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Sample records for rituximab chimeric anti-cd20

  1. Real Time Analysis of Binding between Rituximab (anti-CD20 antibody) and B Lymphoma Cells

    PubMed Central

    Tan, Liang; Lin, Peiling; Chisti, Mohammad M.; Rehman, Abdul; Zeng, Xiangqun

    2013-01-01

    CD20, expressed on greater than 90% of B-lymphocytic lymphomas, is an attractive target for antibody therapy. Rituximab is a chimeric murine/human-engineered monoclonal antibody and can selectively deplete CD20-expressing cells in peripheral blood and lymphoid tissues. The immobilization of B-lymphoblast-like Burkitt's lymphoma Raji cells on the quartz crystal microbalance (QCM) gold electrode surface using RGD tripeptide was electrochemically confirmed. The real-time processes of attachment of Raji cells on the gold electrode and the subsequent binding of Rituximab to the cells were studied using QCM biosensor. The interaction between Rituximab and Raji cells led to the increased resonant frequency shifts (Δf0) in the studied antibody concentration range from 5 to 250 µg mL−1 following the Langmuir adsorption model. From these observations, the apparent binding constant between a single-layer of Rituximab and Raji cells was calculated to be 1.6×106 M−1. Control experiments using other therapeutic antibodies (i.e., Trastuzumab and Bevacizumab) and different cells (i.e., T cells and endothelial cells) proved the specific interaction between Rituximab and B cells. The effects of Ca2+ and Mn2+ ions on the Rituximab-Raji cell interaction were also studied providing the enhanced QCM signals, in particular, further indicating that CD20 is a calcium ion channel that can transport these metal ions into the cells and accelerate the cell lysis induced by Rituximab. Thus the real time capability of QCM and its simplicity of operation are highly suitable for multipurpose studies on living cells including cell-immobilization, cytotoxicity of drugs, and the cell action mechanisms. PMID:23926879

  2. Suppression of Rituximab-resistant B-cell lymphoma with a novel multi-component anti-CD20 mAb nanocluster

    PubMed Central

    Zhao, He; Sun, Yun; Zhao, Mengxin; Chen, Di; Zhu, Xiandi; Zhang, Li; Li, Bohua; Dai, Jianxin; Li, Wei

    2015-01-01

    Although the anti-CD20 antibody Rituximab has revolutionized the treatment of Non-Hodgkin Lymphoma (NHL), resistance to treatment still existed. Thus, strategies for suppressing Rituximab-resistant NHLs are urgently needed. Here, an anti-CD20 nanocluster (ACNC) is successfully constructed from its type I and type II mAb (Rituximab and 11B8). These distinct anti-CD20 mAbs are mass grafted to a short chain polymer (polyethylenimine). Compared with parental Rituximab and 11B8, the ACNC had a reduced “off-rate”. Importantly, ACNC efficiently inhibited Rituximab-resistant lymphomas in both disseminated and localized human NHL xenograft models. Further results revealed that ACNC is significantly potent in inducing caspase-dependent apoptosis and lysosome-mediated programmed cell death (PCD). This may help explain why ACNC is effective in suppressing rituximab-resistant lymphoma while Rituximab and 11B8 are not. Additionally, ACNC experienced low clearance from peripheral blood and high intratumor accumulation. This improved pharmacokinetics is attributed to the antibody-antigen reaction (active targeting) and enhanced permeability and retention (ERP) effect (passive targeting). This study suggested that ACNC might be a promising therapeutic agent for treatment of rituximab-resistant lymphomas. PMID:26284588

  3. The anti-CD20 monoclonal antibody rituximab to treat acquired haemophilia A

    PubMed Central

    D’Arena, Giovanni; Grandone, Elvira; Di Minno, Matteo N.D.; Musto, Pellegrino; Di Minno, Giovanni

    2016-01-01

    Background Acquired haemophilia A (AHA) is a rare bleeding disorder caused by the development of specific autoantibodies against naturally occurring factor VIII (FVIII). Although about half of cases are idiopathic, AHA may be associated with several non-neoplastic conditions, autoimmune disorders, as well as haematological malignancies, such as chronic lymphocytic leukaemia and lymphoma. The long-term suppression of inhibitors is one of the mainstays of the treatment of AHA. Apart from standard immunosuppressive treatments, rituximab has been proven to be effective in AHA. Materials and methods The aim of this review is to provide a systematic description of data available in the literature on this topic. To do so, we performed a search using the indexed online database Medline/PubMed, without temporal limits, matching the words “rituximab” and “acquired h(a)emophilia”. Furthermore, additional published studies were identified in the reference list of the publications found in PubMed. Results The review of the literature confirms that rituximab may be a safe and useful treatment for AHA. Discussion Although rituximab is not a standard therapy for AHA, it may be useful in resistant cases. However, the definitive place of this monoclonal antibody in the therapeutic strategy for AHA (first or second-line, alone or in combination with other drugs) remains to be determined more precisely and warrants further investigation. PMID:26509821

  4. Phase I study of chimeric anti-CD20 monoclonal antibody in Chinese patients with CD20-positive non-Hodgkin's lymphoma

    PubMed Central

    Gui, Lin; Han, Xiaohong; He, Xiaohui; Song, Yuanyuan; Yao, Jiarui; Yang, Jianliang; Liu, Peng; Qin, Yan; Zhang, Shuxiang; Zhang, Weijing; Gai, Wenlin; Xie, Liangzhi

    2016-01-01

    Objective: This study was designed to determine the safety, pharmacokinetics and biologic effects of a human-mouse chimeric anti-CD20 monoclonal antibody (SCT400) in Chinese patients with CD20-positive B-cell non-Hodgkin's lymphoma (CD20+ B-cell NHL). SCT400 has an identical amino acid sequence as rituximab, with the exception of one amino acid in the CH1 domain of the heavy chain, which is common in Asians. Methods: Fifteen patients with CD20+ B-cell NHL received dose-escalating SCT400 infusions (250 mg/m2: n=3; 375 mg/m2: n=9; 500 mg/m2: n=3) once weekly for 4 consecutive weeks with a 24-week follow-up period. The data of all patients were collected for pharmacokinetics and pharmacodynamics analyses. Results: No dose-limiting toxicities were observed. Most drug-related adverse events were grade 1 or 2. Two patients had grade 3 or 4 neutropenia. Under premedication, the drug-related infusion reaction was mild. A rapid, profound and durable depletion of circulating B cells was observed in all dose groups without significant effects on T cell count, natural killer (NK) cell count or immunoglobulin levels. No patient developed anti-SCT400 antibodies during the course of the study. SCT400 serum half-life (T1/2), maximum concentration (Cmax) and area under the curve (AUC) generally increased between the first and fourth infusions (P<0.05). At the 375 mg/m2 dose, the T1/2 was 122.5±46.7 h vs. 197.0±75.0 h, respectively, and the Cmax was 200.6±20.2 g/mL vs. 339.1±71.0 g/mL, respectively. From 250 mg/m2 to 500 mg/m2, the Cmax and AUC increased significantly in a dose-dependent manner (P<0.05). Patients with a high tumor burden had markedly lower serum SCT400 concentrations compared with those without or with a low tumor burden. Of the 9 assessable patients, 1 achieved complete response and 2 achieved partial responses. Conclusions: SCT400 is well-tolerated and has encouraging preliminary efficacy in Chinese patients with CD20+ B-cell NHL. PMID:27199517

  5. Comparability analysis of anti-CD20 commercial (rituximab) and RNAi-mediated fucosylated antibodies by two LC-MS approaches

    PubMed Central

    Li, Chen; Rossomando, Anthony; Wu, Shiaw-Lin; Karger, Barry L.

    2013-01-01

    In developing biosimilar or biobetter products, comparability to the reference product is required to claim similar integrity or intended purpose. In this work, an anti-CD20 monoclonal antibody developed using RNA interference to decrease core fucosylation (RNAi-mediated) was comprehensively characterized by LC-MS and compared with the commercially-available anti-CD20 rituximab (MabThera®). As anticipated, < 30% core fucose was found within the RNAi-produced molecule (compared with > 90% in rituximab), and the reduction in fucose resulting in a significant improvement in FcγRΙΙΙa binding and antibody-dependent cell-mediated cytotoxicity. Two mutations, S258Y (fully mutated) and F174I/L (partially mutated), however, were detected in the production of the RNAi-mediated molecule. An alternative LC-MS approach using dimethyl labeling (i.e., 2CH2 for rituximab and 2CD2 for the RNAi-mediated molecule) was developed to additionally compare the two mAbs and confirm the full sequence with the two mutation sites. Furthermore, disulfide linkages were found to be the same for the two antibodies, with a small portion of unpaired cysteines in both products. Disulfides were correctly linked if the samples were prepared at low pH (i.e., enzymatic digestion by pepsin at pH 2); however, trace amounts of scrambling were found by trypsin digestion at pH 6.8, and this scrambling increased significantly at pH 8. Typical modifications, such as pyro-Glu formation at the N-terminus, K clipping at the C-terminus, oxidation at Met, and deamidation at Asn, were also detected with no significant differences between the two products. Using the LC-MS approaches for the comparability study, product integrity with critical structure information was revealed for confirmation of intended purpose (core fucosylation), identification of critical parameters (e.g., sample pH), and correction as needed (amino acid mutation). PMID:23751726

  6. Production of an active anti-CD20-hIL-2 immunocytokine in Nicotiana benthamiana.

    PubMed

    Marusic, Carla; Novelli, Flavia; Salzano, Anna M; Scaloni, Andrea; Benvenuto, Eugenio; Pioli, Claudio; Donini, Marcello

    2016-01-01

    Anti-CD20 murine or chimeric antibodies (Abs) have been used to treat non-Hodgkin lymphomas (NHLs) and other diseases characterized by overactive or dysfunctional B cells. Anti-CD20 Abs demonstrated to be effective in inducing regression of B-cell lymphomas, although in many cases patients relapse following treatment. A promising approach to improve the outcome of mAb therapy is the use of anti-CD20 antibodies to deliver cytokines to the tumour microenvironment. In particular, IL-2-based immunocytokines have shown enhanced antitumour activity in several preclinical studies. Here, we report on the engineering of an anti-CD20-human interleukin-2 (hIL-2) immunocytokine (2B8-Fc-hIL2) based on the C2B8 mAb (Rituximab) and the resulting ectopic expression in Nicotiana benthamiana. The scFv-Fc-engineered immunocytokine is fully assembled in plants with minor degradation products as assessed by SDS-PAGE and gel filtration. Purification yields using protein-A affinity chromatography were in the range of 15-20 mg/kg of fresh leaf weight (FW). Glycopeptide analysis confirmed the presence of a highly homogeneous plant-type glycosylation. 2B8-Fc-hIL2 and the cognate 2B8-Fc antibody, devoid of hIL-2, were assayed by flow cytometry on Daudi cells revealing a CD20 binding activity comparable to that of Rituximab and were effective in eliciting antibody-dependent cell-mediated cytotoxicity of human PBMC versus Daudi cells, demonstrating their functional integrity. In 2B8-Fc-hIL2, IL-2 accessibility and biological activity were verified by flow cytometry and cell proliferation assay. To our knowledge, this is the first example of a recombinant immunocytokine based on the therapeutic Rituximab antibody scaffold, whose expression in plants may be a valuable tool for NHLs treatment. PMID:25879373

  7. Synergistic anti-tumor activity of acadesine (AICAR) in combination with the anti-CD20 monoclonal antibody rituximab in in vivo and in vitro models of mantle cell lymphoma

    PubMed Central

    Montraveta, Arnau; Xargay-Torrent, Sílvia; López-Guerra, Mónica; Rosich, Laia; Pérez-Galán, Patricia; Salaverria, Itziar; Beà, Silvia; Kalko, Susana G.; de Frias, Mercè; Campàs, Clara; Roué, Gaël; Colomer, Dolors

    2014-01-01

    Mantle cell lymphoma (MCL) is considered one of the most challenging lymphoma, with limited responses to current therapies. Acadesine, a nucleoside analogue has shown antitumoral effects in different preclinical cancer models as well as in a recent phase I/II clinical trial conducted in patients with chronic lymphocytic leukemia. Here we observed that acadesine exerted a selective antitumoral activity in the majority of MCL cell lines and primary MCL samples, independently of adverse cytogenetic factors. Moreover, acadesine was highly synergistic, both in vitro and in vivo, with the anti-CD20 monoclonal antibody rituximab, commonly used in combination therapy for MCL. Gene expression profiling analysis in harvested tumors suggested that acadesine modulates immune response, actin cytoskeleton organization and metal binding, pointing out a substantial impact on metabolic processes by the nucleoside analog. Rituximab also induced changes on metal binding and immune responses. The combination of both drugs enhanced the gene signature corresponding to each single agent, showing an enrichment of genes involved in inflammation, metabolic stress, apoptosis and proliferation. These effects could be important as aberrant apoptotic and proinflammatory pathways play a significant role in the pathogenesis of MCL. In summary, our results suggest that acadesine exerts a cytotoxic effect in MCL in combination with rituximab, by decreasing the proliferative and survival signatures of the disease, thus supporting the clinical examination of this strategy in MCL patients. PMID:24519895

  8. Serum BAFF and APRIL Levels, T-Lymphocyte Subsets, and Immunoglobulins after B-Cell Depletion Using the Monoclonal Anti-CD20 Antibody Rituximab in Myalgic Encephalopathy/Chronic Fatigue Syndrome.

