Here, we report on a novel bispecific antibody-derivative, designated RTX-CD47, with unique capacity for CD20-directed inhibition of CD47-SIRPα "don't eat me" signaling. RTX-CD47 comprises a CD20-targeting scFv antibody fragment derived from rituximab fused in tandem to a CD47-blocking scFv. Single agent treatment with RTX-CD47 triggered significant phagocytic removal of CD20pos/CD47pos maligna...

The aim of adoptive T-cell therapy of cancer is to selectively confer immunity against tumor cells. Autoimmune side effects, however, remain a risk, emphasizing the relevance of a suicide mechanism allowing in vivo elimination of infused T cells. We investigated the use of human CD20 as suicide gene in T-lymphocytes. Potential effects of forced CD20 expression on T-cell function were investigat...

Immune-mediated, acquired pure red cell aplasia (PRCA) is a rare disorder frequently associated with other autoimmune phenomena. Conventional immunosuppressive treatment is often unsatisfactory. Rituximab is a monoclonal antibody against the CD20 antigen, highly effective for in vivo B-cell depletion. An 18-month-old girl with both severe PRCA and autoimmune hemolytic anemia, refractory to immu...

Lenalidomide, an immunomodulatory agent that enhances antibody-dependent cellular cytotoxicity (ADCC), is currently being investigated as a therapy for chronic lymphocytic leukemia (CLL). The anti-CD20 antibody rituximab is active in CLL and represents a rational agent to combine with lenalidomide. We therefore examined whether lenalidomide combined with rituximab enhances direct apoptosis and ...

We read with interest the paper from Jilani et al 1 in which rituximab treatment appeared to down-modulate CD20 expression through a combination of internalization and RNA regulation. The result is unexpected because previous studies had shown that CD20 is not modulated by monoclonal antibody (mAb) treatment, 2-4 even in vivo. 5 The study by Jilani et al used an anti–mouse immunoglobu-lin polyc...

Targeting the surface of malignant cells has evolved into a cornerstone in cancer therapy, paradigmatically introduced by the success of humoral immunotherapy against CD20 in malignant lymphoma. However, tumor cell susceptibility to immunochemotherapy varies, with mostly a fatal outcome in cases of resistant disease. Here, we show that lymphoma exosomes shield target cells from antibody attack ...

R ituximab is a chimeric monoclonal antibody that was developed for the treatment of B cell lymphomas. It is directed against the CD20 cell surface molecule. CD20 is a tetraspan membrane protein that is present only on B cells, and is expressed initially at the immature B cell stage, remaining until the final differentiation into plasma cells. The function of CD20 is not clear, although it may ...

The clinical efficacy of the CD20-specific chimeric monoclonal antibody rituximab is significantly hampered by intrinsic or acquired resistance to therapy. Rituximab activates antibody-dependent cellular cytotoxicity/complement-dependent cytotoxicity-dependent lysis but also induces apoptosis by cross-linking of its target antigen CD20. Recent reports indicate that this apoptotic activity of ri...

Chronic graft-versus-host disease (cGVHD) is an important determinant of long-term morbidity and mortality in allogeneic stem cell transplantation patients. Because cGVHD has clinical, histologic, and laboratory findings of autoimmune diseases and anti-B-cell therapy has shown efficacy in autoimmune diseases, we hypothesized that monoclonal anti-CD20 antibody therapy might improve patients with...

OBJECTIVE The mechanism of action of anti-B cell therapy in multiple sclerosis (MS) is not fully understood. Here, we compared the effect of anti-CD20 therapy on microglial activation in two distinct focal rat models of MS. METHODS The effect of anti-CD20 therapy on lesion formation and extralesional microglial activation was evaluated in the fDTH-EAE (experimental allergic encephalomyelitis)...