A plasmids of continuous expressing shRNAs targeting the NDV NA-1 Phosphoprotein (P) gene was designed.Virus titration,Real Time RT-PCR,CPE indicated that P-specific siRNA could inhibit virus replication at 36 h post-virus infection.In future studies,a combination of siRNAs targeting the NP and L gene may be used as a tool to study NDV replication and antiviral therapy.

One strain of PRRSV was isolated from tissue of piglets died of obvious respiratory syndrome and high fever.It was identified as a strain of American type PRRSV by serological test and gene sequencing.According to American type PRRSV VR-2332,we designed 3 pairs of primers to aim directly at N gene,GP5 gene and variation sequence of NSP2.The results of sequence analysis indicated a discontinuous deletion of 30 amino acids in nonstructural protein 2 (NSP2).N and GP5 gene is conservative relatively.

Objective:To evaluate the protective immunity by vaccination of BALB/c mice with rLV-HA-GCN4,a recombinant lentivirus expressing the trimeric HA of swine H1N1 influenza virus. Methods:The female mice were randomly divided into rLV-HA-GCN4,rLV-HA,LV and PBS groups. Mice were primed with plasmid and boosted with lentivirus by the administration of intramuscular thigh injections at an interval of two weeks. At day 28 post-prime immunization,mice were inoculated intranasally with 100TCID50 of swine H1N1 influenza virus in a 50 μl volume. The immune levels were assessed by the T lymphocyte transformation test, flow cytometry,indirect ELISA and the indexes of spleen and lung. Results:The spleen lymphocyte transformation rate was 0. 3±0. 11 in the rLV-HA-GCN4 group at day 14 post-boost immunization, showing a statistical significance ( P<0. 01 ) compared to the PBS group. Meanwhile,rLV-HA-GCN4 could cause T lymphocyte response mainly based on the Th1-type CD4+ T cells. The IgG antibody titer reached to 1:8 000 at day 14 post-boost immunization and approximately 1:7 000 at day 14 post challenge. After challenge,the spleen and lung indexes of rLV-HA-GCN4 group were significantly lower than those of PBS group (P<0. 05). The body weight of rLV-HA-GCN4 group demonstrated a slight decrease before 3 days post challenge and then a gradual increase compared to the LV and PBS groups (P<0. 05). Conclusion:rLV-HA-GCN4 can effectively induce cellular and humoral immune response in BALB/c mice against swine H1N1 influenza virus.

Infectious bronchitis in chickens is a serious threat to the global poultry industry.Despite the availability of commercial vaccines,the epidemic has not been effectively controlled.Therefore,the development of novel vaccines may provide new ways to prevent and control this disease.In this study,BLP-S1,a bacterium-like particle displaying the S1 subunit of infectious bronchitis virus on its surface,was constructed using the GEM-PA system.The immunoprotection results showed that BLP-S1 effectively induced the production of specific IgG and sIgA in commercial chickens and provided effective protection against a heterologous strain with a protection rate of up to 90％.This study demonstrated that BLP-S1 has good immunogenicity and immunoprotection,with the poten-tial to develop a novel vaccine against infectious bronchitis.

Given that the current Newcastle disease virus (NDV) infection in wild birds poses the threat to poultry, surveillance of Newcastle disease in captive wild birds was carried out in Jilin, China in 2018. Here, an NDV strain obtained from toco toucan was firstly characterized.The results showed that the F gene of the NDV isolate Toucan/China/3/2018 is classified as genotype II in class II. Sequence analysis of the F0 cleavage site was 113 RQGR/L 117 , which supports the result of the intracerebral pathogenicity index assay indicating classification of the isolate as low-pathogenicity. Experimental infection demonstrated that Toucan/ China/3/2018 can effectively replicate and transmit among chickens. To our knowledge, this is the first report on genetically and pathogenically characterizing NDV strain isolated from toucan, which enriches the epidemiological information of NDV in wild birds.

Characteristic clinical manifestations of Newcastle disease include leukopenia and immunosuppression. Peripheral blood mononuclear cells (PBMCs) are the main targets of Newcastle disease virus (NDV) infection. To survey changes in proteomic expression in chicken PBMCs following NDV infection, PBMC proteins from 30 chickens were separated using two-dimensional electrophoresis (2-DE) and subjected to mass spectrometry analysis. Quantitative intensity analysis showed that the expression of 78 proteins increased more than two-fold. Thirty-five proteins exhibited consistent changes in expression and 13 were identified as unique proteins by matrix assisted laser desorption ionization-time of flight mass spectrometer/mass spectrometer including three that were down-regulated and 10 that were up-regulated. These proteins were sorted into five groups based on function: macromolecular biosynthesis, cytoskeleton organization, metabolism, stress responses, and signal transduction. Furthermore, Western blot analysis confirmed the down-regulation of integrin-linked kinase expression and up-regulation of lamin A production. These data provide insight into the in vivo response of target cells to NDV infection at the molecular level. Additionally, results from this study have helped elucidate the molecular pathogenesis of NDV and may facilitate the development of new antiviral therapies as well as innovative diagnostic methods.
Animals ; Avian Proteins/*genetics/metabolism ; *Chickens ; *Gene Expression Regulation ; Leukocytes, Mononuclear/enzymology/virology ; Newcastle Disease/*genetics/virology ; Newcastle disease virus/*physiology ; Poultry Diseases/*genetics/virology ; *Proteome ; Specific Pathogen-Free Organisms ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/veterinary ; Tandem Mass Spectrometry/veterinary