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Objective:To investigate the effects of macrophage migration inhibitory factor (MIF) on AMPK/ERK/mTOR autophagy signaling pathway in primary human umbilical vein endothelial cells (HUVEC) after dengue virus type 2 (DENV2) infection.Methods:The virulence of DENV2 to C6/36 cells was assessed with 50% tissue culture infectious dose (TCID 50). NS1 gene fragments in DENV2-infected HUVEC were detected by RT-PCR. Transmission electron microscopy was used to detect autophagosomes. Western blot was performed to detect the effects of DENV2 infection on the expression of autophagy-related protein LC3-Ⅱ and MIF in HUVEC. The correction of MIF with LC3-Ⅱ was then analyzed. HUVEC were pretreated with MIF inhibitor (ISO-1) or pathway inhibitor (Compound C or U0126), and then the changes in the expression of MIF, adenosine 5′-monophosphate-activated protein kinase (AMPK) pathway-related proteins and LC3-Ⅱ after DENV2 infection were detected by Western blot to reveal the correlation between MIF and AMPK autophagy pathway. Results:The TCID 50 to C6/36 cells was 10 -9.09/ml in this experiment. NS1 gene fragments were detected in DENV2-infected HUVEC. Autophagosomes or autophagolysosomes were observed in the infected HUVEC and there were differences in autophagy induced by different doses of DENV2. The mRNA levels of MIF and LC3-Ⅱ in HUVEC were positively correlated after DENV2 infection. MIF inhibitor affected AMPK, ERK and LC3-Ⅱ levels, but had no significant influence on MIF expression at protein level. Conclusions:MIF could affect autophagy through regulating the AMPK/ERK/mTOR signaling pathway in HUVEC during DENV2 infection.
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Objective @#To evaluate the immune effects of inactivated H7N9 influenza vaccine.@*Methods @#We searched several common databases（The Cochrane Library,PubMed,China Biology Medicine disc,China National Knowledge Infrastructure,etc.）for research articles about immune effects of H7N9 influenza vaccine published from the time the database built to July 10th of 2018,using H7N9 and vaccine as keywords. After screening the articles according to the inclusion and exclusion criteria,we assessed the quality of the studies and then employed seroconversion rate（SCR）as an outcome indicator to analyze the immune effects of different doses and adjuvants.@*Results @#We recruited 5 articles on inactivated H7N9 influenza vaccine from 1 679 articles. The sample size was 2 579. The results of the meta-analysis showed that the rate difference（RD）values of SCR in each dose group after the first dose ranged from 1% to 10%,which indicated a poor protective effect;after the second dose of immunization,the RD values of SCR in the vaccines without adjuvants ranged from 13% to 19%,which was not effective enough;the RD values of SCR in the vaccines with adjuvants ranged from 62% to 69%,which met the licensing criteria for influenza vaccine;better results could be achieved when immunized with two doses of vaccines with adjuvants（ RR=1.19,95%CI：1.02-1.39）;vaccines with AS03 or MF59 at the lowest dose of 3.75 μg had the same immune effects as ones at a dose of 15 μg;vaccines with AS03（RD=89%,95%CI：85%-93%）were superior to those with MF59（RD=42%,95%CI：9%- 75%）.@*Conclusion @#Inactivated H7N9 influenza vaccines could achieve good immune effects when inoculated two doses with adjuvants,and the minimum effective dose was 3.75 μg.