In addition, we further confirmed the apparent lack of antiviral or inflammatory responses to infection with PRV by examining the gene expression of three immune-associated proteins: the classical interferon viral response protein Myxovirus resistence protein 1 (Mx), the inflammatory cytokine Interleukin 1β (IL-1β), and the inflammatory chemokine Interleukin 8 (IL-8) at 21 dpc PRV. The gene discussed is MX1; the disease is infection.