Perfringolysin O as a useful tool to study human sperm physiology

POCOGNONI, CRISTIÁN A. ; DE BLAS, GERARDO A; HEUCK, ALEJANDRO P; BELMONTE, SILVIA A; MAYORGA, LUIS S

FERTILITY AND STERILITY

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2013 p. 99 - 106

0015-0282

Objective: To evaluate perfringolysin O, a cholesterol-dependent pore-forming cytolysin, as atool to study several aspects of human sperm physiology.Design: Prospective study.Setting: Basic research laboratory.Patient(s): Human semen samples with normal parameters obtained from healthy donors.Interventions: Interaction of recombinant perfringolysin O with human spermatozoa.Main Outcome Measures: Assessment of perfringolysin O binding to spermatozoa. Tests foracrosome and plasma membrane integrity. Acrosomal exocytosis assaysResults: Perfringolysin O associated to human spermatozoa at 4ºC. The binding was sensitiveto changes in cholesterol concentrations and distribution occurring in the plasma membrane ofthese cells during capacitation. When perfringolysin O-treated sperm were incubated at 37ºC,the plasma membrane became permeable whereas the acrosome membrane remained intact.Permeabilized spermatozoa were able to respond to exocytic stimuli. The process wasinhibited 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 theactive sterol fraction present in the sperm plasma membrane. The toxin can be used for theefficient and selective permeabilization of this membrane rendering a flexible experimentalmodel suitable for studying molecular processes occurring in the sperm cytoplasm.