Expression vectors encoding bispecific fusion proteins and methods of producing biologically active bispecific fusion proteins in a mammalian cell

摘要

The present invention provides an expression vector encoding bispecific fusion protein.

<Paragraphs id="pa02" num="0002" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">In one embodiment the expression vector encodes a monospecific fusion protein, which vector comprises a recombinant monospecific single chain cassette comprising a DNA sequence encoding a first binding domain capable of binding a cell surface antigen.

<Paragraphs id="pa03" num="0003" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">The expression vector encodes a bispecific fusion protein, which vector comprises a recombinant bispecific single chain cassette comprising a DNA sequence encoding a first binding domain capable of binding a cell surface antigen and a DNA sequence encoding a second binding domain capable of binding a cell surface antigen, each domain capable of binding a different antigen.

<Paragraphs id="pa04" num="0004" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">The present invention also provides a method for producing a biologically active bispecific fusion protein in a mammalian cell. This method comprises: (a) transfecting the mammalian cell with the recombinant expression vector of the invention; (b) culturing the mammalian cell so transfected in step (a); and (c) recovering the biologically active bispecific fusion protein so as produced by the cultured mammalian cell.