title: Shortened telomere length is demonstrated in T-cell subsets together with a pronounced increased telomerase activity in CD4 positive T cells from blood of patients with mycosis fungoides and parapsoriasis.
abstract: We have recently demonstrated that telomerase activity is increased and telomere length shortened in lymphocytes from peripheral blood of patients with cutaneous T-cell lymphoma. In order to determine which cell type has increased telomerase activity and shortened telomere length, CD4+, CD8+, CLA+ CD3+ and CLA- CD3+ T cells were isolated from peripheral blood of 25 patients, including 15 patients with mycosis fungoides and 10 patients with parapsoriasis. Eleven healthy individuals were used as controls; CD19+ B cells were separated from each individual as an internal control. The results showed that the increased telomerase activity was significantly predominating in the CD4+ T-cell subset. Significantly shortened telomere length was found in CD4+ and CD8+ T-cell subsets from the patients compared with the same cell subsets obtained from healthy individuals. However, no difference was observed between the subsets; CD19+ B cells collected from patients and healthy control individuals had similar telomerase activity and telomere length which was significantly different from the values found in T cells. The telomere length was significantly shorter in CLA+ CD3+ subset than in CLA- CD3+ subset. Interestingly, increased telomerase activity and shortened telomere length was also detected in CD4+ T cells from patients with parapsoriasis indicating that alteration of telomerase activity and telomere length in CD4+ T cells is an early event in the pathogenesis of cutaneous T-cell lymphoma. Thus, the results indicate that a significant high level of telomerase activity and shortened telomere length frequently occur in T cells of patients with CTCL and may reflect tumorigenesis.
authors.affiliation: Department of Dermatology, Marselisborg Hospital, University of Aarhus, 8000 Aarhus C, Denmark. wuk@mskcc.org
authors.forename: K D
authors.initials: KD
authors.lastname: Wu
authors.forename: E R
authors.initials: ER
authors.lastname: Hansen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D001402:B-Lymphocytes / Q000502:physiology; D015139:Blotting, Southern; D017252:CD3 Complex / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000201:enzymology*; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis; D008875:Middle Aged; D009182:Mycosis Fungoides / Q000097:blood* / Q000201:enzymology / Q000235:genetics / Q000276:immunology; D010267:Parapsoriasis / Q000097:blood* / Q000201:enzymology / Q000235:genetics; D012016:Reference Values; D015183:Restriction Mapping; D016176:T-Lymphocyte Subsets / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology / Q000502:physiology; D019098:Telomerase / Q000378:metabolism*; D016615:Telomere / Q000235:genetics*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D017252:CD3 Complex; C063419:CTAGE1 protein, human; D008562:Membrane Glycoproteins; D019098:Telomerase