KIT and Sjogren syndrome: Studies indicate that exosomes derived from labial mesenchymal stem cells can treat Sjögren's syndrome by mediating miRNA‐125b targeting PRDM1 and inhibiting plasma cells (Xing et al. 2022); exosomes from hypoxia‐preconditioned urinary stem cells can activate the Wnt3a/GSK3β pathway, thereby inhibiting the expression of α‐SMA and c‐Kit, and effectively repair radiation‐induced salivary gland damage (Xiao et al. 2022).