A Simple Method for Transportation of Mouse Embryos Using Microtubes and a Warm Box

Abstract

Generally, transportation of preimplantation embryos without freezing requires incubators that can maintain an optimal culture environment with a suitable gas phase, temperature, and humidity. Such incubators are expensive to transport. We reported previously that normal offspring were obtained when the gas phase and temperature could be maintained during transportation. However, that system used plastic dishes for embryo culture and is unsuitable for long-distance transport of live embryos. Here, we developed a simple low-cost embryo transportation system. Instead of plastic dishes, several types of microtubes—usually used for molecular analysis—were tested for embryo culture. When they were washed and attached to a gas-permeable film, the rate of embryo development from the 1-cell to blastocyst stage was more than 90%. The quality of these blastocysts and the rate of full-term development after embryo transfer to recipient female mice were similar to those of a dish-cultured control group. Next, we developed a small warm box powered by a battery instead of mains power, which could maintain an optimal temperature for embryo development during transport. When 1-cell embryos derived from BDF1, C57BL/6, C3H/He and ICR mouse strains were transported by a parcel-delivery service over 3 days using microtubes and the box, they developed to blastocysts with rates similar to controls. After the embryos had been transferred into recipient female mice, healthy offspring were obtained without any losses except for the C3H/He strain. Thus, transport of mouse embryos is possible using this very simple method, which might prove useful in the field of reproductive medicine.

Animal‐cell culture media: History, characteristics, and current issues

“…Thus, researchers may consider practicing the sterile technique strictly and selecting culture instruments carefully. Washing the instruments with the culture medium immediately before use is recommended in some special cases 151, 152, 153…”

“…An analysis of the concentration by using at least a three-level screening design is necessary to understand such responses with the culture medium immediately before use is recommended in some special cases. [151][152][153] Then, the optimal concentration of component B is determined at the optimal concentration of component A. This strategy, which usually has been used, has a big disadvantage of missing the optimal point because there are some unexamined areas in the range of parameters.…”

Live-cell imaging of mouse preimplantation embryos using a simple closed glass capillary method

“…Mammalian preimplantation embryos have been cultured in various devices, including flasks, fluidic devices, glass tubes, and handmade devices [22][23][24][25] . However, it has been challenging to determine the optimal device for live-cell imaging because these devices cannot be reliably and safely sealed, nor can embryos be easily observed through all devices.…”

Optimised CO2-containing medium for in vitro culture and transportation of mouse preimplantation embryos without CO2 incubator

“…The thermal bottle is inherently mobile and readily available for purchase and has a high heat-retaining property. In our experiments, we used a 500-μL microtube [ 13 ] as a sealed tube instead of a 5-mL plastic tube because a microtube requires a minimal volume of medium to culture embryos. The water temperature in the thermal bottle was measured every 10 min for up to 2 days using a Super Thermochron temperature logger (1922T, KN Laboratories, Osaka, Japan).…”

“…In that study, mouse embryos were transferred to a microtube, which was usually used for molecular analysis, and the tubes were transferred into a plastic bag containing a mixed gas (5% CO 2 , 5% O 2 ). We found that this method enabled the culture of good-quality embryos and also allowed the shipment of live embryos by parcel delivery [ 13 ]. However, because this warm box is not commercially available; its adoption has not yet spread to other laboratories.…”