171187 20260515163945.0 doi 10.3390/v18040462 sideral 149251 ART-2026-149251 eng Gómez, Álex Universidad de Zaragoza (orcid)0000-0002-9723-9004 In Vitro Antiviral Properties of Two Recombinant Sendai Virus Vectors Encoding ORFV 011 and ORFV 059 Genes 2026 Orf virus (ORFV) is a globally distributed zoonotic parapoxvirus that causes a highly contagious mucocutaneous disease in small ruminants. Despite the urgent demand for vaccination-based control, no licensed vaccines are currently available universally. In this study, we generated two recombinant Sendai virus (SeV) vectors expressing ORFV 011 (rSeV-GFP-B2L) and ORFV 059 (rSeV-GFP-059) genes and evaluated their ability to stimulate antiviral responses in vitro. Following the transduction, we assessed transgene expression, innate immune activation, induction of interferon-stimulated genes (A3Z1, OBST2, SAMHD1), and antiviral activity. Both vectors significantly upregulated pattern recognition receptors (TLRs, RIG-I) and type I interferon (IFN-β) genes, with rSeV-GFP-059 inducing the strongest response. Remarkably, OBST2 was robustly upregulated, suggesting a potential role in restricting ORFV replication. Antiviral activity assays revealed a marked reduction in ORFV DNA copies and a mild decrease in ORFV RNA transcription in rSeV-GFP-059-transduced cells, particularly at later time points, accompanied by complete abrogation of the typical cytopathic effect. Collectively, these results demonstrate that SeV-based vectors, particularly rSeV-GFP-059, efficiently prime antiviral immunity and suppress ORFV replication, establishing a promising platform for further in vivo vaccine evaluation in sheep. Access copy available to the general public Unrestricted info:eu-repo/semantics/openAccess by https://creativecommons.org/licenses/by/4.0/deed.es info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Glaria, Idoia Moncayola, Irati Puzol, Leonor Arriazu, Laura Calero, Ainhoa de Blas, Ignacio Universidad de Zaragoza (orcid)0000-0002-1204-4356 Nazábal, Mikel Hualde, Itziar Lee, Benhur Luján, Lluís Universidad de Zaragoza (orcid)0000-0002-2053-9842 Amann, Ralf Echeverría, Irache Reina, Ramsés 1009 773 Universidad de Zaragoza Dpto. Patología Animal Área Sanidad Animal 18, 4 (2026), 462 [17 pp.] VIRUSES-BASEL VIRUSES-BASEL 1999-4915 2349123 http://zaguan.unizar.es/record/171187/files/texto_completo.pdf Versión publicada 2387902 http://zaguan.unizar.es/record/171187/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:171187 articulos driver 2026-05-15-14:54:40 ARTICLE