Packaged replicons of bovine viral diarrhea virus are capable of inducing a protective immune response

Abstract

Bovine viral diarrhea virus (BVDV) replicons with deletions within the capsid, E(RNS) or E1 encoding region were constructed and efficiently packaged with a helper cell line. High titres of packaged replicons were observed as early as 24 h after transfection, whereas no virus progeny could be detected after transfection of non-complementing cells. Infection of bovine cell cultures with rescued viruses resulted in one cycle of replication without release of infectious virus particles, and no genetic reversion of the generated viruses was detected. Packaged replicons with a deletion within the capsid-coding region were characterized in vivo in immunization and challenge trials. Following immunization of calves with the replication-deficient virus, neither virus shedding nor viremia was detected. After challenge infection with virulent BVDV, all vaccinates were completely protected from disease as measured by the absence of viremia and shedding of challenge virus, which indicated that a 'sterilizing immunity' could be induced with the generated replication-deficient packaged replicons.

Characterization of Essential Domains and Plasticity of the Classical Swine Fever Virus Core Protein

“…Assay detection limit is 100 FFU/ml. Core protein with an internal deletion of 43 amino acids (37). Thus far, pestiviral Core protein has been functionally characterized with regard to nucleic acid binding, RNA chaperone activity, and its ability to replace the RNA-binding domain of Sindbis virus Capsid protein (15,32).…”

“…Mapping of the important amino acids at the Core C terminus by truncations within the infectious cDNA is complicated by its overlap with the signal peptide and possible interference with translocation of the structural glycoproteins. Therefore, a transcomplementation experiment, in analogy to that of Reimann et al (37), was designed. For this approach, we constructed p447 ⌬169-246 , which lacked about 90% of the Core coding sequence (amino acids 169 to 246).…”

“…However, infectious virus could be recovered by providing Core along with other structural proteins in trans (37). Thus, the importance of pestiviral Core protein for the generation of infectious virus particles is known, but no reports exist on the functional organization of this protein.…”

Prevalence of antibodies to Bovine Viral Diarrhea Virus (BVDV) in blood and milk serum in dairy cattle in Kars district of Turkey

“…The virus is classified into two main genotypes (BVDV-1 and BVDV-2), based on antigenic and genetic properties, with each genotype further divided into either cytopathic or noncytopathic biotypes, based on how they replicate in cell culture (Ridpath, 2013). BVDV is a multi-system viral infection which causes significant economic losses and is characterized by clinical and pathological variations that range from reproductive disorders and congenital abnormalities to abortion, birth of calves with persistent infections , early embryo death and mummification (Zoth and Taboga, 2006;Reimann et al, 2007). Persistently infected (PI) animals continually shed a large amount of virus in their body fluids.…”

Mutation of Cysteine 171 of Pestivirus ErnsRNase Prevents Homodimer Formation and Leads to Attenuation of Classical Swine Fever Virus

“…Deletion of the E rns -coding region from the viral genome resulted in replicons capable of autonomous RNA replication but unable to produce infectious virus particles (42,60). In addition to its function as a structural protein, E rns has the unique feature of containing an intrinsic RNase activity (14,18,49,61), whose active site exhibits sequence homology with RNase Rh, a member of the T 2 /S RNase superfamily (17,18).…”