Effects of interaction between dengue virus type 2-infected HUVECs and human CD4+T cells on the expression of adhesion molecules and immunosuppressive factors / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the effects of interaction between human umbilical vein endothelial cells (HUVECs) which were infected with dengue virus type 2 (DENV-2) and CD4+T cells on the expression of ICAM-1 (intercellular adhesion molecule 1),VCAM-1 (vascular cell adhesion molecule 1),IL-10 and TGF-β1 at mRNA level for further understanding the immunological mechanism of DENV infection.Methods HUVECs were treated with CYM-5442,a selective agonist for sphingosine-1-phosphate receptor 1 (S1P1),for 24 hours and then infected with 103 TCID50 (50% tissue culture infective dose) of DENV-2 before co-culturing with CD4+T cells.Changes in the expression of NS1 (DENV-2 nonstructural protein),SPHK1 (sphingosine kinase 1,phosphorylating sphingosine to S1P),ICAM-1,VCAM-1,IL-10 and TGF-β1 at mRNA level were detected by real-time PCR after 4,8,12,24,48 and 72 hours of co-culturing.Results There was a certain timeliness in the expression of NS1 at mRNA level after infecting HUVECs with DENV-2 and the expression reached a peak at 24 h.Treating HUVECs with or without CYM-5442 had no significant influence on the expression of DENV-2 NS1 at mRNA level.The expression of SPHK1 at mRNA level was significantly increased after treating HUVECs with CYM-5442 and DENV-2 (P<0.05).Compared with DENV-2-infected or untreated HUVECs,Co-culturing DENV-2-infected HUVECs with CD4+T cells increased the expression of ICAM-1 and VCAM-1 in HUVECs at mRNA level (P<0.01) as well as the expression of IL-10 in CD4+T cells at mRNA level (P<0.05),but had no significant influence on the expression of TGF-β1 in CD4+T cells at mRNA level.Conclusion This study shows that DENV-2 can replicate and proliferate in HUVECs,but CD4+T cells inhibit the replication and proliferation.CD4+T cells play an important role in promoting the expression of VCAM-1 and ICAM-1 in DENV-2-infected HUVECs at mRNA level,activating HUVECs and increasing inflammation,which may be associated with increased vascular permeability induced by DENV-2 infection.Co-culturing CD4+T cells with DENV-2-infected HUVECs promotes the expression of IL-10 in CD4+T cells at mRNA level,but has no significant effect on TGF-β1.