[Development of an experimental animal model of aerogenic immunization with bacterial antigens (author's transl)]

Gnotobiotic piglets once aerogenically vaccinated with a avirulent strain, B10, of live Erysipelothrix rhusiopathiae (E.r.) showed no signs of illness when exposed to 100 LD50 of the highly virulent E.r.-strain FFA two weeks later. Mice vaccinated in the same manner were not fully protected. Various serological assays provided no indication for an actual protection mechanism against the challenge infection. On the other hand preliminary evaluation of the reactivity of lymphoid cells from various organs showed remarkable differences in the response to the vaccinating antigen and to various mitogens between vaccinated and non vaccinated piglets. Developmental phases of the model system and its advantages and disadvantages are presented.