Antigen-targeting strategies using single-domain antibody fragments

Abstract

Antibodies display high selectivity and affinity and have been the preferred platform for antigen targeting. Despite the development of antigen-delivery systems that enable T cell activation, targeting approaches that enhance antibody responses need improvement. This need specially applies to poorly antigenic compounds that facilitate pathogen and tumor cells to evade the immune system. Single-domain antibody fragments (VHHs) have been used extensively as neutralizing antibodies in the manner of conventional antibodies, but not yet as an antigen delivery system. The present collection of works investigated whether targeting broadly distinct antigen-presenting cell (APC) populations using VHHs could be used as an antigen-delivery platform to trigger immune responses, deliver drugs to specific cells, and to label cell in vivo for imaging and diagnostics.