title: Reciprocal expression of CD70 and of its receptor, CD27, in human long term-activated T and natural killer (NK) cells: inverse regulation by cytokines and role in induction of cytotoxicity.
abstract: By transfection of COS cells with an expression vector containing CD70 cDNA we demonstrate that two previously described MoAbs (ED6 and LD6) recognize CD70. By means of these MoAbs, we show that the surface expression of CD70 inversely correlates with the expression of its receptor, CD27, on activated T and NK cell populations and clones, although a subpopulation of cells expressing low density of both molecules exists. In addition, culture in the presence of IL-4 significantly enhances CD27 and reduces CD70 surface expression in phytohaemagglutinin (PHA)-activated peripheral blood lymphocytes (PBL), while tumour necrosis factor-alpha (TNF-alpha) displays opposite effects, indicating that receptor and ligand are reciprocally regulated by these cytokines. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of CD27 and CD70 mRNA suggests a transcriptional control of CD27 antigen expression in T cell clones. In addition, we show by the use of a re-directed killing assay that in cytotoxic T cell receptor (TCR) alpha/beta+ T cell clones, CD27 molecule may be involved in the regulation of cytolytic functions and may act synergistically with CD2. Finally, CD70 also acts as a signal-transducing molecule in some activated CD70+ TCR gamma/delta+ T or NK cell clones. In conclusion, our data indicate that CD27 and CD70 molecules are differentially expressed and regulated on long term-activated T and NK cells and are involved in the control of cellular functions.
authors.affiliation: Istituto Nazionale per la Ricerca sul Cancro, Centro di Biotecnologie Avanzate, Genoa, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Orengo
authors.forename: C
authors.initials: C
authors.lastname: Cantoni
authors.forename: F
authors.initials: F
authors.lastname: Neglia
authors.forename: R
authors.initials: R
authors.lastname: Biassoni
authors.forename: S
authors.initials: S
authors.lastname: Ferrini
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000937:Antigen-Antibody Reactions; D015703:Antigens, CD; D053282:CD27 Ligand; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism*; D008213:Lymphocyte Activation / Q000187:drug effects; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000276:immunology / Q000494:pharmacology*; D011971:Receptors, Immunologic / Q000096:biosynthesis / Q000187:drug effects; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000096:biosynthesis* / Q000276:immunology / Q000494:pharmacology*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D053282:CD27 Ligand; C505771:CD70 protein, human; D016207:Cytokines; D008565:Membrane Proteins; D011971:Receptors, Immunologic; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7