Prostaglandin A1 inhibits the replication of bovine viral diarrhea virus

ABSTRACT Bovine viral diarrhea virus can cause acute disease in livestock, leading to economic losses. We show that Prostaglandin A1 inhibits bovine viral diarrhea virus replication in Madin-Darby bovine kidney cells (94% inhibition using 5 µg/mL). Light and electron microscopy of infected cells shows that Prostaglandin A1 also prevents virus-induced vacuolization, but at higher concentrations (10 µg/mL).

Use of homologous recombination in yeast to create chimeric bovine viral diarrhea virus cDNA clones

Abstract The open reading frame of a Brazilian bovine viral diarrhea virus (BVDV) strain, IBSP4ncp, was recombined with the untranslated regions of the reference NADL strain by homologous recombination in Saccharomyces cerevisiae, resulting in chimeric full-length cDNA clones of BVDV (chi-NADL/IBSP4ncp#2 and chi-NADL/IBSP4ncp#3). The recombinant clones were successfully recovered, resulting in viable viruses, having the kinetics of replication, focus size, and morphology similar to those of the parental virus, IBSP4ncp. In addition, the chimeric viruses remained stable for at least 10 passages in cell culture, maintaining their replication efficiency unaltered. Nucleotide sequencing revealed a few point mutations; nevertheless, the phenotype of the rescued viruses was nearly identical to that of the parental virus in all experiments. Thus, genetic stability of the chimeric clones and their phenotypic similarity to the parental virus confirm the ability of the yeast-based homologous recombination to maintain characteristics of the parental virus from which the recombinant viruses were derived. The data also support possible use of the yeast system for the manipulation of the BVDV genome.

O polietilenoglicol aumenta a penetração do vírus da diarréia viral bovina, do vírus da estomatite vesicular e do vírus sincicial respiratório bovino em células de cultivo / Polyethylene glycol increases the penetration of bovine viral diarrhea virus, vesicular stomatitis virus and bovine respiratory syncytial virus in cultured cells

A baixa eficiência de penetração de alguns vírus em células de cultivo pode representar uma dificuldade para o isolamento e a multiplicação viral in vitro. No presente estudo investigou-se o efeito do polietilenoglicol (PEG) na replicação de sete vírus bovinos em células de linhagem de rim bovino (MDBK). A eficiência de penetração e replicação foi mensurada pela contagem do número de placas virais produzidas em tapetes celulares, após adsorção do inóculo viral (100 DICC50 mL-1) com ou sem a adição de PEG a 5 por cento (peso molecular 6.000). A adição de PEG ao inóculo resultou em aumentos significativos do número de placas para o vírus da diarréia viral bovina (BVDV) (aumento de 3,4 vezes), vírus da estomatite vesicular (VSV) (2,2 vezes) e vírus respiratório sincicial bovino (BRSV) (1,5 vezes). A adição de PEG não produziu aumento significativo no número de placas dos herpesvírus bovinos 1, 2 e 5 (BoHV-1, BoHV-2 e BoHV-5). Por outro lado, o PEG produziu uma redução do número de placas (1,4 vezes) produzidas pelo vírus da parainfluenza bovina (bPI-3V). A adição de PEG a 5 por cento também aumentou a sensibilidade de detecção (entre 10 e 100 vezes) do BVDV no soro de três bezerros persistentemente infectados. Para o BRSV, a adição de PEG aumentou em duas vezes a sensibilidade do isolamento viral de secreções nasais de duas ovelhas infectadas experimentalmente. Esses resultados demonstram que o PEG aumenta a eficiência de infecção do BVDV, VSV e BRSV em células de cultivo, podendo ser utilizado para aumentar a sensibilidade de detecção desses vírus em amostras clínicas (isolamento viral) e/ou, para aumentar os títulos de vírus produzidos em cultivo celular.

The low efficiency of penetration of some viruses in cultured cells may represent an obstacle for viral isolation and/or viral multiplication in tissue culture. This study investigated the effect of polyethylene glycol (PEG) on the penetration and replication of seven bovine enveloped viruses in culture cells. Penetration efficiency was measured by counting the number of viral plaques produced in bovine kidney cells (MDBK). The addition of 5 percent PEG (molecular weight 6.000) to the viral inoculum containing 100 TCID50 mL-1 (tissue culture median infectious dosis) of each virus, during adsorption for 2h at 37ºC, resulted in a significant increase in the number of plaques for bovine viral diarrhea virus (BVDV) (increase of 3.4-fold), vesicular stomatitis virus (VSV) (2.2-fold) and bovine respiratory syncytial virus (BRSV) (1.5-fold). The addition of 5 percent PEG to the inoculum of bovine herpesviruses 1, 2 and 5 (BoHV-1, BoHV-2 and BoHV-5) did not increase the number of viral plaques. On the other hand, PEG produced a reduction in the number of plaques by bovine parainfluenza virus (bPI-3V) (1.4-fold). Furthermore, the addition of 5 percent PEG produced a 10- to 1000-fold increase in the sensitivity of BVDV detection in the serum of three persistently infected calves; and doubled the sensitivity of detection of BRSV in nasal secretions of two experimentally infected sheep. These results demonstrate that PEG enhances the efficiency of infection by BVDV, VSV and BRSV in cultured bovine cells and therefore may be used to increase the sensitivity of virus detection in clinical samples (viral isolation), and/or to increase virus titers in cell cultures.