ABSTRACT

As biologics have become a mainstay in the development of novel therapies, protein engineering tools to expand on their structural advantages, namely specificity, affinity, and valency are of interest. Antibodies have dominated this field as the preferred scaffold for biologics development while there has been limited exploration into the use of albumin with its unique physiological characteristics as a platform for biologics design. There has been a great deal of interest to create bispecific and more complex multivalent molecules to build on the advantages offered by protein-based therapeutics relative to small molecules. Here, we explore the use of human serum albumin (HSA) as a scaffold for the design of multispecific biologics. In particular, we describe a structure-guided approach to the design of split HSA molecules we refer to as AlbuCORE, that effectively and spontaneously forms a native albumin-like molecule, but in a heterodimeric state upon co-expression. We show that the split AlbuCORE designs allow the creation of novel fusion entities with unique alternate geometries. We also show that, apart from these AlbuCORE fusion entities, there is an opportunity to explore their albumin-like small hydrophobic molecule carrying capacity as a drug conjugate in these designs.

摘要

随着生物制剂已成为新型疗法发展的主要手段，蛋白质工程工具将扩展其结构优势，即特异性，亲和力和效价，已引起人们的关注。在该领域，抗体已成为生物制剂开发的首选支架，而对于白蛋白及其独特的生理特性作为生物制剂设计平台的应用的探索还很有限。建立双特异性和更复杂的多价分子以建立在基于蛋白质的治疗剂相对于小分子的优势上引起了极大的兴趣。在这里，我们探索使用人类血清白蛋白（HSA）作为支架来设计多特异性生物制剂。特别是，我们描述了一种结构指导的方法来设计被称为AlbuCORE的分裂HSA分子，它可以有效地自发形成天然的白蛋白样分子，但在共表达时呈异二聚体状态。我们证明了分裂的AlbuCORE设计可以创建具有独特替代几何形状的新颖融合实体。我们还显示，除了这些AlbuCORE融合实体以外，还有机会探索这些设计中它们作为药物偶联物的白蛋白样小疏水分子的承载能力。