Cells Involved in the Immune Response. XX. The “All or None” Nature of the Primary Immune Response (19S Antibody) by Individual Antibody-Forming Cells in the Rabbit

摘要

The cells that synthesize 19S antibodies in the rabbit following primary intravenous immunization have been shown to be localized in the spleen, using the hemolysis in agar (plaque) technique (1). The temporal relationships are such that the 19S antibody-forming cells (AFC) cannot be detected in appreciable numbers before 4 to 5 days after immunization, but they then increase in number markedly within 24 hr. However, what has not been ascertained is whether this explosive increase in the AFC population is due to a) rapid division of these cells, each progeny being immediately capable of synthesizing large quantities of antibody, b) a synchronous phase of rapid antibody formation by non-dividing cells, or c) increasing amounts of antibody being synthesized by the AFC, thus permitting the detection of increasing numbers of non-dividing AFC. The results presented below strongly support but do not discriminate between the first two hypotheses.