title: Direct visualization of HIV-enhancing endogenous amyloid fibrils in human semen.
abstract: Naturally occurring fragments of the abundant semen proteins prostatic acid phosphatase (PAP) and semenogelins form amyloid fibrils in vitro. These fibrils boost HIV infection and may play a key role in the spread of the AIDS pandemic. However, the presence of amyloid fibrils in semen remained to be demonstrated. Here, we use state of the art confocal and electron microscopy techniques for direct imaging of amyloid fibrils in human ejaculates. We detect amyloid aggregates in all semen samples and find that they partially consist of PAP fragments, interact with HIV particles and increase viral infectivity. Our results establish semen as a body fluid that naturally contains amyloid fibrils that are exploited by HIV to promote its sexual transmission.
authors.affiliation: Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
authors.forename: Shariq M
authors.initials: SM
authors.lastname: Usmani
authors.affiliation: Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
authors.forename: Onofrio
authors.initials: O
authors.lastname: Zirafi
authors.affiliation: Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
authors.forename: Janis A
authors.initials: JA
authors.lastname: Müller
authors.affiliation: 1] Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany [2] Kinderwunsch-Zentrum Ulm, 89077 Ulm, Germany.
authors.forename: Nathallie L
authors.initials: NL
authors.lastname: Sandi-Monroy
authors.affiliation: Institute of Pharmaceutical Biotechnology, Ulm University, 89081 Ulm, Germany.
authors.forename: Jay K
authors.initials: JK
authors.lastname: Yadav
authors.affiliation: Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, 89081 Ulm, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Meier
authors.affiliation: Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, 89081 Ulm, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Weil
authors.affiliation: 1] Department of Urology, University of California, San Francisco, California 94158, USA [2] Gladstone Institute of Virology and Immunology, University of California at San Francisco, San Francisco, California 94158, USA.
authors.forename: Nadia R
authors.initials: NR
authors.lastname: Roan
authors.affiliation: 1] Gladstone Institute of Virology and Immunology, University of California at San Francisco, San Francisco, California 94158, USA [2] Departments of Medicine and Microbiology and Immunology, University of California, San Francisco, California 94158, USA.
authors.forename: Warner C
authors.initials: WC
authors.lastname: Greene
authors.affiliation: Central Electron Microscopy Facility, Ulm University, 89081 Ulm, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Walther
authors.affiliation: IFM-Department of Chemistry, Linköping University, SE-581 83 Linköping, Sweden.
authors.forename: K Peter R
authors.initials: KP
authors.lastname: Nilsson
authors.affiliation: IFM-Department of Chemistry, Linköping University, SE-581 83 Linköping, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Hammarström
authors.affiliation: Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260, USA.
authors.forename: Ronald
authors.initials: R
authors.lastname: Wetzel
authors.affiliation: HIV/AIDS Division, San Francisco General Hospital, University of California, San Francisco, California 94158, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Pilcher
authors.affiliation: Kinderwunsch-Zentrum Ulm, 89077 Ulm, Germany.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Gagsteiger
authors.affiliation: Institute of Pharmaceutical Biotechnology, Ulm University, 89081 Ulm, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Fändrich
authors.affiliation: Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Kirchhoff
authors.affiliation: Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Münch
mesh_terms: D000135:Acid Phosphatase; D000682:Amyloid / Q000378:metabolism* / Q000648:ultrastructure; D015658:HIV Infections / Q000378:metabolism* / Q000821:virology; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism; D012661:Semen / Q000378:metabolism* / Q000821:virology; D029607:Seminal Vesicle Secretory Proteins / Q000378:metabolism
chemical_list: D000682:Amyloid; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen; D000135:Acid Phosphatase; C428439:prostatic acid phosphatase; D017027:Protein Tyrosine Phosphatases