Clin Exp Reprod Med.  2016 Dec;43(4):199-206. 10.5653/cerm.2016.43.4.199.

Efficient isolation of sperm with high DNA integrity and stable chromatin packaging by a combination of density-gradient centrifugation and magnetic-activated cell sorting

• Chi HJ
• Kwak SJ
• Kim SG
• Kim YY
• Park JY
• Yoo CS
• Park IH
• Sun HG
• Kim JW
• Lee KH

• KMID: 2364656
• DOI: http://doi.org/10.5653/cerm.2016.43.4.199

Abstract

OBJECTIVE
This study was carried out to investigate the correlations of the sperm DNA fragmentation index (DFI) with semen parameters and apoptosis, and to investigate the effects of density-gradient centrifugation (DGC) and magnetic-activated cell sorting (MACS) on reducing the proportion of sperm with DNA fragmentation and protamine deficiency.
METHODS
Semen analysis and a sperm DNA fragmentation assay were performed to assess the correlations between semen parameters and the DFI in 458 semen samples. Sperm with progressive motility or non-apoptosis were isolated by DGC or MACS, respectively, in 29 normozoospermic semen samples. The effects of DGC or MACS alone and of DGC and MACS combined on reducing the amount of sperm in the sample with DNA fragmentation and protamine deficiency were investigated.
RESULTS
The sperm DFI showed a significant correlation (r=-0.347, p<0.001) with sperm motility and morphology (r=-0.114, p<0.05) but not with other semen parameters. The DFI (11.5%±2.0%) of semen samples was significantly reduced by DGC (8.1%±4.1%) or MACS alone (7.4%±3.9%) (p<0.05). The DFI was significantly further reduced by a combination of DGC and MACS (4.1%±1.3%, p<0.05). Moreover, the combination of DGC and MACS (1.6%±1.1%, p<0.05) significantly reduced the protamine deficiency rate of semen samples compared to DGC (4.4%±3.2%) or MACS alone (3.4%±2.2%).
CONCLUSION
The combination of DGC and MACS may be an effective method to isolate high-quality sperm with progressive motility, non-apoptosis, high DNA integrity, and low protamine deficiency in clinical use.

Keyword

Apoptosis; Centrifugation, Density gradient; Magnetic-activated cell sorting; Protamine deficiency; Sperm DNA fragmentation index

MeSH Terms

Apoptosis
Centrifugation*
Centrifugation, Density Gradient
Chromatin*
DNA Fragmentation
DNA*
Methods
Product Packaging*
Semen
Semen Analysis
Sperm Motility
Spermatozoa*
Chromatin
DNA