Nanobodies (aka single domain antibodies or VHH antibodies) are a type of antibodies derived from camelids, and are much smaller than traditional antibodies. Standard antibodies are giants by molecular standards, since each one is a conglomerate of two heavy protein chains and two light chains, intricately folded and garnished with elaborate sugars. Nanobodies, however, are relatively simple proteins about a tenth the size of human antibodies and just a few nanometers in length. After the discovery that camelidae (camels and llamas) possess fully functional antibodies that lack light chains, the nanobody technology was developed to exploit these smaller heavy-chain-only constructs. Nanobodies are being researched for multiple pharmaceutical applications and have potential for use in cancer and Alzheimer's Disease treatments.

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