Staining of the inner acrosomal membrane of human spermatozoa with concanavalin A lectin as an indicator of potential egg penetration ability.
OBJECTIVE
To determine the sensitivity and functional significance of the fluorescein isothiocyanate concanavalin A (FITC-ConA) staining method of assessment of acrosomal status.


METHODS
Treatments were assessed for their ability to induce human sperm acrosomal loss. Penetration of zona-free human eggs by treated spermatozoa was subsequently determined.


METHODS
Zona-free human eggs were obtained from the Infertility Medical Centre, Richmond, Victoria, Australia.


METHODS
None.


METHODS
None.


METHODS
Acrosomal loss of human spermatozoa was determined at 4 hours and 10 hours of treatment incubation. Penetration of zona-free human eggs was assessed 16 hours after reinsemination.


RESULTS
Human spermatozoa incubated in a strontium- or lanthanum-based medium, or T6 + 10% maternal human serum (HS) supplemented with 12 mM 8-bromo cyclic guanosine 3,5'-monophosphate and 10 mM imidazole for a 4-hour period before transfer to fresh T6 + 10% HS for a further 6 hours, demonstrated a significant increase (P less than 0.05) in acrosomal loss compared with T6 + 10% HS for a total 10-hour incubation. This increase in acrosomal loss with test treatments correlated with an increase in the development of pronuclei of zona-free human eggs (r = +0.98).


CONCLUSIONS
The FITC-ConA staining procedure therefore reflects biological function as assessed by the penetration of zona-free human eggs and consequently provides a further research tool for the investigation of the human sperm acrosome reaction.
Holden
C A
CA
Centre for Early Human Development, Monash Medical Centre, Clayton, Victoria, Australia.
Trounson
A O
AO
D000177:Acrosome / Q000502:physiology*; D003208:Concanavalin A; D003470:Culture Media; D005260:Female; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives; D006801:Humans; D008297:Male; D008566:Membranes / Q000502:physiology; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000502:physiology*; D013194:Staining and Labeling; D013268:Stimulation, Chemical
D003470:Culture Media; C042784:fluorescein isothiocyanate-concanavalin A; D003208:Concanavalin A; D016650:Fluorescein-5-isothiocyanate