title: Distinct cytokine patterns in semen influence local HIV shedding and HIV target cell activation.
abstract: BACKGROUND
  Semen is the main vector for human immunodeficiency virus (HIV) transmission from men to women. We investigated the influence of cytokines in semen on local HIV burden and activated T cells.
  
  
  METHODS
  Blood and semen were collected from 42 HIV-negative and 38 HIV-positive men. Concentrations of 20 cytokines were measured by Luminex, and frequencies of activated T cells were measured by flow cytometry.
  
  
  RESULTS
  Semen contained higher concentrations of proinflammatory (monocyte chemotactic protein-1, interleukin [IL]-8, IL-6, Fractalkine, macrophage inflammatory protein (MIP)-1β, granulocyte macrophage colony-stimulating factor) and adaptive cytokines (IL-7 and IL-15) and higher frequencies of activated T cells compared to blood. Plasma IL-2, eotaxin, MIP-1β, and IL-15 and semen eotaxin and granulocyte colony-stimulating factor (G-CSF) concentrations were associated with T-cell activation. Cytokines in semen were highly coregulated in HIV-negative men; however, this network was disrupted during HIV infection. Several cytokines in semen correlated with HIV shedding (G-CSF, tumor necrosis factor-alpha [TNF-α], interferon-gamma [IFN-γ], IL-10).
  
  
  CONCLUSIONS
  Higher levels of inflammation and T-cell activation were observed in semen compared with blood. Seminal G-CSF, which influences neutrophil survival, T-cell function, and dendritic cell activation, was associated with T-cell activation and HIV shedding and may be an important target for reducing HIV shedding or risk.
authors.affiliation: Institute of Infectious Disease and Molecular Medicine and Division of Medical Virology, University of Cape Town.
authors.forename: Abraham J
authors.initials: AJ
authors.lastname: Olivier
authors.forename: Lindi
authors.initials: L
authors.lastname: Masson
authors.forename: Katharina
authors.initials: K
authors.lastname: Ronacher
authors.forename: Gerhard
authors.initials: G
authors.lastname: Walzl
authors.forename: David
authors.initials: D
authors.lastname: Coetzee
authors.forename: David A
authors.initials: DA
authors.lastname: Lewis
authors.forename: Anna-Lise
authors.initials: AL
authors.lastname: Williamson
authors.forename: Jo-Ann S
authors.initials: JA
authors.lastname: Passmore
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Burgers
mesh_terms: D000328:Adult; D016207:Cytokines / Q000378:metabolism*; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D008213:Lymphocyte Activation / Q000502:physiology; D008297:Male; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction; D012661:Semen / Q000378:metabolism / Q000821:virology*; D013019:South Africa; D013601:T-Lymphocytes / Q000276:immunology*; D017201:Virus Shedding / Q000502:physiology*; D055815:Young Adult
chemical_list: D016207:Cytokines
keywords: HIV; T cells; activation; cytokines; inflammation; semen