Injecting Embryonic Stem Cells into Eight-Cell-Stage Mouse Embryos.

Area of Science:

• Developmental Biology
• Stem Cell Biology
• Genetics

Background:

• Embryonic stem (ES) cells offer a powerful tool for genetic modification and developmental studies.
• Generating fully ES cell-derived animals is essential for validating genetic modifications and studying gene function.
• Current methods require optimization to improve efficiency and the degree of chimerism.

Purpose of the Study:

• To establish a robust protocol for generating fully ES cell-derived mice (VelociMice) from injected early-stage embryos.
• To optimize post-injection culture conditions for maximizing the production of high-degree chimeras and fully ES cell-derived F0 mice.
• To provide a reproducible method for researchers utilizing ES cell technology.

Main Methods:

• Utilizing eight-cell-stage precompaction embryos from outbred mouse strains.
• Injecting hybrid or inbred embryonic stem (ES) cells into recipient embryos.
• Implementing specific post-injection culture techniques to support embryo development.
• Assessing the contribution of ES cells to the resulting F0 generation.

Main Results:

• Successful generation of F0 mice predominantly or fully derived from the injected ES cells.
• Demonstration that post-injection culture significantly enhances the ratio of fully ES cell-derived mice.
• Achieving high-degree chimeras, indicating successful integration and contribution of ES cells.
• Standardized injection of approximately 50 embryos per ES cell clone for consistent outcomes.

Conclusions:

• The described protocol provides an efficient method for generating fully ES cell-derived mice.
• Optimized post-injection culture is a critical factor for maximizing the success rate of VelociMice production.
• This protocol facilitates the creation of genetically uniform mouse models for research purposes.