Regulatory Effect of Exosomes Derived from Human Umbiilcal Cord Mesenchymal Stem Cells on Treg and TH17 Cells / 中国实验血液学杂志

ABSTRACT

OBJECTIVE@#To investigate the effects of exosomes from human umbilical cord mesenchymal stem cells on the development of Treg and TH17 cells.@*METHODS@#Exosomes from the serum-free-culture supernatants of hUC-MSC were harvested by ultracentrifugation. The electron microscopy, nanoparticle tracking analysis and western blot were used to identify the hUC-MSC-exosomes, such as the morphology, the paticle chameter, and the protein content. The PBMC stimulated with anti-CD3/CD28 were incubated with the exosomes for five days, and then the percentage changes of Treg and TH17 cells were analyzed by using flow cytometry.@*RESULTS@#The hUC MSC-derived exosomes were saucer-like in morphology the averge diameter was approximately 142 nm. They were identified as positive for CD9 and CD63. Flow cytometry showed that the proportion of CD4CD25Foxp3 Treg cells in the PBMC were significantly higher, but the proportion of CD4IL17A T cells in the hUC-MSC-exosome group was obviously lower than that in the group without the hUC-MSC-exosom (control group) (P<0.05).@*CONCLUSION@#The hUC-MSC-exosomes have an immunomodulatory effect on T cells in vitro by increasing the ratio of Treg and reducing the ratio of TH17 cells, expecting the hUC-MSC-exosom as a novel cell-free target for immunotherapy.