Developing Antiviral Vaccines Based on Attenuated Salmonella

Attenuated Salmonella strains are a promising gene delivery vector in the development of vaccines targeting various human diseases. For example, the Ty21a vaccine is a Salmonella-based vaccine that elicits a robust local, cellular, and systemic immune response against Salmonella typhi infection. Human immunodeficiency virus (HIV) is responsible for the AIDS pandemic and requires lifelong treatment to manage. Human papillomavirus (HPV) is the cause of the vast majority of cervical cancer cases in the global population. Influenza is a seasonal, pandemic virus that can lead to high death tolls in humans and livestock and considerable financial losses. In this review, we outline current methods of protection and treatment for HIV, HPV, and influenza, as well as how a versatile Salmonella-based gene delivery vector's mechanism of action can lead to immunity. We also describe several studies that utilize many of these Salmonella-based vector vaccines to provide protection against infection with these viruses, as many of these Salmonella-based vectors exhibit different factors that may enhance their gene delivery, immune responses, and post-delivery clearance out of host cells. Finally, we discuss the benefits and drawbacks of using Salmonella-based vaccines and future directions for these vaccine candidates, as well as the implications of introducing these vaccines into the current landscape.