Single-domain antibodies (sdAbs) represent the minimal antigen binding-competent form of the immunoglobulin domain and have unique properties and applications. SdAbs are naturally produced as parts of the heavy-chain-only antibodies of camelid ruminants and cartilaginous fishes but can also be engineered synthetically from autonomous human or mouse VH or VL domains. The scope of this Research Topic covers current understanding and new developments in (i) the biology, immunology and immunogenetics of sdAbs in camelids and sharks, (ii) protein engineering approaches to increase the solubility, stability and antigen binding capacity of autonomous human VH/VL domains, and (iii) specialized applications, including diagnostics (taking advantage of sdAb robustness), imaging (taking advantage of sdAb small size) and therapeutics (taking advantage of sdAb targeting of ‘cryptic’ epitopes and modularity for incorporation into multispecific molecules). Original research articles, review articles or historical perspectives are all acceptable.

Keywords: Antibody, single-domain antibody, imaging, diagnostic, therapeutic

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