title: Immunoglobulin gene segment usage, location and immunogenicity in mutated and unmutated chronic lymphocytic leukaemia.
abstract: The mutational status of the variable region of the immunoglobulin heavy chain gene (IgV(H)) is an important prognostic marker in B-cell chronic lymphocytic leukaemia (B-CLL), with mutated patients having improved outcome. To examine the impact of mutational status on V(H), D(H), and J(H) gene segment location and immunogenicity, we analysed 375 IgH sequences from 356 patients with B-CLL. Although V(H) and D(H) gene usage was different in mutated compared to unmutated patients, there was no impact of gene location on frequency of use or clinical outcome. Surprisingly, somatic mutations did not increase the immunogenicity of the Ig, as assessed by predicted binding affinity of Ig-derived peptides to major histocompatibility Class I and Class II molecules. Even excluding patients using V(H)1-69, cases using the V(H)1 gene family had a poor outcome. Both mutated and unmutated CLL patients demonstrated evidence of antigen selection. The worst outcome was seen in the subset of 14 unmutated patients with similar HCDR3 amino acid sequence using V(H)1-69, D(H)3-3 and J(H)6, suggesting an antigen-driven process modulating the clinical course.
authors.affiliation: Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: Katja
authors.initials: K
authors.lastname: Mauerer
authors.forename: David
authors.initials: D
authors.lastname: Zahrieh
authors.forename: Gullu
authors.initials: G
authors.lastname: Gorgun
authors.forename: Aihong
authors.initials: A
authors.lastname: Li
authors.forename: Jianbiao
authors.initials: J
authors.lastname: Zhou
authors.forename: Sascha
authors.initials: S
authors.lastname: Ansén
authors.forename: Laura Z
authors.initials: LZ
authors.lastname: Rassenti
authors.forename: John G
authors.initials: JG
authors.lastname: Gribben
mesh_terms: D000595:Amino Acid Sequence; D004252:DNA Mutational Analysis; D000939:Epitopes; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D005803:Genes, Immunoglobulin; D015803:HLA-DR3 Antigen / Q000235:genetics / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics* / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics* / Q000276:immunology; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D011379:Prognosis; D016415:Sequence Alignment
chemical_list: D000939:Epitopes; D015803:HLA-DR3 Antigen; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region