MSC treatment reduced inflamed tissue damage and improved salivary gland function in NOD/Ltj mice. (A-C) Histology of the submandibular glands of NOD/Ltj mice in untreated, prevention, and treatment groups. Pretreated indicates 6 weeks for prevention and 16 weeks for treatment groups; and 2 weeks post, 2 weeks later with or without MSC infusion (8 weeks for prevention and 18 weeks for treatment groups). Yellow box area is magnified in the black box. In the prevention group (B), the infiltrating area in the submandibular glands was significantly smaller than control (P = .017, n = 6). In the treatment group (C), the infiltrating area was significantly reduced 2 weeks after MSC infusion (P = .009, n = 6). (D-E) The saliva flow rate of NOD/Ltj mice before and after MSC infusion. The saliva flow rate began to decrease at ∼ 6 weeks of age and declined rapidly at 7 and 8 weeks of age. *Six, 7, and 8 weeks versus 4 weeks in the untreated group (all P < .05); n = 6. In the prevention group (D), the saliva flow rate returned to baseline (4 weeks level) 2 weeks after BMMSC infusion. #P = .977 (n = 6). (E) The saliva flow rate in the treatment group increased 2 weeks after BMMSC infusion (P = .045, n = 6), whereas the untreated group remained at a lower level.