[Influence of several factors on the formation of immunologic memory]

Experiments were conducted on mice with the use of sheep erythrocytes as an antigen; the level of the secondary immune response of the spleen (in situ) cells or in adoptive transfer was in reverse relationship to the dose of erythrocytes used for primary immunization. Cyclophosphamide administered to the animals together with the antigen proved to stimulate the immune reaction of mice to the repeated erythrocyte administration; this occurred only in case of using comparatively high antigen doses for the priming. The mechanisms of the phenomenon described are discussed.