Fig. 5
From: Expression of cystatin C in the female reproductive tract and its effect on human sperm capacitation
CST3 inhibits sperm capacitation. Human sperm cultured in EBSS medium was preincubated with or without CST3 (0.125, 0.25, or 0.5 mg/ml) for 20 min, followed by incubation with BSA (3 mg/ml) and sodium bicarbonate (10 mM) for 3 h to induce sperm capacitation. a Cholesterol retained on the sperm was measured. Data are expressed as mean ± SD of three independent experiments. b Phosphorylation levels of sperm protein’s tyrosine residues. A representative anti-phosphotyrosine western blot, out of six experiments, is shown. The relative intensity of the 105-kDa band was quantified using ImageJ, and all values were normalized to the loading control, α-tubulin. *p < 0.05 vs. medium supplemented with BSA and bicarbonate