Somatic mutation and clonal expansion of B cells in an antigen‐driven immune response

• Published in: The EMBO journal 1985-02, Vol.4 (2), p.345-350
• Main Authors: Sablitzky, F., Wildner, G., Rajewsky, K.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Analysis of the immune response. Humoral and cellular immunity; Animals; Antibodies, Anti-Idiotypic - immunology; Antibodies, Monoclonal - genetics; Antibodies, Monoclonal - immunology; Antibody-Producing Cells - immunology; Antibody-Producing Cells - physiology; B-Lymphocytes - cytology; B-Lymphocytes - immunology; B-Lymphocytes - physiology; Base Sequence; Biological and medical sciences; Clone Cells - immunology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Hybridomas; Immunobiology; Immunoglobulin Heavy Chains - genetics; Immunoglobulin Idiotypes - immunology; Immunoglobulin Variable Region - genetics; Mice; Mutation; Organs and cells involved in the immune response
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1985.tb03635.x

The variable (V) regions of three closely related monoclonal antibodies produced by hybridomas which had been isolated from a single mouse were sequenced at the level of the mRNA. The sequences and the restriction analysis of the immunoglobulin loci carried by the hybridoma cells indicate that the antibodies are derived from cells belonging to a single B cell clone. The sequence data imply a high frequency and stepwise occurrence of somatic point mutations in the expressed V region genes and substantial clonal expansion of B cells in the mouse. The mutations appear to be randomly introduced into heavy and light chain V region genes. Mutations are also seen in the complementarity determining regions which may thus have been involved in the selection of the cells producing the three antibodies.