title: Engaging the lysosomal compartment to combat B cell malignancies.
abstract: The combination of rituximab, a type I anti-CD20 mAb, with conventional chemotherapy has significantly improved the outcome of patients with B cell malignancies. Regardless of this success, many patients still relapse with therapy-resistant disease, highlighting the need for the development of mAbs with higher capacity to induce programmed cell death. The so-called type II anti-CD20 mAbs (e.g., tositumomab) that trigger caspase-independent B cell lymphoma cell death in vitro and show superior efficacy as compared with rituximab in eradicating target cells in mouse models are emerging as the next generation of therapeutic anti-CD20 mAbs. In this issue of the JCI, Ivanov and colleagues identify the lysosomal compartment as a target for type II mAbs (see the related article beginning on page 2143). These data encourage the further clinical development of type II mAbs as well as other lysosome-targeting drugs in the treatment of B cell malignancies.
authors.affiliation: Department of Hematology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Grønbaek
authors.forename: Marja
authors.initials: M
authors.lastname: Jäättelä
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20 / Q000502:physiology*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D006684:HLA-DR Antigens / Q000502:physiology*; D006801:Humans; D016393:Lymphoma, B-Cell / Q000188:drug therapy* / Q000473:pathology; D008247:Lysosomes / Q000187:drug effects* / Q000502:physiology; D000069283:Rituximab
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D018951:Antigens, CD20; D000970:Antineoplastic Agents; D006684:HLA-DR Antigens; D000069283:Rituximab