Canine distemper virus (CDV) is the causative agent of canine distemper (CD), which is one of the most important infectious diseases affecting wild and domestic carnivores. Vaccination represents an effective approach to prevent CDV infection among domestic carnivores. Canarypox-vectored recombinant CD vaccines (such as Recombitek CDV, PureVax Ferret Distemper, and Merial) with the CDV hemagglutinin (H) and fusion (F) genes can induce a potent immune response in dogs and ferrets. However, the vaccine’s effectiveness varies with the species. In the current study, we developed a highly efficient recombinant canarypox virus termed as “ALVAC-CDV-M-F-H/C5⁻” that contained CDV virus-like particles (VLPs) by using the CRISPR/Cas9 gene editing method, which enabled concurrent expression of the matrix (M), H, and F genes. The recombinant strain provided faster seroconversion than the parent strain among minks as well as provided higher rates of antibody positivity than the parent strain among foxes and minks even before the administration of a second booster vaccination. We demonstrated, for the first time, that the CRISPR/Cas9 system can be applied for the rapid and efficient modification of the ALVAC-CDV-F-H genome and also that a high-dose new recombinant strain that produces CDV VLPs may present good outcomes in the prevention of CD among foxes and minks.

犬瘟热病毒（CDV）是犬瘟热（CD）的病原体，它是影响野生和家养食肉动物的最重要的传染病之一。接种疫苗是预防家庭食肉动物感染CDV的有效方法。金丝雀痘病毒载体的重组CD疫苗（例如Recombitek CDV，PureVax雪貂Distemper和Merial）具有CDV血凝素（H）和融合（F）基因，可以在狗和雪貂中诱导有效的免疫反应。但是，疫苗的有效性随物种而异。在目前的研究中，我们开发了被称为“ALVAC-CDV-MFH / C5高效的重组金丝雀痘病毒^-通过使用CRISPR / Cas9基因编辑方法包含CDV病毒样颗粒（VLP），可以同时表达基质（M），H和F基因。甚至在第二次加强免疫接种之前，该重组菌株在水貂中比亲本菌株提供更快的血清转化，并且在狐狸和水貂中比亲本菌株提供更高的抗体阳性率。我们首次证明了CRISPR / Cas9系统可用于快速有效地修饰ALVAC-CDV-FH基因组，而且产生CDV VLPs的高剂量新重组株可能会在AFP中表现出良好的预后。预防狐狸和水貂身上的CD。