Template-Assisted Antibody Assembly: A Versatile Approach for Engineering Functional Antibody Nanoparticles

The clinical success of monoclonal antibody therapy has inspired research in understanding the fundamental molecular basis of antibody-antigen interactions and the engineering of antibodies and antibody assemblies with enhanced or novel properties. In particular, colloidally stable antibody assemblies can enhance dosing strategies and enable combined therapy of a mixture of antibodies or biologics. Herein, nanoassemblies of therapeutic antibodies were fabricated with controlled physicochemical properties using a versatile template-mediated assembly method. The antibody nanoparticles (AbNPs) cross-linked with poly(ethylene glycol)-N-hydroxysuccinimide were monodispersed, with particle diameters consistent with the template size (250 nm). When assembled using Herceptin or Kadcyla as a model antibody and antibody-drug conjugate, respectively, the nanoparticles retained the selectivity of the monoclonal antibody and recognized >98% of cells expressing the target receptors on cell membranes. Unlike the free Herceptin antibody, which was predominantly localized at the surface, the AbNPs were internalized via receptor-mediated endocytosis, presenting opportunities for delivering monoclonal antibodies intracellularly at high concentrations and/or against intracellular targets. With the vast array of antibodies that could be applied and different cross-linking chemistries possible, the reported antibody assembly strategy provides a versatile platform for the development of antibody assemblies for therapeutic, diagnostic, and clinical applications.