FIGURE 1.

Structural features of classical and camelid heavy‐chain antibodies. (A) In a conventional IgG, pairing of a variable heavy and variable light chains are required to assemble the paratope, while in camelid heavy‐chain antibody the V_HH domain does not require a light chain to bind the antigen. Inset: The secondary structure of heavy‐chain‐only antibodies showing three hypervariable loop regions known as the loop H1, H2, and H3. (B) comparison of the antigen‐binding surfaces of conventional IgG (left) and heavy‐chain‐only antibody (right). Adapted from Mitchel et al ²⁶