title: Perfringolysin O as a useful tool to study human sperm physiology.
abstract: OBJECTIVE
  To evaluate perfringolysin O, a cholesterol-dependent pore-forming cytolysin, as a tool to study several aspects of human sperm physiology.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Basic research laboratory.
  
  
  METHODS
  Human semen samples with normal parameters obtained from healthy donors.
  
  
  METHODS
  Interaction of recombinant perfringolysin O with human spermatozoa.
  
  
  METHODS
  Assessment of perfringolysin O binding to spermatozoa, tests for acrosome and plasma membrane integrity, and acrosomal exocytosis assays.
  
  
  RESULTS
  Perfringolysin O associated with human spermatozoa at 4°C. The binding was sensitive to changes in cholesterol concentrations and distribution occurring in the plasma membrane of these cells during capacitation. When perfringolysin O-treated sperm were incubated at 37°C, the plasma membrane became permeable, whereas the acrosome membrane remained intact. Permeabilized spermatozoa were able to respond to exocytic stimuli. The process was inhibited by proteins that interfere with membrane fusion, indicating that large molecules, including antibodies, were able to permeate into the spermatozoa.
  
  
  CONCLUSIONS
  PFO is a useful probe to assess changes in the amount and distribution of the active sterol fraction present in the sperm plasma membrane. The toxin can be used for the efficient and selective permeabilization of this membrane, rendering a flexible experimental model suitable for studying molecular processes occurring in the sperm cytoplasm.
authors.affiliation: IHEM (CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina.
authors.forename: Cristián A
authors.initials: CA
authors.lastname: Pocognoni
authors.affiliation: IHEM (CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina.
authors.forename: Gerardo A
authors.initials: GA
authors.lastname: De Blas
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Massachusetts.
authors.forename: Alejandro P
authors.initials: AP
authors.lastname: Heuck
authors.affiliation: IHEM (CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina.
authors.forename: Silvia A
authors.initials: SA
authors.lastname: Belmonte
authors.affiliation: IHEM (CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina. Electronic address: lmayorga@fcm.uncu.edu.ar.
authors.forename: Luis S
authors.initials: LS
authors.lastname: Mayorga
mesh_terms: D000177:Acrosome / Q000187:drug effects / Q000502:physiology; D001427:Bacterial Toxins / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology; D005089:Exocytosis / Q000187:drug effects; D006460:Hemolysin Proteins / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D054353:Perforin / Q000494:pharmacology*; D011446:Prospective Studies; D013075:Sperm Capacitation / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects* / Q000502:physiology*
chemical_list: D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D054353:Perforin; C020452:Clostridium perfringens theta-toxin