To date, chimeric chickens are made by injecting blastodermal cells or embryonic stem cells into the stage X embryo (recipient), but the frequency and level of chimerism is variable and unpredictable (Petitte et al., 1990; Petitte et al., 1993). We are developing a universal recipient that contributes minimally, so that the contribution of donor derived cells to the resulting chimera is constantly high and predictable. These high-grade chimeras can be used to produce biopharmaceutical proteins in chicken eggs as soon as the chimeras commence laying and before they transmit the gene encoding the biopharmaceutical protein to the next generation. In addition, these high-grade chimeras will allow the production of biopharmaceutical proteins if the transgene interferes with their ability to reproduce. The end point of this research is a robust system to produce high-grade chimeras in highly predictable way. Using this system biopharmaceutical proteins can be produced quickly, in a scalable system and at minimal cost. ? ?
