Pronuclear microinjection is a technique for creating transgenic mice, an important tool in genetics/genomics and developmental biology research. Due to the inherent difficulties of manipulating delicate mouse embryos, pronuclear injection has been conducted by a handful of professional microinjectionists at Mouse Core Facilities that typically only large research institutions possess. To non-professionals, pronuclear injection of mouse embryos has high skill requirements, a long learning curve, and low success rates. Since regular lab technicians or graduate students are not up to the task, researchers usually turn to professional services provided by Mouse Core Facilities. Advanced Micro and Nanosystems Laboratory (AMNL)
In order to automate pronuclear microinjection, this project under Drs. Yu Sun and Zhe Lu at the University of Toronto developed several key technologies. Based on computer vision microscopy and precision motion control, the system prototype is capable of 3D orienting individual mouse embryos. Dynamic autofocusing techniques were embedded in the system for aligning the holding pipette, pronuclei, and the injection micropipette. Techniques based on motion history images were also implemented and proven effective for detecting the contact between cell and pipette tip. The proof-of-concept system also demonstrated the feasibility of performing pronuclear injection via computer mouse clicking. Building on the results from this project, the team will pursue partnership with industry to further develop the technology for translating it to industry.