Due to immature development of the immune system, preterm infants are at increased risk of infections from vaccine-preventable diseases. But at the same time, premature vaccination may not induce a good immune response because of the incomplete development of the neonatal immune system, and may cause serious adverse reactions risk due to the poor immune tolerance, thus vaccination of preterm infants at the appropriate time is the key to reducing the risk of infectious disease and obtaining vaccine protection. At present, it is generally recommended that the gestational age and birth weight should be considered in the vaccination of preterm infants. The timing, type and even the immunization schedule of the vaccine should be differ from that of the full term infants. However, there is a lack of research results and data on immunization program in preterm infants in China, and there is still no provided universal guidelines for their vaccine immunization. This article aims to summarize the guidelines and clinical trials of vaccination of preterm infants in foreign countries, and to provide reference for the formulation and implementation of immunization strategies for preterm infants in China.

Objective To evaluate anti-HEV IgG and IgM diagnostic kits with sera from convalescent hepatitis E patients and to establish the quantification method of detecting anti-HEV lgG.Methods Detect 42 convalescent serum samples of over 6 months after onset of hepatitis E patients from Jiangsu province with anti-HEV IgM and IgG diagnostic kits. Select and mix the anti-HEV IgG positive sera which were confirmed by Western blot with ORF2 and ORF3 antigen. The mixed serum was calibrated with a WHO anti-HEV Ig standard. A series quantitative linear standard was made for quantitative detection of anti-HEV IgG in hepatitis E vaccine clinical trials phase Ⅲ. Results The positive rates of the anti-HEV IgG di-agnose kits of G, K, MP, Wantai were 71.4%, 78.6%, 92.9% and 100% respectively. The positive rates of G was lower than that of MP (χ~2 = 5.19, P<0.05) and obviously lower than Wantai (χ~2 = 11.76,P<0.01). The positive rates of K was also obviously lower than that of Wantai (χ~2 =7.96, P <0.01).The positive rates of the anti-HEV IgM diagnose kits of MP, G, X, Wantai, K were 21.4%, 7.1%,21.4%, 64.3%, 78.6% respectively. The positive rate of both K and Wantai were obviously higher than that of MP(χ~2 = 15.75 ,P<0.01 ; X2 = 27.43 ,P< 0.01). With the Western blot confirmation test, 30 and 18 sera were reactive to ORF2 and ORF3 antigen separately. The anti-HEV IgG concentration of HEV-D01 mixed by 13 samples was 57.94 U/ml by the calibration. Prepare seven 1.5-fold dilution series of quantita-tive linear standard for HEV vaccine clinical trials phase Ⅲ, concentration range from 0.077 to 0.877 U/ml. The quantitive values of high, medium and low concentrations quality control samples lay in the range of average ± 2s, and the CV of quantitative values were 16%, 16%, 12% respectively. Conclusion The quality of different anti-HEY IgM and IgG diagnose kits were different. This study had set up a set of anti-HEV IgG linear quantitative standard, which fit for detecting anti-HEV IgG antibodies quantitatively in HEVvaccine clinical trial phase Ⅲ.

Objective To evaluate the practicability of using CRISPR/Cas9 genome editing tech-nology for inhibition of hepatitis B virus ( HBV) replication. Methods Two sgRNA targeting sites were de-signed for the S region of HBV genome. The CRISPR/Cas9 expression plasmids specific for HBV were con-structed and then transfected into a cell line expressing HBV genome(HepG2-N10). The cytotoxicity of cells transfected with different expression plasmids were detected by MTT assay. The levels of hepatitis B surface antigen ( HBsAg ) were determined by using chemiluminescent immunoassay ( CLIA ) . The expression of HBV at mRNA level was analyzed by quantitative real-time PCR ( qRT-PCR) . The qPCR was performed for the detection of extracellular and intracellular HBV DNA. The next-generation sequencing ( NGS) Illumina MiSeq Platform was used to analyze HBV genome editing. Results No significant cytotoxic effects were de-tected in HepG2-N10 cells transfected with different expression plasmids. Compared with the cells carrying pCas-Guide-GFP-Scramble, the levels of HBsAg in the supernatants of transfected cell culture harboring pCas-Guide-GFP-G1 and pCas-Guide-GFP-G2 were decreased by 24. 2% (P<0. 05) and 16. 9% (P>0. 05), respectively. The levels of HBsAg in cells transfected with pCas-Guide-GFP-G1 and pCas-Guide-GFP-G2 were respectively decreased by 16. 4% (P>0. 05) and 32. 1% (P>0. 05) as compared with that of pCas-Guide-GFP-Scramble transfected group. The expression of HBV at mRNA level was inhibited as indica-ted by the results of qRT-PCR. Moreover, the levels of extracellular HBV DNA were respectively suppressed by 23% (P>0. 05) and 35% (P<0. 05), and the levels of intracellular HBV DNA were respectively sup-pressed by 7. 2% (P>0. 05) and 18% (P>0. 05). Different types of insertion/deletion mutation were de-tected in HBV genome by high-throughput sequencing. Conclusion HBV-specific CRISPR/Cas9 system could inhibit the expression of HBV gene and the replication of virus. Therefore, the CRISPR/Cas9 genome editing technology might be used as a potential tool for the treatment of persistent HBV infection.

