Fig. 9. Acrosomal status of sperm undergoing GST aggregation. To visualise aggregation of sperm-surface GSTs, capacitated sperm were incubated with SZP (10 µg/ml/10⁷ sperm) at 37°C, and aliquots of sperm were fixed at different time points in 4% buffered paraformaldehyde. The movement of the GST molecules was visualised by staining with FITC-labelled secondary antibody (1:500). Pisum sativum agglutinin (PSA) conjugated to rhodamine (1:100) was used to stain the same samples to visualise the status of the acrosome. (A) Aggregation of sperm GST Pi on goat sperm surface after treatment with SZP at a 60 minute time point. B shows the same spermatozoa as in microphotograph A stained with rhodamine-labelled Pisum sativum agglutinin showing the intactness of the entire acrosome at 1 hour. (C) Aggregation of sperm GST Mu on goat sperm surface after treatment with SZP at a 60 minute time point. (D) The same spermatozoa as in microphotograph C stained with rhodamine-labelled Pisum sativum agglutinin showing the intactness of the entire acrosome at 1 hour. Bar, 10 µm.