Balb/c mice were immunized by intraperitoneal iniection of group A erythrocytes. Immunized spleen cells were fused with Sp2/0 murine myeloma cells from the solid tumour. After 10～15 days of incubation at 37℃ CO_2, the supernatants were screened for the agglutinabal antibodies. Three hybridoma cell lines secreting high titer and specific monoclonal anti-A antibodies were established.These hybridoma cells have the ability of constant seceting antibodies which belong to the IgM class. The specificity monocloal anti-A sera was the same as the human anti-A sera.

Preparation of maternal strain A/PR/8/34 HA antiserum for influenza virus classical reassortment. A/PR/8/34 virus was digested by bromelain after inactivation and purification. 5%-20% sucrose continuous density gradient centrifugation method was used to purify HA protein. SIRD method was used to select the target protein. SDS-PAGE method was used to identified HA protein. High Immunogenic A/PR/8/34 HA protein was successfully prepared and HI titer reached 10240. High purity HA antiserum was identified by SIRD method. The key reagent in the classical reassortment of influenza virus was prepared, and the complete set of technical methods were explored, which laid the foundation for the independent research and development of seasonal influenza vaccine strains of China.
Animals ; Antibodies, Viral ; immunology ; Electrophoresis, Polyacrylamide Gel ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinin Glycoproteins, Influenza Virus ; analysis ; immunology ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; immunology ; Influenza, Human ; immunology ; virology ; Rabbits ; Reassortant Viruses ; genetics ; immunology

Hemagglutinin (HA) contains a head domain with a high degree of variability and a relatively conserved stem region. HA is the major viral antigen on the surface of the influenza virus. To define the biologic activities of chimeric HA bearing different head domains and stem regions or their potential use, a HA chimeric gene containing the head domain of the H7 subtype virus and stem region of the H3 subtype virus was modified and expressed using a baculovirus expression vector. Then, the secreted protein was purified and its biologic activities characterized. Approximately 1.4 mg/mL cH7/3 HA could be obtained, and its molecular weight was ≈ 70 kD. The trimer form of cH7/3 protein had hemagglutination activity and could be recognized by specific antibodies. The method described here can be used for further studies on the screening of HA stem-reactive antibodies or the development of vaccines with conserved epitopes.
Antibodies, Viral ; immunology ; Baculoviridae ; genetics ; metabolism ; Gene Expression ; Genetic Vectors ; genetics ; metabolism ; Hemagglutination ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; immunology ; Humans ; Influenza Vaccines ; genetics ; immunology ; Influenza, Human ; prevention & control ; virology

Data based on the antiviral-resistant phenotyping characteristics of 884 influenza B viruses circulating in mainland China from October 2013 to March 2014 were analyzed to assess the susceptibility of influenza B viruses to neuraminidase inhibitors. All 884 viruses were sensitive to oseltamivir; two viruses (0.23%) had reduced sensitivity to zanamivir and all other viruses were sensitive to zanamivir. Among the 38 viruses with a B/Victoria lineage, B/Shandong-Kuiwen/1195/2014 exhibited a half-maximal inhibitory concentration (IC50) for zanamivir that was elevated by 5. 12-fold (1.78 nM) compared with neuraminidase inhibitors sensitive to the reference virus (0.34 nM), suggesting that it exhibited reduced inhibition by zanamivir. D35G, N59D and S402T (39, 64 and 399 with N2 number) amino-acid substitutions in the NA gene were detected with no previously reported antiviral-resistant substitutions. Among viruses with the 846 B/Yamagata lineage, B/Hunan-Lingling/350/2013 exhibited a 7.99-fold elevated IC50 for zanamivir (2.72 nM) compared with neuraminidase inhibitors sensitive to the reference virus (0.34 nM), suggesting that it exhibited reduced inhibition by zanamivir. D197N (N2 number), a previously reported antiviral resistant-related amino-acid substitution in the NA gene, was detected in B/Hunan-Lingling/350/2013. These data suggest that recently circulating influenza B viruses in mainland China have retained susceptibility to neuraminidase inhibitors.
Amino Acid Substitution ; Antiviral Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Viral ; Enzyme Inhibitors ; pharmacology ; Humans ; Influenza B virus ; drug effects ; enzymology ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Microbial Sensitivity Tests ; Neuraminidase ; antagonists & inhibitors ; genetics ; metabolism ; Viral Proteins ; antagonists & inhibitors ; genetics ; metabolism

