title: T cell repertoire in patients with B chronic lymphocytic leukemia. Evidence for multiple in vivo T cell clonal expansions.
abstract: To characterize circulating T cell subpopulations in B chronic lymphocytic leukemia patients, TCR V alpha and V beta gene-segment use was analyzed by PCR using a panel of V gene-segment subfamily-specific oligonucleotide primers (V alpha 1-29/V beta 1-24). Virtually all V alpha and V beta subfamily specificities were expressed in these patients (nine stage A and four stage C), and the mean values obtained for each specificity were similar to those of a group of 13 healthy donors. Nonetheless, individual analysis revealed that unique V alpha or V beta gene-segment transcripts were overrepresented in patients compared with the control group. Overrepresentation of some TCR V beta chains was also detected by cytofluorometric analysis using a panel of 18 anti-V beta-specific mAbs. To further characterize these T cell subpopulations, we sequenced five different V beta-C beta PCR products in two selected stage A patients and found highly predominant recurrent transcripts in each of the five V beta specificities (50% to 100% of the analyzed sequences with identical V(D)J regions). These results were confirmed on bulk cDNA (i.e., without cloning) and extended to other V beta specificities (up to nine clonal expansions of 24 V beta specificities in one patient) and two other patients using a PCR-based method that determines V(D)J junction size patterns. Finally, it was observed that a V beta 19+ T cell subpopulation was clonally expanded in one patient to up to 30% of circulating T cells. This V beta 19+ CD8+ T cell clone was shown to specifically recognize the autologous tumor cells in vitro, as determined in cytokine release assays. Together, these results support the view that multiple expansions of unique T cell clones may derive in vivo from B chronic lymphocytic leukemia tumor-associated Ag stimulation.
authors.affiliation: Immunology Unit, Gustave Roussy Institute, Villejuif, France.
authors.forename: F
authors.initials: F
authors.lastname: Farace
authors.forename: F
authors.initials: F
authors.lastname: Orlanducci
authors.forename: P Y
authors.initials: PY
authors.lastname: Dietrich
authors.forename: C
authors.initials: C
authors.lastname: Gaudin
authors.forename: E
authors.initials: E
authors.lastname: Angevin
authors.forename: M H
authors.initials: MH
authors.lastname: Courtier
authors.forename: C
authors.initials: C
authors.lastname: Bayle
authors.forename: T
authors.initials: T
authors.lastname: Hercend
authors.forename: F
authors.initials: F
authors.lastname: Triebel
mesh_terms: D000368:Aged; D001483:Base Sequence; D002999:Clone Cells; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014158:Transcription, Genetic
chemical_list: D016207:Cytokines; D016693:Receptors, Antigen, T-Cell, alpha-beta