Effects Of IL-27 On HPMSCs Adhesion,Proliferation,Migration And Immunoregulatory Function

Objective:To investigate whether transplanted human placenta derived mesenchymal stem cells(hPMSCs)could regulate the serum level of IL-27 and the percent of Thl,Th2,CD4+IL-10+T cell subsets in GVHD model.And futher study the effect of IL-27 on hPMSCs adhesion,proliferation and migration.Finally the effect of IL-27 on hPMSCs ability to induce Th1,Th2 and CD4+IL-10+T cell subsets in vitro were also investigated.Methods:To induce humanized murine models of GVHD,non-obese diabetic/severe combined immunodeficient(NOD/SCID)mice were been used.Then hPMSCs were transfused intravenously to treat the humanized murine models of GVHD.The mice were sacrificed after hPMSCs treatment for 7 days and 14 days respectively.The concentration of human IFN-?,IL-4,IL-10 and IL-27 were determined in mice serum by using Cytometric Bead Array(CBA)and ELISA respectively.Hematoxylin and eosin(HE)staining was used to observe the morphological changes of lung and kidney in GVHD mice before and after treatment by hPMSCs.Flow cytometry(FCM)was used to detect the changes of Th1(CD4+IFN-?+T),Th2(CD4+IL-4+T)and CD4+IL-10+T cells in spleen and liver cells in mice.The expression of IL-27R? in hPMSCs was detected by reverse-transcription-polymerase chain reaction(RT-PCR),gegetic sequencing and western blot.The effect of IL-27 on hPMSCs adhesion,proliferration and migration was analysed by real-time cell analysis(RTCA).And the effect of IL-27 on hPMSCs ability to induce Th1,Th2 and CD4+IL-10+T cells from PBMC was detected by FCM.Beisides the expression of programmed death ligand 1(PDL1)on hPMSCs was analysed by FCM.Results:1.hPMSCs were able to alleviate the clinical symptoms of humanized murine models of GVHD(1)Humanized murine models of GVHD was successfully constructed.(2)Compared PBS control group,in hPMSCs treatment group the weight of mice was gradually restored(P<0.001),the clinical score was significantly reduced(P<0.001),and the survival time was remarkably prolonged(P<0.001).Histologically,the pathological changes of lung and kidney in hPMSCs treatment group were improved compared with PBS control group.(3)The FCM results showed that after hPMSCs treatment for 7 days the Th2 and CD4+IL-10+T cells were significantly increased,while the Thl cells was remarkably decreased in liver and spleen compared with PBS control group.Besides the hPMSCs regulatory effects for the three subsets were greater for 14 days than 7 days(P<0.01).(4)The serum levels of IL-27,IFN-y,IL-4 and IL-10 in GVHD model was increased.And the levels of IL-4 and IL-10 in serum was increased with hPMSCs treatment for 7 days comapred with PBS control group.However,the levels of IL-27 and IFN-y were decreased.After treating by hPMSCs for 14 days,the levels of these cytokines were futher changed.And the levels of IL-27 had no relationship with IFN-y,IL-4 and IL-10.2.Effects of IL-27 on hPMSCs adhesion,proliferation,migration and immunoregulatory function(1)The results of RT-PCR,Westen blot,FCM and gegetic sequencing showed that IL-27a was expressed in hPMSCs.(2)IL-27 at 30 ng/ml inhibited hPMSCs adherence and proliferation,while the migration of hPMSCs was promoted in response to IL-27 at doses of 20 or 30 ng/ml.(3)IL-27 promoted regulatory effects of hPMSCs through its capacity to enhance Th2 and suppress Th1 subset differentiation from T cells activated by phytohemagglutinin(PHA)in PBMC.IL-27 also enhanced the ability of hPMSCs to secrete IL-10 from CD4+T cells.(4)IL-27 also enhanced the ability of hPMSCs to expression levels of the programed death ligand 1(PDL1)in hPMSCs via the JAK/STAT1 signaling pathway.Conclusion:1.hPMSCs were able to alleviate the clinical symptoms of GVHD mice through shifting Th1/Th2 imbalance,inducing CD4+IL-10+T cells and decreasing the serum level of IL-27.2.IL-27 has significant modulatory effects on adherence,proliferation and migration of hPMSCs.IL-27 increased PDL1 expression levels in hPMSCs via the JAK/STAT1 pathway,which then enhanced the regulatory effect of hPMSCs in Th1 and Th2 cell differentiation and IL-10 secretion from CD4+T cells.