Figure 1.

Nanobodies are single-domain antibodies derived from llama heavy-chain-only antibodies. (A) Conventional antibodies from mammals are composed of two heavy- and two light chains, camelidae additionally express antibodies devoid of ligh chains, so called heavy-chain only antibodies. (B) Heavy-chain-only antibodies can bind to molecular crevices thereby blocking the active site of enzymes. (C) Nanobodies derived from heavy-chain-only antibodies can be engineered as dimers, half-life-extended heterotrimers containing an anti-albumin nanobody or as dimeric Fc-fusionprotein. (D) Anti-inflammatory nanobodies are currently evaluated in clinical trials.