Recording and sorting live human sperm undergoing acrosome reaction.

OBJECTIVE

To develop and evaluate a method to detect acrosome reaction (AR) in live human sperm.

DESIGN

Prospective study.

SETTING

Basic research laboratory.

PATIENT(S): Human semen samples with normal parameters obtained from healthy donors.

INTERVENTION(S): Acrosome reaction assays.

MAIN OUTCOME MEASURE(S): Fluorescence assessment of AR.

RESULT(S): Evaluating acrosomal exocytosis in live human sperm is challenging. In this study, we report that in reacting sperm, Pisum sativum agglutinin conjugated to fluorescein isothiocyanate rapidly permeates into the acrosome when fusion pores open and stabilizes the acrosomal matrix, preventing the dispersal of the granule contents.

CONCLUSION(S): Fluorescent Pisum sativum agglutinin can be used to visualize AR in real time, to determine the percentage of sperm undergoing exocytosis upon stimulation, and to separate the population of reacting sperm by flow cytometry.