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Japanese encephalitis virus (JEV) is a flavivirus that cause severe neurological deficits. The guanylate-binding protein 1 (GBP1) gene is an interferon-stimulated gene and exerts antiviral functions on many RNA and DNA viruses via diverse mechanisms, however, the roles and the action modes of GBP1 in the antiviral effect on the production of JEV RNA and infectious virions remain to be clarified. In this study, we found that the RNA levels of swine GBP1 (sGBP1) in PK15 cells were up-regulated at the late stage of JEV infection. The overexpression of sGBP1 significantly inhibited the production of JEV while the knockdown of sGBP1 promoted the production of JEV. The GTPase activity and isoprenylation of sGBP1 both are critical for anti-JEV activity. The GTPase activity of sGBP1 is responsible for inhibiting the production of JEV genomic RNA. The isoprenylation of sGBP1 inhibited the expression and cleavage of JEV prM to decrease the yields of infectious virions, which may be associated with the interaction between sGBP1 and cellular proprotein convertase furin. Taken together, the study dissected the action modes of sGBP1with potent anti-JEV activity in more details., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bluetongue virus (BTV), a vector-borne pathogen, is the causative agent of bluetongue disease in ruminants. In view of the recent emergence of BTV in regions previously known to be free from the disease and/or specific serotypes or strains, optimization of the currently available vaccination strategies to control the spread of vector-borne bluetongue is crucial. The main objective of the current study was to develop a subunit vaccine candidate targeting BTV-16, a strain previously isolated in China from sheep with obvious clinical signs. To this end, five polyhistidine-tagged recombinant proteins (BTV-16 VP2, VP3, VP7, NS2 and a truncated version of VP5 (VP5-41amino acids) were expressed using the baculovirus or Escherichia coli expression system for characterization of protective activity. To determine ovine and murine immune responses to the five proteins, sheep and mice were immunized twice at 4- and 2-week intervals, respectively, with one of two different protein combinations in Montanide TM ISA201 VG adjuvant or placebo. Data from the competitive enzyme linked immunosorbent assay revealed significantly higher antibody titers in immunized than control animals. Expressed VP5 and NS2 induced a protein-specific humoral response. Interestingly, a serum neutralization test against the BTV-1 serotype showed promising cross-serotype immune response by the vaccine. Based on the collective data, we suggest that these recombinant purified proteins present promising candidates for the design of effective novel vaccines against BTV., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Bovine ephemeral fever (BEF) is caused by the arthropod-borne bovine ephemeral fever virus (BEFV), which is classified in the family Rhabdoviridae and the genus Ephemerovirus. A debilitating and sometimes fatal viral disease, BEF affects cattle and water buffalo. The epizootiology of BEF among cattle in China has not been fully determined. We examined the seroprevalence of the BEFV among cattle in China between January 2012 and June 2014. Among the 2822 serum samples collected from various cattle breeds in 26 provinces in China, the seropositive rate for the BEFV ranged from 0% to 81% between regions and species. Our findings show that BEFV was prevalent in the all of the regions tested in our study and provide the first reliable reference regarding BEF surveillance in China., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Bovine viral diarrhea virus (BVDV) is one of the wide distributed pathogenic viruses of livestock and wild animals worldwide. E2 glycoprotein is a major structural component of the BVDV virion and plays a key role in viral attachment to host cells and inducing immune responses against viral infection. In order to gain detailed information of the E2 coding region of BVDV circulating in China, 46 positive samples were tested by RT-PCR for the E2 coding region. The 1122 nt nucleotide sequences of full-length E2 were harvested and analyzed. The results suggested that full-length E2 was an ideal target for BVDV genotyping and divided the domestic BVDV isolates into 9 subgenotypes, namely BVDV-1a, -1b1, -1c, -1d, -1o, -1m, -1p, -1q and BVDV-2a, showing great diversity. The difference of nonsynonymous and synonymous substitution rates (dN-dS) inferred both positive and purifying selection of the E2. However, combination of positive and purifying selection at different points indicated purifying selection within the complete E2. Protein properties analysis based on glycosylation sites and epitope prediction demonstrated that the biological character of E2 among individual BVDV subgenotype was similar, but may alter due to amino acid changes. For the first time, the comprehensive collection of E2 sequences of Chinese BVDV isolates was elucidated, which would provide information for future vaccine design and BVD control in China., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Bovine viral diarrhea virus (BVDV) infects both domestic and wild animals, causing substantial economic losses. In order to investigate possible infection in Bactrian camels in Western China, a total of 56 blood samples were collected from clinically healthy Bactrian camels and tested for BVDV antigens and antibodies using antigen capture enzyme-linked immunosorbent assay (ELISA) and virus neutralization test. The antigen-positive samples (n=17) were further tested for viral nucleic acids by species-specific real-time RT-PCR assays, which showed presence of BVDV-1, but not BVDV-2 nor atypical bovine pestivirus, in the camel samples. Twelve non-cytopathogenic viruses were isolated and genetically typed by sequencing of the 5'untranslated region (5'UTR) and N(pro) coding sequences. Phylogenetic analysis divided the isolates into six known subgenotypes: BVDV-1a, BVDV-1b, BVDV-1c, BVDV-1m, BVDV-1o, BVDV-1p and a putative subgenotype, BVDV-1q. This study provides, for the first time, serological and molecular evidence for natural infection of Bactrian camels in Western China with highly divergent BVDV-1 strains. Further investigations are needed to elucidate the possible roles of Bactrian camels in the epidemiology of BVD in Western China., (Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.)