Selection of adjuvants for vaccines targeting specific pathogens

ABSTRACT

Introduction: Adjuvants form an integral component in most of the inactivated and subunit vaccine formulations. Careful and proper selection of adjuvants helps in promoting appropriate immune responses against target pathogens at both innate and adaptive levels such that protective immunity can be elicited.

Areas covered: Herein, we describe the recent progress in our understanding of the mode of action of adjuvants that are licensed for use in human vaccines or in clinical or pre-clinical stages at both innate and adaptive levels. Different pathogens have distinct characteristics, which require the host to mount an appropriate immune response against them. Adjuvants can be selected to elicit a tailor-made immune response to specific pathogens based on their unique properties. Identification of biomarkers of adjuvanticity for several candidate vaccines using omics-based technologies can unravel the mechanism of action of modern and experimental adjuvants.

Expert opinion: Adjuvant technology has been revolutionized over the last two decades. In-depth understanding of the role of adjuvants in activating the innate immune system, combined with systems vaccinology approaches, have led to the development of next-generation, novel adjuvants that can be used in vaccines against challenging pathogens and in specific target populations.

KEYWORDS:

• Adjuvants
• mechanism of action
• pathogen
• systems vaccinology
• immunity

Article highlights

• Identification of new PRRs and their agonists are expected to lead to the identification of more adjuvants; in particular, PRR agonists in combination adjuvants hold great promise.

• Systems vaccinology will provide a better understanding of the mode of action of adjuvants and allow identification of unique biomarkers of adjuvanticity.

• There are many pathogens for which host–pathogen interactions have not been characterized in detail. Such knowledge on host–pathogen interaction combined with the mechanism of action of adjuvants will lead to the use of specific adjuvants in vaccines against distinct pathogens.

Acknowledgments

The authors like to thank all the current and previous members from the laboratory as well as the animal care facility at VIDO-InterVac, University of Saskatchewan, Canada for their contribution. This is VIDO-InterVac manuscript no 842.

Declaration of interest

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.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

Publication of this manuscript is supported by grant MOP 42436 from the Canadian Institutes of Health Research (CIHR).