Patent ID: 8552159

Claim:
A compound comprising a modified carbohydrate complement and a humanized two-chain fusion protein composed of a humanized V H C H1 -hinge-S-human β-glucuronidase chain and of a humanized V L C L chain, which binds specifically to an epitope of a tumor-specific antigen, wherein the modified carbohydrate complement is achieved by chemical qalactosvlation or neuraminidase treatment, wherein the modified carbohydrate complement comprises at least one exposed carbohydrate residue selected from the group consisting of galactose, mannose, N-acetylglucosamine, fucose, N-acetyllactose, glucose, and N-acetylneuraminic acid, wherein said compound has been synthesized in CHO cells, wherein the CHO cells have been selected for a higher level of glycoprotein expression, a higher rate of elimination of glycoprotein from plasma, a higher rate of concentration of the glycoprotein at the tumor-specific antigen and a higher content of high mannose type structures as compared to BHK cells which express said humanized two-chain fusion protein with a different carbohydrate complement, and wherein S is a polypeptide spacer.