Open AccessAssembly and secretion of pentameric IgM in a fusion between a nonsecreting B cell lymphoma and an IgG-secreting plasmacytoma.
Author(s) -
William C. Raschke,
Elizabeth L. Mather,
Marian Elliott Koshland
Publication year - 1979
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.76.7.3469
Subject(s) - j chain , biology , b cell , microbiology and biotechnology , cell culture , cell fusion , immunoglobulin m , secretion , raji cell , antibody , immunoglobulin light chain , cellular differentiation , immunoglobulin g , biochemistry , immunology , genetics , gene
A new immunoglobulin product has been obtained by hybridization of mouse cell lines arrested at different stages in B lymphocyte development. One line was shown to have the characteristics of an undifferentiated B cell that synthesizes monomeric IgM as a membrane receptor but does not express J chain. The second line was represent of a fully differentiated plasma cell synthesizing large amounts of IgG and J chain, but no IgM. Fusion of the two cell types yielded independent hybrid clones that secreted pentameric IgM, normally the first product of antigen-driven B cell differentiation. Analyses of the hybrid cells indicated that the IgM was expressed as a result of complementation between the synthetic capacities of the parental lines. The hybrid cells synthesized both monomeric IgM and J chain and assembled these components into a pentameric molecule with the expected stoichiometry of one J chain per five monomeric units. These findings provided further evidence that the induction of B cell differentiation includes a signal for de novo synthesis of the J chain. Moreover, the complementation achieved by this hybridization provides a system for identifying other intracellular events in B cell differentiation to IgM secretion.