    PubMed

    Lunde, Sigrid; Kristoffersen, Einar K; Sapkota, Dipak; Risa, Kristin; Dahl, Olav; Bruland, Ove; Mella, Olav; Fluge, Øystein

    2016-01-01

    Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We have previously suggested clinical benefit from B-cell depletion using the monoclonal anti-CD20 antibody rituximab in a randomized and placebo-controlled study. Prolonged responses were then demonstrated in an open-label phase-II study with maintenance rituximab treatment. Using blood samples from patients in the previous two clinical trials, we investigated quantitative changes in T-lymphocyte subsets, in immunoglobulins, and in serum levels of two B-cell regulating cytokines during follow-up. B-lymphocyte activating factor of the tumor necrosis family (BAFF) in baseline serum samples was elevated in 70 ME/CFS patients as compared to 56 healthy controls (p = 0.011). There were no significant differences in baseline serum BAFF levels between patients with mild, moderate, or severe ME/CFS, or between responders and non-responders to rituximab. A proliferation-inducing ligand (APRIL) serum levels were not significantly different in ME/CFS patients compared to healthy controls at baseline, and no changes in serum levels were seen during follow-up. Immunophenotyping of peripheral blood T-lymphocyte subsets and T-cell activation markers at multiple time points during follow-up showed no significant differences over time, between rituximab and placebo groups, or between responders and non-responders to rituximab. Baseline serum IgG levels were significantly lower in patients with subsequent response after rituximab therapy compared to non-responders (p = 0.03). In the maintenance study, slight but significant reductions in mean serum immunoglobulin levels were observed at 24 months compared to baseline; IgG 10.6-9.5 g/L, IgA 1.8-1.5 g/L, and IgM 0.97-0.70 g/L. Although no functional assays were performed, the lack of significant associations of T- and NK-cell subset numbers with B-cell depletion, as well as the lack of associations to clinical responses, suggest that B

  9. Serum BAFF and APRIL Levels, T-Lymphocyte Subsets, and Immunoglobulins after B-Cell Depletion Using the Monoclonal Anti-CD20 Antibody Rituximab in Myalgic Encephalopathy/Chronic Fatigue Syndrome

    PubMed Central

    Lunde, Sigrid; Kristoffersen, Einar K.; Sapkota, Dipak; Risa, Kristin; Dahl, Olav; Bruland, Ove; Mella, Olav; Fluge, Øystein

    2016-01-01

    Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We have previously suggested clinical benefit from B-cell depletion using the monoclonal anti-CD20 antibody rituximab in a randomized and placebo-controlled study. Prolonged responses were then demonstrated in an open-label phase-II study with maintenance rituximab treatment. Using blood samples from patients in the previous two clinical trials, we investigated quantitative changes in T-lymphocyte subsets, in immunoglobulins, and in serum levels of two B-cell regulating cytokines during follow-up. B-lymphocyte activating factor of the tumor necrosis family (BAFF) in baseline serum samples was elevated in 70 ME/CFS patients as compared to 56 healthy controls (p = 0.011). There were no significant differences in baseline serum BAFF levels between patients with mild, moderate, or severe ME/CFS, or between responders and non-responders to rituximab. A proliferation-inducing ligand (APRIL) serum levels were not significantly different in ME/CFS patients compared to healthy controls at baseline, and no changes in serum levels were seen during follow-up. Immunophenotyping of peripheral blood T-lymphocyte subsets and T-cell activation markers at multiple time points during follow-up showed no significant differences over time, between rituximab and placebo groups, or between responders and non-responders to rituximab. Baseline serum IgG levels were significantly lower in patients with subsequent response after rituximab therapy compared to non-responders (p = 0.03). In the maintenance study, slight but significant reductions in mean serum immunoglobulin levels were observed at 24 months compared to baseline; IgG 10.6–9.5 g/L, IgA 1.8–1.5 g/L, and IgM 0.97–0.70 g/L. Although no functional assays were performed, the lack of significant associations of T- and NK-cell subset numbers with B-cell depletion, as well as the lack of associations to clinical responses, suggest that B

  10. Characterization of anti-CD20 monoclonal antibody produced by transgenic silkworms (Bombyx mori)

    PubMed Central

    Tada, Minoru; Tatematsu, Ken-Ichiro; Ishii-Watabe, Akiko; Harazono, Akira; Takakura, Daisuke; Hashii, Noritaka; Sezutsu, Hideki; Kawasaki, Nana

    2015-01-01

    In response to the successful use of monoclonal antibodies (mAbs) in the treatment of various diseases, systems for expressing recombinant mAbs using transgenic animals or plants have been widely developed. The silkworm (Bombyx mori) is a highly domesticated insect that has recently been used for the production of recombinant proteins. Because of their cost-effective breeding and relatively easy production scale-up, transgenic silkworms show great promise as a novel production system for mAbs. In this study, we established a transgenic silkworm stably expressing a human-mouse chimeric anti-CD20 mAb having the same amino acid sequence as rituximab, and compared its characteristics with rituximab produced by Chinese hamster ovary (CHO) cells (MabThera®). The anti-CD20 mAb produced in the transgenic silkworm showed a similar antigen-binding property, but stronger antibody-dependent cell-mediated cytotoxicity (ADCC) and weaker complement-dependent cytotoxicity (CDC) compared to MabThera. Post-translational modification analysis was performed by peptide mapping using liquid chromatography/mass spectrometry. There was a significant difference in the N-glycosylation profile between the CHO− and the silkworm-derived mAbs, but not in other post-translational modifications including oxidation and deamidation. The mass spectra of the N-glycosylated peptide revealed that the observed biological properties were attributable to the characteristic N-glycan structures of the anti-CD20 mAbs produced in the transgenic silkworms, i.e., the lack of the core-fucose and galactose at the non-reducing terminal. These results suggest that the transgenic silkworm may be a promising expression system for the tumor-targeting mAbs with higher ADCC activity. PMID:26261057

  11. Veltuzumab, an anti-CD20 mAb for the treatment of non-Hodgkin's lymphoma, chronic lymphocytic leukemia and immune thrombocytopenic purpura.

    PubMed

    Milani, Cannon; Castillo, Jorge

    2009-04-01

    Veltuzumab is a humanized, second-generation anti-CD20 mAb currently under development by Immunomedics Inc for the potential treatment of B-cell non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Licensee Nycomed is developing veltuzumab for the potential treatment of rheumatoid arthritis and immune thrombocytopenic purpura (ITP). Veltuzumab contains 90 to 95% human antibody sequences with identical antigen framework regions to epratuzumab (a humanized anti-CD22 mAb) and similar antigen-binding determinants to rituximab (chimeric, anti-CD20 mAb and the first-line treatment of aggressive and indolent NHL). In vitro studies have demonstrated that veltuzumab has enhanced binding avidities and a stronger effect on complement-dependent cytotoxicity compared with rituximab in selected cell lines. In dose-finding phase I/II clinical trials in patients with low-grade NHL, intravenous veltuzumab demonstrated a substantial rate of complete responses in concurrence with shorter and more tolerable infusions compared with rituximab. Currently there has been no evidence of an immune response to repeated administrations, and no serious adverse events related to veltuzumab treatment in patients with NHL. Veltuzumab is undergoing clinical trials using a low-dose subcutaneous formulation in patients with NHL, CLL and ITP. Prospective, randomized clinical trials are needed to clarify the role veltuzumab will play in a market where the therapy of B-cell lymphoproliferative disorders is dominated by rituximab. PMID:19330725

  12. Expression and biological characterization of an anti-CD20 biosimilar candidate antibody

    PubMed Central

    Dorvignit, Denise; Palacios, Julio L.; Merino, Maylin; Hernández, Tays; Sosa, Katya; Casacó, Angel; López-Requena, Alejandro; Mateo de Acosta, Cristina

    2012-01-01

    The CD20 molecule is a non-glycosylated protein expressed mainly on the surface of B lymphocytes. In some pathogenic B cells, it shows an increased expression, thus becoming an attractive target for diagnosis and therapy. Rituximab is a chimeric antibody that specifically recognizes the human CD20 molecule. This antibody is indicated for the treatment of non-Hodgkin lymphomas and autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. In this work, we describe the stable expression and biological evaluation of an anti-CD20 biosimilar antibody. While rituximab is produced in fed-batch culture of recombinant Chinese hamster ovary (CHO) cells, our biosimilar antibody expression process consists of continuous culture of recombinant murine NS0 myeloma cells. The ability of the purified biosimilar antibody to recognize the CD20 molecule on human tumor cell lines, as well as on peripheral blood mononuclear cells from humans and primates, was demonstrated by flow cytometry. The biosimilar antibody induced complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity and apoptosis on human cell lines with high expression of CD20. In addition, this antibody depleted CD20-positive B lymphocytes from peripheral blood in monkeys. These results indicate that the biological properties of the biosimilar antibody compare favorably with those of the innovator product, and that it should be evaluated in future clinical trials. PMID:22647435

  13. Expression and biological characterization of an anti-CD20 biosimilar candidate antibody: a case study.

    PubMed

    Dorvignit, Denise; Palacios, Julio L; Merino, Maylin; Hernández, Tays; Sosa, Katya; Casaco, Angel; López-Requena, Alejandro; Mateo de Acosta, Cristina

    2012-01-01

    The CD20 molecule is a non-glycosylated protein expressed mainly on the surface of B lymphocytes. In some pathogenic B cells, it shows an increased expression, thus becoming an attractive target for diagnosis and therapy. Rituximab is a chimeric antibody that specifically recognizes the human CD20 molecule. This antibody is indicated for the treatment of non-Hodgkin lymphomas and autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. In this work, we describe the stable expression and biological evaluation of an anti-CD20 biosimilar antibody. While rituximab is produced in fed-batch culture of recombinant Chinese hamster ovary (CHO) cells, our biosimilar antibody expression process consists of continuous culture of recombinant murine NS0 myeloma cells. The ability of the purified biosimilar antibody to recognize the CD20 molecule on human tumor cell lines, as well as on peripheral blood mononuclear cells from humans and primates, was demonstrated by flow cytometry. The biosimilar antibody induced complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity and apoptosis on human cell lines with high expression of CD20. In addition, this antibody depleted CD20-positive B lymphocytes from peripheral blood in monkeys. These results indicate that the biological properties of the biosimilar antibody compare favorably with those of the innovator product, and that it should be evaluated in future clinical trials. PMID:22647435

  14. Highly potent anti-CD20-RLI immunocytokine targeting established human B lymphoma in SCID mouse.

    PubMed

    Vincent, Marie; Teppaz, Géraldine; Lajoie, Laurie; Solé, Véronique; Bessard, Anne; Maillasson, Mike; Loisel, Séverine; Béchard, David; Clémenceau, Béatrice; Thibault, Gilles; Garrigue-Antar, Laure; Jacques, Yannick; Quéméner, Agnès

    2014-01-01

    Rituximab (RTX), a chimeric IgG1 monoclonal antibody directed against the CD20 antigen, has revolutionized the treatment of B-cell malignancies. Nevertheless, the relapsed/refractory rates are still high. One strategy to increase the clinical effectiveness of RTX is based on antibody-cytokine fusion protein (immunocytokine; ICK) vectorizing together at the tumor site the antibody effector activities and the cytokine co-signal required for the generation of cytotoxic cellular immunity. Such ICKs linking various antibody formats to interleukin (IL)-2 are currently being investigated in clinical trials and have shown promising results in cancer therapies. IL-15, a structurally-related cytokine, is now considered as having a better potential than IL-2 in antitumor immunotherapeutic strategies. We have previously engineered the fusion protein RLI, linking a soluble form of human IL-15Rα-sushi+ domain to human IL-15. Compared with IL-15, RLI displayed better biological activities in vitro and higher antitumor effects in vivo in murine and human cancer models. In this study, we investigated the advantages of fusing RLI to RTX. Anti-CD20-RLI kept its binding capacity to CD20, CD16 and IL-15 receptor and therefore fully retained both antibody effector functions (ADCC and CDC), and the cytokine potential of RLI. In a severe combined immunodeficiency (SCID) mouse model of disseminated residual lymphoma, anti-CD20-RLI was found to induce long-term survival of 90% of mice up to at least 120 days whereas RLI and RTX, alone or in combination, just delayed the disease onset (100% of death at 28, 40 and 51 days respectively). These findings suggest that such ICK could improve the clinical efficacy of RTX, particularly in patients with refractory B-cell lymphoma. PMID:25072059

  15. Improving therapeutic activity of anti-CD20 antibody therapy through immunomodulation in lymphoid malignancies.

    PubMed

    Lipowska-Bhalla, Grazyna; Fagnano, Ester; Illidge, Timothy M; Cheadle, Eleanor J

    2016-06-01

    Nearly two decades ago rituximab heralded a new era in management of B cell malignancies significantly increasing response rates and survival. However, despite clear therapeutic advantage, significant numbers of patients become refractory to anti-CD20 mAb therapy, suggesting urgent improvements are required. It is now well recognized that the suppressive tumor microenvironment plays an important role in the outcome of anti-CD20 mAb therapy and that manipulation of this environment may improve the efficacy and produce long-term tumor control. The past few years have seen a surge of interest in immunomodulatory agents capable of overwriting immune suppressive networks into favorable clinical outcome. Currently, a number of such combinations with anti-CD20 mAb is under evaluation and some have produced encouraging outcomes in rituximab refractory disease. In this review, we give an outline of anti-CD20 mAbs and explore the combinations with immunomodulatory agents that enhance antitumor immunity through targeting stimulatory or inhibitory pathways and have proven potential to synergize with anti-CD20 mAb therapy. These agents, primarily mAbs, target CTLA-4, PD-1/PD-L1, and CD40. PMID:27050042

  16. Anti-CD20 monoclonal antibodies in chronic lymphocytic leukemia: from uncertainties to promises.

    PubMed

    Bagacean, Cristina; Zdrenghea, Mihnea; Tempescul, Adrian; Cristea, Victor; Renaudineau, Yves

    2016-05-01

    Over the last two decades, anti-CD20 monoclonal antibody (mAb) therapy has improved patient outcome in B-cell malignancies, and confirmed CD20 as an important target in chronic lymphocytic leukemia (CLL). Until recently, the gold standard was based on the utilization of rituximab combined with chemotherapy (fludarabine and cyclophosphamide), but patients often relapse. Next, with our better understanding of mAb engineering, anti-CD20 mAb therapy has evolved with the development of new mAb permitting significant clinical responses by improving pharmacokinetics, safety, activity and immunogenicity. Last but not least, the development of key tumoral tyrosine kinase inhibitors and their association with anti-CD20 mAb is a work in progress with promising results. PMID:27140410

  17. Inhibitors of SRC kinases impair antitumor activity of anti-CD20 monoclonal antibodies

    PubMed Central

    Winiarska, Magdalena; Bojarczuk, Kamil; Pyrzynska, Beata; Bil, Jacek; Siernicka, Marta; Dwojak, Michal; Bobrowicz, Malgorzata; Miazek, Nina; Zapala, Piotr; Zagozdzon, Agnieszka; Krol, Magdalena; Syta, Aleksandra; Podszywalow-Bartnicka, Paulina; Pilch, Zofia; Dabrowska-Iwanicka, Anna; Juszczynski, Przemyslaw; Efremov, Dimitar G; Slabicki, Mikolaj; Zenz, Thorsten; Roy, Aude Le; Olive, Daniel; Rygiel, Tomasz P; Leusen, Jeanette HW; Golab, Jakub

