From Clone to Clinic pp 95-103 | Cite as
Biochemical and Immunological Evalution of an Anti-Fibrin Monoclonal Antibody Complex Containing T2G1s Fab’ Intended for Imaging Venous Thrombi
Abstract
The Fab’ fragment derived from a murine monoclonal antibody, T2G1s MAb, which is specific for an epitope on the β chain in fibrin II, was prepared, formulated, and labeled with Tc-99m for detection of thrombosis and thromboembolism. The MAb produced by cell cultivation is an IgGl. N-terminus sequence analysis revealed that the antibody consists of a mouse kappa light chain which is more homologous to subgroups II and V than others, and a heavy chain of subgroup III. Most Fab’ molecules have a reduced disulfide bond which links the light and heavy chains and they behave as intact Fab’ in solution as evidenced by HPLC size exclusion analysis. Competitive plate assay using human fibrin monomer showed that the T2G1s IgG and F(ab’)2 were about 7.2 fold more immunoreactive than the Fab’. At an optimal dose of 20 mCi per 0.5 mg Fab’, greater than 85% of the Tc-99m radiolabel could be incorporated into the Fab’. These analyses represent part of pre-clinical evaluation of a protein biopharmaceutical designed for imaging applications.
Keywords
Heavy Chain Stannous Chloride Absorptivity Coefficient Glucaric Acid Protein BiopharmaceuticalPreview
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