Evaluation of Immunogenicity of Alginate Encapsulated Human Wharton's Jelly-Derived Mesenchymal Stem Cells in the Peritoneal Cavity of Rat

Background: Human Wharton's Jelly-derived Mesenchymal Stem Cells (hWJ-MSCs) have immunosuppressive and anti-inflammatory properties. As such,
they exhibit an attractive therapeutic option for autoimmune disorders. Microencapsulation provides adequate protection against immune destruction of
transplanted cells. We aimed to investigate the cellular and humoral immune responses in the host rats transplanted with alginate microencapsulated hWJMSCs
in their peritoneal cavities.
Methods: hWJ-MSCs were microencapsulated in alginate microspheres and were transplanted intraperitoneally to rats. After 30 days, for the
evaluation of rats' cellular and humoral immunity against hWJ-MSCs, the spleen mononuclear cells of rats were stained with CFSE and co-cultured
with hWJ-MSCs for 3 days. Then the proliferation of spleen cells against hWJ-MSC was evaluated by flow cytometry, and Interferon-gamma (IFN-γ)
secretion was measured by ELISA. For evaluating humoral immunity, the serum of different rat groups was incubated with hWJ-MSCs, and serummediated
cytotoxicity was measured by MTT assay and antibody binding by cell-based ELISA.
Results: There were no differences between the spleen mononuclear cells proliferation, secretion of IFN-γ, serum-mediated cytotoxicity, and anti-WJMSCs
antibodies in rats transplanted with encapsulated and non-encapsulated hWJ-MSCs. Encapsulated and non-encapsulated hWJ-MSCs did not
stimulate the immune system in rats at the same time.
Conclusion: We suggest using a 3D culture for proliferation and having a more favorable function in the transplantation of these hWJ-MSCs.