Immune enhancement by novel vaccine adjuvants in autoimmune-prone NZB/W F1 mice: relative efficacy and safety

We studied phthalate -specific and cross-reactive anti-DNA antibody responses, and parameters associated with the onset of autoimmune disorders. We determined antibody isotype and cytokine/chemokine milieu induced by the above experimental adjuvants relative to alum. Our results indicated that the phytol-derived adjuvant PHIS-01 exceeded alum in enhancing anti-phthalate antibody without much cross reactivity with ds-DNA. Relatively, SIS and PHIS-03 proved less robust, but they were also less inflammatory. Interestingly, these adjuvants facilitated isotype switching of anti-hapten, but not of anti-DNA response. The current study reaffirms our earlier reports on adjuvanticity of phytol compounds and SIS-H in non autoimmune-prone BALB/c and C57BL/6 mice. These adjuvants are as effective as alum also in autoimmune-prone NZB/WF1 mice, and they have little deleterious effects.Although all adjuvants tested impacted cytokine/chemokine milieu in favor of Th1/Th2 balance, the phytol compounds fared better in reducing the onset of autoimmune syndromes. However, SIS is least inflammatory among the adjuvants evaluated.Prophylactic vaccination is considered the most cost-effective way to control diseases; however, in recent years, there has been growing doubts about the benefits of vaccines, primarily because of largely unsupported claims that constituents in vaccine formulations may have long-lasting deleterious effects. These concerns have led to a surge of efforts to redesign vaccines by employment of modern technologies involving recombinant protein antigens, purified allergens, and pathogen-associated offending agents [1]. Alongside, there are new efforts directed to molecularly defined adjuvants or immunostimulants that nonspecifically boost immunogenic potentials of a vaccine. Once considered "immunologists' dirty tricks", adjuvants are garnering considerable attention with regard to their modes of action, safety, and effectiveness. A major focus is to overcome the constra