abstract |
The present invention is directed generally to cell-targeted cytotoxic constructs comprising a targeting polypeptide, a linking polypeptide and a cytotoxic polypeptide. Preferably, (a) the targeting polypeptide is a R-spondin1 (RSPO1), R-spondin2 (RSPO2) or yoked chorionic gonadotropin (YCG), the linking polypeptide comprises LPXT (SEQ ID NO: 56) or NPXT (SEQ ID NO: 60) as well as others, where X is any amino acid, the linking polypeptide being positioned between the targeting ligand and (c) the cytotoxic moiety is an auristatin or a truncated serine protease, the serine protease having an IIGG (SEQ ID NO: 91), IVGG (SEQ ID NO: 92) or ILGG (SEQ ID NO: 93) at its N-terminus. Such constructs can be used in methods for targeted cell killing such as for treatment cell of proliferative diseases (e.g., cancer). |