    2014-01-01

    Clinical trials with SRC family kinases (SFKs) inhibitors used alone or in a combination with anti-CD20 monoclonal antibodies (mAbs) are currently underway in the treatment of B-cell tumors. However, molecular interactions between these therapeutics have not been studied so far. A transcriptional profiling of tumor cells incubated with SFKs inhibitors revealed strong downregulation of MS4A1 gene encoding CD20 antigen. In a panel of primary and established B-cell tumors we observed that SFKs inhibitors strongly affect CD20 expression at the transcriptional level, leading to inhibition of anti-CD20 mAbs binding and increased resistance of tumor cells to complement-dependent cytotoxicity. Activation of the AKT signaling pathway significantly protected cells from dasatinib-triggered CD20 downregulation. Additionally, SFKs inhibitors suppressed antibody-dependent cell-mediated cytotoxicity by direct inhibition of natural killer cells. Abrogation of antitumor activity of rituximab was also observed in vivo in a mouse model. Noteworthy, the effects of SFKs inhibitors on NK cell function are largely reversible. The results of our studies indicate that development of optimal combinations of novel treatment modalities with anti-CD20 mAbs should be preceded by detailed preclinical evaluation of their effects on target cells. PMID:25517315

  18. A new approach to comparing anti-CD20 antibodies: importance of the lipid rafts in their lytic efficiency

    PubMed Central

    Hammadi, Mariam; Pers, Jacques-Olivier; Berthou, Christian; Youinou, Pierre; Bordron, Anne

    2010-01-01

    The view that B lymphocytes are pathogenic in diverse pathological settings is supported by the efficacy of B-cell-ablative therapy in lymphoproliferative disorders, autoimmune diseases and graft rejection. Anti-B-cell antibodies (Abs) directed against CD20 have therefore been generated, and of these, rituximab was the first anti-CD20 monoclonal Ab (mAb) to be applied. Rituximab-mediated apoptosis, complement-dependent cytotoxicity and Ab-dependent cellular cytotoxicity differ from one disease to another, and, for the same disease, from one patient to another. This knowledge has prompted the development of new anti-CD20 mAbs in the hope of improving B-cell depletion. The inclusion of CD20/anti-CD20 complexes in large lipid rafts (LRs) enhances the results of some, but not all, anti-CD20 mAbs, and it may be possible to include smaller LRs. Lipid contents of membrane may be abnormal in malignant B-cells, and could explain resistance to treatment. The function of these mAbs and the importance of LRs warrant further investigation. A detailed understanding of them will increase results for B-cell depletion in lymphoproliferative diseases. PMID:20616960

  19. A case of multicentric Castleman's disease associated with advanced systemic amyloidosis treated with chemotherapy and anti-CD20 monoclonal antibody.

    PubMed

    Gholam, Dany; Vantelon, Jean-Marie; Al-Jijakli, Ahmad; Bourhis, Jean-Henri

    2003-12-01

    Multicentric Castleman's disease (MCD) is a rare systemic lymphoproliferative disorder with too few patient series reported in the literature to have a clear idea about the etiology, outcome and the best treatment available. Systemic reactive amyloidosis is a very rare complication of MCD and its presence worsens the prognosis. We report a case of a 28-year-old patient with plasma-cell type, human immunodeficiency virus (HIV)-negative and human herpesvirus-8 (HHV-8)-negative MCD who responded to treatment with chemotherapy and the anti-CD20 monoclonal antibody, rituximab. Anti-CD20 therapy could be an interesting adjunctive treatment in MCD. PMID:12898190

  20. Two cases of refractory Wegener's granulomatosis successfully treated with rituximab.

    PubMed

    Tamura, Naoto; Matsudaira, Ran; Hirashima, Mika; Ikeda, Makoto; Tajima, Michiko; Nawata, Masuyuki; Morimoto, Shinji; Kaneda, Kazuhiko; Kobayashi, Shigeto; Hashimoto, Hiroshi; Takasaki, Yoshinari

    2007-01-01

    Conventional therapy for Wegener's granulomatosis, steroid and cyclophosphamide, fails to control disease activity in some refractory patients and has treatment-related toxicity. B cell depletion therapy using rituximab, a chimeric anti-CD20 monoclonal antibody, has been shown to be effective for certain autoimmune diseases including antineutrophil cytoplasmic antibody (ANCA) -associated systemic vasculitis. We report two refractory cases of Wegener's granulomatosis: one with bronchial and pulmonary involvement and retroorbital granuloma, the other with retroorbital granuloma and hypertrophic pachymeningitis causing severe headache. Rituximab was effective in both cases, with diminished granuloma and reduced ANCA titers, allowing steroids to be tapered. No adverse effects were detected. PMID:17409608

  1. [Intravascular lymphoma treated with anti CD20 monoclonal antibodies. Report of one case].

    PubMed

    Alfaro, Jorge; Espinoza, Arturo; Manŕiquez, María; Moyano, Leonor; González, Néstor; Larrondo, Milton; Figueroa, Gastón

    2004-11-01

    We report a 78 year old male with prostatism, that was subjected to a prostate biopsy. The pathological study showed a microvascular lymphocytic infiltration. Four months later, the patients presented with reduced alertness, cough, dyspnea, fever and elevation of lactic dehydrogenase and erythrocyte sedimentation rate. Chest and abdominal CAT scans, bone marrow aspirate, protein electrophoresis and prostate specific antigen were normal. A re-evaluation of prostate biopsy showed an intravascular lymphoid infiltration, positive for CD45 and CD20, compatible with the diagnosis of intravascular lymphoma. Chemotherapy was started, but it was not tolerated by the patient and the response was partial. Therefore, treatment with monoclonal antibodies anti CD20 (Rituximab) was started. The tumor had a complete and prolonged (24 months) remission after the treatment PMID:15693204

  2. Anti-CD137 enhances anti-CD20 therapy of systemic B-cell lymphoma with altered immune homeostasis but negligible toxicity.

    PubMed

    Souza-Fonseca-Guimaraes, Fernando; Blake, Stephen J; Makkouk, Amani; Chester, Cariad; Kohrt, Holbrook E; Smyth, Mark J

    2016-07-01

    Studies of sequential anti-CD137/anti-CD20 therapy have previously shown that the efficacy of anti-CD20 was heavily reliant upon anti-CD137; however, the exact mechanism of the anti-B-cell lymphoma efficacy, and whether this correlates with enhanced adverse effects or toxicity, had not been elucidated. Here, we observed that sequential anti-CD137 administration with anti-CD20 resulted in a synergistic therapy, largely dependent upon Fc receptors (FcR), to prolong survival in an experimental B-cell lymphoma therapy model. Tumor suppression was accompanied by B cell depletion, which was not dependent on one activating FcR. Surprisingly, the B-cell activating factor (BAFF) was elevated in the plasma of mice receiving anti-CD137 alone or in combination with anti-CD20, while a selective increase in some plasma cytokines was also noted and triggered by anti-CD137. These effects were independent of activating FcR. Sustained treatment of advanced lymphoma revealed increased lymphocyte infiltrates into the liver and a significant decrease in the metabolic capability of the liver in mice receiving anti-CD137. Importantly, these effects were not exacerbated in mice receiving the anti-CD20/CD137 combination, and elevations in classical liver damage markers such as alanine aminotransferase (ALT) were less than that caused by the lymphoma itself. Thus, combined anti-CD20/anti-CD137 treatment increases the therapeutic index of anti-CD20 or anti-CD137 alone. These mouse data were corroborated by ongoing clinical development studies to assess safety, tolerability and pharmacodynamic activity of human patients treated by this approach. Together, these data support the use of this sequential antibody therapeutic strategy to improve the efficacy of rituximab in B-cell lymphoma patients. PMID:27622048

  3. Rituximab and chemotherapy in diffuse large B-cell lymphoma.

    PubMed

    Sonet, Anne; Bosly, André

    2009-06-01

    Rituximab is an anti-CD20 chimeric monoclonal antibody with activity in nearly all subtypes of B-cell lymphomas. Association of rituximab with chemotherapy (mostly the cyclophosphamide, doxorubicin, vincristine and prednisolone [CHOP] regimen) in diffuse large B-cell lymphoma (DLBCL) represents an extraordinary revolution in the prognosis of DLBCL, and is the new standard of therapy in elderly and young, low-risk patients. Despite the lack of randomized, clinical trials in younger patients with high risk, rituximab is also a standard of care in these patients in clinical practice, at least in North America. The practice is based on observational trials (e.g., the British Columbia Registry) and the missing logic in classifying patients as 'younger' or 'older': 60 years old or 65 years old. In Europe, trials are ongoing to establish the best treatment for young, high-risk patients. Association of rituximab and chemotherapy deeply modifies prognostic factors defined before the rituximab era. PMID:19496708

  4. Intratumoral but not systemic delivery of CpG oligodeoxynucleotide augments the efficacy of anti-CD20 monoclonal antibody therapy against B cell lymphoma.

    PubMed

    Betting, David J; Yamada, Reiko E; Kafi, Kamran; Said, Jonathan; van Rooijen, Nico; Timmerman, John M

    2009-01-01

    The anti-CD20 monoclonal antibody rituximab (Rituxan) has become a mainstay in the treatment of B cell non-Hodgkin lymphomas. The mechanisms of action for rituximab include antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity, and apoptosis induction. Combination of anti-CD20 antibodies with immunostimulatory agents may improve their efficacy via enhancement of one or more of these mechanisms. Toll-like receptor 9 agonist CpG oligodeoxynucleotides administered systemically have been studied in clinical trials with and without rituximab. However, recent data suggest that intratumoral (IT) delivery of CpG has advantages in the treatment of tumors. Using a syngeneic murine B cell lymphoma line expressing human CD20, we found that IT, but not systemically administered CpG significantly improved the efficacy of rituximab against 7-day established tumors. Rituximab plus IT CpG could eradicate tumors from 42% of mice, whereas systemically administered CpG, with or without rituximab, did not achieve tumor eradication. Both natural killer cells and complement participated in the cure of tumors by rituximab plus IT CpG, apparently by increasing tumor cell sensitivity to complement and ADCC lysis, and by augmenting the cytotoxicity of ADCC effectors. No role for T cells in mediating tumor eradication was demonstrated in this model. These results suggest that previous clinical trials in B cell lymphoma combining systemic administration of CpG with rituximab may have employed suboptimal routes of CpG delivery. Future trials combining IT CpG with anti-CD20 antibodies or the antibody-mediated targeting of CpG directly to the sites of B cell lymphoma may thus be warranted. PMID:19483647

  5. [One amino acid mutation in an anti-CD20 antibody fragment that affects the yield bacterial secretion and the affinity].

    PubMed

    Liu, Yin-Xing; Xiong, Dong-Sheng; Fan, Dong-Mei; Shao, Xiao-Feng; Xu, Yuan-Fu; Zhu, Zhen-Ping; Yang, Chun-Zheng

    2003-05-01

    Monoclonal antibodies (mAb) directed against CD20, either unmodified or in radiolabeled forms, have been successfully exploited in clinic as effective therapeutic agents in the management of non-Hodgkin's B-cell lymphoma. The antibody fragment is a potential agent in image and therapy of tumor. To further improve the soluble expression of anti-CD20 antibody Fab' fragment, PCR was used to mutate the anti-CD20 VL and VH genes and its biological activity was identified. The expression vector of chimeric antibody Fab' was constructed and expressed in E. coli. The data of mutant clone DNA sequence showed that the amino acid of light chain gene of the parent anti-CD20 antibody (H47) was successful mutated as Ser (GAG)-Asn (CAG). The soluble expression of mutated anti-CD20 Fab' (CD20-7) was 3.8 mg/g dry cell weight, while the parent (CD20-2) was 1.3 mg/g dry cell weight. The affinity constant Ka of CD20-7 was 2.2 x 10(9) L/mol. The primary results of competitive assays by FACS showed that CD20-7 could partially block the sites through which parent antibody (HI47) bind to Raji cells. There was difference in the Raji cells (CD20+)-binding activity between the mutant CD20-7 and parent CD20-2. The site mutation of anti-CD20 Fab' gene make it possible that the anti-CD20 antibody fragment was succeeded to obtain higher expression. In this thesis, we succeeded in completing mutation and expression of anti-CD20 Fab' genes, distinguishing its biological activity, and obtaining its highly expression. These period results will lay a foundation for development of other kind of anti-CD20 engineering antibody (for instance: Fab' Diabody and miniantibody), and make it possible for anti-CD20 antibody to be applied to tumor therapy in civil in the future. PMID:15969005

  6. Recurrent inflammatory pseudotumor of the jaw with perineural intracranial invasion demonstrating sustained response to Rituximab.

    PubMed

    Garcia, Bryan A; Tinsley, Sarah; Schellenberger, Thomas; Bobustuc, George C

    2012-12-01

    Corticosteroids are the mainstay of treatment of inflammatory pseudotumor (IPT) of the head and neck; however, involvement of the skull base and mandible can be unresponsive to steroids and require surgical resection. IPT is known to usually contain a CD20+ lymphocyte subgroup. Rituximab, a chimeric anti-CD20 antibody, has been successfully utilized in the treatment of other CD20+ diseases, including the similar idiopathic orbital inflammatory disease. This is the first report to describe successful treatment with Rituximab of a recurrent IPT of the mandible with trigeminal spread and leptomeningeal involvement with clinical and radiologic evidence demonstrating a sustained response to therapy. PMID:22161155

  7. Bi20 (fBTA05), a novel trifunctional bispecific antibody (anti-CD20 x anti-CD3), mediates efficient killing of B-cell lymphoma cells even with very low CD20 expression levels.

