Stem cells  from exfoliated  deciduous  teeth alleviate hyposalivation caused by Sjögren syndrome.

ABSTRACT

OBJECTIVES: To evaluate the effect of stem cells  from  exfoliated  deciduous  teeth on the hyposalivation caused by Sjögren syndrome (SS) and investigate the mechanism. METHODS: Stem cells were injected into the tail veins of non-obese diabetic mice, the animal model of SS. The saliva flow was measured after pilocarpine intraperitoneal injection. Apoptosis and autophagy were evaluated by TUNEL and Western blot. Lymphocyte proportions were detected by flow cytometer. RESULTS: Fluid secretion was decreased in 21-week-old mice. Stem cell treatment increased fluid secretion, alleviated inflammation in the submandibular glands and reduced inflammatory cytokine levels in the serum, submandibular glands and saliva. Stem cells decreased the apoptotic cell number and the expressions of ATG5 and Beclin-1 in the submandibular glands. Stem cells have no effect on other organs. Furthermore, the infused stem cells migrated to the spleen and liver, not the submandibular gland. Stem cells directed T cells towards Treg cells and suppressed Th1 and Tfh cells in spleen lymphocytes. CONCLUSION: Stem cells  from  exfoliated  deciduous  teeth alleviate the hyposalivation caused by SS via decreasing the inflammatory cytokines, regulating the inflammatory microenvironment and decreasing the apoptosis and autophagy. The stem cells regulated in T-cell differentiation are involved in the immunomodulatory effects.