A Resource of High-Quality Nanobodies for Drug Delivery

Therapeutic and diagnostic efficacies of numerous small biomolecules and chemical compounds are hampered by poor pharmacokinetics. Here we developed a repertoire of distinct and high-affinity albumin-nanobodies (NbHSA) to facilitate drug delivery. Using biophysics and hybrid structural methods, we have systematically characterized the Nb repertoire, mapped the epitopes, and resolved the architecture of a tetrameric Nb-albumin complex. We employed quantitative proteomics for accurate and multiplex pharmacokinetic analysis of dozens of diverse and high-quality NbHSA and confirmed the most stable construct has a 771-fold T1/2 improvement compared to non-albumin binding Nbs. Interestingly, the pharmacokinetics of NbHSA is related to their biophysical and structural properties. To demonstrate the utility of NbHSA, we developed stable NbHSA-cytokine conjugates “Duraleukins” and confirmed the high anticancer efficacy of a Duraluekin in vivo. This high-quality Nb resource may help advance research into novel biotherapeutics.