In this study,thermosensitive and repairable molecularly imprinted solid-phase microextraction fibers were synthesized using spiramycin as template molecule,methacrylic acid and N-isopropylacrylamide as functional monomers,ethylene glycol dimethacrylate as crosslinking agent,and silanized quartz capillary as carrier. The prepared molecularly imprinted solid-phase microextraction fibers were characterized by scanning electron microscope and nitrogen adsorption/desorption,and various parameters affecting the extraction efficiency were optimized. Due to high selectivity and sensitivity of the fibers for macrolide antibiotics,the quantitative analysis of four macrolide antibiotics in food matrix,spiramycin,tilmicosin,tylosin,and josamycin,was peroformed in combination with high performance liquid chromatography. In the range of 0.5 to 50 μg/mL,the chromatographic peak area showed a good linear relationship with the concentration. The spike recoveries of the samples at three different addition levels were between 81.8% and 119.1%;the inter-day precisions were less than 13.8% (n=6),and the intra-day precisions were less than 15.5% (n=3).

The metastasis-associated lung adenocarcinoma transcription 1 (MALAT1) is a highly conserved long non-coding RNA (lncRNA) gene. However, little is known about the pathological role of lncRNA MALAT1 in glioma. In the present study, we explored the expression level of lncRNA MALAT1 in primary glioma tissues as well as in U87 and U251 glioma cell lines. Using qRT-PCR, we found that the expression of lncRNA MALAT1 was significantly increased in glioma tissues compared with that of paracancerous tissues. Meanwhile, the expression of MALAT1 was highly expressed in U98 and U251 cells. In order to explore the function of MALAT1, the expression of MALAT1 was greatly reduced in U87 and U251 cells transfected with siRNA specifically targeting MALAT1. Consequently, cell viability of U87 and U251 cells were drastically decreased after the knockdown of MALAT1. Concomitantly, the apoptosis rate of the two cell lines was dramatically increased. Furthermore, the expression levels of some tumor markers were reduced after the knockdown of MALAT1, such as CCND1 and MYC. In summary, the current study indicated a promoting role of MALAT1 in the development of glioma cell.
*Apoptosis ; Biomarkers, Tumor/genetics/metabolism ; Blotting, Western ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cyclin D1/genetics/metabolism ; Down-Regulation ; Flow Cytometry ; Glioma/metabolism/pathology ; Humans ; Proto-Oncogene Proteins c-myc/genetics/metabolism ; *RNA Interference ; RNA, Long Noncoding/antagonists & inhibitors/genetics/*metabolism ; RNA, Small Interfering/metabolism ; Real-Time Polymerase Chain Reaction

To analyze the antigenic and genetic characteristics of the influenza A (H3N2) virus in mainland China during the surveillance year of 2013-2014, the antigenic characteristics of H3N2 virus were analyzed using reference ferret anti-sera. The nucleotide sequences of the viruses were determined by Sanger dideoxy sequencing, phylogenetic trees were constructed with the neighbor-joining method, and the genetic characteristics of the viruses were determined in comparison to current vaccine strains. The results showed that most of the H3N2 viruses were antigenically closely related to the A/Victoria/361/2011 vaccine strain cell-propagated prototype virus (99.6%). Using the A/Texas/50/2012 egg isolate as the reference antigen, 15.1% of the viruses were found to be closely antigenically related to it, while 11.9% of strains were closely antigenically related to the egg-propagated epidemic strain, A/Shanghai-Changning/1507/2012. Phylogenetic analysis of HA genes indicated that the A(H3N2) viruses in this surveillance year were in the same clade, but no drug resistant mutation was identified in the NA genes. During the 2013-2014 influenza surveillance year, no significant genetic change was detected in either the HA or NA genes of the A(H3N2) viruses, while significant mutations were found in egg isolates resulting from their adaptation during propagation in eggs. The antigenic and genetic changes should be investigated in a timely manner to enable the selection of an appropriate vaccine strain in China.
Animals ; Antigenic Variation ; Base Sequence ; Chick Embryo ; China ; Genetic Variation ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; immunology ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; immunology ; isolation & purification ; Influenza, Human ; virology ; Molecular Sequence Data ; Mutation ; Phylogeny

