A novel heterobifunctional linker for formyl to thiol coupling

Area of Science:

• Bioconjugation Chemistry
• Immunology
• Oncology

Background:

• Development of targeted cancer therapies requires efficient methods for linking drugs to targeting moieties.
• Monoclonal antibodies offer high specificity for tumor antigens but require effective conjugation strategies for drug delivery.

Purpose of the Study:

• To synthesize and evaluate a novel heterobifunctional cross-linking agent for antibody-drug conjugate (ADC) development.
• To conjugate an antineoplastic agent (ellipticine) to polyaldehyde dextran and subsequently link it to a monoclonal antibody (17-1A) or its fragment (Fab').

Main Methods:

• Synthesis of a maleimide hydrazide heterobifunctional cross-linker.
• Coupling of ellipticine-attached polyaldehyde dextran to the 17-1A monoclonal antibody or its Fab' fragment using the synthesized linker.
• Assessment of binding avidity of the resulting drug-dextran-linker-antibody conjugates to SW1116 colorectal tumor cells.

Main Results:

• Successful synthesis of the maleimide hydrazide cross-linking agent.
• Effective conjugation of the drug-dextran complex to the antibody, forming stable drug-dextran-linker-antibody conjugates.
• The conjugates demonstrated high binding avidity for the target antigen on SW1116 colorectal tumor cells, indicating retained biological activity.

Conclusions:

• The novel maleimide hydrazide linker is effective for creating antibody-drug conjugates via thiol-formyl coupling.
• The developed drug-dextran-linker-antibody conjugates maintain high antigen-binding avidity, showing promise for targeted colorectal cancer therapy.