Rabbit Anti-VHH Antibody

VHH antibodies, also known as nanobodies, are the variable domains of the heavy-chain-only antibodies naturally found in camelids (such as camels and llamas), and they are the smallest known intact antigen-binding fragments. Unlike conventional antibodies, in which the heavy and light chains together form the antigen-binding site, a VHH consists of a single domain with a molecular weight of only about 12 to 15 kDa. This single-domain structure gives it unique advantages: its framework region has undergone hydrophilic amino acid substitutions (such as Gly44Glu and Leu45Arg), which compensate for the exposed hydrophobic interface caused by the missing light chain, thereby conferring extremely high solubility and stability and enabling it to withstand extreme temperatures and acidic environments. At the same time, VHHs possess a longer CDR3 loop that often forms a protruding conformation, allowing them to penetrate recessed epitopes that are difficult for conventional antibodies to reach, such as enzyme active sites or viral capsid canyons, while still achieving antigen-binding affinities in the nanomolar to picomolar range.