Balancing the extremes for antibody developability: hydrophobic and electrostatic germline framework signatures for CDR-loop compensation

Antibody therapeutics are a rapidly growing class of biopharmaceuticals, but concerns regarding potential developability issues persist. While complementarity-determining region (CDR) loops are imperative for antigen specificity and mutations are challenging, the framework regions can be exchanged to align with developability attributes such as aggregation, clearance, and viscosity, all governed by physicochemical characteristics. In this study, we systematically analyze the electrostatic and hydrophobic surface properties of germline-encoded antibody frameworks to assess their role in modulating Fv developability. Using structure prediction and surface patch analysis, we identify differences between kappa and lambda light-chain frameworks, characterize outlier germlines with extreme surface properties, and demonstrate using hydrophobic interaction chromatography and a heparin column that framework selection can compensate for CDR loop physicochemical characteristics. Our findings reveal that rational framework selection can serve as a systematic tool for optimizing antibody developability. This study provides a toolbox for antibody design, enhancing therapeutic candidate selection by leveraging inherent germline properties.