Viscous Cervical Environment-on-a-Chip for Selecting High-Quality Sperm from Human Semen

Manhee Lee, Jin Woo Park, Dongwon Kim, Hyojeong Kwon, Min Jeong Cho, Eun Ji Lee, Tai Eun Shin, Dae Keun Kim, Seungki Lee, Do Gyeung Byeun, Jung Jae Ko, Jae Ho Lee (+1 others)
2021 Biomedicines  
When ejaculated sperm travels through the vagina to the uterus, mucus secreted by the cervical canal generally filters out sperm having low motility and poor morphology. To investigate this selection principle in vivo, we developed a microfluidic sperm-sorting chip with a viscous medium (polyvinylpyrrolidone: PVP) to imitate the biophysical environment mimic system of the human cervical canal. The material property of the PVP solution was tuned to the range of viscosities of cervical mucus
more » ... micro-viscometry. The selection of high-quality human sperm was experimentally evaluated in vitro and theoretically analyzed by the convection-diffusion mechanism. The convection flow is shown to be dominant at low viscosity of the medium used in the sperm-sorting chip when seeded with raw semen; hence, the raw semen containing sperm and debris convectively flow together with suppressed relative dispersions. Also, it was observed that the sperm selected via the chip not only had high motilities but also normal morphologies and high DNA integrity. Therefore, the biomimetic sperm-sorting chip with PVP medium is expected to improve male fertility by enabling the selection of high-quality sperm as well as uncovering pathways and regulatory mechanisms involved in sperm transport through the female reproductive tract for egg fertilization.
doi:10.3390/biomedicines9101439 pmid:34680555 fatcat:bzsvexe75zatjgnynqwlc44wky