DNA Synthesis by Antibody-forming Cells during the Primary Immune Response

Abstract

THE mechanism of the rapid increase in specific antibody-producing cells during the primary immune response may involve cell division, cell “recruitment”, or a combination of both. The use of mitotic blocking agents has indicated that very rapid cell division, stimulated by antigen, alone accounts for the rapid increase in haemolytic plaque-forming cells during the primary response by the mouse to sheep erythrocytes¹. Several autoradiographic studies were also interpreted to indicate an antigen-stimulated increase in the rate of division by plaque-forming cells during the primary response^2,3. One group has, however, interpreted its own and other autoradiographic data to indicate that antigen does not stimulate more rapid division by plaque-forming cells^4,5. Two of these studies^2,5 involved examination of plaque-forming cells only, sampled on one day. The other two studies^3,4 were severely limited in sensitivity by the technique for examining DNA synthesis—continuous exposure to ³H-thymidine from the time of antigen administration to the time of death.