Objective To evaluate the diagnostic value of detection of IgM antibodies to EV71-infection patients,and compared characterisation of RT-PCR,IgM capture ELISA and neutralization test.Methods Virus RNA,neutralization titer and IgM antibody in 115 EV71-infection patients were detected by EV71 real-time RT-PCR kit( EV71-PCR kit),neutralization test,and EV71 IgM-capture ELISA kit (EV71-IgM kit),respectively.Results Using EV71-IgM kit,the detection rate was 80.9％ (93/115,95％ CI:72.5-87.6) among the 115 EV71-infection patients,and was 2.6％ among the 228 healthy children.Simultaneously,sera collected after 1-2 day of disease onset showed an IgM positivity of 70.4％ (38/ 54).The positive rate of EV71-PCR among these patients was 82.6％ (95/115,95％ CI:74.4-89.0),so there was no statistically significant differences between it and EV71-IgM kit.In addition,the detection rate in EV71-infection patients could increase to 92.2％ by combined detection of EV71-PCR and EV71-IgM kit.Conclusion EV71-IgM kit was a rapid and valuable way for the early diagnosis of EV71 infection,and could significantly improve detection rate for EV71 infection by combining with EV71-PCR kit.

Intestinal microbiota plays an important role in the development of immune system,es-pecially in the formation of immune response. Immune response to vaccination varies with region and popula-tion,which may be related to the differences in intestinal microbiota. This review focused on the correlation between intestinal microbiota and immune response to vaccination in order to find a new way to enhance vac-cine-induced immune response. It was revealed that intestinal microbiota might be involved in the immune responses to vaccines against rotavirus, typhoid and polio. Although probiotics, prebiotics and synbiotics could not significantly enhance vaccine-induced immune response,they might have a beneficial effect on vac-cine by regulating intestinal microbiota.

An immunological surrogate endpoints is a vaccine-induced immune response (either humoral or cellular immune) that predicts protection against clinical endpoints (infection or disease), and can be used to evaluate vaccine efficacy in clinical vaccine trials. Compared with field efficacy trials observing clinical endpoints, immunological vaccine trials could reduce the sample size or shorten the duration of a trial, which promote the license and development of new candidate vaccines. For these reasons, establishing immunological surrogate endpoints is one of 14 Grand Challenges of Global Health of the National Institutes of Health (NIH) and the Bill and Melinda Gates Foundation. From two parts of definition and statistical methods for evaluation of surrogate endpoints, this review provides a more comprehensive description.
Biomarkers ; Clinical Trials as Topic ; Data Interpretation, Statistical ; Humans ; Research Design ; Treatment Outcome ; Vaccines ; administration & dosage ; immunology

Original antigenic sin may exist in the influenza virus infection or vaccination, which possibly reduces the protective efficacy in repeated influenza vaccination. This paper reviews the literature on the original antigenic sin and its influence in influenza vaccination, and interprets the possible mechanism of this phenomenon from the three aspects of influenza virus structure, humoral immunity and cellular immunity. A large number of studies have shown that original antigen sin has a negative impact on influenza vaccination, but the evidence disproveing this phenomenon also exist, so multi-center large-scale clinical trials should be conducted to provide evidence-based basis for reaearching whether original antigen sin exists and its effects. in order to provide reference for the development and update of noval influenza vaccines and its formulation of immunization strategies.

