Formulations/buffers influence the conformation of proteins in solution and can consequently affect processes such as antigen uptake and processing, thus altering the availability of T cell epitopes on the surface of antigen presenting cells. Formulations can therefore be tested using the EpiScreen™ assay to determine the effects on T cell stimulation. The EpiScreen™ assay has been successfully used for analysis of different formulations of recombinant human proteins (for example human interferon ?) resulting in the identification of new formulations with reduced potential for immunogenicity in patients. Antitope has tested a variety of new formulations including aqueous formulations, microparticles, gels, complexes, liposomes and other microvesicles to determine the effects on the potential for immunogenicity.