To assess relationships between xanthine oxidase (XOD) and nephropathogenic infectious bronchitis virus (NIBV) infection, 240 growing layers (35 days old) were randomly divided into two groups (infected and control) of 120 chickens each. Each chicken in the control and infected group was intranasally inoculated with 0.2 mL sterile physiological saline and virus, respectively, after which serum antioxidant parameters and renal XOD mRNA expression in growing layers were evaluated at 8, 15 and 22 days post-inoculation (dpi). The results showed that serum glutathione peroxidase and superoxide dismutase activities in the infected group were significantly lower than in the control group at 8 and 15 dpi (p < 0.01), while serum malondialdehyde concentrations were significantly higher (p < 0.01). The serum uric acid was significantly higher than that of the control group at 15 dpi (p < 0.01). In addition, the kidney mRNA transcript level and serum activity of XOD in the infected group was significantly higher than that of the control group at 8, 15 and 22 dpi (p < 0.05). The results indicated that NIBV infection could cause the increases of renal XOD gene transcription and serum XOD activity, leading to hyperuricemia and reduction of antioxidants in the body.
Antioxidants ; Chickens ; Glutathione Peroxidase ; Hyperuricemia ; Infectious bronchitis virus* ; Kidney ; Malondialdehyde ; RNA, Messenger* ; Superoxide Dismutase ; Uric Acid ; Xanthine Oxidase* ; Xanthine*

OBJECTIVETo investigate the pathogenesis and immunogenicity of H9N2 influenza virus A/Guangzhou/333/99 (a reassortant of G1 and G9 viruses isolated from a female patient in 1999) in a mouse model of infection.

METHODSMice were infected with increasing virus titers. Viral load in the lungs and trachea was determined by EID50 assay. Pulmonary histopathology was assessed by hematoxylin-eosin staining. Anti-HI antibody titers and T-cell responses to viral HA were determined by ELISPOT and confirmed by flow cytometry.

RESULTSMice presented a mild syndrome after intranasal infection with A/Guangzhou/333/99 (H9N2) influenza virus. Virus was detected in the trachea and lungs of mice harvested on days 3, 6, and 9 post-infection. A T-cell response to viral HA was detected on day 6 and H9 HA-specific CD(4+) T-cells predominated. Seroconversion was detected after 14 days and antibody persisted for at least 28 weeks.

CONCLUSIONOur results suggest that H9N2 (A/Guangzhou/333/99) can replicate in the murine respiratory tract without prior adaptation, and both humoral and cell-mediated immunity play an important role in the immune response.

Animals ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; Cell Line ; Dogs ; Enzyme-Linked Immunospot Assay ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinins, Viral ; immunology ; Humans ; Infant ; Influenza A Virus, H9N2 Subtype ; immunology ; isolation & purification ; pathogenicity ; Interferon-gamma ; immunology ; Lung ; virology ; Lymphocytes ; immunology ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; immunology ; virology ; Spleen ; immunology ; Trachea ; virology ; Viral Load ; Virulence

We developed vectors expressing two antigen of H5N1 influenza virus. Based on the human H5N1 avian influenza virus strain A/Anhui/1/2005 isolated in China, we amplified the matrix protein 2 (M2) and Hemagglutinin (HA) genes by PCR and subcloned them into pStar vector to construct two genes co-expressing recombinant DNA vaccine pStar-M2/HA. After transfection of 293 cells with the plasmid, we confirmed with indirect immunofluorescence assay (IFA) that M2 and HA genes cloned on plasmid pStar co-expressed successfully. Using Ad-Easy adenovirus vector system, by homologous recombination in bacteria and packaging in 293 cells, we constructed two recombinant adenoviruses, namely Ad-M2 and Ad-HA. After infection of 293 cells with the recombinant adenoviruses, we confirmed with IFA that M2 and HA genes cloned into adenoviruses expressed successfully. We then combined the recombinant DNA vaccine and adenoviral vector vaccines in immunization of BALB/c mice with a prime-boost regime. On day 0 and day 28, we immunized the mice with DNA vaccine and on day 14 and day 42, with recombinant adenovirus vaccines. We took blood samples before each injection and 14 days after the final injection. On day 56, we collected splenocytes from the mice. ELISA and hemagglutination inhibition (HI) assay showed that the vaccines successfully induced specific IgG antibodies against HA protein in serum of the immunized mice. ELISPOT confirmed that the vaccines successfully induced the special cellular immune response to M2 and HA protein of H5N1 influenza virus. The study on combined immunization with M2 and HA genes provided basis for development of novel influenza vaccine.
Adenoviridae ; genetics ; metabolism ; Animals ; Female ; Genetic Vectors ; genetics ; Hemagglutinin Glycoproteins, Influenza Virus ; biosynthesis ; genetics ; Influenza A Virus, H5N1 Subtype ; genetics ; immunology ; Influenza Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Vaccination ; Vaccines, DNA ; immunology ; Viral Matrix Proteins ; biosynthesis ; genetics