title: Plasma interleukin-27 (IL-27) levels are not modulated in patients with chronic HIV-1 infection.
abstract: OBJECTIVE
  IL-27 is an immunomodulatory cytokine with potent anti-HIV properties in PBMCs, CD4+ T cells, macrophages and immature dendritic cells. Previous smaller studies have suggested that HIV-1 infection may alter IL-27 and influence HIV-1 pathogenesis. The aim of this study was to examine the relationship between plasma IL-27 levels in a well-characterised cohort of HIV-1 infected patients.
  
  
  METHODS
  Patients were stratified into four groups based on HIV-1 viral load and matched according to age, gender and those receiving antiretroviral treatment. IL-27 levels and C-reactive protein (CRP) were measured using electrochemiluminescence assays. D-dimer and CD4+ T cell counts were measured using an Enzyme Linked Fluorescence Assay and FACS, respectively. sCD14 and sCD163 were measured using ELISA. HIV-1 viral load was measured by bDNA or qRT-PCR assays.
  
  
  RESULTS
  Plasma IL-27 levels were measured in 505 patients (462 HIV+, 43 controls). The mean level (±SEM) of IL-27 in controls was 2990.7±682.1 pg/ml, in the <50 copies/ml group it was 2008.0±274.8 pg/ml, in the 51-10,000 copies group it was 1468.7±172.3 pg/ml, in the 10,001-100,000 copies/ml group it was 1237.9±127.3 pg/ml and in the >100,000 copies/ml group it was 1590.1±223.7 pg/ml. No statistically significant difference in IL-27 levels between groups were seen. There were no correlations noted between IL-27 and HIV-1 viral load or CD4+ T cell counts. There was a small correlation noted between D-dimer and IL-27 (Spearman r = 0.09, p = 0.03) and sCD163 and IL-27 (Spearman r = 0.12, p = 0.005). No correlation was observed between IL-27 and CRP or sCD14 levels.
  
  
  CONCLUSIONS
  This is the largest study examining the levels of plasma IL-27 in HIV-1 infection. While IL-27 levels are not significantly altered in HIV-1 infection compared to uninfected controls there may be a small association between IL-27 and D-dimer levels and IL-27 and sCD163 levels.
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America; Department of Clinical Immunology, Western Sydney Local Health District, Sydney, Australia; Sydney Medical School, University of Sydney, Sydney, Australia; School of Medicine, University of Western Sydney, Sydney, Australia.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Swaminathan
authors.affiliation: Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Zonghui
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Adam W
authors.initials: AW
authors.lastname: Rupert
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Jeanette M
authors.initials: JM
authors.lastname: Higgins
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Robin L
authors.initials: RL
authors.lastname: Dewar
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Randy
authors.initials: R
authors.lastname: Stevens
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Rehm
authors.affiliation: Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Julia A
authors.initials: JA
authors.lastname: Metcalf
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Baseler
authors.affiliation: Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: H Clifford
authors.initials: HC
authors.lastname: Lane
authors.affiliation: Applied and Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America.
authors.forename: Tomozumi
authors.initials: T
authors.lastname: Imamichi
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016022:Case-Control Studies; D002908:Chronic Disease; D015331:Cohort Studies; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D015658:HIV Infections / Q000097:blood* / Q000188:drug therapy / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D064094:Interleukin-27 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000378:metabolism* / Q000821:virology; D011379:Prognosis; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D015415:Biomarkers; D064094:Interleukin-27; D002097:C-Reactive Protein