Audiuvare – to help.
Although the word “adjuvant” might suggest a group of earnest lab assistants, adjuvants are ingredients that provoke a stronger immune response to vaccines. These supplementary scientists encourage more local and systemic reactions to the vaccine and have done so for almost a century. They first appeared as contaminants in aluminium vessels, and are now a deliberate part of vaccine production.
An interview between Kristen Kresge Abboud and Dr Bali Pulendran for IAVI report explored the role of adjuvants in mRNA vaccines. They reflected that adjuvants are “one way to augment the durability of vaccine-induced immunity”. Dr Pulendran refers to adjuvants as a “sort of witches’ brew”. Spooky. His lab focuses on demystifying adjuvants with knowledge of innate immunity and the pathways they stimulate. The end goal of these investigations will be “rational” adjuvant design that captures the “magic of these witches’ brews”
Using the Covid-19 mRNA vaccines as a case study, Dr Pulendran discusses their efficacy considering “durability is related to signalling in the innate immune system”. Acknowledging that the vaccines are “truly transformative”, he suggests that the antibody response is short-lived, hence the booster requirements in the face of new variants.
He recalls that studies demonstrated that the yellow fever vaccine engaged multiple receptors within the innate immune system, and that this “synergistic engagement” was essential to antibody responses. Consequently, the next step was the development of a synthetic vaccine or virus that captured the “essential features” of this vaccine to stimulate “durable immunity”.
More recently, they did the same thing to the Pfizer/BioNTech mRNA vaccine and found that the T-cell responses were “more durable than the antibody responses”. The question, then, was can we “adjuvant the mRNA vaccine so it doesn’t suppress protein production, but it still provides the innate signalling required to get durable responses”? Currently several adjuvants are being explored, without clarity on which will be the best, but a recent subunit vaccine, adjuvanted with AS03, was approved after studies assessing a range in non-human primates.
For a whole day of adjuvant discussion come to the pre-congress adjuvant workshop at the World Vaccine Congress in Barcelona October 2022: book your tickets here.