title: Buoyant density and sedimentation dynamics of HIV-1 in two density-gradient media for semen processing.
abstract: OBJECTIVE
  To compare buoyant density and sedimentation kinetics of human immunodeficiency virus 1 (HIV-1) in two sperm-washing media, Percoll and Pureception.
  
  
  METHODS
  Laboratory study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  None.
  
  
  METHODS
  Buoyant density and sedimentation kinetics of HIV-1 particles (MOLT-4/LAI strain) were measured in Percoll and Pureception using isopyknic ultracentrifugation and continuous-density-gradient centrifugation.
  
  
  METHODS
  The HIV-1 particles were detected and semiquantified using a reverse transcription polymerase chain reaction (RT-PCR) for HIV-1 RNA.
  
  
  RESULTS
  Calculated buoyant density of HIV-1 was approximately 1.042 in both media in isopyknic centrifugation. However, most HIV-1 particles were found in fractions with specific gravity less than 1.04 in both media, even after 40 minutes of density-gradient centrifugation at 1,600 g. Small viral accumulations were observed at the bottom of the tube in Pureception density gradients.
  
  
  CONCLUSIONS
  Although we found very high efficiency of HIV-1 removal using density-gradient centrifugation, a minute quantity of virus was found at the bottom of the gradient tube when Pureception was used as the medium.
authors.affiliation: Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan. naoaki@sc.itc.keio.ac.jp
authors.forename: Naoaki
authors.initials: N
authors.lastname: Kuji
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yoshii
authors.forename: Toshio
authors.initials: T
authors.lastname: Hamatani
authors.forename: Hideji
authors.initials: H
authors.lastname: Hanabusa
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Shingo
authors.initials: S
authors.lastname: Kato
mesh_terms: D002499:Centrifugation, Density Gradient; D002500:Centrifugation, Isopycnic; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007700:Kinetics; D008297:Male; D011205:Povidone; D012367:RNA, Viral / Q000302:isolation & purification; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012661:Semen / Q000821:virology*; D012822:Silicon Dioxide; D013048:Specimen Handling / Q000379:methods*; D019562:Viral Load
chemical_list: D012367:RNA, Viral; C016039:Percoll; D012822:Silicon Dioxide; D011205:Povidone