title: CD8-β ADP-ribosylation affects CD8(+) T-cell function.
abstract: The CD8αβ coreceptor is crucial for effective peptide: MHC-I recognition by the TCR of CD8(+) T cells. Adenosine diphosphate ribosyl transferase 2.2 (ART2.2) utilizes extracellular NAD(+) to transfer ADP-ribose to arginine residues of extracellular domains of surface proteins. Here, we show that in the presence of extracellular NAD(+) , ART2.2 caused ADP-ribosylation of CD8-β on murine CD8(+) T cells in vitro and in vivo. Treatment with NAD(+) prevented binding of anti-CD8-β mAb YTS156.7.7 but not of mAb H35-17.2, indicating that NAD(+) caused modification of certain epitopes and not a general loss of CD8-β. Loss of antibody binding was strictly dependent on ART2.2, because it was not observed on ART2-deficient T cells or in the presence of inhibitory anti-ART2.2 single-domain antibodies. ADP-ribosylation of CD8-β occurred during cell isolation, particularly when cells were isolated from CD38-deficient mice. Incubation of ART2-expressing, but not of ART2-deficient, OVA-specific CD8(+) T cells with NAD(+) interfered with binding of OVA257-264 :MHC-I tetramers. In line with this result, treatment of WT mice with NAD(+) resulted in reduced CD8(+) T-cell mediated cytotoxicity in vivo. We propose that ADP-ribosylation of CD8-β can regulate the coreceptor function of CD8 in the presence of elevated levels of extracellular NAD(+) .
authors.affiliation: Institute of Immunology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. t.lischke@uke.de
authors.forename: Timo
authors.initials: T
authors.lastname: Lischke
authors.forename: Valéa
authors.initials: V
authors.lastname: Schumacher
authors.forename: Janusz
authors.initials: J
authors.lastname: Wesolowski
authors.forename: Robert
authors.initials: R
authors.lastname: Hurwitz
authors.forename: Friedrich
authors.initials: F
authors.lastname: Haag
authors.forename: Friedrich
authors.initials: F
authors.lastname: Koch-Nolte
authors.forename: Hans-Willi
authors.initials: HW
authors.lastname: Mittrücker
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D016827:CD8 Antigens / Q000276:immunology* / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D002469:Cell Separation; D005434:Flow Cytometry; D008213:Lymphocyte Activation / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D009243:NAD / Q000276:immunology / Q000378:metabolism
chemical_list: D016827:CD8 Antigens; C526846:Cd8b1 protein, mouse; D009243:NAD; D000246:Adenosine Diphosphate Ribose
keywords: Antibodies; Cell surface molecules; T cells; Transgenic/knockout mice