A Tenofovir-Loaded Glycyrrhetinic Acid-Modified Cationic Liposome for Targeted Therapy of Hepatitis B Virus

Tenofovir (TFV), an acyclic nucleoside analog, exhibits potent anti-HBV activity. However, poor bioavailability, nephrotoxicity and bone toxicity limit its further clinical application. In this work, a novel tenofovir-loaded glycyrrhetinic acidmodified cationic liposome (TGCL) was prepared for targeted therapy of HBV. The TGCL had an average particle size of 107.39 ± 1.21 nm and an entrapment efficiency of 89.83 ± 2.70% with a positive zeta potential of 37.63 ± 1.22 mV. The results of in vitro indicated that the inhibitory effects on HBsAg, HBeAg and HBV cccDNA of TGCL in HepG2.2.15 cells were significantly better than that of free TFV and non-targeted cationic liposome. In the DHBV-infected duck model, TGCL showed remarkably suppression on DHBV DNA than that of free TFV. Overall, TGCL is a promising formulation of TFV for targeted therapy of HBV.

Molecular Characterization and Pathogenicity of an Indian Isolate of Duck Enteritis Virus Recovered From a Natural Outbreak

Background: Duck plague is a highly contagious viral disease reported in our country very often with significant economic loss. There are some bottlenecks with the currently used ‘Holland strain’ vaccine that involves cumbersome process of vaccine production in embryonated chicken eggs. With the future goal of development of an indigenous cell culture vaccine for duck plague, the present study is aimed at isolation of an Indian strain of DEV from a natural outbreak and its characterization for the seed virus purpose. Methods: Liver samples were collected from the suspected ducks died during a natural outbreak in Kerala and subjected to polymerase chain reaction (PCR) to confirm presence of viral DNA. The duck enteritis virus (DEV) was isolated by inoculation of PCR positive samples in embryonated duck eggs/ducklings and its pathogenicity was studied. Further, the DEV recovered from the infected duck embryo and duckling liver was confirmed by PCR amplification of the viral DNA polymerase gene and its sequence analysis. Result: Out of 12 liver samples tested eight (8) were found to be positive for duck plague by PCR. The DEV infected duck embryos and ducklings died showing typical signs and characteristic gross and microscopic lesions. PCR amplification of viral DNA targeting the DNA polymerase gene yielded amplicon of expected size of 446bp. The amplicon sequence showed 99-100% homology with other DEV isolates, thus confirming the new isolate as DEV, named as DEV/India/IVRI-2016 and the gene sequence has NCBI acc. no. KX511893.

Transcriptome Analysis Reveals the Neuro-Immune Interactions in Duck Tembusu Virus-Infected Brain

The duck Tembusu virus (DTMUV) is a mosquito-borne flavivirus. It causes severe symptoms of egg-drop, as well as neurological symptoms and brain damage in ducks. However, the specific molecular mechanisms of DTMUV-induced neurovirulence and host responses in the brain remain obscure. To better understand the host–pathogen and neuro-immune interactions of DTMUV infection, we conducted high-throughput RNA-sequencing to reveal the transcriptome profiles of DTMUV-infected duck brain. Totals of 117, 212, and 150 differentially expressed genes (DEGs) were identified at 12, 24, and 48 h post infection (hpi). Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses uncovered genes and pathways related to the nervous system and immune responses in duck brain. Neuro-related genes, including WNT3A, GATA3, and CHRNA6, were found to be significantly downregulated. RIG-I-like receptors (DHX58, IFIH1) and Toll-like receptors (TLR2 and TLR3) were activated, inducing the expression of 22 interferon stimulated genes (ISGs) and antigen-processing and -presenting genes (TAP1 and TAP2) in the brain. Our research provides comprehensive information for the molecular mechanisms of neuro-immune and host–pathogen interactions of DTMUV.

The pathogenecity of H5N1 highly pathogenic Avian Influenza (HPAI) virus clade 2.3.2. in Indonesian indigenous chicken by contact tranmission with infected duck

An experimental transmission study was conducted using nine healthy Indonesian indigenous chickens placed together with two 30 days old ducks which were experimentally infected with H5N1 HPAI clade 2.3.2 virus in the Biosafety Laboratory Level 3 (BSL-3) facilities. The aim of the study was to find out the pathogenicity of H5N1 HPAI virus clade 2.3.2 in Indonesian indigenous chickens. The study showed that within twenty four hours rearing, the chickens were exhibited mild clinical signs and by 48 hours, all of the chickens died, whereas the ducks survived but with severe clinical signs. The H5N1 HPAI virus has been successfully isolated from chickens and ducks swabs, confirming that those animals were infected by the virus. Histologically, the infected chicken encountered with severe inflammation reaction namely non suppuratives encephalitis, tracheitis, myocarditis, interstitial pneumonia, hepatitis, proventriculitis, enteritis, pancreatitis, nephritis and bursitis. Necrotizing spleen and pancreas were also prominent. Viral antigen was detected by immunohistochemistry staining in various affected visceral organs. This suggests that Indonesian indigenous chickens were susceptible to H5N1 HPAI virus clade 2.3.2 and it can be transmitted easily to Indonesian indigenous chickens by contact transmission with infected ducks.