The Institute of Engineering in Medicine, University of California, San Diego, CA, USA.
Wiley Interdiscip Rev Syst Biol Med. 2011 Jan-Feb;3(1):36-47. doi: 10.1002/wsbm.106.
Optical trapping is a noninvasive biophotonic tool that has been developed to study the physiological and biomechanical properties of cells. The custom-designed optical system is built to direct near-infrared laser light into an inverted microscope to create a single-point three-dimensional gradient laser trap at the microscope focal point. A real-time automated tracking and trapping system (RATTS) is described that provides a remote user-friendly robotic interface. The combination of laser tweezers, fluorescent imaging, and RATTS can measure sperm swimming speed and swimming force simultaneously with mitochondrial membrane potential (MMP). The roles of two sources of adenosine triphosphate in sperm motility/energetics are studied: oxidative phosphorylation, which occurs in the mitochondria located in the sperm midpiece, and glycolysis, which occurs along the length of the sperm tail (flagellum). The effects of glucose, oxidative phosphorylation inhibitors, and glycolytic inhibitors on human sperm motility are studied. This combination of photonic physical and engineering tools has been used to examine the evolutionary effect of sperm competition in primates. The results demonstrate a correlation between mating type and sperm motility: sperm from polygamous (multi-partner) primate species swim faster and with greater force than sperm from polygynous (single partner) primate species. In summary, engineering and biological systems are combined to provide a powerful interdisciplinary approach to study the complex biological systems that drive the sperm toward the egg.
光学捕获是一种非侵入性的生物光子工具，用于研究细胞的生理和生物力学特性。定制的光学系统旨在将近红外激光引导到倒置显微镜中，在显微镜焦点处创建单点三维梯度激光阱。描述了一种实时自动跟踪和捕获系统（RATTS），它提供了一个远程用户友好的机器人界面。激光镊子、荧光成像和 RATTS 的组合可以同时测量精子的游动速度和游动力以及线粒体膜电位（MMP）。研究了两种来源的三磷酸腺苷在精子运动/能量学中的作用：位于精子中段的线粒体中的氧化磷酸化，以及沿着精子尾部（鞭毛）发生的糖酵解。研究了葡萄糖、氧化磷酸化抑制剂和糖酵解抑制剂对人精子运动的影响。这种光物理和工程工具的组合已被用于研究灵长类动物精子竞争的进化效应。结果表明，交配类型与精子运动之间存在相关性：来自多配偶（多伴侣）灵长类物种的精子游动速度更快，游动力度更大，而来自一夫一妻（单一伴侣）灵长类物种的精子则较慢且力度较小。总之，工程和生物系统相结合，为研究推动精子向卵子运动的复杂生物系统提供了一种强大的跨学科方法。
