[Effects of Prostaglandin E₂ Receptor 4 Agonist on the Expression of Stem Factors in Human CD34⁺ Cells]

To investigate the effect of prostaglandin E₂ recoptor 4 antagonist (EP₄A) on the self-renewal ability of human CD34⁺ cells and its mechamism.

The peripheral blood hematopoietic stem cell of 20 healthy donors received the G-CSF-mobilization were collected, then the human CD34⁺ cells were sorted out by MACS microbead kit. The human CD34⁺ cells were treated with DMSO (control group), EP₄A (EP₄A group) and EP₄A+EP₄A antagonist (EP₄A+EP₄A group) for 72 hours. The differential genes and pathways related with CD34⁺ cell stemness were detected by Thermogram and Pathway enrichment analysis. and then the expression levels of protein and gene (β-catenin, Nanog, Oct4, Sox2, Stat3, AKT, P38) were detected by qRT-PCR and Western blot respectively.

EP₄A could elevate the mRNA and protein expression of β-catenin, Nanog, Oct4, Sox2, in comparison with control group, however, mRNA and protein expression of STAT3, AKT, P38 were not changed. When human CD34⁺ cell were cultured with EP₄A+XAV939 it was found that the mRNA and protein expression of β-catenin was downregulated, moreover the mRNA and protein expression of Nanog, Oct4, Sox2 were reduced.

EP₄A can upregulate stemness factors-β-catenin, Nanog, Oct4 and Sox2 in human CD34⁺ cell in vitro, but not STAT3, AKT and P38.