VACCINOLOGY, IMMUNOLOGY, AND COMPARATIVE PATHOGENESIS OF MEASLES IN THE QUEST FOR A PREVENTATIVE AGAINST AIDS

Current approaches to the prevention and control of AIDS by vaccines a nd by chemotherapy have failed to provide satisfactory solutions to th is important medical problem and have failed, in addition, to provide definitive guidelines for future research endeavor. Vaccine research m ust and will continue but it is possible that a safe and effective vac cine may never be developed and it may be timely to explore, in additi on, alternative means for immunological intervention in AIDS. Both imm unoprophylactic and immunotherapeutic efforts might be assisted by man ipulating the T helper 1 (Th1) and T helper 2 (Th2) subsets of CD4(+) T helper cells, which is therefore worthy of exploration. Selective co ntrol of immune response by the two T helper subsets is by release of different cytokines that promote either cellular or humoral immunity, the latter of which may be associated with inappropriate immune respon ses and with immune dysfunction. Discovery of the Th1 and Th2 subsets and definition of the cytokines they release provide a new avenue towa rd possible development of a safe and effective vaccine and an approac h, in addition, to correction of immune dysfunction by selective cytok ine administration or by cytokine ablation by antagonists or antibodie s. AIDS pathogenesis and immune dysfunction are complex and understand ing them may be overwhelmed by an excess of possibilities. Simplificat ion of the endeavor might benefit from comparative studies of the path ogenesis of measles, in which there also is immune deficiency but usua lly with spontaneous viral clearance, reversal of immune dysfunction, and total recovery. In addition, measles presents as a single disease and is caused by an antigenically stable virus. Identification of the process whereby measles immunodeficiency is spontaneously reversed mig ht be of importance in attempting to devise means for similar reversal in AIDS.