title: CD7- T cells represent a subset of normal human blood lymphocytes.
abstract: In the peripheral blood of normal adults we identified a subpopulation of mature human T cells that lacks expression of CD7. These CD3+CD7- T cells represent 9% +/- 3.4 SD of PBMC as estimated by analyses of 38 different normal donors. The majority of CD7- T cells express TCR alpha/beta, and are of CD4 helper and CD45RO+CD45RA- "memory" phenotype as determined by three-color fluorescence analysis. We established seven CD4+CD7- T cell clones in vitro from purified CD7- blood T cells and compared these cells to CD4+CD7+ clones. Nonexpression and expression, respectively, of CD7 was a stable feature of all clones during long term culture for more than 6 mo. No CD7 mRNA could be detected by dot blot and Northern blot analysis of purified CD7- T cells and of expanded T cell clones implicating a transcriptional regulation of CD7 Ag expression. Ionomycin/TPA and PHA stimulation were not capable to induce CD7 expression in CD7- cells but up-regulated CD7 expression in CD7+ cells. Whereas CD7- cells of cutaneous T cell lymphoma exhibit a cerebriform nucleus (Sézary cells), no evidence was obtained for cerebriform nuclear morphology in normal CD7- T cells from peripheral blood. We suggest that these CD7- T cells represent a physiologic subset of mature T cells and may be the circulating counterpart of those lymphocytes that are found to be enriched in normal skin and in a variety of benign and malignant skin diseases.
authors.affiliation: Department of Dermatology, University of Bonn, FRG.
authors.forename: U
authors.initials: U
authors.lastname: Reinhold
authors.forename: H
authors.initials: H
authors.lastname: Abken
authors.forename: S
authors.initials: S
authors.lastname: Kukel
authors.forename: M
authors.initials: M
authors.lastname: Moll
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: I
authors.initials: I
authors.lastname: Oltermann
authors.forename: H W
authors.initials: HW
authors.lastname: Kreysel
mesh_terms: D015703:Antigens, CD / Q000032:analysis* / Q000235:genetics; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis* / Q000235:genetics; D001483:Base Sequence; D002999:Clone Cells; D016207:Cytokines / Q000378:metabolism; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D015703:Antigens, CD; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte; D016207:Cytokines; D012333:RNA, Messenger