Processing of boar spermatozoa with cold PBS induces an increase in p32

We aimed to investigate the impact of processing boar spermatozoa with phosphate-buffered saline (PBS) at 4 ˚C on acrosomal integrity and increase in phosphorylation in tyrosine residues of the p32 protein. Following cold PBS washing, we observed a significant increase in p32 levels and in the proportion of non-viable spermatozoa with compromised acrosomal integrity compared to sperm washing using PBS at room temperature. Interestingly, this increase in p32 was effectively inhibited when cold PBS was supplemented with 1 mM AEBSF, a serine protease inhibitor. Our findings suggest that the induction of p32 in response to cold PBS washing in boar spermatozoa is associated with enhanced protease activity in dead spermatozoa.