THE SECONDARY B-CELL LINEAGE FOR PHOSPHORYLCHOLINE IS CONSERVED IN CBA CAHN-XID/J MICE/

In order to determine the mechanism of generation of immunological mem ory, we used the splenic focus assay to analyze primary and in vitro g enerated secondary phosphorylcholine (PC)specific B cell precursors in CBA/CaHN-xid/J mice (CBA/N) expressing an X-linked immune defect (xid ). A quantitative analysis of the kinetics of the appearance of these precursors over the time of the culture period was performed. The prec ursors were analyzed for TEPC15 idiotype expression and epitope specif icity. We found that there was a significantly reduced total frequency of PC-specific precursors in CBA/N female and (CBA/CaHN-xid/J female X BALB/cRos male)F-1 (NBF1) male mice (rid phenotype), relative to BAL B/c and NBF1 female mice (normal phenotype). Memory precursors represe nting a distinct lineage of B cells, however, were present at normal l evels in CBA/N female and NBF1 male mice. These results help explain t he reported characteristics of the serum antibody responses induced in these mice and also better our understanding of the mechanism of B ce ll memory generation. (C) 1994 Academic Press, Inc.