title: The value of interleukin 6 as a peripheral diagnostic marker in schizophrenia.
abstract: BACKGROUND
  Associations between a pro-inflammatory state and schizophrenia have been one of the more enduring findings of psychiatry, with various lines of evidence suggesting a compelling role for IL-6 in the underlying pathogenesis of schizophrenia.
  
  
  METHODS
  In this study, we examined IL-6 mRNA levels by real-time RT-PCR from fresh extracted peripheral blood mononuclear cells (PBMC) in normal controls and participants with schizophrenia.
  
  
  RESULTS
  We found that peripheral PBMC IL-6 mRNA levels, in the absence of any other information, reliably discriminated between a diagnosis of schizophrenia and normal controls. Furthermore, in participants with schizophrenia, we also found elevated levels of IL-6 mRNA with earlier ages of illness onset and worse positive symptom presentation, as measured by the Positive and Negative Syndrome Scale.
  
  
  CONCLUSIONS
  These findings provide important and continued support for a pathophysiological role of inflammation in patients with schizophrenia. Future utilization of peripheral IL-6 mRNA levels could be clinically useful during an initial diagnosis and help tailor individualized treatment plans for patients with schizophrenia.
authors.affiliation: The Psychiatric Institute, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL, 60612, USA.|Department of Psychiatry, The University of California, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093, USA.
authors.forename: Kayla A
authors.initials: KA
authors.lastname: Chase
authors.affiliation: Department of Neurobiology, The University of Chicago, 5812 S. Ellis, Chicago, IL, 60637, USA.
authors.forename: Jackson J
authors.initials: JJ
authors.lastname: Cone
authors.affiliation: The Psychiatric Institute, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL, 60612, USA.
authors.forename: Cherise
authors.initials: C
authors.lastname: Rosen
authors.affiliation: The Psychiatric Institute, University of Illinois at Chicago, 1601 W. Taylor St., Chicago, IL, 60612, USA. rsharma@psych.uic.edu.|Jesse Brown Veterans Affairs Medical Center, 820 South Damen Avenue (M/C 151), Chicago, IL, 60612, USA. rsharma@psych.uic.edu.
authors.forename: Rajiv P
authors.initials: RP
authors.lastname: Sharma
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D007963:Leukocytes, Mononuclear / Q000737:chemistry; D008297:Male; D012333:RNA, Messenger / Q000097:blood; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000097:blood*
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D012333:RNA, Messenger
keywords: Biomarker; Interleukin-6; Lymphocyte; PBMC; Schizophrenia