A novel cell penetrating aspartic protease inhibitor blocks processing and presentation of tetanus toxoid more efficiently than pepstatin A - Zaidi, Nousheen; Burster, Timo; Sommandas, Vinod; Herrmann, Timo; Boehm, Bernhard O.; Driessen, Christoph; Voelter, Wolfgang; Kalbacher, Hubert (Biochemical & Biophysical Research Communications, 2007)