Novel vaccine strategies against emerging viruses

Abstract

One of the main public health concerns of emerging viruses is their potential introduction into and sustained circulation among populations of immunologically naïve, susceptible hosts. The induction of protective immunity through vaccination can be a powerful tool to prevent this concern by conferring protection to the population at risk. Conventional approaches to develop vaccines against emerging pathogens have significant limitations: lack of experimental tools for several emerging viruses of concern, poor immunogenicity, safety issues, or lack of cross-protection against antigenic variants. The unpredictability of the emergence of future virus threats demands the capability to rapidly develop safe, effective vaccines. We describe some recent advances in new vaccine strategies that are being explored as alternatives to classical attenuated and inactivated vaccines, and provide examples of potential novel vaccines for emerging viruses. These approaches might be applied to the control of many other emerging pathogens.

Attenuated and vectored vaccines protect nonhuman primates against Chikungunya virus

“…Utilizing a truly validated animal model mimicking CHIKV infection in humans, we were able to address how these three different vaccine modalities compare head-tohead in terms of immunogenicity and protective efficacy. Previous studies of CHIKV vaccine candidates in smaller animals (mice) have shown that a large number of CHIKV vaccine candidates are able to provide protective immunity (6,(26)(27)(28). Thus, it was of importance to assess the individual merits of new CHIKV vaccine platforms in a more stringent animal model that more closely resembles a clinical setting.…”

Evolutionary ecology of virus emergence

“…Other efforts rely on computational and bioinformatic tools to identify highly conserved segments of antigenic genes or proteins and their binding epitopes (e.g., Conservatrix, EpiMatrix) . Well‐developed platforms can be modified for speedy use against novel viruses …”

VHSV G glycoprotein major determinants implicated in triggering the host type I IFN antiviral response as DNA vaccine molecular adjuvants

“…Furthermore, DNA vaccines are not affected by anti-vector immunity [7] commonly associated to virus-based vectors used for vaccination. However it is also true that in some cases the development of DNA vaccines present limitations mainly associated to their intrinsic low immunogenicity.…”

“…However it is also true that in some cases the development of DNA vaccines present limitations mainly associated to their intrinsic low immunogenicity. Consequently, research has been conducted to improve the immunogenicity of the vaccines by combining them with adjuvants, either co-administered with the vaccine or encoded in the same plasmid [7]. Up until today, different molecules of the innate immune system [8][9][10], ␤-glucans [11], poly I:C [12][13][14] and other strategies [15][16][17][18] have been used to improve DNA vaccination protection rates.…”