    PubMed

    Stanglmaier, Michael; Faltin, Margot; Ruf, Peter; Bodenhausen, Annette; Schröder, Petra; Lindhofer, Horst

    2008-09-01

    Trifunctional bispecific antibodies can efficiently mediate tumor cell killing by redirecting T cells and immune accessory cells to the tumor cell. Here, we describe the new trifunctional antibody, Bi20 (FBTA05, anti-CD20 x anti-CD3), that connects B cells and T cells via its variable regions and recruits FcgammaRI(+) accessory immune cells via its Fc region. Bi20 mediated efficient and specific lysis of B-cell lines and of B cells with low CD20 expression levels that were derived from CLL patients. Remarkably, T-cell activation and tumor cell killing occurred in an entirely autologous setting without additional effector cells in 5 of 8 samples. In comparison, rituximab, a chimeric monoclonal CD20 antibody, demonstrated a significantly lower B-cell eradication rate. Additionally, Bi20, but not rituximab, upregulated the activation markers CD25 and CD69 on both CD4(+) and CD8(+) T cells in the presence of accessory immune cells. CD14(+) accessory cells and the monocyte cell line THP-1 were activated via binding of the Fc region of Bi20, given that T cells were simultaneously engaged by the antibody. Bi20 induced a strong Th1 cytokine pattern characterized by high IFN-gamma and very low IL-4 secretion. In conclusion, Bi20 may offer new immunotherapeutic options for the treatment of B-cell lymphomas. PMID:18546289

  8. Novel humanized anti-CD20 antibody BM-ca binds to a unique epitope and exerts stronger cellular activity than others

    PubMed Central

    Kobayashi, Hideaki; Matsunaga, Yuka; Uchiyama, Yumiko; Nagura, Kenji; Komatsu, Yasuhiko

    2013-01-01

    Cellular activity of BM-ca, a novel humanized anti-CD20 antibody, was quantitatively compared with that of two other anti-CD20 antibodies used for clinical practice, rituximab and ofatumumab. The results of a complement-dependent cytotoxicity (CDC) assay revealed that the strongest antibody was ofatumumab, followed by BM-ca, with rituximab being the weakest. Ofatumumab and BM-ca were effective not only against rituximab-sensitive SU-DHL-4 cells but also against rituximab-resistant RC-K8 cells. In an antibody-dependent cell-mediated cytotoxicity (ADCC) assay, although the effective concentrations against SU-DHL-4 cells were almost the same among these three antibodies, the maximum cytotoxic level was the highest for BM-ca. In an anti-cell proliferation assay using SU-DHL-4 cells, BM-ca was the most effective and ofatumumab, the weakest. Against RC-K8 cells, only BM-ca was effective. When combined with each of four cancer chemotherapeutics (prednisolone, vincristine, hydroxydaunorubicin, and cisplatin), BM-ca exerted the most effective combinatorial anti-cell proliferation activity. To assess the in vivo effect of BM-ca, we intravenously administered BM-ca into cynomolgus monkeys and found that the peripheral B-cell levels did not decrease in half of the animals. Sequencing of cDNA encoding CD20 of cynomolgus monkeys revealed that the responders and nonresponders had Leu/Pro (hetero) and Leu/Leu (homo) at amino acid (a.a.) position 160, respectively, suggesting that the epitope recognized by BM-ca was around this a.a. By analyzing reactivity to synthetic peptides, the epitope recognized by BM-ca was estimated to be a.a.'s 156–166, not shared with rituximab and ofatumumab. These results suggest BM-ca to be a promising anti-CD20 antibody having superior properties and recognizing a unique epitope. PMID:23634281

  9. Rituximab use in adult primary glomerulopathy: where is the evidence?

    PubMed Central

    Mallat, Samir G; Itani, Houssam S; Abou-Mrad, Rana M; Abou Arkoub, Rima; Tanios, Bassem Y

    2016-01-01

    Rituximab is a chimeric anti-CD20 antibody that results in depletion of B-cell lymphocytes. It is currently used in the treatment of a variety of autoimmune diseases, in addition to CD20-positive lymphomas. The use of rituximab in the treatment of the adult primary glomerular diseases has emerged recently, although not yet established as first-line therapy in international guidelines. In patients with steroid-dependent minimal change disease or frequently relapsing disease, and in patients with idiopathic membranous nephropathy (IMN), several retrospective and prospective studies support the use of rituximab to induce remission, whereas in idiopathic focal and segmental glomerulosclerosis (FSGS), the use of rituximab has resulted in variable results. Evidence is still lacking for the use of rituximab in patients with immunoglobulin A nephropathy (IgAN) and idiopathic membranoproliferative glomerulonephritis (MPGN), as only few reports used rituximab in these two entities. Randomized controlled trials (RCTs) are warranted and clearly needed to establish the definitive role of rituximab in the management of steroid-dependent and frequently relapsing minimal change disease, IMN, both as first-line and second-line treatment, and in MPGN. We await the results of an ongoing RCT of rituximab use in IgAN. Although current evidence for the use of rituximab in patients with idiopathic FSGS is poor, more RCTs are needed to clarify its role, if any, in the management of steroid-resistant or steroid-dependent FSGS. PMID:27621641

  10. Recombinant anti-CD20 antibody fragments for microPET imaging of B-cell lymphoma

    PubMed Central

    Olafsen, Tove; Betting, David; Kenanova, Vania E.; Salazar, Felix B.; Clarke, Pat; Said, Jonathan; Raubitschek, Andrew A.; Timmerman, John M.; Wu, Anna M.

    2010-01-01

    The CD20 cell surface antigen is expressed at high levels by over 90% of B cell non-Hodgkin lymphomas (NHL), and is the target of the anti-CD20 monoclonal antibody rituximab. To provide more sensitive, tumor-specific positron emission tomography (PET) imaging of NHL, we sought to develop PET imaging agents targeting CD20. Methods Two recombinant anti-CD20 rituximab fragments, a minibody (scFv-CH3 dimer, 80 kDa) and a modified scFv-Fc fragment (105 kDa), designed to clear rapidly, were generated. Both fragments were radiolabeled with 124I, and the minibody was additionally radiometal labeled with 64Cu following conjugation to 1,4,7,10-tetraazacyclododecane-N,N’,N’’,N’’’-tetraacetic acid (DOTA). The radioiodinated fragments and the radiometal labeled minibody were evaluated in mice as microPET imaging agents for in vivo imaging of human CD20-expressing lymphomas. Results Rapid and specific localization to CD20-positive tumors was observed with the radioiodinated fragments. However, their tumor uptakes and blood activities differed, resulting in different levels of contrast in the images. The best candidate was the minibody, with superior uptake (2-fold higher than the scFv-Fc) in CD20-positive tumor and low uptake in CD20-negative tumor. Positive tumor to negative tumor ratios were 7.0(±3.1) and 3.9(±0.7) for the minibody and scFv-Fc, respectively at 21 hours. About a 5-fold lower ratio was achieved with the 64Cu-DOTA-minibody at 19 hours due to higher residual background activity in CD20 negative tumor. Conclusion Radioiodinated minibody and scFv-Fc fragment produced excellent, high-contrast images in vivo. These new immunoPET agents may prove useful for the imaging CD20 positive lymphomas in preclinical models and in humans with NHL. PMID:19690034

  11. Efficient inhibition of B-cell lymphoma xenografts with a novel recombinant fusion protein: anti-CD20Fab-LDM.

    PubMed

    Xin, C; Ye, S; Ming, Y; Shenghua, Z; Qingfang, M; Hongxing, G; Xu, S; Yuanfu, X; Yuan, Z; Dongmei, F; Juanni, L; Yingdai, G; Lianfang, J; Rongguang, S; Zhenping, Z; Jianxiang, W; Tao, C; Chunzheng, Y; Dongsheng, X; Yongsu, Z

    2010-10-01

    Lidamycin (LDM) is a new member of enediyne antitumor antibiotics family that can be separated and reconstituted. It consists of a labile active enediyne chromophore (AE) and a noncovalently bound apoprotein (LDP). LDM is now in phase II clinical trials. In this study, we described the antitumor features of a fusion protein of LDM, anti-CD20Fab-LDM, targeted to CD20 expressed by B-lymphoid malignancies. Especially, LDM was prepared by a novel two-step method including DNA recombination and molecular reconstitution. Anti-CD20Fab-LDM exerted potent cytotoxicity against CD20+ B-cell lymphoma cell lines in vitro (IC50: 10-30 pM) and in the Raji xenograft model. Two Raji xenografts were allowed to grow to an initial mass of 80 and 500 mm³, respectively, and then anti-CD20Fab-LDM was administered intravenously with the highest dose of 4 nmol kg⁻¹ . The inhibition rates of tumor growth were 90.1 and 85%, which were saliently superior to those of nontargeted LDM. It is noteworthy that anti-CD20Fab-LDM can inhibit the growth of patient-derived cells, including rituximab-resistant patient-derived cells. Thus, CD20-targeted delivery of LDM is a specific and potent therapeutic strategy for B-lymphoid malignancies. In addition, the two-step approach could serve as a new technology platform for making a series of highly potent engineered antibody-based drugs. PMID:20463754

  12. Construction and characterization of an anti-CD20 mAb nanocomb with exceptionally excellent lymphoma-suppressing activity

    PubMed Central

    Li, Hua-Fei; Wu, Cong; Chen, Ting; Zhang, Ge; Zhao, He; Ke, Chang-Hong; Xu, Zheng

    2015-01-01

    The CD20-directed monoclonal antibody rituximab (RTX) established a new era in the treatment of non-Hodgkin lymphoma (NHL); however, suboptimal response and/or resistance to RTX still limit its clinical merits. Although four effector mechanisms are validated to participate in CD20-based immunotherapy, including complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, caspase-dependent apoptosis, and lysosome-mediated programmed cell death (PCD), they could hardly be synchronously activated by any anti-CD20 mAb or mAb derivative until now. Herein, a novel mAb nanocomb (polyethylenimine polymer–RTX–tositumomab [PPRT nanocomb]) was firstly constructed through mass arming two different anti-CD20 mAbs (RTX and tositumomab) to one polymer by nanotechnology. Comparing with free mAbs, PPRT nanocomb possesses a comparable binding ability and reduced “off-rate” to surface CD20 of NHL cells. When treated by PPRT nanocomb, the caspase-dependent apoptosis was remarkably enhanced except for concurrently eliciting complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and lysosome-mediated PCD. Besides, “cross-cell link”-assisted homotypic adhesion by PPRT nanocomb further enhanced the susceptibility to PCD of lymphoma cells. Pharmacokinetic assays revealed that PPRT nanocomb experienced a relatively reduced clearance from peripheral blood compared with free antibodies. With the cooperation of all the abovementioned superiorities, PPRT nanocomb exhibits exceptionally excellent in vivo antitumor activities in both disseminated and localized human NHL xenotransplant models. PMID:26257518

  13. The spectrum of use of rituximab in chronic lymphocytic leukemia

    PubMed Central

    Tedeschi, Alessandra; Vismara, Eleonora; Ricci, Francesca; Morra, Enrica; Montillo, Marco

    2010-01-01

    The monoclonal chimeric anti-CD20 antibody, rituximab, has considerably improved therapeutic outcome in B-cell chronic lymphocytic leukemia. Rituximab has limited clinical activity when used as a single agent. The combination of the monoclonal antibody with fludarabine-based regimens clearly demonstrated, in Phase II and randomized trials, an increase in clinical efficacy in previously untreated and pretreated patients. Furthermore the addition of rituximab enabled the eradication of minimal residual disease, which is correlated with the prognosis in a high proportion of patients. Although the combination of rituximab with fludarabine-based regimens increased myelosuppression and immunosuppression, incidence of infections did not increase. The benefit of adding rituximab to other purine analogs or other chemotherapeutic combination regimens has also been explored. Moreover there could be a role for achieving better quality of responses with the combination of different monoclonal antibodies, considering that they target different antigens and exert different mechanism of action. Although the role of rituximab as maintenance therapy in low grade non-Hodgkin’s lymphomas has been determined, the benefit and optimal schedule in chronic lymphocytic leukemia are still under investigation. This review brings together knowledge of the pharmacokinetics, mechanism of action and clinical use of rituximab in chronic lymphocytic leukemia. PMID:21289858

  14. [Advances in the research of anti-CD20 therapeutic monoclonal antibodies].

    PubMed

    Deng, Cheng-Lian; Zou, Jia; Song, Hai-Feng

    2013-10-01

    As targeted drugs to B-cell malignancies, anti-CD20 monoclonal antibodies have been proved to be important in therapeutic antibody field. With three generations in more than ten years' development, the structures of these drugs have been improved, and many new indications have been found. Nowadays, these kinds of antibodies are not only used in the treatment of lymphoid malignancies, but also been proved to be useful in some autoimmune diseases treatment, and their new indications are still being expanded. With the optimization of their clinical dosage regimens, drug reaction has been increased, thus, therapeutic and side effects of anti-CD20 monoclonal antibody have been further improved as well. However, the exact mechanism of action of their combination therapy with other chemical drugs is still unclear, which remains to be further studied. This article reviewed new development of anti-CD20 therapeutic monoclonal antibodies research in recent years. PMID:24417077

  15. Anti-CD20 inhibits T cell-mediated pathology and microgliosis in the rat brain

    PubMed Central

    Anthony, Daniel C; Dickens, Alex M; Seneca, Nicholas; Couch, Yvonne; Campbell, Sandra; Checa, Begona; Kersemans, Veerle; Warren, Edward A; Tredwell, Matthew; Sibson, Nicola R; Gouverneur, Veronique; Leppert, David

    2014-01-01

    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) model, which is a focal demyelinating type-IV delayed-type hypersensitivity lesion. For comparison, effects were also assessed in the focal humoral MOG model induced by intracerebral injection of cytokine in myelin oligodendrocyte glycoprotein immunized rats. Microglial activation was assessed in situ and in vivo using the TSPO SPECT ligand [125I]DPA-713, and by immunostaining for MHCII. The effect of treatment on demyelination and lymphocyte recruitment to the brain were evaluated. Results Anti-CD20 therapy reduced microglial activation, and lesion formation in the humoral model, but it was most effective in the antibody-independent fDTH-EAE. Immunohistochemistry for MHCII also demonstrated a reduced volume of microglial activation in the brains of anti-CD20-treated fDTH-EAE animals, which was accompanied by a reduction in T-cell recruitment and demyelination. The effect anti-CD20 therapy in the latter model was similarly strong as compared to the T-cell targeting MS compound FTY720. Interpretation The suppression of lesion development by anti-CD20 treatment in an antibody-independent model suggests that B-cells play an important role in lesion development, independent of auto-antibody production. Thus, CD20-positive B-cell depletion has the potential to be effective in a wider population of individuals with MS than might have been predicted from our knowledge of the underlying histopathology. PMID:25493280

  16. Veterans health administration hepatitis B testing and treatment with anti-CD20 antibody administration

    PubMed Central

    Hunt, Christine M; Beste, Lauren A; Lowy, Elliott; Suzuki, Ayako; Moylan, Cynthia A; Tillmann, Hans L; Ioannou, George N; Lim, Joseph K; Kelley, Michael J; Provenzale, Dawn

    2016-01-01

    AIM: To evaluate pretreatment hepatitis B virus (HBV) testing, vaccination, and antiviral treatment rates in Veterans Affairs patients receiving anti-CD20 Ab for quality improvement. METHODS: We performed a retrospective cohort study using a national repository of Veterans Health Administration (VHA) electronic health record data. We identified all patients receiving anti-CD20 Ab treatment (2002-2014). We ascertained patient demographics, laboratory results, HBV vaccination status (from vaccination records), pharmacy data, and vital status. The high risk period for HBV reactivation is during anti-CD20 Ab treatment and 12 mo follow up. Therefore, we analyzed those who were followed to death or for at least 12 mo after completing anti-CD20 Ab. Pretreatment serologic tests were used to categorize chronic HBV (hepatitis B surface antigen positive or HBsAg+), past HBV (HBsAg-, hepatitis B core antibody positive or HBcAb+), resolved HBV (HBsAg-, HBcAb+, hepatitis B surface antibody positive or HBsAb+), likely prior vaccination (isolated HBsAb+), HBV negative (HBsAg-, HBcAb-), or unknown. Acute hepatitis B was defined by the appearance of HBsAg+ in the high risk period in patients who were pretreatment HBV negative. We assessed HBV antiviral treatment and the incidence of hepatitis, liver failure, and death during the high risk period. Cumulative hepatitis, liver failure, and death after anti-CD20 Ab initiation were compared by HBV disease categories and differences compared using the χ2 test. Mean time to hepatitis peak alanine aminotransferase, liver failure, and death relative to anti-CD20 Ab administration and follow-up were also compared by HBV disease group. RESULTS: Among 19304 VHA patients who received anti-CD20 Ab, 10224 (53%) had pretreatment HBsAg testing during the study period, with 49% and 43% tested for HBsAg and HBcAb, respectively within 6 mo pretreatment in 2014. Of those tested, 2% (167/10224) had chronic HBV, 4% (326/7903) past HBV, 5% (427

  17. Multiple signaling pathways induced by hexavalent, monospecific, anti-CD20 and hexavalent, bispecific, anti-CD20/CD22 humanized antibodies correlate with enhanced toxicity to B-cell lymphomas and leukemias.

