Antigen presenting cells (APC) present antigen to naive T cells and depending on the nature of co-stimulating signals and secreted cytokines, the transition of naive T cell to maturated T helper cells is initiated. Depending on the nature of the stimulating signals, humoral and cell mediated immune response is activated to different extent. The use of Adjuvant Systems like AS04 amplifies and modulates the specific information provided by antigens to the immune system. More memory B-cells and antibodies can be generated.
Figure 2: Enhanced activation of immune system.