Abstract:

BACKGROUND: We know little about the immune regulatory effect of adipose-derived mesenchymal stem cells.
OBJECTIVE: To investigate the influence of adult adipose-derived mesenchymal stem cells on lymphocyte proliferation, cells subsets and the level of cell factors in vitro, in order to understand the immune regulatory effect.
METHODS: Adipose-derived mesenchymal stem cells were isolated from adult adipose tissue. The phenotype was identified with the flow cytometry. Adipose-derived mesenchymal stem cells were induced into osteoblasts and myocardial cells, respectively, and identified with the immunocytochemistry staining. The human peripheral blood lymphocytes were separated and cultured with adipose-derived mesenchymal stem cells according to different concentrations (1:1, 1:10, 1:100), and added the plant haemagglutinin for simulation. The control group was set up, and after 3 days, the culture fluid was collected.
RESULTS AND CONCLUSION: The absorbance value of adipose-derived mesenchymal stem cells in the treatment group after co-cultured with lymphocytes with three different concentrations was significantly lower than that in the control group, and 1:1 concentration had the lowest absorbance value (P < 0.05); the proportion of CD4⁺CD25⁺ Tregs in the treatment groups was significantly higher than that in the control group, and highest in the 1:1 concentration group. The cell factors of interleukin-2, interleukin-4 and γ-interferon were obviously reduced in the treatment groups, while the interleukin-10 level was increased, and showed a certain concentration-dependent manner (P < 0.05). Adipose-derived mesenchymal stem cells can significantly suppress the proliferation of lymphocyte in vitro. The inhibition effect may relate with the increasing of CD4⁺CD25⁺ Tregs subsets, and relate with the changing of cytokine secretion of lymphocyte.