[Human amniotic mesenchymal stem cells inhibit allogeneic lymphocyte proliferation and reduce the secretion of...

To investigate the effects of human amniotic mesenchymal stem cells (hAMSCs) on the function of lymphocytes in vitro.

Enzymatic digestion method was used to isolate and culture hAMSCs. Fluorophore-labeled mouse anti-human monoclonal antibodies were used to identify cell surface antigens with flow cytometry. The expressions of vimentin and stage specific embryonic antigen-4 (SSEA-4) were detected by immunofluorescence staining. Isolated lymphocytes were stimulated by concanavalin (ConA), and then 1 × 10⁴, 5 × 10⁴, 1 × 10⁵ hAMSCs were co-cultured with the ConA-treated lymphocytes. Lymphocyte proliferation was measured by CCK-8 assay and the supernatant level of IFN-γ was determined by ELISA.

ConA (5 μg/mL) could cause lymphocyte proliferation. hAMSCs inhibited lymphocyte proliferation induced by ConA in co-culture conditions, and with the increasing number of hAMSCs, the suppressing effect was more obvious. When the cells were cultured for 72 hours, CCK-8 assay showed that the number of lymphocytes treated with ConA alone was significantly higher than that of ConA-treated lymphocytes co-cultured with hAMSCs. The best inhibitory group 1 × 10(6) lymphocytes co-cultured with 1 × 10⁵ hAMSCs was selected to measure supernatant IFN-γ secretion by ELISA after 72 hours. The level of IFN-γ was significantly lower than that in the simple ConA-stimulated group.

HAMSCs could inhibit lymphocyte proliferation and reduce IFN-γ secretion induced by ConA in vitro.