Objective

Cysteine-knot miniproteins (knottins) have potential as therapeutic agents to block ion channels and GPCRS involved in cancer, autoimmunity and pain but suffer from manufacturing difficulties, short half-lives and a lack of specificity. Using X-ray crystallography and biochemical assays we have demonstrated that functional knottins can be inserted into peripheral antibody CDRs via short linkers. This approach greatly increases the diversity of these peripheral CDR loops while allowing additional contribution of binding from the remaining CDRs. Thus, the resulting “KnotBody” retains the advantage of blocking activity from the knottin while enjoying the extended half-life and additional specificity conferred by the antibody molecule.  We have used this novel antibody format to develop a panel of low-nM Kv1.3 and ASIC1a inhibitors which could be developed as therapeutics for the treatment of autoimmune and neurological disorders.