BACKGROUND The sensitivity of human Burkitt's lymphoma cells to rituximab (Rtx) and tositumomab (Tst) was assessed on cells expressing different levels of CD20 on surface. Cells that harbor low CD20 levels may resists against therapeutics response to CD20-specific antibodies. We postulated that, radiation-induced modulation of CD20 surface levels may play a crucial and central role in determini...

The anti-CD20 antibody rituximab is useful in the treatment of certain B-cell malignancies, most notably non-Hodgkin's lymphoma. Its efficacy has been increased when used in combination with chemotherapy, yet anti-CD20 monoclonal antibodies (mAbs) directly conjugated with drugs such as doxorubicin (Dox) have failed to deliver drug or to demonstrate antitumor activity. We have produced anti-CD20...

Combination immunotherapy with anti-CD20 and anti-CD22 mAbs shows promising activity in non-Hodgkin lymphoma. Therefore, bispecific mAbs (bsAbs) were recombinantly constructed from veltuzumab (humanized anti-CD20) and epratuzumab (humanized anti-CD22) and evaluated in vitro and in vivo. While none of the parental mAbs alone or mixed had notable antiproliferative activity against Burkitt lymphom...

Anti-CD20 antibody immunotherapy effectively treats non-Hodgkin's lymphoma and autoimmune disease. However, the cellular and molecular pathways for B cell depletion remain undefined because human mechanistic studies are limited. Proposed mechanisms include antibody-, effector cell-, and complement-dependent cytotoxicity, the disruption of CD20 signaling pathways, and the induction of apoptosis....

Abstract Complement dependent cytotoxicity (CDC) is a key Fc mediated function of monoclonal antibody (mAb) therapeutics. mAb binding to antigen triggers complex molecular cascade with sequential recruitment serum proteins, eventuating in target cell lysis. Here we demonstrate CDC quantification streamlined, vitro, advanced flow cytometry assay. Anti-CD20 mAbs were incubated lines 96- or 384-we...

Clinical trials revealed that systemic administration of B-cell-depleting anti-CD20 antibodies can hold lesion formation in the early relapsing-remitting phase of multiple sclerosis (MS). Throughout the secondary-progressive (SP) course of MS, pathogenic B cells may, however, progressively replicate within the central nervous system (CNS) itself, which is largely inaccessible to systemic anti-C...

CD20 is a nonglycosylated 33 to 37 kD phosphoprotein involved in B-cell signaling that subserves important functions in the regulation of B-cell proliferation and differentiation. In addition, this B-cell surface antigen has been shown recently to be an effective target for immunotherapy of B-cell malignancies using chimeric (mouse/human) or radiolabeled murine monoclonal anti-CD20 antibodies. ...

The anti-CD20 monoclonal antibody (mAb) rituximab has been used successfully for lymphoma therapy for more than 10 years. Although several direct mechanisms by which anti-CD20 mAbs act have been characterized in vitro, their specific role in clinical efficacy is still debated. Little is known about the possible antitumor immune response that they may induce in patients, despite clinical data su...

The anti-CD20 monoclonal antibody (mAb) rituximab has revolutionized the treatment of B-cell malignancies. This unprecedented success has not only substantially changed the mindset of the clinical community about the ability of mAb to improve outcomes but has catalyzed the interest in the pharmaceutical industry to develop the next generation of anti-CD20 mAbs. Since the introduction of rituxim...