    PubMed

    Gupta, Pankaj; Goldenberg, David M; Rossi, Edmund A; Chang, Chien-Hsing

    2010-10-28

    We have generated hexavalent antibodies (HexAbs) comprising 6 Fabs tethered to one Fc of human IgG1. Three such constructs, 20-20, a monospecific HexAb comprising 6 Fabs of veltuzumab (humanized anti-CD20 immunoglobulin G1κ [IgG1κ]), 20-22, a bispecific HexAb comprising veltuzumab and 4 Fabs of epratuzumab (humanized anti-CD22 IgG1κ), and 22-20, a bispecific HexAb comprising epratuzumab and 4 Fabs of veltuzumab, were previously shown to inhibit pro-liferation of several lymphoma cell lines at nanomolar concentrations in the absence of a crosslinking antibody. We now report an in-depth analysis of the apoptotic and survival signals induced by the 3 HexAbs in Burkitt lymphomas and provide in vitro cytotoxicity data for additional lymphoma cell lines and also chronic lymphocytic leukemia patient specimens. Among the key findings are the significant increase in the levels of phosphorylated p38 and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) by all 3 HexAbs and the notable differences in the signaling events triggered by the HexAbs from those incurred by crosslinking veltuzumab or rituximab with a secondary antibody. Thus, the greatly enhanced direct toxicity of these HexAbs correlates with their ability to alter the basal expression of various intracellular proteins involved in regulating cell growth, survival, and apoptosis, with the net outcome leading to cell death. PMID:20628151

  18. Anti-CD20 Therapy Acts via FcγRIIIA to Diminish Responsiveness of Human Natural Killer Cells.

    PubMed

    Capuano, Cristina; Romanelli, Maddalena; Pighi, Chiara; Cimino, Giuseppe; Rago, Angela; Molfetta, Rosa; Paolini, Rossella; Santoni, Angela; Galandrini, Ricciarda

    2015-10-01

    Natural killer (NK) immune cells mediate antibody-dependent cellular cytotoxicity (ADCC) by aggregating FcγRIIIA/CD16, contributing significantly to the therapeutic effect of CD20 monoclonal antibodies (mAb). In this study, we show that CD16 ligation on primary human NK cells by the anti-CD20 mAb rituximab or ofatumumab stably impairs the spontaneous cytotoxic response attributable to cross-tolerance of several unrelated NK-activating receptors (including NKG2D, DNAM-1, NKp46, and 2B4). Similar effects were obtained from NK cells isolated from patients with chronic lymphocytic leukemia in an autologous setting. NK cells rendered hyporesponsive in this manner were deficient in the ability of these cross-tolerized receptors to phosphorylate effector signaling molecules critical for NK cytotoxicity, including SLP-76, PLCγ2, and Vav1. These effects were associated with long-lasting recruitment of the tyrosine phosphatase SHP-1 to the CD16 receptor complex. Notably, pharmacologic inhibition of SHP-1 with sodium stibogluconate counteracted CD20 mAb-induced NK hyporesponsiveness, unveiling an unrecognized role for CD16 as a bifunctional receptor capable of engendering long-lasting NK cell inhibitory signals. Our work defines a novel mechanism of immune exhaustion induced by CD20 mAb in human NK cells, with potentially negative implications in CD20 mAb-treated patients where NK cells are partly responsible for clinical efficacy. PMID:26229120

  19. Preserved Activity of CD20-Specific Chimeric Antigen Receptor-Expressing T Cells in the Presence of Rituximab.

    PubMed

    Rufener, Gregory A; Press, Oliver W; Olsen, Philip; Lee, Sang Yun; Jensen, Michael C; Gopal, Ajay K; Pender, Barbara; Budde, Lihua E; Rossow, Jeffrey K; Green, Damian J; Maloney, David G; Riddell, Stanley R; Till, Brian G

    2016-06-01

    CD20 is an attractive immunotherapy target for B-cell non-Hodgkin lymphomas, and adoptive transfer of T cells genetically modified to express a chimeric antigen receptor (CAR) targeting CD20 is a promising strategy. A theoretical limitation is that residual serum rituximab might block CAR binding to CD20 and thereby impede T cell-mediated anti-lymphoma responses. The activity of CD20 CAR-modified T cells in the presence of various concentrations of rituximab was tested in vitro and in vivo CAR-binding sites on CD20(+) tumor cells were blocked by rituximab in a dose-dependent fashion, although at 37°C blockade was incomplete at concentrations up to 200 μg/mL. T cells with CD20 CARs also exhibited modest dose-dependent reductions in cytokine secretion and cytotoxicity, but not proliferation, against lymphoma cell lines. At rituximab concentrations of 100 μg/mL, CAR T cells retained ≥50% of baseline activity against targets with high CD20 expression, but were more strongly inhibited when target cells expressed low CD20. In a murine xenograft model using a rituximab-refractory lymphoma cell line, rituximab did not impair CAR T-cell activity, and tumors were eradicated in >85% of mice. Clinical residual rituximab serum concentrations were measured in 103 lymphoma patients after rituximab therapy, with the median level found to be only 38 μg/mL (interquartile range, 19-72 μg/mL). Thus, despite modest functional impairment in vitro, the in vivo activity of CD20-targeted CAR T cells remains intact at clinically relevant levels of rituximab, making use of these T cells clinically feasible. Cancer Immunol Res; 4(6); 509-19. ©2016 AACRSee related Spotlight by Sadelain, p. 473. PMID:27197068

  20. ImmunoPET imaging of B-cell lymphoma using 124I-anti-CD20 scFv dimers (diabodies).

    PubMed

    Olafsen, Tove; Sirk, Shannon J; Betting, David J; Kenanova, Vania E; Bauer, Karl B; Ladno, Waldemar; Raubitschek, Andrew A; Timmerman, John M; Wu, Anna M

    2010-04-01

    Rapid clearing engineered antibody fragments for immunoPET promise high sensitivity at early time points. Here, tumor targeting of anti-CD20 diabodies (scFv dimers) for detection of low-grade B-cell lymphomas were evaluated. In addition, the effect of linker length on oligomerization of the diabody was investigated. Four rituximab scFv variants in the V(L)-V(H) orientation with different linker lengths between the V domains (scFv-1, scFv-3, scFv-5, scFv-8), plus the scFv-5 with a C-terminal cysteine (Cys-Db) for site-specific modification were generated. The scFv-8 and Cys-Db were radioiodinated with (124)I for PET imaging, and biodistribution of (131)I-Cys-Db was carried out at 2, 4 10 and 20 h. The five anti-CD20 scFv variants were expressed as fully functional dimers. Shortening the linker to three or one residue did not produce higher order of multimers. Both (124)I-labeled scFv-8 and Cys-Db exhibited similar tumor targeting at 8 h post injection, with significantly higher uptakes than in control tumors (P < 0.05). At 20 h, less than 1% ID/g of (131)I-labeled Cys-Db was present in tumors and tissues. Specific tumor targeting and high contrast images were achieved with the anti-CD20 diabodies. These agents extend the repertoire of reagents that can potentially be used to improve detection of low-grade lymphomas. PMID:20053640

  1. ImmunoPET imaging of B-cell lymphoma using 124I-anti-CD20 scFv dimers (diabodies)

    PubMed Central

    Olafsen, Tove; Sirk, Shannon J.; Betting, David J.; Kenanova, Vania E.; Bauer, Karl B.; Ladno, Waldemar; Raubitschek, Andrew A.; Timmerman, John M.; Wu, Anna M.

    2010-01-01

    Rapid clearing engineered antibody fragments for immunoPET promise high sensitivity at early time points. Here, tumor targeting of anti-CD20 diabodies (scFv dimers) for detection of low-grade B-cell lymphomas were evaluated. In addition, the effect of linker length on oligomerization of the diabody was investigated. Four rituximab scFv variants in the VL–VH orientation with different linker lengths between the V domains (scFv-1, scFv-3, scFv-5, scFv-8), plus the scFv-5 with a C-terminal cysteine (Cys-Db) for site-specific modification were generated. The scFv-8 and Cys-Db were radioiodinated with 124I for PET imaging, and biodistribution of 131I-Cys-Db was carried out at 2, 4 10 and 20 h. The five anti-CD20 scFv variants were expressed as fully functional dimers. Shortening the linker to three or one residue did not produce higher order of multimers. Both 124I-labeled scFv-8 and Cys-Db exhibited similar tumor targeting at 8 h post injection, with significantly higher uptakes than in control tumors (P < 0.05). At 20 h, less than 1% ID/g of 131I-labeled Cys-Db was present in tumors and tissues. Specific tumor targeting and high contrast images were achieved with the anti-CD20 diabodies. These agents extend the repertoire of reagents that can potentially be used to improve detection of low-grade lymphomas. PMID:20053640

  2. Development of Novel Anti-Cd20 Monoclonal Antibodies and Modulation in Cd20 Levels on Cell Surface: Looking to Improve Immunotherapy Response

    PubMed Central

    Singh, Vijay; Gupta, Damodar; Almasan, Alexandru

    2016-01-01

    Rituximab has been revolutionized and validated CD20 targeting monoclonal antibody. Although, it is widely used for lymphoma therapy and many patients have been benefited. However significant numbers of patients are refractory or developed resistance to current therapies due to low level of CD20 expression and/or availability on cells surface. Thus development of novel anti-CD20 mAbs with great cell killing ability and enhance CD20 levels on cell surface can potentially exploit lymphoma therapy. In this scenario, we are summarizing the recently developed mAbs against CD20 and compounds that have ability to induce CD20 expression at significant level. We also are providing information regarding combination strategy for use of radiation and anti-CD20 mAbs in vitro. However, it will need to be determined by rigorous at pre-clinical and clinic testing. We hope this review will be beneficial for current research in the area of immunotherapy or radio-immunotherapy. PMID:27413424

  3. Rituximab-induced interstitial lung disease: five case reports.

    PubMed

    Naqibullah, Matiuallah; Shaker, Saher B; Bach, Karen S; Bendstrup, Elisabeth

    2015-01-01

    Rituximab (RTX), a mouse/human chimeric anti-CD20 IgG1 monoclonal antibody has been effectively used as a single agent or in combination with chemotherapy regimen to treat lymphoma since 1997. In addition, it has been used to treat idiopathic thrombocytopenic purpura, systemic lupus erythematous, rheumatoid arthritis, and autoimmune hemolytic anemia. Recently, RTX has also been suggested for the treatment of certain connective tissue disease-related interstitial lung diseases (ILD) and hypersensitivity pneumonitis. Rare but serious pulmonary adverse reactions are reported. To raise awareness about this serious side effect of RTX treatment, as the indication for its use increases with time, we report five cases of probable RTX-ILD and discuss the current literature on this potentially lethal association. PMID:26557260

  4. Anti-JC virus antibodies in rituximab-treated patients with neuromyelitis optica spectrum disorder.

    PubMed

    Kim, Su-Hyun; Hyun, Jae-Won; Jeong, In Hye; Joung, AeRan; Yeon, Joung-Lim; Dehmel, Thomas; Adams, Ortwin; Kieseier, Bernd C; Kim, Ho Jin

    2015-03-01

    Rituximab, a chimeric monoclonal anti-CD20 antibody, has been proposed to be effective for neuromyelitis optica spectrum disorder (NMOSD). A concern for developing progressive multifocal leukoencephalopathy (PML), which is caused by John Cunningham virus (JCV), has been suggested particularly in patients treated long term with rituximab. In this study, using a modified enzyme-linked immunosorbent assay with glutathione S-transferase-tagged VP1 as the antigen, we investigated the seroprevalence of anti-JCV antibodies among 78 Korean patients with NMOSD and the change in anti-JCV antibody serostatus following long-term rituximab treatment. The overall seroprevalence of anti-JCV antibodies was 69 % prior to rituximab administration. Over a mean of 4 years of repeated treatment with rituximab, no patient developed PML. Of 24 initially seronegative patients, none converted into seropositive, whereas six (11 %) of 54 initially seropositive patients converted into seronegative. Our results might support the safety of long-term rituximab treatment in patients with NMOSD with regard to the risk of developing PML. PMID:25559683

  5. NOTE: Monte Carlo microdosimetry of 188Re- and 131I-labelled anti-CD20

    NASA Astrophysics Data System (ADS)

    Torres-García, E.; Garnica-Garza, H. M.; Ferro-Flores, G.

    2006-10-01

    The radiolabelled monoclonal antibody anti-CD20 has the property of binding to the CD20 antigen expressed on the cell surface of B-lymphocytes, thus making it a useful tool in the treatment of non-Hodgkin's lymphoma. In this work, the event-by-event Monte Carlo code NOREC is used to calculate the single-event distribution function f1(z) in the cell nucleus using the beta spectra of the 188Re and 131I radionuclides. The simulated geometry consists of two concentric spheres representing the nucleus and the cell surface embedded in a semi-infinite water medium. An isotropic point source was placed on the cell surface to simulate the binding of the anti-CD20 labelled with either 188Re or 131I. The simulations were carried out for two combinations of cell surface and nucleus radii. A method was devised that allows one to calculate the contribution of betas of energy greater than 1 MeV, which cannot be simulated by the NOREC code, to the single-event distribution function. It is shown that disregarding this contribution leads to an overestimation of the frequency-mean specific energy of the order of 9 12%. In general, the antibody radiolabelled with 131I produces single-event distribution functions that yield higher frequency-mean specific energies.

