On Regulatory Mechanisms Of Inflammatory Cytokines And Dendritic Cell Of HFMD Infected With Intestinal Virus EV71

Background:Enterovirus 71(EV71)was the main pathogen of hand,foot and mouth disease(HFMD)in children.HFMD was acute and rapid progression disease pathway,but severe patients were mostly associated with serious complications such as meningitis and neurogenic pulmonary edema.Studies displayed that the disorder of patients immune system caused by the infection of EV71 was important.And dendritic cells(DC)infected by EV71 led to change of the cytokine level.The present experiment adopted vitro model of DC infected by EV71 in order to research dendritic cells maturation and the cytokines release.It couldn’t reflect the real change of CD80,CD83,CD86 percentage in the peripheral blood DC of the HFMD infected by EV71.The study mainly analyzed the change of CD80,CD83,CD86 percentage in the peripheral blood,the activated status of MAPK signaling pathways in DC and the level of cytokine in order to provide early diagnosis,prevention and treatment of serious HFMD infected by EV71.Objective:To study maturation,apoptosis,signal pathway and inflammato-ry cytokines of dendritic cell when infected with intestinal virus EV71.Methods:Diagnosed patients were divided into three groups according to the degree of infection and clinical analysis:the control group(n=20),the mild group(n=20)and the severe one(n=20).DC of each group was separated.And then the surface markers,activation of MAPK signaling pathway and the cell culture supernatants of infla-mmatory cytokine levels were detected.Results: 1.Clinical information analyzed that: In 40 cases of EV71 infection cases,male to female ratio was 1.11:1(21/19),age range for 7 months to 6 years old,the average age of 1.84±1.10 years,EV71 infection is given priority to with children under the age of 3,85.0%(34/40)of the patients with EV71 infection.There was significant difference of WBC,Neu(%),CK-MB,CRP,GLU,temperature level between mild and severe cases(P<0.05).As the deepening degree of infection,levels of AST,CK,LDH and HBDH were rising,but there was no significant difference(P>0.05).2.Flow cytometry(FCM)technology showed that: As the deepening degree of infection,levels of mature cell surface markers were rising.The mean levels of CD80 in control group,mild group and severe group were 0.96±0.83%,1.11±0.80 and 1.64±0.88%,and CD83 were 0.82±0.55%,1.41±0.63% and 2.04±1.35%,respectively.There was significant difference of CD83 level among each two of the groups(P<0.05).However only severe group and control group had significant difference about CD80 level(P<0.05).Levels of CD11 c and CD86 were increasing with the deepening degree of infection,but there was no significant difference among each two of the groups.3.Western blot appeared that: The ratios of p-p38 MAPK,p-JNK and p-ERK1/2 protein levels to corresponding to GAPDH were 0.84±0.15%,0.12±0.13% and 0.45±0.15% in severe group,respectively.Those were 0.55±0.19%,0.11±0.21% and 0.28±0.26% In mild group,respectively.And those were 0.06±0.01%,0.02±0.01% and 0.04±0.02% in control group.The ratios of p-p38 MAPK,p-JNK and p-ERK1/2 protein levels to GAPDH had significant difference among each two of the groups(P<0.05).And with the deepening degree of infection,levels of p-p38 MAPK,p-JNK and p-ERK1/2 protein were rising.4.ELISA showed that:The serum levels of IL-6 in control group,mild group and severe group were 7.88±2.12,12.86±2.86 and 16.89±3.20 ng/L,IL-12/P70 were 23.95±8.39,26.44±8.16 and 29.80±13.30 ng/L,and TNFα were 137.63±23.50,245.41±54.07,and 212.54±62.08 ng/L respectively.There was significant difference of IL-6 and TNFα level among each two of the groups(P<0.05).But thelevel of IL-12/P70 was no significant difference among each two of the groups.Conclusion:The level of WBC,Neu(%),CK-MB,CRP,GLU,body temperaturewas used as a early warning indexes in severe patients of EV71 infection.As the deepening degree of infection,levels of mature cell surface markers were rising,especially in CD83 and CD80.So we estimated that EV71 infection played an obvious role in promoting mature of DC.The results showed that the activation of MAPK signaling pathway strengthened gradually,the expression of cytokines increased significantly.In conclusion,EV71 infection can promote dendritic cell maturation and cytokine secretion.