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Biology subjects

Gaiduk, S.

Publications and source records attributed to Gaiduk, S..

2 recordsLinked to original sources

Structure-based design of antibody repertoires with drug-like properties

Animal immunization is the prevalent strategy for discovering antibody therapeutics1, but it is a lengthy and poorly controlled process. As an alternative, synthetic antibody repertoires deliver antibodies without animal welfare concerns, but the resulting antibodies often fail to exhibit "drug-like" biophysical properties1,2. Modern repertoires have improved developability by using a handful of frameworks with desirable biophysical properties, but at the cost of reduced structural diversity3-6. We developed a principled structure- and energy-based strategy, called CADAbRe, to navigate the complex tradeoffs between developability and structural diversity in repertoire design. The designed repertoire comprises billions of antibodies that are predicted to be stable and foldable, built from hundreds of different frameworks and hundreds of thousands of designed CDR H3s. We also developed an economical and scalable strategy for synthesizing large antibody repertoires, and as a proof of concept, designed and synthesized a 500-million variant phage display repertoire. Selections against four unrelated targets produced structurally diverse binders that exhibited drug-like properties, two of which were readily formatted as bispecifics for functional studies. Furthermore, one of the binders targets a challenging, highly charged surface. The proof-of-concept repertoire is available for academic research. We envision that the CADAbRe approach and repertoire will accelerate and rationalize antibody discovery while addressing animal-welfare concerns7.

synthetic biology↗

Energy-guided combinatorial co-optimization of antibody affinity and stability

Affinity maturation is an essential process in antibody engineering. Although powerful, it is iterative, time-consuming, and can result in trade-offs, where affinity is gained at the cost of important properties, such as specificity and stability. We present a scalable strategy, called LAffAb, that starts from a crystallographic structure of the antibody-antigen complex and introduces combinations of mutations to optimize its energy. A combinatorial library comprising 7,000 variants with up to nine mutations results in gains of up to 30-fold in affinity while co-optimizing stability. Surprisingly, the library does not converge on a single solution, instead favoring diverse variants with a high mutational load. Small-scale screening of 10 designs against a potential drug target results in an order-of-magnitude improvement in affinity while maintaining high developability. We also apply LAffAb to improve the developability of a therapeutic antibody without degrading affinity. We envision that LAffAb can be used to design stable, specific, and high-affinity binders and to improve our understanding of sequence, structure, and function relationships in antibodies.

synthetic biology↗