Memory T cells and B Cells are the foundation of vaccination success. In addition, immunization activates CD4+ (indirectly cytotoxic via cytokine and support of Cd8+ production) and cytotoxic CD8+ subsets. Similar to actual infection, vaccine administration elevates the antibody IgM and later IgG (with an apex of 30 days), the former for immediate protection and the latter for lasting defense.
Using the mechanism of the classic live attenuated vaccine, immunization recruits macrophages, lymphocytes and dendritic cell APCs to the site of injection (or alternate ROA), and sends them to lymph-rich areas. Next, both antigen-specific and generalized B-cell proliferation occurs and circulates. Memory B cells will be differentiated into plasma B cells upon antigen introduction. The T-cell effector response eliminates the organism using a MHC-mediated function, activating the correct direct (Th2/Th1) cytotoxic response or cytokinetic elimination cascade.
Vaccines are important for both herd immunity and personal health. They have a high degree of efficacy and low degree of risk. Live attenuated, toxoid, and recombinant vaccines are all combined into one group insofar as mechanism of action, when in fact they variably affect TLRs and IgA.
Immunization is helpful to healthy patient populations as a general rule, especially when administered at the beginning of the life. Several classes have diminishing efficacy, however; and must be boosted. In the author’s opinion, more studies researching susceptible adverse event immunophenotypes and more neutral adjuvants.