The relationship between surface immunoglobulin isotype and immune function of murine B lymphocytes. I. Surface immunoglobulin isotypes on primed B cells in the spleen.

Abstract

The ability of Ig[immunoglobulin]M-, IgD- and IgG-bearing cells from the spleens of (BALB/c .times. C57BL/Ka)F1 mice primed to dinitrophenyl-bovine serum albumin (DNP-BSA) to restore the adoptive secondary anti-BSA and anti-DNP antibody responses was investigated. A rabbit anti-mouse IgD antiserum was prepared and the specficity documented by radioimmunoprecipitation and cell surface staining. Purified populations of IgM-, IgD- and IgG-bearing cells were prepared by immunofluorescent staining with isotype-specific reagents, and sorting on the fluorescence activated cell sorter. Bright or dull cells were transferred to irradiated syngeneic recipients which were challenged with DNP-BSA in saline. Unfractionated spleen cells restored an adoptive secondary serum antibody response which was all IgG (2-mercaptoethanol resistant). Purified IgM- or IgD-bearing cells restored the secondary IgM and IgG antibody response. IgG-bearing cells restored only the IgG response. IgG-bearing cells appear to suppress the adoptive secondary IgM response, since depletion of IgG-bearing cells from transferred spleen cells results in a marked increase in the adoptive IgM response.