Polymorphism in theLcrV Antigen Enables Immune Escape From the Protection Conferred by an LcrV-Secretingin a Pseudotuberculosis Mouse Model.

Abstract

Yersinioses caused by, andare significant concerns in human and veterinary health. The link between virulence and the potent LcrV antigen has prompted the latter's selection as a major component of anti-vaccines. Here, we report that (i) the group ofspecies encompassingandproduces at least five different clades of LcrV and (ii) vaccination of mice with an LcrV-secretingonly protected againststrains producing the same LcrV clade as that of used for vaccination. By vaccinating with engineered LcrVs and challenging mice with strains producing either type of LcrV or a LcrV mutated for regions of interest, we highlight key polymorphic residues responsible for the absence of cross-protection. Our results show that an anti-LcrV-based vaccine should contain multiple LcrV clades if protection against the widest possible array ofstrains is sought.