ABSTRACT
Objective:To analyze the genetic evolution and molecular characteristics of H5N8 avian influenza viruses (AIVs) isolated from the poultry in a live poultry market (LPM) in Urumqi, Xinjiang.Methods:Oropharyngeal and cloacal swabs of poultry were collected from a LPM in Urumqi in 2016. AIVs were isolated by inoculating swab samples into chicken embryos. Hemagglutination test and RT-PCR were used to identify the AIVs. The genes of isolated AIVs were amplified with the universal primers of AIV and whole-genome sequencing was also performed. Pairwise sequence alignment and analysis of phylogenetic and molecular characteristics were performed using BLAST, Clustal W, MEGA-X and DNAStar software.Results:Five H5N8 AIVs were isolated from poultry. These strains shared a nucleotide identity of 99.70%-100.00%, which indicated that they were from the same source, and were named XJ-H5N8/2016. Phylogenetic analysis based on hemagglutinin( HA), NS and PB2 genes showed that these isolates were clustered together with H5N8 AIVs isolated from the migratory swans in Hubei, Shanxi and Sanmenxia, and the ducks in India during 2016 to 2017. Moreover, they were also clustered together with H5N6 AIVs isolated from minks in China and the first case of human infection in Fujian. The phylogenetic tree of neuraminidase( NA) gene indicated the five isolates clustered together with H5N8 AIVs isolated from ducks in India in 2016, and the phylogenetic trees of PB1, MP, PA and NP genes showed that they were clustered together with H5N8 AIVs isolated from wild birds and poultry in Egypt, Cameroon, Uganda, Congo and other African countries in 2017. The HA cleavage sites of XJ-H5N8/2016 contained five consecutive basic amino acids, indicating high pathogenicity. Multiple mutations in the genes of XJ-H5N8/2016 could enhance its virulence and pathogenicity to mammals. Conclusions:The five strains of H5N8 AIVs isolated from the LPM were highly pathogenic and closely related to the H5N8 AIVs isolated from migratory birds and poultry in Hubei, Shanxi, Sanmenxia area, Africa and India during 2016 to 2017. Meanwhile, some of the viral genes were also closely related to the H5N6 AIVs isolated from the minks and human in China. Multiple mutations could increase the virulence and pathogenicity of AIVs to mammals, which could pose a potential threat to public health.
ABSTRACT
Background@#The H5 avian influenza viruses (AIVs) of clade 2.3.4.4 circulate in wild and domestic birds worldwide. In 2017, nine strains of H5N6 AIVs were isolated from aquatic poultry in Xinjiang, Northwest China. @*Objectives@#This study aimed to analyze the origin, reassortment, and mutations of the AIV isolates. @*Methods@#AIVs were isolated from oropharyngeal and cloacal swabs of poultry. Identification was accomplished by inoculating isolates into embryonated chicken eggs and performing hemagglutination tests and reverse transcription polymerase chain reaction (RT-PCR). The viral genomes were amplified with RT-PCR and then sequenced. The sequence alignment, phylogenetic, and molecular characteristic analyses were performed by using bioinformatic software. @*Results@#Nine isolates originated from the same ancestor. The viral HA gene belonged to clade 2.3.4.4B, while the NA gene had a close phylogenetic relationship with the 2.3.4.4C H5N6 highly pathogenic avian influenza viruses (HPAIVs) isolated from shoveler ducks in Ningxia in 2015. The NP gene was grouped into an independent subcluster within the 2.3.4.4B H5N8 AIVs, and the remaining six genes all had close phylogenetic relationships with the 2.3.4.4B H5N8 HPAIVs isolated from the wild birds in China, Egypt, Uganda, Cameroon, and India in 2016–2017, Multiple basic amino acid residues associated with HPAIVs were located adjacent to the cleavage site of the HA protein. The nine isolates comprised reassortant 2.3.4.4B HPAIVs originating from 2.3.4.4B H5N8 and 2.3.4.4C H5N6 viruses in wild birds. @*Conclusions@#These results suggest that the Northern Tianshan Mountain wetlands in Xinjiang may have a key role in AIVs disseminating from Central China to the Eurasian continent and East African.
