdMSC group compared with the irradiated group. The injected hAdMSCs were detected in the transplanted SGs 4 weeks after transplantation. Transdifferentiation of hAdMSCs into acinar or ductal cells in vivo was also observed. This study suggests that hAdMSCs have the potential for protection against irradiation-induced cell loss as well as for transdifferentiation into salivary epithelial cells. hAdMSCs could be a candidate for cell-based therapy for restoration of radiation-induced SG damage.