摘要 |
A method of preparing a conditionally active biologic protein by selecting a wild-type biologic protein, evolving the DNA which encodes the wild-type biologic protein using one or more evolutionary techniques to create mutant DNAs, expressing the mutant DNAs in a eukaryotic cell production host to obtain a mutant protein, subjecting the mutant protein and the wild-type protein to an assay under a normal physiological condition and to an assay under an aberrant condition, selecting a conditionally active mutant protein which exhibits at least one of: (a) a decrease in activity in the assay at the normal physiological condition compared to the wild-type protein, and (b) an increase in activity in the assay under the aberrant condition compared to the wild-type protein; and producing the conditionally active biologic protein in the same eukaryotic cell production host used in the expression step. |