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Cloning of Antibody-Producing Cells in Vivo


 A method is described for analyzing serum by isoelectric focusing in thin layer polyacrylamide gels and detecting specific antibody bands by 131I-hapten binding and autoradiography. The isoelectric spectrum of a biosynthetically homogeneous immunoglobulin produced by a single clone of plasma cells is a characteristic pattern of a few bands; such patterns provide phenotypic markers for antibody-forming cell clones. Anti-DNP-forming cell clones were distributed from primed mice by spleen cell transfer at limiting dilution into irradiated syngeneic mice. Preliminary results did not indicate a limit to the number of different anti-DNP antibody molecules. Selected single clones could be propagated by serial spleen cell transfer. The history and properties of one clone (E9) producing IgG anti-DNP are described. Transfer was mediated by memory-precursor cells; antibody production was strictly dependent on antigen (DNP-BGG) at each generation.