We would like to develop a tolerogenic nanoparticle vaccine for the prevention of Type 1 Diabetes. Nanoparticles will contain both an antigen that will be presented by lymph node dendritic cells and a tolerogenic molecule that will induce tolerance to the antigen presented. Several tolerogenic molecules will be evaluated in a mouse tail allograft model to optimize the ability of the particles to induce local immune suppression. Then, the effect of antigen specificity on dendritic cell response in vivo will be determined using a model antigen, ovalbumin. Finally, the tolerogenic nanoparticles will include the self-antigen, proinsulin, to try to prevent diabetes in non-obese diabetic (NOD) mice.