Rabies continues to poses serious threats to the public health in many countries. The development of novel inexpensive, safe and effective vaccines has become a high priority for rabies control worldwide. We previously generated a novel recombinant rabies vaccine by cloning rabies virus glycoprotein into a chimpanzee adenoviral vector, termed ChAd68-Gp. The present study evaluated the immune responses and protection afforded by this vaccine in beagle dogs. The results demonstrated that intramuscular immunization with both low-dose and high-dose of ChAd68-Gp induced strong immune responses and provided complete protection in beagles even at low-dose. However, when administered orally, high-dose vaccination was protective while low-dose vaccination was ineffective. Further investigation indicated that the low-pH value of gastric juice in the stomach of beagles might decompose the adenovirus. Therefore, suitable formulation for adenovirus-based oral vaccine should be considered and developed. The chimpanzee adenovirus-vectored rabies vaccine ChAd68-Gp warrants extensive test for clinical application.
Keywords: Adenoviral vector; Beagle; ChAd68-Gp; Immune responses; Rabies vaccine.
Copyright © 2019 Elsevier Inc. All rights reserved.