– Expected to realize biological factories with chickens that lay “golden eggs” –
Researcher: OISHI Isao, Leader, Advanced Genome Design Group, Biomedical Research Institute
The researcher has developed a technique to insert genes into chickens with genome editing. In collaboration with the National Agriculture and Food Research Organization, the researcher has developed technology to produce genetically modified chickens (knock-in chickens) that lay eggs containing a large amount of a useful recombinant protein in the egg white.
Although demand is rising for recombinant proteins such as biopharmaceuticals, production costs remain an issue, so attention has turned to “biological factories” which use genetically modified organisms. Chickens have been seen as a promising candidate for biological factories, but genetic editing of chickens has been difficult. The researcher has worked to develop high precision genetic modification technology for chickens, and has used genetic editing to produce chickens lacking egg white allergen genes.
Using the Crisper-Cass 9 method for genetic editing, the researcher has knocked in the human interferon β gene into the translation starting point of the gene of ovalbumin which is the main proteins in the egg white. Eggs laid by female knock-in chickens contain a large amount of human interferon β (30 – 60 mg) in the egg white, and 100% activity was restored by simple denaturation and rewinding operations. Knock-in chickens can also be bred using male knock-in chickens, so it is possible to reliably produce the recombinant protein from one generation to the next.
In cooperation with Cosmo Bio Co., Ltd., the researcher is developing a purification process with the aim of commercializing a more affordable reagent than conventional products for use in research. In addition to researching recombinant protein production using chicken eggs with genes other than interferon β, he will work to improve the developed technique.