? Currently, chimeric chickens are made by injecting blastodermal cells or chicken embryonic stem cells into stage X recipient embryos, but the frequency and the level of chimerism is variable and not predictable. We are developing a universal recipient that contributes minimally, so that the contribuion of donor dervied celld to the resulting chimera is constantly high and predictable. ? ? In phase I of this SBIR project, a lentiviral vector for the universal recipient chicken line and for a GFP control line was generated and evaluated by transducing stage X chicken embryos with a lentiviral vector. The results clearly demonstrated the feasibility of a lentiviral approach for the establishment of the universal recipient transgenic chicken lines. ? ? In phase II of this grant application, we plan to generate the universal recipient chicken lines using the lentiviral approach. The project is unique and innovative because it seeks to establish a reliable and reproducible method of compromising the recipient embryos to consistently yield high-grade chimeras and allow the production of significant amounts of protein per egg in a short period of time. ? ? ?
