Immune system via adjuvant effect

Adjuvants are substances added to vaccines or immunotherapies that *enhance the body's immune response* against the delivered antigen. They function by activating innate immune cells (such as antigen-presenting cells—APCs), promoting cytokine and chemokine production, improving antigen uptake and presentation, and stimulating both humoral and cellular arms of adaptive immunity. This adjuvant effect enables weaker antigens to become strongly immunogenic, directs the type (Th1 vs Th2 vs Th17) and durability of the immune response, and can reduce the antigen dose required for efficacy. Common adjuvant classes include aluminum salts (alum), squalene emulsions (MF59, AS03), TLR agonists (CpG, MPLA), and others; each has a distinct safety profile and mechanism of enhancing immune function[1][2][3][5][7].

Activation of innate immune cells; Enhancement of antigen presentation; Induction of cytokines and chemokines; Promotion of adaptive immune responses; Creation of an immunocompetent environment at the injection site