Bioengineering and computational analysis of programmed cell death ligand-1 monoclonal antibody

Area of Science:

• Immunology and Biotechnology
• Protein Engineering and Structural Biology

Background:

• Programmed cell death ligand-1 (PD-L1) and programmed death-1 (PD-1) are key regulators of immune responses and self-tolerance.
• Therapeutic antibodies targeting PD-1/PD-L1 interactions are crucial for promoting T-cell proliferation and enhancing anti-tumor immunity.

Purpose of the Study:

• To construct recombinant molecules for producing potent antibodies against PD-L1.
• To optimize the expression and purification of full-length antibodies from mammalian cell lines.
• To characterize the binding affinity and structural properties of the generated antibodies.

Main Methods:

• Cloning of PD-L1 variable regions into pMH3 vectors for expression in mammalian cells.
• G418 screening and serum-free culture for recombinant clone selection and maintenance.
• ELISA, immunofluorescence, and protein-protein interaction (PPI) docking for antibody characterization.
• Homology modeling using SWISS model and 3D structure validation with ZDOCK, Chimera, and PyMOL.

Main Results:

• Successfully constructed and expressed recombinant PD-L1 antibodies in mammalian cell lines.
• Isolated and purified full-length antibodies at concentrations of 0.5-0.8 mg/ml.
• Validated high-quality antibody structures (>90% Ramachandran plot values) and confirmed antigen-antibody interactions.

Conclusions:

• Recombinant technology provides an effective platform for producing high-affinity antibodies targeting PD-L1.
• The developed methods ensure accurate determination of antigen-antibody interactions for therapeutic antibody development.
• This approach holds promise for advancing cancer immunotherapy by generating novel PD-1/PD-L1 blocking agents.