ABSTRACT
To evaluate avian hepatitis E virus (aHEV) as an RNA vaccine platform, open reading frame 2 (ORF2) of aHEV was replaced by heterologous genes, such as enhanced green fluorescent protein (eGFP) and hemagglutinin (HA)-tag, in aHEV infectious cDNA clones. eGFP and HA-tag replicons were expressed in leghorn male hepatoma (LMH) cells. To confirm expression of the heterologous protein, ORF2 was replaced with the antigenic S1 gene of infectious bronchitis virus (IBV). The IBVS1 replicon was expressed in LMH cells. To our knowledge, this is the first investigation showing potential as a RNA vaccine platform using an aHEV. In the future, it may be used in the development of RNA vaccines against various pathogens.
ABSTRACT
To evaluate avian hepatitis E virus (aHEV) as an RNA vaccine platform, open reading frame 2 (ORF2) of aHEV was replaced by heterologous genes, such as enhanced green fluorescent protein (eGFP) and hemagglutinin (HA)-tag, in aHEV infectious cDNA clones. eGFP and HA-tag replicons were expressed in leghorn male hepatoma (LMH) cells. To confirm expression of the heterologous protein, ORF2 was replaced with the antigenic S1 gene of infectious bronchitis virus (IBV). The IBVS1 replicon was expressed in LMH cells. To our knowledge, this is the first investigation showing potential as a RNA vaccine platform using an aHEV. In the future, it may be used in the development of RNA vaccines against various pathogens.
ABSTRACT
Two infectious bronchitis virus (IBV) K046-12 and K047-12 strains were isolated and the nearly complete genomes of them were sequenced. Sequence comparisons showed that the K046-12 genome was most similar to Korean IBV strains, and the K047-12 genome was most similar to QX-like IBV strains. Phylogenetic analysis showed that nearly all K046-12 and most K046-12 genes were placed in the same cluster as Korean IBV isolates, but the S1 region was placed in the same cluster as Mass-type IBVs. For K047-12, nearly all K047-12 and most K047-12 genes were located in the same cluster as QX-like IBVs, but the M region was located in the same cluster as Korean IBV isolates with K047-12. Recombination analysis confirmed that K046-12 is a recombinant strain with the primary parental sequence derived from Korean IBVs and minor parental sequence derived from Mass-type IBV, and K047-12 is a recombinant strain with the major parental sequence derived from QX-IBV and minor parental sequence derived from Korean IBVs. This study showed that new IBV recombinants are constantly generated among various IBVs, including those used for vaccination. Therefore, genetic analysis of new virus isolates should be performed for effective infectious bronchitis control and appropriate vaccine development.
Subject(s)
Humans , Bronchitis , Genome , Infectious bronchitis virus , Korea , Parents , Recombination, Genetic , VaccinationABSTRACT
The helicase genes and hypervariable regions (HVRs) of three avian hepatitis E viruses (HEVs) detected at three different farms were sequenced and characterized. Two isolates (DW-L and GI-B2) were classified as genotype 2 and one isolate (GR-B) was classified as genotype 1. A phylogenetic tree, based on the helicase gene and HVR nucleotide sequences, revealed the newly detected viruses and other avian HEVs were classified similarly. Unlike previously reported avian HEVs, the DW-L isolate detected in broiler breeders with characteristic lesions of avian HEV had no prolinerich motif in its HVR, suggesting that the proline-rich motif is non-essential for viral replication and infection.
Subject(s)
Agriculture , Base Sequence , Genotype , Hepevirus , Korea , TreesABSTRACT
The helicase genes and hypervariable regions (HVRs) of three avian hepatitis E viruses (HEVs) detected at three different farms were sequenced and characterized. Two isolates (DW-L and GI-B2) were classified as genotype 2 and one isolate (GR-B) was classified as genotype 1. A phylogenetic tree, based on the helicase gene and HVR nucleotide sequences, revealed the newly detected viruses and other avian HEVs were classified similarly. Unlike previously reported avian HEVs, the DW-L isolate detected in broiler breeders with characteristic lesions of avian HEV had no prolinerich motif in its HVR, suggesting that the proline-rich motif is non-essential for viral replication and infection.