Using cross-species vaccination approaches to counter emerging infectious diseases

Abstract

Since the initial use of vaccination in the eighteenth century, our understanding of human and animal immunology has greatly advanced and a wide range of vaccine technologies and delivery systems have been developed. The COVID-19 pandemic response leveraged these innovations to enable rapid development of candidate vaccines within weeks of the viral genetic sequence being made available. The development of vaccines to tackle emerging infectious diseases is a priority for the World Health Organization and other global entities. More than 70% of emerging infectious diseases are acquired from animals, with some causing illness and death in both humans and the respective animal host. Yet the study of critical host-pathogen interactions and the underlying immune mechanisms to inform the development of vaccines for their control is traditionally done in medical and veterinary immunology 'silos'. In this Perspective, we highlight a 'One Health vaccinology' approach and discuss some key areas of synergy in human and veterinary vaccinology that could be exploited to accelerate the development of effective vaccines against these shared health threats.

Fig. 1. Vaccine development pipeline.

The typical vaccine development pipeline is shown, starting from target product profiling to licensure and deployment. The respective stages and approximate costs for veterinary and human vaccines are shown. Although presented as a linear chronological process, some of the different stages of the pipeline for a ‘multispecies’ vaccine can occur in parallel. For instance, the candidate ChAdOx1 RVF vaccine against Rift Valley fever will soon undergo evaluation in human clinical trials in parallel with veterinary development, having been made with the same manufacturing starting material. GMP, good manufacturing practice.

Fig. 2. The heavy chains of bovine antibodies can encode a very long CDR H3, which contrasts with the equivalent CDRs of human, mouse and heavy chain camelid antibodies.

Structures of antigen-binding fragment regions from bovine (BLV1H12, Protein Data Bank (PDB) ID 4K3D; part a), human (PG9, PDB ID 3U2S; part b), mouse (93F3, PDB ID 1T4K; part c) and camelid (VHH-5, PDB ID 5U65 (ref.); part d) antibodies (shown in cartoon representation). Heavy chains are coloured blue and light chains are coloured green. Heavy chain complementarity-determining region 3 (CDR H3; or CDR3 in the case of the camelid antibody) for each structure is coloured orange. PG9 contains a relatively long CDR H3 for human antibodies. Structures were rendered with PyMOL (version 1.8.6.0; Schrödinger LLC).