Promotability and mechanism of IL-27 on differentiation and maturation of dendritic cells derived from human periperal blood mononuclear cells

Objective: To observe the effect and mechanism of IL-27 on the morphology and function of human peripheral blood mononuclear cell(PBMC)-derived dendritic cells(DCs).Methods: PBMCs were purified from peripheral blood of healthy adults and incubated with granulocyte/macrophage colony stimulating factor(GM-CSF) and interleukin-4(IL-4) for 7 days.The DCs were divided into four groups by different stimulatory factors at the fifth day: a negative group,a positive group(TNF-α: 20 ng/ml),IL-27 group(20 ng/ml) and TNF-α+IL-27 group(co-cytokines group,10 ng/ml TNF-α+ IL-27 10 ng/ml).The morphology of DCs was observed under an inverted microscope at the 7th day.The expressions of CD1a and CD83,CD80 and CD86 on DCs were analyzed by flow cytometry.The mRNA levels of chemokine receptors of CCR5 and CCR7 on DCs were analyzed by RT-PCR.The stimulatory ability of DCs on proliferation of allogeneic T cells was detected by MLR.The proteins of P-STAT1 and P-STAT3 were detected by Western blotting.Results: DCs from the IL-27 group and TNF-α + IL-27 group had a typical morphological characteristic of mature DCs after 7 days.The expressions of co-stimulatory molecules of CD1a and CD83([35.75±4.10]%,[52.49±2.65]% vs [23.29±4.49]%,P0.05),CD80 and CD86([39.06±1.61]%,[54.10±0.46]% vs [22.66±3.20]%,P0.05),chemokine receptor of CCR7(3.98±0.09,4.75±0.11 vs 3.09±0.18,P0.05) and the proteins of P-STAT1/STAT3 on DCs were up-regulated both in the IL-27 group and co-cytokines group compared with the negative group,while chemokine receptor of CCR5(0.99±0.03,0.61±0.02 vs 1.23±0.26,P0.05) was down-regulated.The proliferation of T cells was improved by DCs from the IL-27 group and TNF-α + IL-27 group.The tendency was especially obvious in the co-cytokines group.Conclusion: IL-27 can directly or synergically enhance the differentiation,maturation and antigen presentation ability of DCs with TNF-α.The mechanism might relate to the activation of P-STAT1/STAT3 signal transduction pathway.