Isolation and pathotyping of H9N2 avian influenza viruses in Indian poultry.
ABSTRACT A total of 1246 faecal and tissue samples collected/received from 119 farms located in various states of India were processed for isolation of avian influenza viruses (AIV) during 2003-2004 as part of a program to monitor AIV infection in Indian poultry population. Avian influenza virus was isolated for the first time in India from poultry farms with history of drop in egg production, respiratory illness and increased mortality in Haryana state. A total of 29 H9N2 AIV isolates were obtained from the states of Punjab, Haryana, Uttar Pradesh, Gujarat, and Orissa and Union Territory Delhi. Subtyping was done by HI, RT-PCR and neuraminidase inhibition assay. Pathotyping of six representative isolates by intravenous pathogenicity index (0.0/3.0) in 6-8 weeks old chicken, trypsin dependency in cell culture and HA cleavage site analysis (335RSSR*GLF341) confirmed that these isolates are low pathogenic. Nucleotide sequence analysis of the HA gene showed that the Indian isolates are very closely related (95.0-99.6%) and shared a homology of 92-96% with H9N2 isolates from Germany and Asian regions other than that of mainland China. Deduced amino acid sequences showed the presence of L226 (234 in H9 numbering) which indicates a preference to binding of alpha (2-6) sialic acid receptors. Two of the six isolates had 7 glycosylation sites in the HA1 cleaved protein and the remaining four had 5 sites. Phylogenetic analysis showed that they share a common ancestor Qa/HK/G1/97 isolate which had contributed internal genes of H5N1 virus circulating in Vietnam. Further characterization of Indian H9N2 isolates is required to understand their nature and evolution.
- SourceAvailable from: PubMed Central[Show abstract] [Hide abstract]
ABSTRACT: An H9N2 virus lethal to chickens was isolated from an acutely ill chicken flock in 2012. Phylogenetic analyses indicated that this virus was phylogenetically related to the Y280 lineage. Sequence analysis showed 1 amino acid deletion in HA1 and 3 amino acid deletions in the NA stalk region. Copyright © 2014 Zhang et al.Genome announcements. 01/2014; 2(6).
- [Show abstract] [Hide abstract]
ABSTRACT: Single chain fragment variable (ScFv) antibodies specific to the nucleoprotein (NP) of avian influenza virus (AIV) were developed using a phage display system. The variable heavy (VH) and the variable light (VL) chain gene fragments were derived from spleen cells of Balb/c mouse immunized with a recombinant NP (rNP) antigen (∼63kDa) of H5N1 influenza virus. The VH and the VL DNA fragments were assembled through a flexible linker DNA to generate ScFv DNA that was cloned subsequently in a phagemid to express ScFv protein in E. coli cells. The specific reactivity of the ScFv with the rNP antigen and viral antigen (H5N1) was confirmed by Western blot and ELISA. A competitive inhibition ELISA (CI-ELISA) was developed using the rNP and the anti-NP ScFv for detection of type-specific antibodies to AIV in chicken sera. The ScFv based CI-ELISA was compared with hemagglutination inhibition (HI) test and Agar Gel Immuno-Diffusion (AGID) test over 850 sera. Sensitivity of the CI-ELISA was 100% with HI and AGID and specificity was 98.7% with HI and 100% with AGID.Journal of virological methods. 08/2014;
Article: 4. Sood R, Bhatia S, Bhatnagar H, Gupta V, Kumar M, Dimri U, Swarup D.(2013) Phytochemical analysis and in vitro screening of selected Indian medicinal plants for antiviral activity against highly pathogenic avian influenza virus. Spatula DD- Peer Reviewed Journal on Alternative and Complementary Medicine and Drug Discovery. 2013; 3(3): 81-88Spatula DD- Peer Reviewed Journal on Alternative and Complementary Medicine and Drug Discovery. 01/2013; 3(3):81-88.