Three-Dimensional Rotation of Mouse Embryos

Abstract—Research and clinical applications, such as microin-jection and polar-body biopsy involve 3-D rotation of mammalian oocytes/embryos. In these cell manipulation tasks, the polar body of an embryo/oocyte must be made visible and properly oriented under optical microscopy. Cell rotation in conventional manual op-eration by skilled professionals is based on trial and error, such as through repeated vacuum aspiration and release. The randomness of this manual procedure, its poor reproducibility, and inconsis-tency across operators entail a systematic technique for automated, noninvasive, 3-D rotational control of single cells. This paper re-ports a system that tracks the polar body of mouse embryos in real time and controls multiple motion control devices to conduct automated 3-D rotational control of mouse embryos. Experimental results demonstrated the system’s capability for polar-body orien-tation with a high success rate of 90%, an accuracy of 1.9◦, and an average speed of 22.8 s/cell (versus averagely 40 s/cell in manual operation). Index Terms—Automation, cell manipulation, cell orientation, cell recognition, cell rotation, cell tracking, embryos, oocytes, polar body, 3-D, visual servo. I