Prevention of irradiation-induced damage to salivary glands by local delivery of adipose-derived stem cells via hyaluronic acid-based hydrogels

Abstract Most patients with head and neck cancer experience salivary gland dysfunction after chemo- and radiotherapies. There is currently no available treatment for this condition. Intervention with stem cell therapy has emerged as a promising approach. Although some progress has been made with systemic delivery of stem cells, it remains challenging to deliver a sufficient number of stem cells to the damaged tissue. Furthermore, local delivery of stem cells involves frequent cell loss. Herein, we evaluated the ability of adipose-derived stem cells (ASCs) with or without hydrogel to prevent salivary gland damage. Salivary gland cells were isolated from irradiated mouse submandibular glands. These cells exhibited higher expression levels of amylase, mucin, and aquaporin-5 when co-cultured with ASCs. Local delivery of ASCs into the salivary gland, using in situ-forming hyaluronic acid-based hydrogel (HA gel) as a carrier, revealed that ASCs remained at the injection site for a longer duration, compared with ASCs that were injected without HA gel. The salivary gland exhibited better function and morphology when ASCs were injected using an HA gel. In conclusion, retention of locally delivered ASCs by HA gels can enhance the paracrine effect of ASCs, thereby preventing irradiation-induced damage to the salivary gland and subsequent dysfunction.