Immunogenicity and protective efficacy of virosome based vaccines against Newcastle disease.

Virosome based vaccines against Newcastle disease (ND) were prepared and evaluated for their immunogenicity and protective efficacy in chickens. Envelop of Newcastle disease virus (NDV) was solubilised with Triton X-100 to yield virosomes which were later on encapsulated in poly-lactide-co-glycolide (PLG) microspheres. The birds were immunized intranasally with virosomes or PLG microspheres encapsulated virosomes, and efficacy of these preparations was compared with commercial LaSota vaccine. The preparations protected the chickens against virulent virus challenge infection, however the microencapsulated virosome vaccine gave slightly lesser degree of protection than non encapsulated counterpart. The humoral and cell mediated immune response generated as well as the protection afforded by virosome preparations were found to be comparable with LaSota vaccine. The results substantiate the potential of virosome based vaccines to provide high level of immunity and protection against Newcastle disease.