Oil-in-Water Emulsion Adjuvants (AS03 and MF59)

Oil-in-water emulsion adjuvants such as AS03 and MF59 are complex formulations used to enhance immune responses in vaccines. They consist of tiny droplets of oil dispersed in water, stabilized by surfactants. These adjuvants boost the magnitude and quality of adaptive immune responses, allowing for antigen dose sparing and a more rapid onset of immunity. They primarily stimulate innate immunity locally at the injection site, leading to superior adaptive responses systemically, inducing potent antibody production while also supporting robust T-cell mediated protection.

Other names

AS03MF59Squalene-based adjuvantAdjuvant System 03Oil-in-water adjuvant

Oil-in-water emulsions activate local innate immunity, increase antigen uptake by APCs, and enhance antigen presentation in draining lymph nodes, leading to robust activation of B cells and T cells, resulting in strong humoral and cellular immune responses.