  6. Rituximab

    PubMed Central

    Storz, Ulrich

    2014-01-01

    Because drug development is not a static process, a drug’s market authorisation may change over time. In many cases, the number of indications for which a drug is approved increases. Because this facet of drug development also comes at significant costs, a corresponding patent filing strategy is required to protect these investments. The strategy as applied to rituximab, which is approved for a variety of indications, is discussed in this review. PMID:24866199

  7. Preparation & in vitro evaluation of 90Y-DOTA-rituximab

    PubMed Central

    Kameswaran, Mythili; Pandey, Usha; Dash, Ashutosh; Samuel, Grace; Venkatesh, Meera

    2016-01-01

    Background & objectives: Radioimmunotherapy is extensively being used for the treatment of non-Hodgkin's lymphoma (NHL). Use of rituximab, a chimeric anti-CD20 antibody directed against the CD20 antigen in combination with suitable beta emitters is expected to result in good treatment response by its cross-fire and bystander effects. The present work involves the conjugation of p-isothiocyanatobenzyl DOTA (p-SCN-Bn-DOTA) to rituximab, its radiolabelling with 90Y and in vitro and in vivo evaluation to determine its potential as a radioimmunotherapeutic agent. Methods: Rituximab was conjugated with p-SCN-Bn-DOTA at 1:1 antibody: DOTA molar ratio. The number of DOTA molecules linked to one molecule of rituximab was determined by radioassay and spectroscopic assay. Radiolabelling of rituximab with 90Y was carried out and its in vitro stability was evaluated. In vitro cell binding studies were carried out in Raji cells expressing CD20 antigen. Biodistribution studies were carried out in normal Swiss mice. Results: Using both radioassay and spectroscopic method, it was determined that about five molecules of DOTA were linked to rituximab. Radiolabelling of the rituximab conjugate with 90Y and subsequent purification on PD-10 column gave a product with radiochemical purity (RCP) > 98 per cent which was retained at > 90 per cent up to 72 h when stored at 37°C. In vitro cell binding experiments of 90Y-DOTA-rituximab with Raji cells exhibited specific binding of 20.7 ± 0.1 per cent with 90Y-DOTA-rituximab which reduced to 15.5 ± 0.2 per cent when incubated with cold rituximab. The equilibrium constant Kd for 90Y-DOTA-Rituximab was determined to be 3.38 nM. Radiolabelled antibody showed clearance via hepatobiliary and renal routes and activity in tibia was found to be quite low indicating in vivo stability of 90Y-DOTA-rituximab. Interpretation & conclusions: p-SCN-Bn-DOTA was conjugated with rituximab and radiolabelling with 90Y was carried out. In vitro studies carried

  8. Analysis of the effectiveness and safety of rituximab in patients with refractory lupus nephritis: a chart review.

    PubMed

    Contis, Anne; Vanquaethem, Helene; Truchetet, Marie-Elise; Couzi, Lionel; Rigothier, Claire; Richez, Christophe; Lazaro, Estibaliz; Duffau, Pierre

    2016-02-01

    Lupus nephritis is a life-threatening complication of systemic lupus erythematosus. The standard treatment for this condition, including corticosteroids and cyclophosphamide, results in a 70 % remission rate at 12 months, but it is also associated with significant morbidity. Rituximab, a chimeric anti-CD20 antibody, could be useful, given the central role of B cells in the pathogenesis of systemic lupus erythematosus. Case reports and retrospective series have reported that rituximab is effective for refractory lupus nephritis. However, the double-blind, placebo-controlled LUNAR trial failed to meet its end point. We studied clinical, biological, and immunological data on 17 patients who received rituximab as an induction treatment for refractory lupus nephritis at the University Hospital Center of Bordeaux. A complete treatment response was defined as a normal serum creatinine with inactive urinary sediment and 24-h urinary albumin <0.5 g and a partial response (PR) as a >50 % improvement in all of the renal parameters that were abnormal at baseline, with no deterioration in any parameter. Seventeen patients received rituximab as induction treatment for lupus nephritis refractory to standard treatment by cyclophosphamide. After a follow-up of 12 months, complete or partial renal remission was achieved in 53 % patients. Rituximab therapy resulted in a significant improvement in proteinuria and steroid dose tapering in all patients. Rituximab should be considered as a treatment option for refractory lupus glomerulonephritis. PMID:26762196

  9. Developmental immunotoxicology assessment of rituximab in cynomolgus monkeys.

    PubMed

    Vaidyanathan, Anu; McKeever, Kathleen; Anand, Banmeet; Eppler, Steve; Weinbauer, Gerhard F; Beyer, Joseph C

    2011-01-01

    Rituximab is a chimeric murine/human-engineered immunoglobulin (Ig) G1 anti-CD20 monoclonal antibody, selectively depleting CD20-expressing cells in peripheral blood and lymphoid tissues. As part of the rituximab registration-enabling program for rheumatoid arthritis, cynomolgus monkey embryo-fetal development and pre- and postnatal developmental toxicity studies were performed. In both studies, female cynomolgus monkeys were administered rituximab iv at doses of 0/0, 15/20, 37.5/50, and 75/100 mg/kg (loading dose/study dose) from gestation day (GD) 20 to 50 for the embryo-fetal development study and GD 20 to postpartum (pp) day 28 for the pre- and postnatal study. In the embryo-fetal development study, although maternal dosing ended during the first trimester at GD 50, placental transfer of rituximab to fetuses was demonstrated at GD 100. Consequently, fetuses demonstrated B-cell depletion in lymphoid tissues at GD 100. Repletion of B cells was demonstrated in infants in a follow-up pre- and postnatal study following fetal and neonatal exposure. In the pre- and postnatal study, despite B-cell depletion, there was no significant functional consequence on the infant's ability to mount T-cell-dependent antibody responses following vaccination or antigenic challenge. Overall, rituximab was well tolerated at maximum feasible doses up to 100 mg/kg in pregnant cynomolgus monkeys and their infants after exposure from the period of organogenesis throughout pregnancy, parturition, and postnatal development. Importantly, the preclinical data have been concordant with the clinical data in children for cases where rituximab was administered during pregnancy. PMID:20937725

  10. Rituximab: Uses in Dermatology.

    PubMed

    Gleghorn, K; Wilson, J; Wilkerson, M

    2016-09-01

    Rituximab is an anti-CD20 monoclonal antibody with considerable potential in dermatology due to an increase in off-label indications. Chronic graft-versus-host disease and pemphigus vulgaris are two of the most promising indications for off-label use of rituximab. It is a generally safe alternative that should be considered when traditional therapy with corticosteroids or immunosuppressants has failed or caused significant intolerance. Currently, rituximab is only FDA-approved for treatment of follicular and diffuse large B-cell non-Hodgkin's lymphoma, rheumatoid arthritis, chronic lymphocytic leukemia, granulomatosis with polyangiitis (formerly Wegener's granulomatosis) and microscopic polyangiitis. Herein, off-label uses of rituximab and its efficacy in the treatment of cutaneous diseases are reviewed. PMID:27603326

  11. Long-term efficacy of anti-CD20 antibodies in refractory lupus nephritis.

    PubMed

    Arce-Salinas, C Alejandro; Rodríguez-García, Felipe; Gómez-Vargas, J Iván

    2012-05-01

    Eight patients with refractory lupus nephritis received rituximab after failing standard sequential therapy and were followed for 104 weeks after the infusion. One patient died secondary to a complicated pregnancy but had stable renal function. Three patients received a re-infusion of rituximab approximately 12 months apart due to a renal flare; during the second year of follow-up, those patients progressed toward ESRD. The four remaining patients demonstrated improvements in SLEDAI score, CrCl, and proteinuria with maintenance of their standard immunosuppressive therapy and did not require a re-infusion of rituximab. Although rituximab as induction therapy for refractory lupus nephritis has been shown to have a good response, its efficacy in long-term assessments demonstrates disappointing results. PMID:21258801

  12. Targeted tumor imaging of anti-CD20-polymeric nanoparticles developed for the diagnosis of B-cell malignancies

    PubMed Central

    Capolla, Sara; Garrovo, Chiara; Zorzet, Sonia; Lorenzon, Andrea; Rampazzo, Enrico; Spretz, Ruben; Pozzato, Gabriele; Núñez, Luis; Tripodo, Claudio; Macor, Paolo; Biffi, Stefania

    2015-01-01

    The expectations of nanoparticle (NP)-based targeted drug delivery systems in cancer, when compared with convectional therapeutic methods, are greater efficacy and reduced drug side effects due to specific cellular-level interactions. However, there are conflicting literature reports on enhanced tumor accumulation of targeted NPs, which is essential for translating their applications as improved drug-delivery systems and contrast agents in cancer imaging. In this study, we characterized biodegradable NPs conjugated with an anti-CD20 antibody for in vivo imaging and drug delivery onto tumor cells. NPs’ binding specificity mediated by anti-CD20 antibody was evaluated on MEC1 cells and chronic lymphocytic leukemia patients’ cells. The whole-body distribution of untargeted NPs and anti-CD20 NPs were compared by time-domain optical imaging in a localized human/mouse model of B-cell malignancy. These studies provided evidence that NPs’ functionalization by an anti-CD20 antibody improves tumor pharmacokinetic profiles in vivo after systemic administration and increases in vivo imaging of tumor mass compared to non-targeted NPs. Together, drug delivery and imaging probe represents a promising theranostics tool for targeting B-cell malignancies. PMID:26124662

  13. Bispecific anti-CD20/22 antibodies inhibit B-cell lymphoma proliferation by a unique mechanism of action.

    PubMed

    Qu, Zhengxing; Goldenberg, David M; Cardillo, Thomas M; Shi, Victoria; Hansen, Hans J; Chang, Chien-Hsing

    2008-02-15

    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 lymphoma cells when not cross-linked, the bsAbs [eg, anti-CD20 IgG-anti-CD22 (scFv)(2)] were inhibitory without cross-linking and synergistic with B-cell antigen (BCR)-mediated inhibition. The bsAbs demonstrated higher antibody-dependent cellulary cytoxicity (ADCC) activity than the parental mAbs, but not complement-dependent cytoxicity (CDC) of the parental CD20 mAb. Cross-linking both CD20 and CD22 with the bsAbs resulted in the prominent redistribution of not only CD20 but also CD22 and BCR into lipid rafts. Surprisingly, appreciable translocation of CD22 into lipid rafts was also observed after treatment with epratuzumab. Finally, the bsAbs inhibited Daudi lymphoma transplant growth, but showed a significant advantage over the parental anti-CD20 mAb only at the highest dose tested. These results suggest that recombinantly fused, complementary, bispecific, anti-CD20/22 antibodies exhibit functional features distinct from their parental antibodies, perhaps representing new candidate therapeutic molecules. PMID:18025153

  14. Association of rituximab with graphene oxide confers direct cytotoxicity for CD20-positive lymphoma cells

    PubMed Central

    Luo, Chengke; Deng, Zhenghao; Li, Lan; Clayton, Frederic; Chen, Alexander L.; Wei, Ran; Miles, Rodney; Stephens, Deborah M.; Glenn, Martha; Wang, Xiyang; Jensen, Peter E.; Chen, Xinjian

    2016-01-01

    Non-Hodgkin lymphoma (NHL) is one of the most common hematologic malignancies among adults for which the chimeric monoclonal anti-CD20 antibody (Ab) rituximab (RTX) is used as first-line therapy. As RTX itself is not directly cytotoxic but relies on host immune effector mechanisms or chemotherapeutic agents to attack target cells, its therapeutic capacity may become limited when host effector mechanisms are compromised. Currently, refractory disease and relapse with NHL are still common, highlighting the need for novel anti-CD20 antibody strategies with superior therapeutic efficacy over current protocols. We hypothesized that making RTX directly cytotoxic might improve the therapeutic efficacy. Graphene oxide (GO) has recently emerged as a highly attractive nanomaterial for biomedical applications; and several studies have reported cytotoxic effect of GO on benign and malignant cells in vitro. Herein, we report that RTX can be stably associated with GO, and that GO-associated RTX (RTX/GO) demonstrates remarkably high avidity for CD20. Binding of GO-associated RTX to CD20-positive lymphoma cells induces CD20 capping and target cell death through an actin dependent mechanism. In vivo, GO-associated RTX, but not free RTX, quickly eliminates high-grade lymphomas in the absence of host effector mechanisms in a xenograft lymphoma mouse model. Our findings represent the first demonstration of using GO-associated antibody as effective cytotoxic therapy for human B cell malignancies in the absence of chemotherapy, and these findings could have important clinical implications. PMID:26859679

  15. Specific energy from Auger and conversion electrons of 131I, 188Re-anti-CD20 to a lymphocyte's nucleus

    NASA Astrophysics Data System (ADS)

    Torres-García, E.; Carrillo-Cazares, T. A.

    2011-01-01

    The typical radionuclides used to label anti-CD20 in the treatment of non-Hodgkin's lymphoma are 90Y, 131I, and 188Re, with the emission of beta particles, Auger electrons, and conversion electrons for the latter two. The aim of the present work was to calculate the contribution of high linear energy transfer radiation as Auger electrons (AE) and conversion electrons (CE) of 131I and 188Re-anti-CD20 to mean specific energy into the cell nucleus by Monte Carlo simulation (MCS), so as to infer therapeutic effectiveness on a dosimetric basis. MCS was used to quantify the frequency-mean specific energy into the cell nucleus, where the cell was modeled by two concentric spheres, considering two cell models. The results showed that 10% and 33% of the mean-specific energies (z¯) per disintegration imparted to the cell nucleus for both geometries are due to AE and CE; on the other hand, if the hit of AE and CE occurs, the contribution to (z¯) is about 64% and 86% for 131I and 188Re, respectively. According to the amount of specific energy from AE and CE into the cell nucleus by positive event, they can cause catastrophic effects in the nuclear DNA in the treatment of non-Hodgkin's lymphoma with 131I, 188Re-anti-CD20.

