Improvement of single domain antibody stability by disulfide bond introduction.

The successful medical application of single domain antibodies largely depends on their functionality. This feature is partly determined by the intrinsic stability of the single domain. Therefore a lot of research has gone into the elucidation of rules to uniformly increase stability of antibodies. Recently, a novel intra-domain disulfide bond was independently discovered by two research groups, after either rational design or careful investigation of the naturally occurring camelid antibody repertoire. By introducing this particular disulfide bond within a single domain antibody, the conformational stability can be increased in general. In this chapter it is described how to introduce this extra intra-domain disulfide bond and how to estimate the biophysical and biochemical impact of this cystine on the domain.