MF59-mediated innate immune activation

MF59-mediated innate immune activation refers to the complex series of cellular and molecular events triggered by the squalene-based oil-in-water emulsion adjuvant MF59 (O'Hagan et al., 2012). Upon injection, MF59 creates a local immunocompetent environment by stimulating the release of endogenous danger signals, most notably adenosine triphosphate (ATP), from resident cells (Vono et al., 2013). This ATP release triggers the activation of the NLRP3 inflammasome, leading to the processing and secretion of pro-inflammatory cytokines such as IL-1β and IL-18 (Seubert et al., 2008). Additionally, MF59 induces the rapid production of chemokines like CCL2, CCL3, and CXCL10, which facilitate the recruitment of various innate immune cells, including monocytes, macrophages, and granulocytes, to the injection site (De Gregorio et al., 2008). These recruited cells efficiently take up vaccine antigens and migrate to draining lymph nodes, where they differentiate into mature dendritic cells and initiate a potent adaptive immune response (O'Hagan et al., 2012). This mechanism is distinct from many other adjuvants as it does not rely on direct activation of Toll-like receptors (TLRs) but rather on the orchestration of a broad innate immune network (Vono et al., 2013).

Other names

Innate immune cells and pathways activated by MF59MF59 adjuvant signalingMF59-induced innate responseMF59 mechanism of action

MF59 acts as a vaccine adjuvant by creating a local immunocompetent environment, inducing the release of endogenous danger signals like ATP, and activating the NLRP3 inflammasome to promote the recruitment and activation of antigen-presenting cells.