Molecular cloning of a human immunoglobulin heavy chain variable (V H) region with anti-myelin-associated glycoprotein activity

A cDNA clone that encodes the heavy chain variable region (V H) of an IgM M-protein with anti-myelin-associated glycoprotein (MAG) activity secreted by chronic lymphocytic leukemia cells (B-C11) from a patient with peripheral neuropathy was cloned and sequenced. The J H region was identical to the germline J H 4 sequence except for deletion of a thymidine residue at the site of D-J H recombination, and the D region showed greatest homology to DM2. Sequence analysis of the V H region revealed greatest homology to V H 26, a member of the V H3 gene family, but homology was only 83.7% over 326 bases, suggesting that it was derived from as yet an unidentified member of the V H 3 gene family.