Analysis of antibody populations to oligo-D-alanine. VIII. Sequential studies on properties of antibody subpopulations: rate constant, affinity, and isoelectric focusing spectrum.

Allotypically marked antisera to the hapten oligo-D-alanine were studied over periods up to 10 months in individual mice and in serial transfers of both nonimmune and memory cells to irradiated recipients. Parameters observed were divalent association rate constants, affinity and autoradiography of isoelectric focusing (IEF) spectra. The two allotypic subpopulations of heterozygous mice are shown to be independent with respect to affinity. Association rate constant, affinity, and IEF spectra of the antibody populations remain largely stable in most mice over prolonged periods. There is an occasional isolated dramatic change in a single property of one allotypic subpopulation; this may be in the direction of either lower or higher rate constant or affinity. While different recipients of naive spleen cells from a single donor, when immunized, differ one from the other in the measured antibody properties, the characteristics now established in each recipient persist in a lineage of transferred memory cells up to 4 generations, with infrequent changes in isolated properties of only one allotypic subpopulation. The limited changes observed would be in agreement with a model of moderate somatic variability superimposed on a small spectrum of germ line genes.