Recently, Tector et al. (26) showed that CTLA-4–positive plasma of patients with myasthenia gravis after purification and enrichment by an N terminus CTLA-4 mAb column specifically bound anti–CTLA-4 Abs and the CTLA-4 ligand CD80/CD86 fusion proteins. The gene discussed is CTLA4; the disease is myasthenia gravis.