Presentation Authors: Alex Jafek*, Hayden Brady, Haidong Feng, Jim Hotaling, Douglas Carrell, Bruce Gale, Raheel Samuel, Kenneth Aston, Timothy Jenkins, Salt Lake City, UT
Introduction: Density gradient centrifugation (DGC) is the clinical gold standard for clinical sperm preparation for normal samples. However, the preparation technique is time consuming, requires a trained technician, and exposes the sperm to large centrifugal forces. In this work, we aim to develop a novel microfluidic device to isolate motile sperm from the ejaculate for use in artificial insemination that will be faster and gentler than DGC.
Methods: Participants were recruited from our Andrology clinic and were required to adhere to standard collection instructions. To facilitate a paired analysis, semen samples were divided into two equal aliquots and processed either through DGC (column with a 90% isolate and 35% isolate layer) or through our microfluidic device. Following processing, samples were assessed for the total number of motile sperm present in the final prepared sample and differences were reported between the two preparations. Additionally, we assessed the capacity of the microfluidic device to remove round cells from the initial sample following processing.
Results: Our results indicate that our microfluidic device effectively retains more motile sperm than the DGC procedure. Specifically, processing the sperm with the microfluidic device allows us to recover 60-80% of the motile sperm depending on operating protocol. In addition, the sperm experience significantly less force in the microfluidic device (~6.2g for less than one second) than through a DGC sperm preparation (400g for 25 minutes). Further, the microfluidic separation also has the ability to remove virtually all round cells from the sample.
Conclusions: Our microfluidic device is capable of preparing a sperm sample for insemination by capturing 60-80% of all motile sperm that were present in the original sample and removing the majority of somatic cells. The microfluidic approach merits investigation as a replacement for a DGC because it is faster, gentler, and retains a higher portion of motile cells than DGC. Further, the system is compatible with automation, which could allow clinics in remote areas to begin to perform IUI without the technician/lab that is support currently required.
Source of Funding: NSF SBIR