RESUMO
Classical swine fever (CSF) is a devastating infectious disease caused by classical swine fever virus (CSFV). The screening of CSFV-specific ligands is of great significance for diagnosis and treatment of CSF. Affinity selection from random peptide libraries is an efficient approach to discover ligands with high stability and specificity. Here, we screened phage ligands for the CSFV E2 protein from f8/8 landscape phage display library by biopanning and obtained four phage clones specific for the E2 protein of CSFV. Viral blocking assays indicated that the phage clone displaying the octapeptide sequence DRATSSNA remarkably inhibited the CSFV replication in PK-15 cells at a titer of 10(10) transduction units, as evidenced by significantly decreased viral RNA copies and viral titers. The phage-displayed E2-binding peptides have the potential to be developed as antivirals for CSF.
Assuntos
Antivirais/farmacologia , Vírus da Febre Suína Clássica/efeitos dos fármacos , Biblioteca de Peptídeos , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Antivirais/química , Antivirais/metabolismo , Bacteriófagos/genética , Bacteriófagos/metabolismo , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/genética , Vírus da Febre Suína Clássica/fisiologia , Avaliação Pré-Clínica de Medicamentos , Ligantes , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Ligação Proteica , Suínos , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is a highly contagious swine disease leading to significant economic losses worldwide. Vaccines are widely used to control the disease, and no CSFV-specific antivirals are currently available. To facilitate anti-CSFV molecule discovery, we developed a reporter virus CSFV-N(pro)Fluc stably expressing the firefly luciferase (Fluc) gene in the N(pro) gene. The reporter virus enabled more sensitive and convenient detection of the N(pro) protein expression and the viral replication by luciferase reporter assay than by traditional methods. The CSFV N(pro) protein was detectable as early as 4.5h post-infection. As a proof-of-concept for its utility in rapid antiviral screening, this reporter virus was used to quantify anti-CSFV neutralizing antibodies of 50 swine sera and to assess 12 small interfering RNAs targeting different regions of the CSFV genome. The results were comparable to those obtained by traditional methods. Taken together, the reporter virus CSFV-N(pro)Fluc represents a useful tool for rapid and quantitative screening and evaluation of antivirals against CSFV.