ABSTRACT
Background@#The H5 avian influenza viruses (AIVs) of clade 2.3.4.4 circulate in wild and domestic birds worldwide. In 2017, nine strains of H5N6 AIVs were isolated from aquatic poultry in Xinjiang, Northwest China. @*Objectives@#This study aimed to analyze the origin, reassortment, and mutations of the AIV isolates. @*Methods@#AIVs were isolated from oropharyngeal and cloacal swabs of poultry. Identification was accomplished by inoculating isolates into embryonated chicken eggs and performing hemagglutination tests and reverse transcription polymerase chain reaction (RT-PCR). The viral genomes were amplified with RT-PCR and then sequenced. The sequence alignment, phylogenetic, and molecular characteristic analyses were performed by using bioinformatic software. @*Results@#Nine isolates originated from the same ancestor. The viral HA gene belonged to clade 2.3.4.4B, while the NA gene had a close phylogenetic relationship with the 2.3.4.4C H5N6 highly pathogenic avian influenza viruses (HPAIVs) isolated from shoveler ducks in Ningxia in 2015. The NP gene was grouped into an independent subcluster within the 2.3.4.4B H5N8 AIVs, and the remaining six genes all had close phylogenetic relationships with the 2.3.4.4B H5N8 HPAIVs isolated from the wild birds in China, Egypt, Uganda, Cameroon, and India in 2016–2017, Multiple basic amino acid residues associated with HPAIVs were located adjacent to the cleavage site of the HA protein. The nine isolates comprised reassortant 2.3.4.4B HPAIVs originating from 2.3.4.4B H5N8 and 2.3.4.4C H5N6 viruses in wild birds. @*Conclusions@#These results suggest that the Northern Tianshan Mountain wetlands in Xinjiang may have a key role in AIVs disseminating from Central China to the Eurasian continent and East African.
ABSTRACT
Objective:To analyze phylogenetic structure and molecular characteristics of H5N6 avian influenza virus (AIVs) isolated from live poultry market (LPM).Methods:Oropharyngeal and cloacal swabs from poultry, and environmental samples were collected from LPM in Urumqi in December 2018, AIVs were isolated and identified by inoculation of chicken embryo, hemagglutination test and RT-PCR, the viral whole genome was amplified with the universal primers of influenza A virus, and then sequenced, pairwise sequence alignments, phylogenetic and molecular characteristics analysis were performed by BLAST, Clustal W, MEGA-X and DNAStar software.Results:Six strains of H5N6 AIVs were isolated from poultry samples, the identity between the viral genes was high (99.4%-100.0%), so the isolates were the same source. BLAST analysis revealed that the viral NP sequence had the highest identity (99.7%) with H5N6 AIVs isolated from poultry in Suzhou, while the sequence of the remaining 7 viral genes had the highest identity (99.0%-100.0%) with H5N6 AIVs isolated from environment in Guangdong during 2017 to 2018. Phylogenetic analysis showed that the viral HA belonged to Clade 2.3.4.4C, and the viral HA, NA, PB1, PA, NP, and MP were all clustered together with H5N6 AIVs isolated from mink in Eastern China in 2018, while the PB2 and NS were clustered together with H5N6 AIVs isolated from environment in Guangdong from 2017 to 2018. The HA cleavage site contained multiple basic amino acid residues, which was highly pathogenic AIVs (HPAIVs). S137A and T160A mutations of HA could increase binding to human-type receptor SAα2, 6-Gal. Additionally, the viral multiple mutations, including 59-69 deletion in NA, the L89V, G309D, R477G, I495V, I504V, D391E, and A661E in PB2, as well as the P42S, D92E, and 80-84 deletion in NS1, could enhance the viral virulence and pathogenicity to mammals. Conclusions:The 6 strains of H5N6 HPAIVs isolated from LPM have relatively close genetic relationship with H5N6 AIVs isolated from mink in Eastern China and environment in Guangdong during 2017 to 2018, the viral multiple mutations could increase its pathogenicity to mammals, which could pose a potential risk to public health.
