Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1996-9-27
pubmed:abstractText
Immunoglobulin heavy chain variable (V) gene replacement is an unusual recombinatorial event characterized by rearrangement of a germline V gene to a preformed VDJ gene complex. This phenomenon has occasionally been implicated in the emergence of clonal subpopulations during the course of acute lymphoblastic leukemia; it has also been found in murine precursor B cell lines. V gene replacement has never been described in lymphoproliferative disorders corresponding to more differentiated stages of B cell ontogeny. The present communication provides evidence for the operation of the same mechanism in B cell chronic lymphocytic leukemia (B-CLL). Genomic DNA and total cellular RNA extracted from peripheral blood mononuclear cells of a 48-year-old female patient diagnosed as having typical B-CLL were subjected to polymerase chain reaction (PCR) amplification aiming to detect rearranged clonal heavy and light chain variable genes (VH and VL, respectively). PCR consistently gave two VH amplification products, both at the DNA and the RNA level; similar analysis for the VL region revealed the presence of a single rearranged VK gene. Direct sequence analysis of the PCR products revealed that, except for a number of silent mutations, the single rearranged VK gene was identical to the germline A1-A17 VK gene. The two rearranged VH gene segments belong to the VHl and VHIII gene families and are closely homologous, respectively, to the germline gene segments V1-18 and V3-30, which have been shown to be used by autoantibodies. Both rearranged VH genes showed identical in-frame D-N-JH junctions and JH gene usage (JH5b), whereas the VH-N-D junctions were different. The above findings indicate that, during the course of the disease of our patient, VH gene replacement took place giving rise to two different clonally related subpopulations. This raises the intriguing possibility that the recombinase machinery, which governs Ig recombinatorial processes, might be operative even at more advanced stages in B cell ontogeny.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0887-6924
pubmed:author
pubmed:issnType
Print
pubmed:volume
10
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1551-6
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Evidence for immunoglobulin heavy chain variable region gene replacement in a patient with B cell chronic lymphocytic leukemia.
pubmed:affiliation
First Department of Medicine, Laikon General Hospital, University of Athens School of Medicine, Greece.
pubmed:publicationType
Journal Article, Case Reports, Research Support, Non-U.S. Gov't