However, substitution of both E<sup>rns</sup> and E2 in the C-strain backbone abolished fever response, and the chimeric virus did not show adaptation in rabbits as demonstrated by lack of viral RNA and E2 protein expression in the spleen and weak antibody responses.
The E2 protein in classical swine fever (CSF) virus (CSFV) is the major virus structural glycoprotein and is an essential component of the viral particle.
As induction of a protective immune response relies on virus-neutralizing antibodies against E2 protein of CSF virus (CSFV), the most promising DIVA strategy is based on detection of E<sup>rns</sup> -specific antibodies in infected swine.