[Dynamics of DNA synthesis and blast cell reproduction during formation of the primary immune response and...

A study was made of the dynamics of the DNA synthesis and of the reproduction of the blast cells in the spleen by the methods of autoradiography and radiometry under conditions of a single intervenous immunization of CBA mice with high and low doses of sheep erythrocytes. In the formation of immunological memory stimulated by a subimmunizing dose of the antigen (1-10(5) erythrocytes) cell changes were observed almost exclusively in the periarterial zone; as to the primary response caused by a high dose of the antigen (1-10(9) erythrocytes), it was accompanied by the changes in the cell composition in all the zones of the spleen under study (periarterial, mantle, embryonic centres, red pulp). The maximal accretion of the blast count was observed in the both cases on the second day after the antigen administration. Dynamics of the specific intensity of the 3H-thymidine incorporation into the tissues of the spleen showed the greatest correspondence with the dynamics of the cell changes in the periarterial zone of the spleen.