A biomimetic sperm selection device for routine sperm selection

• Published in: Reproductive biomedicine online 2024-09, p.104433, Article 104433
• Main Authors: Vasilescu, Steven A., Goss, Dale M., Gurner, Kathryn H., Kelley, Rebecca L., Mazi, Maria, De Bond, Fabrice K., Lorimer, Jennifer, Horta, Fabrizzio, Parast, Farin Y., Gardner, David K., Nosrati, Reza, Warkiani, Majid E.
• Format: Article
• Language: English
• Subjects: Density gradient centrifugation; DNA fragmentation; Microfluidics; Sperm selection
• ISSN: 1472-6483
• DOI: 10.1016/j.rbmo.2024.104433

Can a biomimetic microfluidic sperm sorter isolate motile spermatozoa while minimizing DNA damage in comparison with density gradient centrifugation (DGC)? This was a two-phase study of 61 men, consisting of a proof-of-concept study with 21 donated semen samples in a university research laboratory, followed by a diagnostic andrology study with 40 consenting patients who presented at a fertility clinic for semen diagnostics. Each sample was split to perform DGC and microfluidic sperm selection (one-step sperm selection with 15 min of incubation) side-by-side. Outcomes evaluated included concentration, progressive motility, and DNA fragmentation index (DFI) of raw semen, and spermatozoa isolated using DGC and the microfluidic device. Results were analysed using Friedman's test for non-parametric data (significant when P < 0.05). DFI values were assessed by sperm chromatin dispersion assay. Spermatozoa isolated using DGC and the microfluidic device showed improved DFI values and motility compared with the raw semen sample in both cohorts. However, the microfluidic device was significantly better than DGC at reducing DFI values in both the proof-of-concept study (P = 0.012) and the diagnostic andrology study (P < 0.001). Progressive motility was significantly higher for spermatozoa isolated using the microfluidic device in the proof-of-concept study (P = 0.0061) but not the diagnostic andrology study. Sperm concentration was significantly lower for samples isolated using the microfluidic device compared with DGC for both cohorts (P < 0.001). Channel-based biomimetic sperm selection can passively select motile spermatozoa with low DNA fragmentation. When compared with DGC, this method isolates fewer spermatozoa but with a higher proportion of progressively motile cells and greater DNA integrity.