(680c) Rational and Combinatorial Design of Chemical Mixtures for Transcutaneous Vaccination

Transcutaneous immunization, topical application of vaccines on skin, provides several advantages over needle based immunization. However, simple topical application of vaccines does not generate sufficient immune response due to limited transport of vaccines across the stratum corneum of skin. Here we report that chemical mixtures can enhance the immunogenicity of topically applied antigens. Six hundred distinct chemical mixtures were screened systematically for their potency (delivery of antigen) in vitro. A selected subset of these formulations was subsequently tested for their adjuvanticity (activation of immune response) in vitro. Lead formulations were tested in vivo for their ability to generate antibody titers against topically applied ovalbumin, a model antigen. Lead formulations were significantly more effective in generating anti-ovalbumin IgG titers. Our results demonstrate that chemical formulations can be successfully used to deliver antigens and that such formulations can be rationally designed by combinatorial screening of individual chemical components.