title: Impaired thymic output in patients with chronic hepatitis C virus infection.
abstract: Altered T cell homeostasis in chronic hepatitis C virus (HCV) infection has been demonstrated. However, it is unknown whether fibrosis is associated with more perturbed T cell homeostasis in chronic HCV infection. The aim of this study was to examine and compare T cell subsets including recent thymic emigrants (RTE), naive, memory, senescent, apoptotic and IL-7 receptor α (CD127) expressing CD4⁺ and CD8⁺ T cells as well as telomere length and interferon-γ production in HCV-infected patients with (n = 25) and without (n = 26) fibrosis as well as in healthy controls (n = 24). Decreased proportions of CD4⁺ and CD8⁺ RTE were found in HCV-infected patients, especially in HCV-infected patients with fibrosis (14.3% (9.7-23.0) and 28.8% (16.1-40.5), respectively) compared with healthy controls (24.2% (16.3-32.1), P = 0.004 and 39.1% (31.6-55.0), P = 0.010, respectively). Furthermore, HCV-infected patients with fibrosis presented with a higher proportion of CD4⁺ T cells expressing CD127 compared with HCV-infected patients without fibrosis [88.4% (84.5-91.0) versus 83.8% (79.9-86.8), P = 0.016]. Thus, impaired thymic output in HCV infection was found, and high proportion of CD127⁺ T cells may illustrate a compensatory mechanism to preserve T cell counts.
authors.affiliation: Viro-Immunology Research Unit, Department of Infectious Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; Department of Clinical Immunology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: H J
authors.initials: HJ
authors.lastname: Hartling
authors.forename: J C
authors.initials: JC
authors.lastname: Gaardbo
authors.forename: A
authors.initials: A
authors.lastname: Ronit
authors.forename: M
authors.initials: M
authors.lastname: Salem
authors.forename: M
authors.initials: M
authors.lastname: Laye
authors.forename: M R
authors.initials: MR
authors.lastname: Clausen
authors.forename: K
authors.initials: K
authors.lastname: Skogstrand
authors.forename: J
authors.initials: J
authors.lastname: Gerstoft
authors.forename: H
authors.initials: H
authors.lastname: Ullum
authors.forename: S D
authors.initials: SD
authors.lastname: Nielsen
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D003430:Cross-Sectional Studies; D005260:Female; D005355:Fibrosis / Q000276:immunology; D005434:Flow Cytometry; D016174:Hepacivirus / Q000276:immunology* / Q000502:physiology; D019698:Hepatitis C, Chronic / Q000276:immunology* / Q000378:metabolism / Q000821:virology; D054884:Host-Pathogen Interactions / Q000276:immunology; D006801:Humans; D053699:Interleukin-7 Receptor alpha Subunit / Q000276:immunology / Q000378:metabolism; D008099:Liver / Q000276:immunology / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D016615:Telomere / Q000235:genetics / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology* / Q000378:metabolism / Q000821:virology
chemical_list: D053699:Interleukin-7 Receptor alpha Subunit