Affiliation:
1. From the Division of Hematology/Oncology, Department of Medicine, University of California at San Diego, La Jolla, California 92093-0663
Abstract
We determined the immunoglobulin (Ig) VH subgroup expressed by the leukemia cells of 108 patients with B cell chronic lymphocytic leukemia (CLL). Surprisingly, we found that six samples (5%) each expressed Ig of more than one VH subgroup. Southern blot analysis demonstrated that these samples each had rearrangements involving both Ig heavy chain alleles. Nucleic acid sequence analyses of the Ig cDNA revealed each to express two functional Ig VH genes: VH3-33 and VH4-39; VH3-7 and VH4-39; VH3-23 and VH4-61; VH2-70 and VH3-30.3; or VH3-30 and VH4-b (DP67). One sample expressed three Ig VH genes: VH2-70, VH3-7, and VH4-59. Despite having more than one Ig heavy chain transcript, each sample was found to express only one functional Ig light chain. From the primary sequence, we deduced that the Ig of some of these CLL samples should react with Lc1, a monoclonal antibody (mAb) reactive with a supratypic cross-reactive idiotype present on Ig encoded by a subgroup of Ig VH4 genes (namely, VH4-39, VH4-b [DP-67], VH4-59, or VH4-61), and B6, an mAb that reacts with Ig encoded by certain Ig VH3 genes (namely, VH3-23, VH3-30, or VH3-30.3), and/or modified staphylococcal protein A (SpA), a 45-kilodalton bacterial “superantigen” that reacts with most Ig of the VH3 subgroup. Flow cytometric analyses revealed that such samples did in fact react with Lc1 and B6 and/or SpA, but not with control mAbs of irrelevant specificity. This study demonstrates that a subset of CLL patients have leukemic B cells that express more than one functional Ig heavy chain.
Publisher
Rockefeller University Press
Subject
Immunology,Immunology and Allergy
Cited by
89 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献