title: HCV-specific lymphocyte responses in individuals with positive anti-HCV but negative HCV-RNA.
abstract: BACKGROUND
  Hepatitis C virus (HCV) status cannot be reliably predicted in anti-HCV positive/HCV-RNA negative individuals who may either have recovered spontaneously or have a false-positive test due to antibody cross-reaction. Investigating T lymphocyte responses in individuals with different HCV status may help understand the cellular immune mechanisms underlying spontaneous recovery, treatment response, and chronicity.
  
  
  OBJECTIVE
  We aimed to determine whether anti-HCV positive, HCV-RNA negative individuals are truly spontaneous recoverers from acute HCV infection.
  
  
  METHODS
  We used enzyme-linked immunosorbent spot (ELISPOT) assay to compare HCV-specific lymphocyte response among anti-HCV positive/HCV-RNA negative individuals, patients with sustained virological response to interferon-γ/ribavirin treatment, and patients with chronic HCV infection.
  
  
  RESULTS
  We found that 83% of anti-HCV positive/HCV-RNA negative individuals without a past medical history of acute icteric hepatitis had an HCV-specific T lymphocyte response in peripheral blood. Lymphocyte responses in these individuals were similar in magnitude to treatment responders unlike patients with chronic HCV whose virus-directed immunity was significantly suppressed.
  
  
  CONCLUSIONS
  Detection of HCV-specific T lymphocyte responses using ELISPOT is a feasible method to ascertain past asymptomatic acute HCV infection.
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Marmara University, School of Medicine, Pendik Training and Research Hospital, Istanbul, Turkey. Electronic address: uluhan.sili@marmara.edu.tr.
authors.forename: Uluhan
authors.initials: U
authors.lastname: Sili
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Abdurrahman
authors.initials: A
authors.lastname: Kaya
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Selda
authors.initials: S
authors.lastname: Aydin
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Nur
authors.initials: N
authors.lastname: Hondur
authors.affiliation: Department of Internal Medicine, Istanbul Medipol University, School of Medicine, Istanbul, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Mert
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Fehmi
authors.initials: F
authors.lastname: Tabak
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Resat
authors.initials: R
authors.lastname: Ozaras
authors.affiliation: Department of Infectious Diseases and Clinical Microbiology, Cerrahpasa School of Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Recep
authors.initials: R
authors.lastname: Ozturk
mesh_terms: D000328:Adult; D000368:Aged; D003955:Diagnostic Tests, Routine / Q000379:methods*; D058501:Enzyme-Linked Immunospot Assay / Q000379:methods*; D005260:Female; D006526:Hepatitis C / Q000175:diagnosis*; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood*; D055815:Young Adult
chemical_list: D018937:Hepatitis C Antibodies; D012367:RNA, Viral
keywords: ELISPOT; False-positive serology; HCV; Spontaneous recovery; T-lymphocyte