Immunization with avian metapneumovirus harboring chicken Fc induces higher immune responses

•aMPV grown in Vero-cFc incorporated host derived chimera Fc into the aMPV virions.•aMPV-cFc group induced higher level of antibodies and inflammatory cytokines.•The aMPV-cFc group also generated the highest neutralizing antibody response.•After challenges experiment, aMPV-cFc induced higher protection in chickens.•Greater ability of aMPV Fc to aMPV presented it as a possible vaccine candidate.

In this study, we evaluated the immune responses of avian metapneumovirus harboring chicken Fc molecule. Stable Vero cells expressing chicken Fc chimera on its surface (Vero-cFc) were established, and we confirmed that aMPV grown in Vero-cFc incorporated host derived chimera Fc into the aMPV virions. Immunization of chicken with aMPV-cFc induced higher level of antibodies and inflammatory cytokines; (Interferon (IFN)-γ and Interleukin (IL)-1β) compared to those of aMPV. The increased levels of antibodies and inflammatory cytokines in chicken immunized with aMPV-cFc were statistically significantly (p < 0.05) to that of aMPV and control. The aMPV-cFc group also generated the highest neutralizing antibody response. After challenges, chickens immunized with aMPV-cFc showed much less pathological signs in nasal turbinates and trachea so that we could confirm aMPV-cFc induced higher protection than that of aMPV. The greater ability of aMPV harboring chicken Fc to that of aMPV presented it as a possible vaccine candidate.