Valuable systemic immunity for lambs immunized intranasally with sheep pox virus encapsulated in chitosan nanoparticles

Abstract

Sheep pox virus (SPXV) from the Poxviridae family causes a highly contagious and drastic disease in sheep. Periodic outbreaks are mainly confined to Asia and Africa, however also new emergence has recently been reported in other parts of world. The necessity for a new vaccine is required to achieve effective and high coverage vaccination for sheep flocks. For efficient mucosal vaccine delivery, chitosan nanoparticles with mucoadhesive properties have the ability to open tight junctions between epithelial cells, and facilitate antigen uptake. Current study was conducted to evaluate protective efficacy of live attenuated sheep pox virus encapsulated in chitosan nanoparticles (LSPV-CS-NPs). Thirty immunological naïve lambs aliquot divided into lambs given Phosphate buffer saline as control group, second group with blank chitosan nanoparticles, third group intranasal vaccinated with LSPV-CS-NPs, fourth group subcutaneously vaccinated with  LSPV-CS-NPs and fifth group contains lambs immunized with commercial vaccine subcutaneously. Post immunization, by using ELISA technique, the sera was investigated for specific sheep pox virus IgG and IgA, the assay showed significantly increasing in third group compared to other groups over the course of eight weeks. Altogether, the CS-NPs could be considered as an efficient intranasal LSPV delivery system for nasal vaccines to enhance systemic immunity, therefor this approach has an immense application promise.