title: Toll-like receptor (TLR) expression on CD4+ and CD8+ T-cells in patients chronically infected with hepatitis C virus.
abstract: Toll-like receptor (TLR) expression on T-cells and the signalling pathways that lead to the production of cytokines may limit antigen-specific T-cell responses. Here, expression of TLR and retinoic acid inducible gene I (RIG-I) on T-cells were evaluated in patients chronically infected with hepatitis C virus (HCV), before and during pegylated interferon-alpha and ribavirin therapy. Expression of TLR2,3,4,7,9 and retinoic acid inducible gene (RIG)-I on different CD4(+) and CD8(+) T-cell sub-populations (naïve: CD45RA(+)CD57(-); central memory: T(CM) CD45RA(-)CD57(-); effector memory: T(EM) CD45RA(-)CD57(+) and terminally differentiated effector memory: T(EMRA) CD45RA(+)CD57(+)) were measured by flow cytometry. TLR7, TLR9 and RIG-I expression on CD4(+) T-cells and RIG-I expression on CD8(+) T-cells was higher in patients than healthy controls. Therapy increased expression of TLR2, TLR4 and TLR9 and this was observed for all T-cell sub-populations. Evaluation of TLR expression at baseline did not identify patients able to achieve sustained virological response following therapy.
authors.affiliation: School of Pathology and Laboratory Medicine, University of Western Australia, Australia.
authors.forename: Talia
authors.initials: T
authors.lastname: Hammond
authors.forename: Silvia
authors.initials: S
authors.lastname: Lee
authors.forename: Mark W
authors.initials: MW
authors.lastname: Watson
authors.forename: James P
authors.initials: JP
authors.lastname: Flexman
authors.forename: Wendy
authors.initials: W
authors.lastname: Cheng
authors.forename: Sonia
authors.initials: S
authors.lastname: Fernandez
authors.forename: Patricia
authors.initials: P
authors.lastname: Price
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D002469:Cell Separation; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D016174:Hepacivirus / Q000276:immunology* / Q000472:pathogenicity; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007156:Immunologic Memory; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage; D011971:Receptors, Immunologic; D011994:Recombinant Proteins; D012254:Ribavirin / Q000008:administration & dosage; D051193:Toll-Like Receptors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011971:Receptors, Immunologic; D011994:Recombinant Proteins; D051193:Toll-Like Receptors; D011092:Polyethylene Glycols; D012254:Ribavirin; C452820:RIGI protein, human; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; C100416:peginterferon alfa-2a