The future of plague vaccines: hopes raised by a surrogate, live-attenuated recombinant vaccine candidate

Abstract

Yersinia pestis (YP) is the Gram-negative etiological agent of plague against which no commercial vaccine exists to prophylactically prevent a potential outbreak due to natural or bio-warfare/terrorism-mediated causes. The US FDA only recently approved levofloxacin to combat this deadly pathogen. In the article under review, an attenuated, recombinant Salmonella typhimurium ΔphoPQ mutant strain producing YP antigens F1, LcrV and F1–V (fusion protein) from either low-copy pBR or high-copy pUC vectors (maintained by plasmid addiction rather than antibiotic selection pressure) were evaluated for their ability to induce a humoral immune response in both mice and rabbits. This study highlights the need for developing a well-tolerated YP vaccine that, through the oral route, can be readily administered and elicit both mucosal and systemic anti-plague humoral immunity.

Keywords::

• balanced lethal plasmids
• F1
• LcrV antigen
• Salmonella typhimurium-attenuated ΔphoP/Q mutant
• Yersinia pestis vaccine

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.