Innate immune system pathways activated by MF59 (MF59-activated pathways)

MF59 is a squalene-based oil-in-water emulsion adjuvant used to enhance the efficacy of vaccines, particularly influenza vaccines for the elderly (O'Hagan et al., 2012). It does not target a single receptor but instead activates a complex network of innate immune pathways to create a local "immunocompetent environment" at the injection site (Seubert et al., 2008). This process involves the rapid induction of chemokines like CCL2 and CXCL8, which recruit immune cells such as monocytes and dendritic cells to the site of injection (Mosca et al., 2008). These recruited cells efficiently take up the vaccine antigen and transport it to the draining lymph nodes for presentation to T and B cells. At the molecular level, MF59-mediated activation involves the MyD88 adapter protein and the NLRP3 inflammasome, though it operates independently of most Toll-like receptors (O'Hagan et al., 2012). By stimulating these innate pathways, MF59 significantly boosts the magnitude, breadth, and persistence of the adaptive immune response.

Other names

MF59 adjuvant signalingMF59-induced immunocompetent environmentSqualene-based emulsion immune activationMF59 mechanism of action

MF59 induces a local "immunocompetent environment" by stimulating the production of chemokines such as CCL2, CCL3, and CXCL8, which recruit monocytes and dendritic cells to the injection site (Seubert et al., 2008; Mosca et al., 2008). It also activates the NLRP3 inflammasome and utilizes MyD88-dependent signaling pathways to enhance antigen uptake and presentation to T cells (O'Hagan et al., 2012).