  16. Objective cerebrospinal fluid response to intraventricular rituximab in indolent CNS lymphoma

    PubMed Central

    Strowd, Roy E; Abuali, Inas A; Grossman, Stuart A

    2016-01-01

    SUMMARY Indolent CNS lymphomas (CNSLs) are rare and no guidelines exist for management. Recent literature highlights the potential for safe and tolerable intrathecal (IT) delivery of rituximab, a large anti-CD20 monoclonal antibody, for aggressive CNSL. We report a patient with relapsed indolent CNSL who failed systemic rituximab and could not tolerate IT chemotherapies, but had an objective response of 6 months duration to IT rituximab. PMID:25905905

  17. Targeted alpha-therapy using [Bi-213]anti-CD20 as novel treatment option for radio- and chemoresistant non-Hodgkin lymphoma cells

    PubMed Central

    Roscher, Mareike; Hormann, Inis; Leib, Oliver; Marx, Sebastian; Moreno, Josue; Miltner, Erich; Friesen, Claudia

    2013-01-01

    Radioimmunotherapy (RIT) is an emerging treatment option for non-Hodgkin lymphoma (NHL) producing higher overall response and complete remission rates compared with unlabelled antibodies. However, the majority of patients treated with conventional or myeloablative doses of radiolabelled antibodies relapse. The development of RIT with alpha-emitters is attractive for a variety of cancers because of the high linear energy transfer (LET) and short path length of alpha-radiation in human tissue, allowing higher tumour cell kill and lower toxicity to healthy tissues. In this study, we investigated the molecular effects of the alpha-emitter Bi-213 labelled to anti-CD20 antibodies ([Bi-213]anti-CD20) on cell cycle and cell death in sensitive and radio-/chemoresistant NHL cells. [Bi-213]anti-CD20 induced apoptosis, activated caspase-3, caspase-2 and caspase-9 and cleaved PARP specifically in CD20-expressing sensitive as well as in chemoresistant, beta-radiation resistant and gamma-radiation resistant NHL cells. CD20 negative cells were not affected by [Bi-213]anti-CD20 and unspecific antibodies labelled with Bi-213 could not kill NHL cells. Breaking radio-/chemoresistance in NHL cells using [Bi-213]anti-CD20 depends on caspase activation as demonstrated by complete inhibition of [Bi-213]anti-CD20-induced apoptosis with zVAD.fmk, a specific inhibitor of caspases activation. This suggests that deficient activation of caspases was reversed in radioresistant NHL cells using [Bi-213]anti-CD20. Activation of mitochondria, resulting in caspase-9 activation was restored and downregulation of Bcl-xL and XIAP, death-inhibiting proteins, was found after [Bi-213]anti-CD20 treatment in radio-/chemosensitive and radio-/chemoresistant NHL cells. [Bi-213]anti-CD20 seems to be a promising radioimmunoconjugate to improve therapeutic success by breaking radio- and chemoresistance selectively in CD20-expressing NHL cells via re-activating apoptotic pathways through reversing deficient

  18. The combination of milatuzumab, a humanized anti-CD74 antibody, and veltuzumab, a humanized anti-CD20 antibody, demonstrates activity in patients with relapsed and refractory B-cell non-Hodgkin lymphoma.

    PubMed

    Christian, Beth A; Poi, Ming; Jones, Jeffrey A; Porcu, Pierluigi; Maddocks, Kami; Flynn, Joseph M; Benson, Don M; Phelps, Mitch A; Wei, Lai; Byrd, John C; Wegener, William A; Goldenberg, David M; Baiocchi, Robert A; Blum, Kristie A

    2015-06-01

    As a result of the anti-tumour activity observed in vitro and in vivo with combined anti-CD20 and anti-CD74 antibodies, we initiated a phase I/II trial of veltuzumab and milatuzumab in patients with relapsed or refractory B-cell non-Hodgkin lymphoma (NHL). Patients received an induction of veltuzumab 200 mg/m(2) weekly combined with escalating doses of milatuzumab at 8, 16 and 20 mg/kg weekly for 4 weeks. Patients without disease progression could receive an extended induction with treatment on weeks 12, 20, 28 and 36. A total of 35 patients enrolled on the study. Median age was 63 years, median number of prior therapies was 3, and 63% of patients were rituximab refractory. No dose-limiting toxicities were observed in the phase I study. Related grade 3-4 toxicities included lymphopenia, leucopenia, neutropenia, anaemia, infusion reactions, hyperglycaemia, fatigue and atrial tachycardia. Median weeks of therapy was 12 and 29% of patients completed all 36 weeks of therapy. The overall response rate was 24%, median duration of response was 12 months, and responses were observed at all dose levels and in 50% of patients refractory to rituximab. Combination therapy with veltuzumab and milatuzumab demonstrated activity in a population of heavily pre-treated patients with relapsed or refractory indolent NHL. PMID:25847298

  19. Acute Respiratory Distress Syndrome and Posterior Reversible Encephalopathy Syndrome following Rituximab Therapy.

    PubMed

    Wardrope, Katrina E; Manson, Lynn; Metcalfe, Wendy; Sullivan, Eoin D O

    2016-01-01

    The anti-CD20 monoclonal antibody rituximab is associated with rare but significant adverse events, notably posterior reversible encephalopathy syndrome (PRES) and acute respiratory distress syndrome (ARDS). We report a case of concomitant ARDS and PRES developing after rituximab therapy for treatment of cryoglobulinaemic vasculitis. There are 7 reported cases of PRES complicating rituximab use. PRES onset varied from immediate to 21 days after administration. All patients recovered completely, and rituximab was reintroduced in half of the cases. The occurrence of ARDS in association with rituximab is rarer. Only 3 confirmed cases exist, and ARDS may occur as a delayed reaction. PMID:27275457

  20. Acute Respiratory Distress Syndrome and Posterior Reversible Encephalopathy Syndrome following Rituximab Therapy

    PubMed Central

    Wardrope, Katrina E.; Manson, Lynn; Metcalfe, Wendy; Sullivan, Eoin D. O

    2016-01-01

    The anti-CD20 monoclonal antibody rituximab is associated with rare but significant adverse events, notably posterior reversible encephalopathy syndrome (PRES) and acute respiratory distress syndrome (ARDS). We report a case of concomitant ARDS and PRES developing after rituximab therapy for treatment of cryoglobulinaemic vasculitis. There are 7 reported cases of PRES complicating rituximab use. PRES onset varied from immediate to 21 days after administration. All patients recovered completely, and rituximab was reintroduced in half of the cases. The occurrence of ARDS in association with rituximab is rarer. Only 3 confirmed cases exist, and ARDS may occur as a delayed reaction.

  1. Efficacy and safety of an anti-CD20 monoclonal antibody (Reditux™) for the treatment of patients with moderate to severe rheumatoid arthritis following the failure of conventional synthetic disease-modifying anti-rheumatic drugs.

    PubMed

    Bhati, Manjeet; Bandyopadhyay, Syamasis

    2016-08-01

    Rituximab (anti-CD20 monoclonal antibody) has shown to improve symptoms in rheumatoid arthritis (RA) patients with inadequate response to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs). An anti-CD20 monoclonal antibody (Reditux™) developed by Dr. Reddy's Laboratories, India, is currently approved for use both in rheumatology and oncology patients. This retrospective report evaluates the efficacy and safety data from the real-world use of Reditux™ over a 6-month period in Indian patients with RA. All consecutive moderate to severe RA patients who failed therapy with at least two DMARDs including methotrexate (MTX) for 6 months, TNFα inhibitor naive, and willing to take Reditux™ were included. They were prescribed two doses of 1 g Reditux™, at least 15 days apart, with continued stable doses of methotrexate. Efficacy and safety after 24 weeks relative to baseline was assessed using various health assessment variables. A total of 39 patients (mean age of 46 years; 67.5 % females) treated with Reditux™ were evaluated. Statistically significant differences were observed in mean changes of DAS28-CRP, DAS28-ESR, SDAI, HAQ and Patient Global Assessment scores from baseline to 24 weeks (p < 0.0001 for all). Average steroid use per week also significantly reduced at 24 weeks (p = 0.0002). There was no significant gender difference. Mean changes in SDAI, HAQ and Patient Global Assessment scores for patients on steroids were significantly different from those not on steroids (p < 0.05 for all). At 24 weeks, 97 % of patients achieved ACR20 response demonstrating the efficacy of Reditux™ treatment. The treatment was well tolerated by patients without any clinically relevant serious adverse events over 24 weeks. Though limited by number of patients and retrospective in nature, this analysis serves as a real-world evidence of efficacy and safety of Dr. Reddy's rituximab (Reditux™) in the treatment of cs

  2. Subcutaneous injections of low doses of humanized anti-CD20 veltuzumab: a phase I study in chronic lymphocytic leukemia.

    PubMed

    Kalaycio, Matt E; George Negrea, O; Allen, Steven L; Rai, Kanti R; Abbasi, Rashid M; Horne, Heather; Wegener, William A; Goldenberg, David M

    2016-01-01

    To evaluate the potential of subcutaneous (SC) injections with anti-CD20 antibody veltuzumab in chronic lymphocytic leukemia (CLL), 21 patients received 80, 160, or 320 mg injections every 2 weeks × 4 doses (n = 11) or 160 or 320 mg twice-weekly × 16 doses (n = 10). Treatment was well tolerated with only occasional, mild-moderate, transient injection reactions. Lymphocytosis decreased in all patients (maximum decrease, 5-91%), with 12 patients obtaining >50% decreases. Of 14 patients with lymphadenopathy on CT imaging, 5 (36%) achieved 14-61% reductions (sum of perpendicular diameters). By NCI-WG criteria, two patients achieved partial responses (10%). SC veltuzumab appeared active in all dose groups, with no obvious exposure-response relationship, despite cumulative doses ranging from 320-5120 mg. Overall median progression-free survival was 7.7 months; three patients remained progression-free >1 year (2 ongoing at 2-year study completion). These data suggest further studies of SC veltuzumab in CLL are warranted. PMID:26389849

  3. Expression of bioactive anti-CD20 antibody fragments and induction of ER stress response in Arabidopsis seeds.

    PubMed

    Wang, Dezhong; Ma, Jisheng; Sun, Difei; Li, Haiyan; Jiang, Chao; Li, Xiaokun

    2015-08-01

    Seed-based expression system is an attractive platform for the production of recombinant proteins in molecular farming. Despite the many advantages of molecular farming, little is known about the effect of the different subcellular accumulation of recombinant proteins on the endoplasmic reticulum (ER) quality control system in host plants. In this study, we analyzed the expression of anti-CD20 antibody fragments in seeds of Arabidopsis thaliana (ecotype Columbia) and corresponding glycosylation mutants, and evaluated the influence of three different signal sequences on the expression levels of scFv-Fc of C2B8. The highest protein accumulation level, with a maximum of 6.12 % total soluble proteins, was observed upon fusing proteins to the signal peptide of Arabidopsis seed storage albumin 2. The ER stress responses in developing seeds at 13 days post-anthesis were also compared across different transgenic lines under normal and heat shock conditions. Based on the gene expression profiles of ER stress transducers, our results suggest that accumulation of antibody fragments in the ER exerts more stress on ER homeostasis. In addition, quantitative PCR results also implicate enhanced activation of ER-associated degradation in transgenic lines. Last but not the least, we also demonstrate the anti-tumor potency of plant-derived proteins by showing the anti-tumor activity of purified scFv-Fc proteins against Daudi cells. Together, our data implies that better understanding of the interaction between exogenous protein production and the cellular quality control system of the host plant is necessary for the development of an optimal expression strategy that will be especially beneficial to commercial protein manufacturing. PMID:25957150

  4. Comparative efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    DOE PAGESBeta

    Frost, Sofia H. L.; Frayo, Shani L.; Miller, Brian W.; Orozco, Johnnie J.; Booth, Garrett C.; Hylarides, Mark D.; Lin, Yukang; Green, Damian J.; Gopal, Ajay K.; Pagel, John M.; et al

    2015-03-18

    Purpose Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targetingmore » either 90Y or 177Lu to human B-cell lymphoma xenografts in mice. Methods Parallel experiments evaluating the biodistribution, imaging, dosimetry, therapeutic efficacy, and toxicity were performed in female athymic nude mice bearing either Ramos (Burkitt lymphoma) or Granta (mantle cell lymphoma) xenografts, utilizing an anti-CD20 antibodystreptavidin conjugate (1F5-SA) and an 90Y- or 177Lu-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-biotin second step reagent. Results The two radionuclides displayed comparable biodistributions in tumors and normal organs; however, the absorbed radiation dose delivered to tumor was more than twice as high for 90Y (1.3 Gy/MBq) as for 177Lu (0.6 Gy/MBq). More importantly, therapy with 90Y-DOTAbiotin was dramatically more effective than with 177Lu-DOTA-biotin, with 100% of Ramos xenograft-bearing mice cured with 37 MBq 90Y, whereas 0% were cured using identical amounts of 177Lu-DOTA-biotin. Similar results were observed in mice bearing Granta xenografts, with 80% of the mice cured with 90Y-PRIT and 0% cured with 177Lu-PRIT. Toxicities were comparable with both isotopes. Conclusion 90Y was therapeutically superior to 177Lu for streptavidin-biotin PRIT

  5. Comparative Efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    PubMed Central

    Frost, Sofia H. L.; Frayo, Shani L.; Miller, Brian W.; Orozco, Johnnie J.; Booth, Garrett C.; Hylarides, Mark D.; Lin, Yukang; Green, Damian J.; Gopal, Ajay K.; Pagel, John M.; Bäck, Tom A.; Fisher, Darrell R.; Press, Oliver W.

    2015-01-01

    Purpose Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice. Methods Parallel experiments evaluating the biodistribution, imaging, dosimetry, therapeutic efficacy, and toxicity were performed in female athymic nude mice bearing either Ramos (Burkitt lymphoma) or Granta (mantle cell lymphoma) xenografts, utilizing an anti-CD20 antibody-streptavidin conjugate (1F5-SA) and an 90Y- or 177Lu-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-biotin second step reagent. Results The two radionuclides displayed comparable biodistributions in tumors and normal organs; however, the absorbed radiation dose delivered to tumor was more than twice as high for 90Y (1.3 Gy/MBq) as for 177Lu (0.6 Gy/MBq). More importantly, therapy with 90Y-DOTA-biotin was dramatically more effective than with 177Lu-DOTA-biotin, with 100% of Ramos xenograft-bearing mice cured with 37 MBq 90Y, whereas 0% were cured using identical amounts of 177Lu-DOTA-biotin. Similar results were observed in mice bearing Granta xenografts, with 80% of the mice cured with 90Y-PRIT and 0% cured with 177Lu-PRIT. Toxicities were comparable with both isotopes. Conclusion 90Y was therapeutically superior to 177Lu for streptavidin-biotin PRIT approaches in

  6. [Recurrent infections in an ITP patient treated with rituximab].

