The relationship between surface immunoglobulin isotype and the immune function of murine B lymphocytes. V. High affinity secondary antibody responses are transferred by both IgD-positive and IgD-negative memory B cells

We examined the adoptive secondary anti-DNP responses restored by surface IgD⁺ and IgD^- memory B cells. Several parameters that might affect the affinity and magnitude of the adoptive responses were studied: 1) time after priming of cell donors, 2) source of anti-IgD antibodies used for immunofluorescent cell staining, 3) adjuvant used for priming, 4) carrier protein used for priming, 5) amount of antigen used for the challenge of adoptive hosts, and 6) the strain of mice used as donors and recipients. In contrast to previous reports, the present results demonstrate that the selection of cells with high affinity antigen receptors can occur to the same extent in both the δ⁺ and δ^- memory cell pools. This suggests that the loss of surface IgD is not a necessary intermediate stage in the maturation of memory B cells.