Engineering pH-Sensitive Single-Domain Antibodies

Area of Science:

• Biotechnology
• Immunology
• Protein Engineering

Background:

• Antibody engineering seeks to enhance functionality beyond affinity and specificity.
• pH-dependent control of antibody binding is a desirable feature for regulated molecular interactions.

Purpose of the Study:

• To provide a methodology for generating single-domain antibodies (sdAbs) with pH-dependent binding capabilities.
• To establish a framework for designing combinatorial histidine scanning libraries within sdAb-antigen interfaces.

Main Methods:

• Conceptual framework for combinatorial histidine scanning library design.
• Construction of a phage display library with up to 1 x 10^10 unique members.
• Phage display protocols for selection and analysis of pH-dependent sdAb clones.

Main Results:

• Successful generation of a methodology for pH-dependent sdAbs.
• Demonstration of histidine scanning for modulating binding characteristics.
• Establishment of protocols for isolating specific pH-dependent antibody variants.

Conclusions:

• The described methodology enables the creation of custom-regulated single-domain antibodies.
• Histidine scanning is an effective strategy for engineering pH-dependent antibody binding.
• This work provides tools for developing novel antibody-based therapeutics and diagnostics with conditional activity.