Objective The objective of this study was to investigate the epidemiological characteristics of disease caused by enterovirus type 71.Methods A total of 10 158 children aged between 6 and 35 months,were recruited from 7 sites where EV71 inactivated vaccine phase 3 clinical trial was carded out.All the subjects were followed up to one year to investigate the epidemiological characteristics of the disease caused by EV71.Results The accumulate incidence density of disease caused by EV71 was 15.17/1 000 person-year.Of all the cases,hand,foot and mouth disease (HFMD),herpangina,respiratory system diseases,digestive system diseases and other diseases accounted for 82.00％,2.67％,13.33％,1.33％ and 0.67％,respectively.The difference of the incidence density between boys and girls showed no statistical significance.Majority of the patients were between 12 and 23 months of age,which accounted for 58.67％ of the total patients.The differences of incidence density between different months of age were statistically significant (x2=7.789,P=0.020).The peak incidence density of disease caused by EV71 occurred from April to June.Nine cases showed severe symptoms or signs that accounted for 6.00％ of all the cases.All severe cases were identified as HFMD,of which 7 were boys and 2 were girls.The number of severe cases in different months of age appeared to be 1,7,and 1,all occurred between April and June.The median courses of HFMD cases and non-HFMD cases were 9 and 6 days,with difference statistically significant (Z=-4.000,P＜0.001).Median of excretion cycle for HFMD and non-HFMD cases were 9 and 11 days respectively.But with no statistically significant difference between the two.Conclusion Majority of the disease that caused by EV71 appeared as HFMD.Most of them were younger children and with seasonal variation.

OBJECTIVETo analyze the dynamic pattern and the distributive characteristics of neutralizing antibody against enterovirus 71 (EV-A71 ) in children aged 6-35 months in Jiangsu province from 2012 to 2014.

METHODSFrom March, 2012 to March, 2014, a total of 1 276 children aged between 6 and 35 months were regularly followed up on day 0, year 1 and year 2 for EV-A71 neutralizing antibody test based on the enterovirus surveillance system, with the method of reporting by their guardian or being visited in Ganyu Sheyang Taixing Donghai Pizhou and Baoying in Jiangsu province. At the same time, samples were taken from the suspected persons infected by enterovirus. The χ(2) test or variance analysis was used to compare the difference of the positive rates and the geometric mean titer(GMT) of EV-A71 neutralizing antibody in different subjects.

RESULTSIn 2 years follow-up, the positive rates of EV-A71 antibody increased as the growth of the age,and the positive rates on day 0, year 1 and year 2 were 22.57% (288/1 276), 37.72%(444/1 177) and 42.84%(422/985), respectively (χ(2) values were 39.33, 56.41, 32.25; P< 0.001).The GMTs were 9.95, 15.37 and 24.05, respectively (F values were 22.90,46.36,41.58;P<0.001). In 2 years, the annually new infection rates were 13.47%(158/1 173) and 20.73%(192/926),respectively, and the annually decay rates of EV-A71 antibody were 2.81%(33/1 173) and 8.10%(75/926).

CONCLUSIONSIn 2012 to 2014, the positive rates and the GMTs of EV-A71 antibody of children increased as the growth of the age in Jiangsu. The higher annually new infection rate was in children aged 3 to 4 years. The EV-A71 neutralizing antibody level could maintain at least two years after natural infection.

Antibodies, Neutralizing ; blood ; Antibodies, Viral ; blood ; Child, Preschool ; China ; epidemiology ; Enterovirus A, Human ; Enterovirus Infections ; blood ; Humans ; Infant ; Seroepidemiologic Studies

Objective: To establish a rapid and sensitive isothermal amplification assay for the detection of human Adenovirus. Methods: Primers and probe used for recombinase polymerase amplification(RPA)were designed based on the conserved region of the adenoviruses hexon gene. After optimizing the reaction temperature and times, the products of RPA were detected by capillary electrophoresis and lateral flow dipstick(LFD). Sensitivity and specicity of the assay were evaluated. The diagnostic value of the RPA-LFD assay was verified using clinical samples which were simultaneously tested by real time PCR assay. Results: The analytical sensitivity of RPA-LFD assay was 2 copies DNA molecules per reaction and no cross reaction with other pathogens was observed. Compared with real-time PCR assay, the sensitivity, and specificity of the present assay were all 100%. Conclusions The RPA-LFD assay developed in this study has the characteristics of high specificity, sensitivity, rapid and no requirement of expensive equipment which provided a new tool for rapid detection of human adenovirus.