ABSTRACT
Objective:To analyze the complete genome sequence and phylogenetic structure of a wild bird-derived H1N1 avian influenza virus (AIV) in the northern Tianshan Mountain.Methods:In November 2018, 320 samples of fresh wild bird feces were collected from several reservoirs in the middle part of northern Tianshan Mountain. Chicken embryo inoculation test, hemagglutination inhibition test and RT-PCR with PB1 universal primer were used to isolate and identify AIVs. Eight fragments of the viral genome were amplified with the universal primers of influenza A virus and the whole viral genome was sequenced. Pairwise sequence alignments and analysis of phylogenetic and molecular characteristics were performed by BLAST, Clustal W, MEGA7.0 and MegAlign software. Results:Influenza viruses were isolated and identified from six samples of wild bird feces with a positive rate of 1.88%. One of them was H1N1 AIV, named A/wild bird/Xinjiang/010/2018 (H1N1) (XJ-H1N1). The eight gene segments of XJ-H1N1 were all derived from AIVs isolated from wild ducks of Anseriformes. The surface genes of HA and NA were Eurasian lineages and derived from H1N1 isolated from Mongolian Anas platyrhynchos and H3N1 isolated from Bangladesh wild duck, respectively. The six internal genes were derived from H6N8 isolated from Anas strepera in Siberia, H7N3 isolated from Anas clypeata and teal in Egypt, and H7N5 isolated from wild birds such as Anas platyrhynchos in the Netherlands. The HA cleavage site of XJ-H1N1 contained only one basic amino acid, suggesting that it was a low pathogenic AIV. Amino acids at positions 190 and 225 of HA receptor binding sites were E and G (H3 count), which could bind both α2, 3 galactoside sialic acid (SAα2, 3Gal) and SAα2, 6Gal receptors. T200A and E227A mutations in HA amino acid sequences and P42S mutation in NS1 amino acid sequences could all enhance the replication ability and pathogenicity of the virus in mammalian cells. Conclusions:A low pathogenic H1N1 AIV, XJ-H1N1, was isolated from wild birds in the northern Tianshan Mountain, resulting from multiple reassortments of AIVs carried by migrating wild ducks. The replication capacity and pathogenicity of XJ-H1N1 in mammalian cells might be enhanced. Moreover, the virus could bind both SA 2-3gal and SA 2-6gal receptors.
ABSTRACT
Background and purpose:The incidence of cervical cancer is rather high in Xinjiang, which is closely associated with the infection of human papilloma virus type 16 (HPV-16). The purpose of this study was to analyze the variants and function of HPV-16 upstream regulatory region (URR) in the tissues of cervical cancer biopsies from Xinjiang.Methods:The DNAs were extracted from the tissues of cervical epithelial atypical hyperplasia (CIN) and cervical cancer biopsies. HPV-16URR segments were ampliifed by PCR. Based on the sequence analysis of the URR, the representativeURR variants were selected and cloned into pGL3-Basic. The recombinant plasmids were transfected into Vero cell lines respetively. Luciferase activity of transfected cells was detected 48 h after transfection. Results:Fifty-ifve HPV-16URR DNA fragments were obtained through PCR, and 44 mutations were found from the URR fragments. 4 of these mutations, including nt7192(G→T) , nt7433(- →T), nt7435 (C→G) and nt7863 (A→-) occurred in all sequences. The mutation at nt7520 (G→A) occurred in 54URR sequences, and the 39 other mutations were present in different samples. Based on the location and frequency of the mutations in theURR fragments, 9URR variants were selected and cloned into pGL3-Basic. Then the luciferase activity of the cells transfected with pGL3-URR plasmids was detected respectively. Promoter activity ofURR mutants from cervical cancer are significantly higher than that ofURR mutants from CIN (P<0.01). Promoter activity ofURR fragments from some cervical cancer was signiifcantly higher than that of theURR fragments from SiHa and Caski cells.Conclusion:Multiple mutations occurred in HPV-16URR of cervical cancer patients from Xinjiang. The promoter activity and carcinogenicity of some URR mutants have been enhanced.
