Characterization of conserved CDR3 sequence of TCR alpha- and beta-chain genes in peripheral blood T-cells from patients with diffuse large B-cell lymphoma.
T-cell immunodeficiency is a common feature in cancer patients, but clonally expanded T cells which were considered to have the specific anti-tumor cytotoxicity can be identified in most cancer patients, including those with hematological malignancies. We previously reported that there were skewed usages of T-cell receptor (TCR) Valpha and TCR Vbeta subfamily in clonally expanded T cells in the peripheral blood (PB) of patients with diffuse large B-cell lymphoma (DLBCL). In order to investigate the characteristics of the complementarity determining region 3 (CDR3) of TCR alpha- and beta-chain genes in clonally expanded T cells, the sequences of TCR-CDR3 region of clonally expanded TCR Valpha and TCR Vbeta subfamily T cells were analyzed. Conserved amino acid motifs of TCR-CDR3 region were identified in different clonally expanded T cells. RSxYNTDKLI, SxGG, GGS, and DSxY motifs were found in the TCR Valpha subfamily T-cell clones, while SxGTG, SRG, and GTxD motifs existed in the TCR Vbeta subfamily T-cell clones. Moreover, the TCR harboring conserved motif in CDR3 region of some T-cell clones had high homology in the three-dimensional spatial structures. These findings revealed the mono/oligoclonally expanded T cells were derived from the stimulation of some antigens in the PB of patients with DLBCL, and may be recognizing an identical antigenic epitope.
Institute of Hematology, Jinan University, Guangzhou, China.
Qingsong
Q
Yin
Huo
H
Tan
Shaohua
S
Chen
Lijian
L
Yang
Jingmei
J
Ye
Yangqiu
Y
Li
D000369:Aged, 80 and over; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002999:Clone Cells / Q000737:chemistry; D022801:Complementarity Determining Regions / Q000235:genetics*; D017124:Conserved Sequence; D000939:Epitopes / Q000276:immunology; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000097:blood / Q000235:genetics* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D012333:RNA, Messenger / Q000097:blood; D012334:RNA, Neoplasm / Q000097:blood; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D016176:T-Lymphocyte Subsets / Q000737:chemistry*
D022801:Complementarity Determining Regions; D000939:Epitopes; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D016693:Receptors, Antigen, T-Cell, alpha-beta