Nanoparticle formulation for the development of a dog nanovaccine against Cystic Echinococcosis.

Cystic Echinococcosis is a cosmopolitan zoonosis closely linked to poverty and ignorance. It affects both cattle and humans, causing significant losses to both human and animal health. To date, there is no effective way to combat this. Our proposal focused on the formulation of poly (lactic-co-glycolic acid (PLGA) and Eudragit-RSPO polymeric nanoparticles, which are suitable to encapsulate an antigen for oral administration in dogs. This antigen, named EgFABP1, belonging to the family of fatty acid-binding proteins, was isolated from the larval form of the parasite Echinococcus granulosus. Several reports point to proteins from this family from parasitic flatworms as candidates for a successful vaccine, considering the restricted lipid metabolism of these organisms. The encapsulation of the antigen yielded an efficiency higher than 50 %, and the nanoparticles showed the expected size range. In addition, antigen integrity was conserved and the formulation was resistant to artificial gastric and intestinal fluid effects.

Development of an oral nanovaccine for dogs against Echinococcus granulosus.

Dogs are the main source of animal and human cystic echinococcosis caused by the Cestode parasite Echinococcus granulosus. Dog vaccination seems to be a good strategy to control this parasitic disease. Here we present the development of a polymeric nanoparticle-based oral vaccine for dogs against Echinococcus granulosus delivered in enteric-coated capsules. To achieve our target, we encapsulated two recombinant antigens into biodegradable polymeric nanoparticles in the presence of Monophosphoryl lipid A as an adjuvant to ensure efficient delivery and activation of a protective mucosal immune response. The formulated delivery system showed a nanoparticle size less than 200 nm with more than 80 % antigen encapsulation efficiency and conserved integrity and immunogenicity. The nanoparticle surface was coated with chitosan to enhance adhesion to the gut mucosa and a subsequent antigen delivery. Chitosan-coated nanoparticles showed a higher cell internalization in murine macrophages and dendritic cells as well as a higher penetration into Caco-2 cells in vitro. Antigen-loaded nanoparticles were freeze-dried and enteric-coated capsules were filled with the obtained powder. The obtained results show a promising nanoparticles delivery system for oral vaccination.