ABSTRACT
To construct an HSV-1 vector vaccine carrying HIV-1 antigens, HIV-1 gp160, gag, protease and the expression elements were chained together, and then inserted into the internal inverted repeat sequence region of HSV-1 by bacterial artificial chromosome technology. Firstly, HIV-1 gp160 (including type B and C), gag and protease genes were cloned into pcDNA3 in series to generate the pcDNA/gBgp and pcDNA/gCgp, then the recombinant plasmids were transfected into 293FT cells, and HIV-1 antigen was detected from transfected cells by Western blotting. Then the expression cassettes from pcDNA/gBgp and pcDNA/gCgp, comprising HIV-1 antigen genes and expression elements, were cloned into pKO5/BN to generate the shuttle plasmids pKO5/BN/gBgp and pKO5/BN/gCgp. The shuttle plasmids were electroporated into E. coli cells that harbor an HSV-BAC, the recombinant bacteria were screened, and the recombinant DNA was extracted and transfected into Vero cells. The recombinant virus was purified through picking plaques, the virus' DNAs were identified by Southern blotting; HIV-1 antigen was detected from the recombinant HSV-1 infected cells by Western blotting, and the virus' replication competent was analyzed. As the results, gp160 and gag proteins were detected from 293FT cells transfected with pcDNA/gBgp and pcDNA/gCgp by Western blotting. The recombinant bacteria were generated from the E. coli electroporated with pKO5/BN/gBgp or pKO5/BN/gCgp. The recombinant HSV was purified from the Vero cells transfected with the recombinant DNA, the unique DNA fragment was detected from the genome of recombination HSV by Southern blotting; gp120 and gp41 were detected from the infected cells by Western blotting, and the recombinant HSV retained replication competent in mammalian cells. The results indicate that the recombinant HSV carrying HIV-1 gp160, gag and protease genes was generated, the virus retains replication competent in mammalian cells, and could be used as a replicated viral vector vaccine.
Subject(s)
Animals , Chlorocebus aethiops , Chromosomes, Artificial, Bacterial , DNA, Recombinant , Genetics , DNA, Viral , Genetics , Escherichia coli , HIV Antigens , Genetics , Allergy and Immunology , HIV Envelope Protein gp160 , Genetics , Allergy and Immunology , HIV Protease , Genetics , Allergy and Immunology , Herpes Simplex Virus Vaccines , Allergy and Immunology , Herpesvirus 1, Human , Physiology , Plasmids , Transfection , Vero Cells , Virus Replication , gag Gene Products, Human Immunodeficiency Virus , Genetics , Allergy and ImmunologyABSTRACT
Mammalian zona pellucida 3(ZP3) plays an important role in the induction of capacitating sperm acrosome reaction. In this study, we obtained the soluble mZP3 fusion protein and identified its immunoreactivity. mZP3 cDNA was cloned into plasmid pMAL-p2x, and the recombinant plasmid was transformed into Escherichia coli BL21. To get the soluble mZP3 fusion protein, we tried to optimize the expression conditions, including additives, IPTG concentrations, temperatures and induction duration. Then, Western blotting and ELISA were used to identify the immunoreactivity of the purified protein. Based on the optimization experiments, we concluded that the best soluble expression conditions for the mZP3 fusion protein involved incubation to an A600 of 0.6, addition of glucose to a final concentration of 0.02 mol/L, addition of IPTG to a final concentration of 0.6 mmol/L and then further incubation for 4 h at 25 degrees C. Western blotting and ELISA showed that the mZP3 fusion protein retained immunoreactivity. The fusion protein can be used as solubility antigens for developing the immunocontraception vaccines of mZP3 and detecting the immune effects of the vaccine.