CD22 and acute lymphoblastic leukemia: Examples of ADCs in clinical practice include gemtuzumab ozogamicin (anti-CD33 mAb conjugated to calicheamicin antitumor antibiotic), which is used in pediatrics in combination therapy for CD33+ AML, Brentuximab vedotin (anti-CD30 antibody conjugated to an anti-mitotic small molecule) used in CD30+ lymphomas [8,9], and inotuzumab ozogamicin (anti-CD22 antibody conjugated to calicheamicin) for CD22+ ALL [10].