Molecular and cellular basis of interleukin 12 activity in prophylaxis and therapy against infectious diseases.

A major goal for immunologists dealing with infectious diseases is the development of vaccines and immunotherapies that will protect patients against infection or the undesired effects of immune responses elicited by pathogens. Studies defining the function of different cytokines have contributed to the progress of new strategies to manipulate the immune response. Recent studies have demonstrated that interleukin 12 (IL-12) is a key cytokine for promoting cell-mediated immunity and initiating resistance to infection. Because IL-12 is a potent stimulator of host defense against a variety of pathogens, it holds great promise for therapeutic use. In addition, IL-12 antagonists protect the host against immunopathology and death caused by an excessive cellular immune response that can occur during acute microbial infections.