Abstract: Transthyretin amyloidosis is characterized by progressive deposition of the plasma protein transthyretin in the myocardium, peripheral nerves and/or other tissues, which can ultimately lead to congestive heart failure, polyneuropathy and death. The present invention provides binding proteins that can specifically bind to an isoaspartate residue in a transthyretin protein as well as their therapeutic, diagnostic and prognostic uses.