What is the real effect of the annexin v columns on human sperm?

OBJECTIVE: To know whether or not the AnnexinV columns reduce the percentage of apoptosis in human sperm. To assess the effect of the AnnexinV columns on the quality of the sperm samples. DESIGN: Retrospective observational trial. MATERIALS AND METHODS: We analyzed the proportion of apoptotic spermatozoa in 25 patients during the first four months of 2013. All subjects were involved in assisted reproduction treatments at Quiron Bilbao. We studied apoptotic spermatozoa in fresh samples, after capacitation and after sperm was filtered by MACS with AnnexinV microbeads (Annexin negative fraction) by using AnnexinV-FITC/ PI assay with flow cytometry. All patients had >15% of apoptotic spermatozoa in capacitated samples (which is our clinical practice cutoff point). Sperm parameters were measured according to the WHO 2010 criteria. RESULTS: The average percentage of apoptosis in fresh samples is 31.88±22.46, 29,23±12.67 in capacitated samples and 13.4±7.53 after MACS. A high decrease was observed in concentration from fresh (30.45±31.09) and capacitated samples (10.14±8.55) comparing to the ones analyzed after MACS (1.42 ±1.39). The percentage of progressive sperm was (47.93±23.87 in fresh 64.16±17.67 in capacitated samples and 52.64±27.33% after MACS) and the percentage of non-progressive spermatozoa (45.73±25.4%, 27.91±17.32 to 39.57±27.81%). CONCLUSION: The percentage of apoptosis in fresh samples is higher, since the seminal plasma has anticapacitating substances and therefore after capacitation this percentage of apoptosis is reduced. Different behaviours were observed in sperm quality parameters. Concentration decreases because apoptotic sperm remains in the filters. A slight increase is observed in the percentage of progressive sperm. Filtering the samples using MACS reduces the percentage of apoptosis but does not make it disappear completely, sowe still need to choose the best spermatozoa to try to get better fertilization rates and better quality embryos.