Deletion Mutants of the Attenuated Recombinant ASF Virus, BA71ΔCD2, Show Decreased Vaccine Efficacy.
Viruses
; 13(9)2021 08 25.
Article
de En
| MEDLINE
| ID: mdl-34578263
ABSTRACT
African swine fever (ASF) has become the major threat to the global swine industry. Lack of available commercial vaccines complicates the implementation of global control strategies. So far, only live attenuated ASF viruses (ASFV) have demonstrated solid protection efficacy at the experimental level. The implementation of molecular techniques has allowed the generation of a collection of deletion mutants lacking ASFV-specific virulence factors, some of them with promising potential as vaccine candidates against the pandemic genotype II ASFV strain currently circulating in Africa, Europe, Asia and Oceania. Despite promising results, there is room for improvement, mainly from the biosafety point of view. Aiming to improve the safety of BA71∆CD2, a cross-protective recombinant live attenuated virus (LAV) lacking the ASFV CD2v gene (encoding ß-glucuronidase as a reporter gene) available in our laboratory, three new recombinants were generated using BA71∆CD2 as a template the single mutant BA71∆CD2f, this time containing the fluorescent mCherry reporter gene instead of CD2v, and two double recombinants lacking CD2v and either the lectin gene (EP153R) or the uridine kinase (UK) gene (DP96R). Comparative in vivo experiments using BA71∆CD2f, BA71∆CD2DP96R and BA71∆CD2EP153R recombinant viruses as immunogens, demonstrated that deletion of either DP96R or EP153R from BA71∆CD2f decreases vaccine efficacy and does not improve safety. Our results additionally confirm ASFV challenge as the only available method today to evaluate the protective efficacy of any experimental vaccine. We believe that understanding the fine equilibrium between attenuation and inducing protection in vivo deserves further study and might contribute to more rational vaccine designs in the future.
Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Vaccins antiviraux
/
Délétion de gène
/
Peste porcine africaine
/
Virus de la peste porcine africaine
/
Anticorps antiviraux
Limites:
Animals
Langue:
En
Journal:
Viruses
Année:
2021
Type de document:
Article
Pays d'affiliation:
Espagne