Similarities and differences between the light and heavy chain Ig variable region gene repertoires in chronic lymphocytic leukemia.
Analyses of Ig V(H)DJ(H) rearrangements expressed by B-CLL cells have provided insights into the antigen receptor repertoire of B-CLL cells and the maturation stages of B-lymphocytes that give rise to this disease. However, less information is available about the L chain V gene segments utilized by B-CLL cells and to what extent their characteristics resemble those of the H chain. We analyzed the V(L) and J(L) gene segments of 206 B-CLL patients, paying particular attention to frequency of use and association, mutation status, and LCDR3 characteristics. Approximately 40% of B-CLL cases express V(L) genes that differ significantly from their germline counterparts. Certain genes were virtually always mutated and others virtually never. In addition, preferential pairing of specific V(L) and J(L) segments was found. These findings are reminiscent of the expressed VH repertoire in B-CLL. However unlike the V(H) repertoire, V(L) gene use was not significantly different than that of normal B-lymphocytes. In addition, Vkappa genes that lie more upstream on the germline locus were less frequently mutated than those at the 3' end of the locus; this was not the case for Vlambda genes and is not for V(H) genes. These similarities and differences between the IgH and IgL V gene repertoires expressed in B-CLL suggest some novel features while also reinforcing concepts derived from studies of the IgH repertoire.
Ghiotto
Fabio
F
Department of Medicine, North Shore University Hospital, Manhasset, NY, USA. fghiotto@unige.it
Fais
Franco
F
Albesiano
Emilia
E
Sison
Cristina
C
Valetto
Angelo
A
Gaidano
Gianluca
G
Reinhardt
Janine
J
Kolitz
Jonathan E
JE
Rai
Kanti
K
Allen
Steven L
SL
Ferrarini
Manlio
M
Chiorazzi
Nicholas
N
D015703:Antigens, CD / Q000097:blood / Q000276:immunology; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D005787:Gene Frequency; D015321:Gene Rearrangement / Q000276:immunology; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000235:genetics*; D007075:Immunoglobulin M / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics / Q000276:immunology*; D005810:Multigene Family; D009154:Mutation; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D012016:Reference Values
D015703:Antigens, CD; D018076:DNA, Complementary; D007143:Immunoglobulin Heavy Chains; D007133:Immunoglobulin Joining Region; D007147:Immunoglobulin Light Chains; D007075:Immunoglobulin M; D007135:Immunoglobulin Variable Region; D012334:RNA, Neoplasm