The B cell antigen receptor in atypical chronic lymphocytic leukemia with t(14;19)(q32;q13) demonstrates remarkable stereotypy.
The t(14;19)(q32;q13) is a recurrent chromosomal translocation reported in a variety of B-cell leukemias and lymphomas, including chronic lymphocytic leukemia (CLL). CLL cases associated with t(14;19) often have atypical morphologic and immunophenotypic features and unmutated immunoglobulin heavy chain (IGH) variable region (V) genes, associated with an aggressive clinical course. We analyzed IGHV somatic mutation status and gene use in 11 patients with t(14;19)-positive CLL. All cases were unmutated, and the IGHV genes in 10 cases showed minimal deviation from germline sequences. In 7 of 11 patients, we found homologous heavy chain rearrangements using IGHV4-39; light chain analysis revealed identical IGKV1-39 use. Corresponding V-(D)-J sequences demonstrated remarkable stereotypy of the immunoglobulin heavy and kappa light chain complementarity determining region 3 (H/K CDR3) genes. These findings raise the possibility that specific antigen drive is involved in the clonal development and/or selection of t(14;19)(q32;q13)-positive CLL cells. Our findings support the hypothesis that stimulatory signals through specific antigen receptors may promote the expansion of either CLL precursor cells or CLL clones that harbor distinct chromosomal abnormalities.
Schweighofer
Carmen D
CD
Department of Hematopathology, The University of Texas M D Anderson Cancer Center, Houston, TX 77030, USA.
Huh
Yang O
YO
Luthra
Rajyalakshmi
R
Sargent
Rachel L
RL
Ketterling
Rhett P
RP
Knudson
Ryan A
RA
Barron
Lynn L
LL
Medeiros
L Jeffrey
LJ
Keating
Michael J
MJ
Abruzzo
Lynne V
LV
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D022801:Complementarity Determining Regions / Q000235:genetics*; D005260:Female; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain / Q000235:genetics; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D016130:Immunophenotyping; D007621:Karyotyping; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011947:Receptors, Antigen, B-Cell / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics*
D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region; D011947:Receptors, Antigen, B-Cell