Abstract
B-cell chronic lymphocytic leukemia (CLL) patients display leukemic clones bearing either germline or somatically mutated immunoglobulin heavy variable (IGHV) genes. Most information on CLL immunoglobulins (Igs), such as the definition of stereotyped B-cell receptors (BCRs), was derived from germline unmutated Igs. In particular, detailed studies on the distribution and nature of mutations in paired heavy- and light-chain domains of CLL clones bearing mutated Igs are lacking. To address the somatic hypermutation dynamics of CLL Igs, we analyzed the mutation pattern of paired IGHV-diversity-joining (IGHV-D-J) and immunoglobulin kappa/lambda variable-joining (IGK/LV-J) rearrangements of 193 leukemic clones that displayed ≥2% mutations in at least one of the two immunoglobulin variable (IGV) genes (IGHV and/or IGK/LV). The relationship between the mutation frequency in IGHV and IGK/LV complementarity determining regions (CDRs) and framework regions (FRs) was evaluated by correlation analysis. Replacement (R) mutation frequency within IGK/LV chain CDRs correlated significantly with mutation frequency of paired IGHV CDRs in λ but not κ isotype CLL clones. CDRs of IGKV-J rearrangements displayed a lower percentage of R mutations than IGHVs. The frequency/pattern of mutations in kappa CLL Igs differed also from that in κ-expressing normal B cells described in the literature. Instead, the mutation frequency within the FRs of IGHV and either IGKV or IGLV was correlated. Notably, the amount of diversity introduced by replaced amino acids was comparable between IGHVs and IGKVs. The data indicate a different mutation pattern between κ and λ isotype CLL clones and suggest an antigenic selection that, in κ samples, operates against CDR variation.
| Original language | English |
|---|---|
| Pages (from-to) | 1188-1195 |
| Number of pages | 8 |
| Journal | Molecular medicine (Cambridge, Mass.) |
| Volume | 17 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - Nov 2011 |
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ASJC Scopus subject areas
- Genetics
- Molecular Biology
- Molecular Medicine
- Genetics(clinical)
Cite this
Mutation pattern of paired immunoglobulin heavy and light variable domains in chronic lymphocytic leukemia B cells. / Ghiotto, Fabio; Marcatili, Paolo; Tenca, Claudya; Calevo, Maria Grazia; Yan, Xiao Jie; Albesiano, Emilia; Bagnara, Davide; Colombo, Monica; Cutrona, Giovanna; Chu, Charles C.; Morabito, Fortunato; Bruno, Silvia; Ferrarini, Manlio; Tramontano, Anna; Fais, Franco; Chiorazzi, Nicholas.
In: Molecular medicine (Cambridge, Mass.), Vol. 17, No. 11, 11.2011, p. 1188-1195.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Mutation pattern of paired immunoglobulin heavy and light variable domains in chronic lymphocytic leukemia B cells
AU - Ghiotto, Fabio
AU - Marcatili, Paolo
AU - Tenca, Claudya
AU - Calevo, Maria Grazia
AU - Yan, Xiao Jie
AU - Albesiano, Emilia
AU - Bagnara, Davide
AU - Colombo, Monica
AU - Cutrona, Giovanna
AU - Chu, Charles C.
AU - Morabito, Fortunato
AU - Bruno, Silvia
AU - Ferrarini, Manlio
AU - Tramontano, Anna
AU - Fais, Franco
AU - Chiorazzi, Nicholas
PY - 2011/11
Y1 - 2011/11
N2 - B-cell chronic lymphocytic leukemia (CLL) patients display leukemic clones bearing either germline or somatically mutated immunoglobulin heavy variable (IGHV) genes. Most information on CLL immunoglobulins (Igs), such as the definition of stereotyped B-cell receptors (BCRs), was derived from germline unmutated Igs. In particular, detailed studies on the distribution and nature of mutations in paired heavy- and light-chain domains of CLL clones bearing mutated Igs are lacking. To address the somatic hypermutation dynamics of CLL Igs, we analyzed the mutation pattern of paired IGHV-diversity-joining (IGHV-D-J) and immunoglobulin kappa/lambda variable-joining (IGK/LV-J) rearrangements of 193 leukemic clones that displayed ≥2% mutations in at least one of the two immunoglobulin variable (IGV) genes (IGHV and/or IGK/LV). The relationship between the mutation frequency in IGHV and IGK/LV complementarity determining regions (CDRs) and framework regions (FRs) was evaluated by correlation analysis. Replacement (R) mutation frequency within IGK/LV chain CDRs correlated significantly with mutation frequency of paired IGHV CDRs in λ but not κ isotype CLL clones. CDRs of IGKV-J rearrangements displayed a lower percentage of R mutations than IGHVs. The frequency/pattern of mutations in kappa CLL Igs differed also from that in κ-expressing normal B cells described in the literature. Instead, the mutation frequency within the FRs of IGHV and either IGKV or IGLV was correlated. Notably, the amount of diversity introduced by replaced amino acids was comparable between IGHVs and IGKVs. The data indicate a different mutation pattern between κ and λ isotype CLL clones and suggest an antigenic selection that, in κ samples, operates against CDR variation.
AB - B-cell chronic lymphocytic leukemia (CLL) patients display leukemic clones bearing either germline or somatically mutated immunoglobulin heavy variable (IGHV) genes. Most information on CLL immunoglobulins (Igs), such as the definition of stereotyped B-cell receptors (BCRs), was derived from germline unmutated Igs. In particular, detailed studies on the distribution and nature of mutations in paired heavy- and light-chain domains of CLL clones bearing mutated Igs are lacking. To address the somatic hypermutation dynamics of CLL Igs, we analyzed the mutation pattern of paired IGHV-diversity-joining (IGHV-D-J) and immunoglobulin kappa/lambda variable-joining (IGK/LV-J) rearrangements of 193 leukemic clones that displayed ≥2% mutations in at least one of the two immunoglobulin variable (IGV) genes (IGHV and/or IGK/LV). The relationship between the mutation frequency in IGHV and IGK/LV complementarity determining regions (CDRs) and framework regions (FRs) was evaluated by correlation analysis. Replacement (R) mutation frequency within IGK/LV chain CDRs correlated significantly with mutation frequency of paired IGHV CDRs in λ but not κ isotype CLL clones. CDRs of IGKV-J rearrangements displayed a lower percentage of R mutations than IGHVs. The frequency/pattern of mutations in kappa CLL Igs differed also from that in κ-expressing normal B cells described in the literature. Instead, the mutation frequency within the FRs of IGHV and either IGKV or IGLV was correlated. Notably, the amount of diversity introduced by replaced amino acids was comparable between IGHVs and IGKVs. The data indicate a different mutation pattern between κ and λ isotype CLL clones and suggest an antigenic selection that, in κ samples, operates against CDR variation.
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UR - http://www.scopus.com/inward/citedby.url?scp=82855172234&partnerID=8YFLogxK
U2 - 10.2119/molmed.2011.00104
DO - 10.2119/molmed.2011.00104
M3 - Article
C2 - 21785810
AN - SCOPUS:82855172234
VL - 17
SP - 1188
EP - 1195
JO - Molecular Medicine
JF - Molecular Medicine
SN - 1076-1551
IS - 11
ER -