Single-domain antibodies

The antigen-binding entity of an antibody, reduced in size to one single domain, is referred to as a "single-domain antibody". Various strategies have been explored with variable success to arrive at functional sinlge-domain antibodies. The potential of single-domain antibodies, as research tools or in medicine, is reflected by the three companies -founded in Europe- with a mission to bring these molecules to the market. Domantis using VH-derived single-domain antibodies started in 2000 and was bought by GSK for 300M Pound in December 2007. Haptogen employing shark single-domain antibodies was acquired by Wyeth, and ablynx focusing on llama-derived single-domain antibodies recieved over euro70M in three rounds of venture capitalist investments and another euro80M on the Euronext stock market in November 2007. Regarding therapeutic applications, Arana Therapeutics in Australia entered a Phase 2 clinical trial with its single-domain antibody derivative. In this chapter, we will review (1) the various antibodies used for generating single-domain antibodies, (2) the properties of single-domain antibodies that create an added value for use in immunotherapy, and (3) a number of therapeutic applications.

Publication year:2009

Keywords:single-domain antibodies, immunotherapy, therapeutic applications