First, a vaccine would need to be rigorously shown to induce full protection, rather than inducing partial protection which could lead to unrecognized latent infection. Therefore, such a vaccine would

need to a) prevent chancre development associated with primary disease and the lesions associated with secondary disease to abolish transmission of T. pallidum and HIV and b) inhibit treponemal dissemination throughout the host to prevent corresponding disease progression and establishment of CS. Second, the vaccine candidate(s) would need to be effective in generating a Th1 response and opsonic antibodies due to the critical role that opsonophagocytosis plays in T. pallidum clearance during infection. And third, the vaccine candidate(s) must be selected to ensure the vaccine is broadly protective against many T. pallidum strains. These complex requirements are very unlikely to be met using a single treponemal protein, and thus it is probable ABT-888 cost that an effective syphilis vaccine will constitute a multi-component formulation. After almost a century of research, significant insight has been provided

into the correlates of protection in the rabbit model. However, successful vaccine development will depend upon extending our understanding GDC-0068 chemical structure of the correlates of protection in humans by fostering exchange of information and samples between the basic research laboratories and the clinics. Development of appropriate and effective adjuvants is essential and is likely to require the participation

of industry. Within the realm of research there needs to be the application of large-scale “omics” experimental approaches and data analyses to enhance our understanding of factors such as differential gene and protein expression among T. pallidum subspecies and T. pallidum subspecies pallidum strains. And, most importantly, there needs to be an enhanced effort to conclusively determine the identity of surface-exposed antigens. This includes the OMPs, but also requires that the field pursue non-protein antigens including membrane lipids and post-translational modifications such as glycosylation or methylation others of exposed proteins. The field has been focussing on the “easier” protein antigens, perhaps at its peril. The accomplishment of these goals will require attracting a larger number of trained syphilis basic scientists to the field and a commitment of continual and enhanced training and research support that is commensurate with technical barriers and the high cost of performing T. pallidum research. The successful development of vaccines for a developing world market is challenging, as the average timeline for development of a new vaccine is 8-18.5 years at an estimated cost of $200–$900 million [97]. However, there is already a significant precedent for the support of pharmaceutical and biotechnology companies in the development of vaccines for diseases that disproportionately affect people in the developing world.