A monoclonal antibody targeted nanoscale drug delivery system (NDDS) for chemotherapy was evaluated in CD20-positive Raji cells in vitro. Nanoparticles were formed by the assembly of an amphiphilic polymer consisting of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxypolyethyleneglycol-2000 (DSPE-PEG2000). Active carbon nanoparticles (ACNP) were conjugated to the chemotherapeutic agent...

We report the first preclinical in vitro and in vivo comparison of GA101 (obinutuzumab), a novel glycoengineered type II CD20 monoclonal antibody, with rituximab and ofatumumab, the two currently approved type I CD20 antibodies. The three antibodies were compared in assays measuring direct cell death (AnnexinV/PI staining and time-lapse microscopy), complement-dependent cytotoxicity (CDC), anti...

B-cell lymphomas continue to occur with a high incidence. The chimeric antibody known as Rituximab (Rituxan) has become a vital therapy for these patients. Rituximab induces cell death via binding and clustering of the CD20 receptor by Fcγ expressing effector cells. Because of the limited mobility of effector cells, it may be advantageous to cluster CD20 directly using multivalent nanostructure...

Change of CD20 expression was examined in cases of diffuse large B-cell lymphoma (DLBCL). CD20 expression after treatment with anti-CD20 antibody (rituximab, Rx) for DLBCL was examined in 23 cases who received serial biopsy by immunohistochemistry (IHC) and flow cytometry (FCM). CD20- by IHC and/or FCM was defined as CD20-. Four cases were CD20- at initial biopsy but became CD20+ after chemothe...

Multivalent antibodies, either monospecific or bispecific, may improve the efficacy of current therapeutic interventions involving a single monoclonal antibody (mAb). We have applied the Dock-and-Lock (DNL) method, a new platform technology for the site-specific and covalent assembly of modular components into stably tethered complexes of defined composition, to prepare a hexavalent, anti-CD20 ...

BACKGROUND Incorporation of the chimeric CD20 monoclonal antibody rituximab in the treatment schedule of patients with non-Hodgkin's lymphoma has significantly improved outcome. Despite this success, about half of the patients do not respond to treatment or suffer from a relapse and additional therapy is required. A low CD20-expression level may in part be responsible for resistance against rit...

Clinical administration of the anti-CD20 antibody IDEC-C2B8 can induce remission of low-grade B-cell lymphoma. Whereas it has been suggested that the main mechanisms of action are complement-mediated and antibody-dependent cell-mediated cytotoxicity, we demonstrate that monoclonal antibody IDEC-C2B8 is a strong inducer of apoptosis in CD20-positive B-cell lymphoma cell lines reflecting differen...

Chemotherapy combinations with monoclonal antibodies are now the basis for treatment of chronic lymphocytic leukemia. Rituximab, the most widely used anti-CD20 antibody in routine clinical practice, led not only to improvement of progression-free survival, but also to improvement of overall survival in previously untreated patients with good performance status in combination with fludarabine an...

Antibody-based therapies, both unconjugated antibodies and radioimmunotherapy, have had a significant impact on the treatment of non-Hodgkin lymphoma. Single-agent rituximab is an effective therapy, but it is being increasingly used with combination chemotherapy to improve the objective response and its duration. The approved anti-CD20 radioimmunoconjugates ((90)Y-ibritumomab tiuxetan or (131)I...

The antibody-dependent cellular cytotoxicity (ADCC) of natural killer (NK) cells is assumed to contribute to the clinical efficacy of monoclonal antibodies (mAbs) in chronic lymphocytic leukemia (CLL) and other hematopoietic malignancies of B cell origin. We sought to determine whether reactive oxygen species (ROS)-producing monocytes regulate the ADCC of NK cells against primary CLL cells usin...