TITLE:
Construction, expression and binding specificity of bispecific CD3 × VEGFR-2 and CD3 × NCAM antibodies in the single chain and diabody format
AUTHORS:
Anke Kopacek, Thomas Böldicke, Sarah Lergenmüller, Frank Berthold, Markus Jensen, Peter P. Müller, Ludger Grosse-Hovest
KEYWORDS:
Recombinant Antibody; Single Chain Diabody; Bispecific Antibody; Protein Expression
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.5,
May
30,
2013
ABSTRACT: Bispecific antibodies are
recombinant proteins with novel immunological properties and therapeutic potential.
Recombinant protein quality and activity of several bispecific antibodies
comprising different variable domain
combinations with respect to the parental monospecific single chain
fragments (scFv) were evaluated after expression in bacteria or mammalian
cells. The parental scFv proteins
humanized anti-NCAM scFv, murine
anti-VEGFR-2 scFv, murine and humanized anti-CD3 scFv, respectively, could successfully be expressed in E. coli, whereas the murine anti-NCAM
scFv version could not be reliably detected. Bispecific CD3 × VEGFR-2 and CD3 ×
NCAM anti-bodies were expressed in the bispecific single chain and the single
chain diabody format. However, the diabody derived from the murine anti-NCAM
scFv could not efficiently be expressed in E. coli or in mammalian cells.
Significant binding of the CD3 × NCAM
single chain diabody comprising the humanized version of anti-CD3 and
humanized version of anti-NCAM was efficient to both antigens. Nevertheless,
binding of the bispecific single chain version to the NCAM antigen was
inefficient in comparison to CD3 binding. In conclusion, the data could
indicate that the result of scFv expression in bacteria may be predictive for
the chances of success for functional expression of more complex bispecific
derivatives.