In vitro immunomodulatory effects of microencapsulated umbilical cord Wharton jelly-derived mesenchymal stem cells in primary Sjögren's syndrome.

OBJECTIVE Human umbilical cord Wharton jelly-derived mesenchymal stem cells (hUCMS) are easy to retrieve in bulk. They may interact with immune cells by either cell contact or soluble factors. Little evidence is currently available on potential therapeutic application of hUCMS to systemic autoimmune disorders such as primary SS (pSS). We have recently developed an endotoxin-free alginate gel that can be used to microencapsulate different cell types for graft into non-immunosuppressed hosts. We aimed to assess the in vitro effects of IFN-γ-pretreated microencapsulated (CpS)-hUCMS on T cells of pSS. METHODS Ten pSS patients and 10 healthy donors were selected. Peripheral blood mononuclear cells (PBMCs) were obtained from venous blood to establish co-cultures with CpS-hUCMS. Lymphocyte proliferation and phenotypic analysis was performed by flow cytometry and real-time PCR on IFN-γ-pretreated hUCMS was performed before PBMCs co-culture. RESULTS We found that CpS-hUCMS suppress pSS T cell proliferation and restore the Treg/Th17 ratio, thereby possibly positively impacting the pSS disease process. CONCLUSION We have developed a new biohybrid drug delivery system that now waits for clinical application in autoimmune diseases, including pSS.