title: mu-Opioid receptor is induced by IL-13 within lymph nodes from patients with Sézary syndrome.
abstract: Endogenous opioid peptides mainly produced by neurons are also released by immune cells. They bind to mu- (mu-opioid receptor, MOR), delta-, and kappa-opioid receptors. On the basis of studies on mice showing that MOR is the main mediator of the deleterious effects of opioids on immunity, we wondered whether MOR, absent under normal conditions, is expressed in some pathological situations such as lymphomas. mRNA expression for all three opioid receptors was examined in lymph node biopsy samples from patients with non-Hodgkin's B-cell and T-cell lymphomas. We found that MOR and one of its ligands (enkephalin) are simultaneously expressed almost exclusively in lymph nodes from patients with Sézary cutaneous T cell lymphoma. As MOR was undetectable in circulating malignant T lymphocytes and in normal immune cells, we hypothesized that tumor-released cytokines might induce MOR expression in non-neoplastic lymph node cells. The correlation between mRNA levels of MOR and interleukin-13 (IL-13) within lymph nodes from Sézary patients led us to investigate the ability of IL-13 to upregulate MOR expression in normal immune cell subsets. We found that IL-13 upregulates MOR in activated Langerhans cells. Thus, our data suggest that, under pathological conditions, IL-13 overexpression might allow immune-derived endogenous opioids to down-modulate immune response.
authors.affiliation: INSERM U563, Centre de Physiopathologie de Toulouse-Purpan, Toulouse, France.
authors.forename: Alan
authors.initials: A
authors.lastname: Bénard
authors.forename: Pierre
authors.initials: P
authors.lastname: Cavaillès
authors.forename: Jérôme
authors.initials: J
authors.lastname: Boué
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Chapey
authors.forename: Jagadeesh
authors.initials: J
authors.lastname: Bayry
authors.forename: Catherine
authors.initials: C
authors.lastname: Blanpied
authors.forename: Nicolas
authors.initials: N
authors.lastname: Meyer
authors.forename: Laurence
authors.initials: L
authors.lastname: Lamant
authors.forename: Srini V
authors.initials: SV
authors.lastname: Kaveri
authors.forename: Pierre
authors.initials: P
authors.lastname: Brousset
authors.forename: Gilles
authors.initials: G
authors.lastname: Dietrich
mesh_terms: D001706:Biopsy; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology / Q000502:physiology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000473:pathology / Q000502:physiology; D015870:Gene Expression / Q000276:immunology; D006801:Humans; D007108:Immune Tolerance / Q000502:physiology; D018793:Interleukin-13 / Q000235:genetics* / Q000276:immunology; D007801:Langerhans Cells / Q000473:pathology / Q000502:physiology; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology; D009000:Monocytes / Q000473:pathology / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D017450:Receptors, Opioid, mu / Q000235:genetics* / Q000276:immunology; D012751:Sezary Syndrome / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D012878:Skin Neoplasms / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*
chemical_list: D018793:Interleukin-13; D012333:RNA, Messenger; D017450:Receptors, Opioid, mu