Murine IgG1 and IgE memory B cells.

Anti-dinitrophenyl IgG1 and IgE antibody production were examined in vitro. Splenic B cells from mice immunized in vivo at various intervals with dinitrophenylated proteins were cultured in vitro with splenic T cells and splenic antigen-presenting cells from mice immunized previously (2 weeks) with keyhole limpet hemocyanin. Anti-dinitrophenyl IgG1 and IgE antibodies were determined in the supernatants by ELISA. Without T cells and antigen-presenting cells or without antigen, no anti-dinitrophenyl antibodies were detected. When the B cells were separated by panning with anti-murine IgG1 antibody, only the cells adhering to anti-IgG1 produced anti-dinitrophenyl IgG1 antibodies. Anti-dinitrophenyl IgE production was observed from cells adhering and from cells not adhering to the anti-IgG1-coated plates, as expected. However, anti-dinitrophenyl IgE was also produced from cells which adhered to the anti-IgG1-coated plates, but did not have surface IgE antibodies. Therefore, cells without surface IgE adhering to anti-IgG1 were capable of producing anti-dinitrophenyl IgE antibodies.