Department of Mathematics and Physics E. de Giorgi, University of Salento, Via per Arnesano, 73100 Lecce, Italy; Institute of Nanotechnology, CNR NANOTEC, Via per Monteroni, 73100 Lecce, Italy; Scuola Superiorie ISUFI (Istituto Superiore Universitario di Formazione Interdisciplinare), University of Salento, Via per Arnesano, 73100 Lecce, Italy.
Institute of Nanotechnology, CNR NANOTEC, Via per Monteroni, 73100 Lecce, Italy.
Biotechnol Adv. 2020 May-Jun;40:107498. doi: 10.1016/j.biotechadv.2019.107498. Epub 2019 Dec 11.
Male infertility often involves idiopathic or unknown causes, leading to an increasing demand for assisted reproduction technologies (ART). Conventional sperm sorting techniques rely on centrifugation steps that are known to cause oxidative stress and consequently damage cells. Alternative novel techniques have been introduced but offer disadvantages that need to be overcome. These techniques are also employed to increase the number and the quality of subjects in the animal breeding industry, to obtain purebred subjects or to preserve endangered animal species. Microfluidics deals with the manipulation of small amounts of volume within a microdevice known as lab-on-a-chip (LOC), which offers rapid analyses, ease of use, small reagent sample volumes, high-throughput processing and wide reproducibility owing to automation and standardization. As the LOC allows gamete handling within a microenvironment that strictly mimics physiological in vivo conditions and avoids centrifugation steps and long processing time, the use of microfluidics for sperm sorting and selection have been proposed during the last 15 years and is currently under investigation. Moreover, LOC technologies to sort, identify and analyse other kinds of cells could be transferred to sperm selection and analysis, thus opening the way to a novel approach to the sperm cell selection and manipulation. This review describes the techniques routinely performed in human and animal clinical practice for sorting good-quality sperm for in vitro fertilization procedures, and focuses on the positive and negative aspects of each method. Emerging microfluidic devices, recently proposed for sperm selection, are also described and, when possible, compared with standard methods.
男性不育症常涉及特发性或未知原因，导致对辅助生殖技术（ART）的需求不断增加。传统的精子分选技术依赖于离心步骤，已知这些步骤会导致氧化应激，从而损害细胞。已经引入了替代的新型技术，但它们也存在需要克服的缺点。这些技术还被用于增加动物繁殖行业的个体数量和质量，以获得纯种个体或保护濒危动物物种。
微流控技术涉及在称为芯片实验室（LOC）的微器件内操纵小体积量，由于自动化和标准化，它提供快速分析、易于使用、小试剂样品体积、高通量处理和广泛的可重复性。由于 LOC 允许在严格模拟生理体内条件的微环境中处理配子，并避免离心步骤和长时间的处理时间，因此在过去 15 年中提出了使用微流控技术进行精子分选和选择，目前正在进行研究。此外，用于分选、鉴定和分析其他类型细胞的 LOC 技术可以转移到精子选择和分析中，从而为精子细胞选择和操作开辟了新途径。
本综述描述了在人类和动物临床实践中常规进行的用于体外受精程序分选优质精子的技术，并重点介绍了每种方法的优缺点。还描述了最近提出的用于精子选择的新兴微流控装置，并在可能的情况下与标准方法进行了比较。