    PubMed

    Rosenberg-Bezalel, Shira; Asher, Ilan; Sthoeger, Zev

    2012-11-01

    Common variable immunodeficiency (CVID) is a heterogeneous group of disorders characterized by hypogammaglobulinemia and recurrent infections. Various mechanisms have been implied in the disease pathophysiology. Patients with CVID are at increased risk of developing ITP (Immune Thrombocytopenia Purpura) and/ or AIHA (Autoimmune Haemolytic Anemia). Rituximab, a humanized anti-CD20 monoclonal antibody, is increasingly being used for autoimmune cytopenias including ITP and AIHA. This is a case history of a patient treated with Rituximab due to refractory ITP. A year after completion of therapy the patient started suffering from an increased frequency of infections. Six years after treatment with Rituximab the patient was diagnosed with CVID and IVIG replacement treatment was started. The main possibilities that this patient presents include aggravation of CVID, first presented as ITP, after Rituximab treatment versus CVID secondary to Rituximab treatment. PMID:23367730

  7. Radiolabelling rituximab with (99m)Tc in three steps procedure.

    PubMed

    Fontan, Charlotte; Bezombes, Christine; Salabert, Anne Sophie; Costes, Julien; Lopez, Raphael; Fournie, Jean-Jacques; Avet-Loiseau, Hervé; Coulais, Yvon; Payoux, Pierre; Tafani, Mathieu

    2015-06-15

    Lymphomas are the most frequent haematological malignancy. In non-Hodgkin's lymphomas (NHL), more than 90% of tumor cells express the cluster of differentiation (CD) 20 antigen. At the end of frontline therapy, the evaluation of remission is based on computed tomography (CT) and positron emission tomography coupled with computer tomography (PET/CT) with [(18)F]-fluorodeoxyglucose ([(18)F]FDG). Unfortunately, these techniques are not specific and cannot distinguish residual active tumor from inflammation. The aim of this study was to develop a specific radiotracer of NHL CD 20+ cells for clinical applications. The radiolabelling technique presented, based on the use of tricarbonyl compound, does not include an antibody reduction because this step could damage the protein. Actually, rituximab, an anti-CD 20 chimeric antibody used for the treatment of these NHL, was radiolabelled with Isolink® (99m)Tc-tricarbonyl compound in a three-step procedure without using a specific antibody reducer. Radiolabelling yield was greater than 97%. In vitro experiments showed a conservation of antibody integrity. In vivo experiments using Single-photon emission computed tomography/CT showed significant tumor targeting 24 h after injection of the radiotracer. It was consequently possible to develop an immunoradiolabelling method to specifically detect the residual disease. As this procedure is fast, reproducible and gentle, it will be possible to comply with Good Manufacturing Practices. PMID:26017396

  8. Specific Conjugation of the Hinge Region for Homogeneous Preparation of Antibody Fragment-Drug Conjugate: A Case Study for Doxorubicin-PEG-anti-CD20 Fab' Synthesis.

    PubMed

    Zhou, Zhan; Zhang, Jing; Zhang, Yan; Ma, Guanghui; Su, Zhiguo

    2016-01-20

    Conventional preparation strategies for antibody-drug conjugates (ADCs) result in heterogeneous products with various molecular sizes and species. In this study, we developed a homogeneous preparation strategy by site-specific conjugation of the anticancer drug with an antibody fragment. The model drug doxorubicin (DOX) was coupled to the Fab' fragment of anti-CD20 IgG at its permissive sites through a heterotelechelic PEG linker, generating an antibody fragment-drug conjugate (AFDC). Anti-CD20 IgG was digested and reduced specifically with β-mercaptoethylamine to generate the Fab' fragment with two free mercapto groups in its hinge region. Meanwhile, DOX was conjugated with α-succinimidylsuccinate ω-maleimide polyethylene glycol (NHS-PEG-MAL) to form MAL-PEG-DOX, which was subsequently linked to the free mercapto containing Fab' fragment to form a Fab'-PEG-DOX conjugate. The dual site-specific bioconjugation was achieved through the combination of highly selective reduction of IgG and introduction of heterotelechelic PEG linker. The resulting AFDC provides an utterly homogeneous product, with a definite ratio of one fragment to two drugs. Laser confocal microscopy and cell ELISA revealed that the AFDC could accumulate in the antigen-positive Daudi tumor cell. In addition, the Fab'-PEG-DOX retained appreciable targeting ability and improved antitumor activity, demonstrating an excellent therapeutic effect on the lymphoma mice model for better cure rate and significantly reduced side effects. PMID:26700095

  9. Astatine-211 conjugated to an anti-CD20 monoclonal antibody eradicates disseminated B-cell lymphoma in a mouse model

    SciTech Connect

    Green, Damian J.; Shadman, Mazyar; Jones, Jon C.; Frayo, Shani; Kenoyer, Aimee L.; Hylarides, Mark; Hamlin, Donald K.; Wilbur, D. Scott; Balkan, Ethan R.; Lin, Yukang; Miller, Brian W.; Frost, Sophia; Gopal, Ajay K.; Orozco, Johnnie J.; Gooley, Ted; Laird, Kelley L.; Till, B. G.; Back, Tom; Sandmaier, B. M.; Pagel, John M.; Press, Oliver W.

    2015-03-26

    Alpha emitting radionuclides release a large amount of energy within a few cell diameters and may be particularly effective for radioimmunotherapy targeting minimal residual disease (MRD) conditions in which micrometastatic disease satellites are broadly distributed. To evaluate this hypothesis, 211At conjugated 1F5 mAb (anti-CD20) was studied in both bulky lymphoma tumor xenograft and MRD animal models. Superior treatment responses to 211At conjugated 1F5 mAb were evident in the MRD setting. Lymphoma xenograft tumor bearing animals treated with doses of up to 48µCi of anti-CD20 211At-decaborate [211At-B10-1F5] experienced modest responses (0% cures but 2-3-fold prolongation of survival compared to negative controls). In contrast, 70% of animals in the MRD lymphoma model demonstrated complete eradication of disease when treated with 211At-B10-1F5 at a radiation dose that was less than one-third (15 µCi) of the highest dose given to xenograft animals. Tumor progression among untreated control animals in both models was uniformly lethal. After 130 days, no significant renal or hepatic toxicity is observed in the cured animals receiving 15 µCi of 211At-B10-1F5. These findings suggest that in a MRD lymphoma model, where isolated cells and tumor microclusters prevail, α-emitters may be uniquely efficacious.

  10. Anti-CD20 antibody promotes cancer escape via enrichment of tumor-evoked regulatory B cells expressing low levels of CD20 and CD137L.

    PubMed

    Bodogai, Monica; Lee Chang, Catalina; Wejksza, Katarzyna; Lai, Jinping; Merino, Maria; Wersto, Robert P; Gress, Ronald E; Chan, Andrew C; Hesdorffer, Charles; Biragyn, Arya

    2013-04-01

    The possible therapeutic benefits of B-cell depletion in combating tumoral immune escape have been debated. In support of this concept, metastasis of highly aggressive 4T1 breast cancer cells in mice can be abrogated by inactivation of tumor-evoked regulatory B cells (tBreg). Here, we report the unexpected finding that B-cell depletion by CD20 antibody will greatly enhance cancer progression and metastasis. Both murine and human tBregs express low levels of CD20 and, as such, anti-CD20 mostly enriches for these cells. In the 4T1 model of murine breast cancer, this effect of enriching for tBregs suggests that B-cell depletion by anti-CD20 may not be beneficial at all in some cancers. In contrast, we show that in vivo-targeted stimulation of B cells with CXCL13-coupled CpG oligonucleotides (CpG-ODN) can block cancer metastasis by inhibiting CD20(Low) tBregs. Mechanistic investigations suggested that CpG-ODN upregulates low surface levels of 4-1BBL on tBregs to elicit granzyme B-expressing cytolytic CD8(+) T cells, offering some explanative power for the effect. These findings underscore the immunotherapeutic importance of tBreg inactivation as a strategy to enhance cancer therapy by targeting both the regulatory and activating arms of the immune system in vivo. PMID:23365136

  11. Astatine-211 conjugated to an anti-CD20 monoclonal antibody eradicates disseminated B-cell lymphoma in a mouse model

    PubMed Central

    Shadman, Mazyar; Jones, Jon C.; Frayo, Shani L.; Kenoyer, Aimee L.; Hylarides, Mark D.; Hamlin, Donald K.; Wilbur, D. Scott; Balkan, Ethan R.; Lin, Yukang; Miller, Brian W.; Frost, Sofia H. L.; Gopal, Ajay K.; Orozco, Johnnie J.; Gooley, Theodore A.; Laird, Kelly L.; Till, Brian G.; Bäck, Tom; Sandmaier, Brenda M.; Pagel, John M.; Press, Oliver W.

    2015-01-01

    α-Emitting radionuclides deposit a large amount of energy within a few cell diameters and may be particularly effective for radioimmunotherapy targeting minimal residual disease (MRD). To evaluate this hypothesis, 211At-labeled 1F5 monoclonal antibody (mAb) (anti-CD20) was studied in both bulky lymphoma tumor xenograft and MRD animal models. Superior treatment responses to 211At-labeled 1F5 mAb were evident in the MRD setting. Lymphoma xenograft tumor-bearing animals treated with doses of up to 48 µCi of 211At-labeled anti-CD20 mAb ([211At]1F5-B10) experienced modest responses (0% cures but two- to threefold prolongation of survival compared with negative controls). In contrast, 70% of animals in the MRD lymphoma model demonstrated complete eradication of disease when treated with 211At-B10-1F5 at a radiation dose that was less than one-third (15 µCi) of the highest dose given to xenograft animals. Tumor progression among untreated control animals in both models was uniformly lethal. After 130 days, no significant renal or hepatic toxicity was observed in the cured animals receiving 15 µCi of [211At]1F5-B10. These findings suggest that α-emitters are highly efficacious in MRD settings, where isolated cells and small tumor clusters prevail. PMID:25628467

  12. Astatine-211 conjugated to an anti-CD20 monoclonal antibody eradicates disseminated B-cell lymphoma in a mouse model.

    PubMed

    Green, Damian J; Shadman, Mazyar; Jones, Jon C; Frayo, Shani L; Kenoyer, Aimee L; Hylarides, Mark D; Hamlin, Donald K; Wilbur, D Scott; Balkan, Ethan R; Lin, Yukang; Miller, Brian W; Frost, Sofia H L; Gopal, Ajay K; Orozco, Johnnie J; Gooley, Theodore A; Laird, Kelly L; Till, Brian G; Bäck, Tom; Sandmaier, Brenda M; Pagel, John M; Press, Oliver W

    2015-03-26

    α-Emitting radionuclides deposit a large amount of energy within a few cell diameters and may be particularly effective for radioimmunotherapy targeting minimal residual disease (MRD). To evaluate this hypothesis, (211)At-labeled 1F5 monoclonal antibody (mAb) (anti-CD20) was studied in both bulky lymphoma tumor xenograft and MRD animal models. Superior treatment responses to (211)At-labeled 1F5 mAb were evident in the MRD setting. Lymphoma xenograft tumor-bearing animals treated with doses of up to 48 µCi of (211)At-labeled anti-CD20 mAb ([(211)At]1F5-B10) experienced modest responses (0% cures but two- to threefold prolongation of survival compared with negative controls). In contrast, 70% of animals in the MRD lymphoma model demonstrated complete eradication of disease when treated with (211)At-B10-1F5 at a radiation dose that was less than one-third (15 µCi) of the highest dose given to xenograft animals. Tumor progression among untreated control animals in both models was uniformly lethal. After 130 days, no significant renal or hepatic toxicity was observed in the cured animals receiving 15 µCi of [(211)At]1F5-B10. These findings suggest that α-emitters are highly efficacious in MRD settings, where isolated cells and small tumor clusters prevail. PMID:25628467

  13. Membrane microdomain sphingolipids are required for anti-CD20-induced death of chronic lymphocytic leukemia B cells

    PubMed Central

    Hammadi, Mariam; Youinou, Pierre; Tempescul, Adrian; Tobón, Gabriel; Berthou, Christian; Bordron, Anne; Pers, Jacques-Olivier

    2012-01-01

    Background Chronic lymphocytic leukemia remains incurable, despite the addition of rituximab to chemotherapy as an available means of treatment. The resistance of certain patients to this monoclonal antibody prompted us to set up in vitro studies of another CD20-specific monoclonal antibody, B1 (later termed tositumomab). We hypothesized that the membrane lipid organization of leukemic B cells might be instrumental in the cells’ sensitivity to the B1 monoclonal antibody. Design and Methods B lymphocytes from 36 patients with chronic lymphocytic leukemia and 13 patients with non-Hodgkin’s lymphoma were investigated for B1-triggered cell death. Membrane components, such as sphingomyelin and ganglioside M1, were investigated by flow cytometry, immunofluorescence and co-immunoprecipitation, together with the Csk-binding protein. Results Chronic lymphocytic leukemia patients segregated into two groups: B cells from one group were sensitive to B1, whereas those from the second group were not. Further results ascribed the resistance of these latter cases to a defective recruitment of Csk-binding protein, resulting in a lack of sphingomyelin and ganglioside M1 at the outer leaflet of the plasma membrane of their malignant B cells. Sphingolipids were indeed retained in the cytoplasm, because of lowered activity of P-glycoprotein. Supporting this mechanism, rifampicin, an inducer of P-glycoprotein, improved the activity of this transmembrane efflux pump, normalized the quantity of sphingomyelin within the membrane, and thereby restored the efficacy of the B1 monoclonal antibody in the formerly B1-resistant cases of chronic lymphocytic leukemia. Conclusions The lipid organization of membranes of B cells from patients with chronic lymphocytic leukemia differs from one patient to another. In practice, given the relevance of the membrane lipid distribution to the efficacy of biotherapies, this observation is of potential importance. PMID:22058197

  14. Anti-CD20 Immunoglobulin G Radiolabeling with a 99mTc-Tricarbonyl Core: In Vitro and In Vivo Evaluations

    PubMed Central

    Carpenet, Hélène; Cuvillier, Armelle; Monteil, Jacques; Quelven, Isabelle

    2015-01-01

    In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig) appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc), an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate—polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig’s immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT). Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%). 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C) and in serum (37°C), even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is “antibody safe” and

  15. Anti-CD20 Immunoglobulin G Radiolabeling with a 99mTc-Tricarbonyl Core: In Vitro and In Vivo Evaluations.

    PubMed

    Carpenet, Hélène; Cuvillier, Armelle; Monteil, Jacques; Quelven, Isabelle

    2015-01-01

    In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig) appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc), an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig's immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT). Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%). 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C) and in serum (37°C), even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is "antibody safe" and preserves

  16. Fatal haemoptysis in a case of lymphomatoid granulomatosis treated with rituximab.

    PubMed

    Jaffre, S; Jardin, F; Dominique, S; Duet, E; Hubscher, Ph; Genevois, A; Corne, F; Bota, S; Nouvet, G; Thiberville, L

    2006-03-01

    Lymphomatoid granulomatosis is a rare angiocentric and angiodestructive disease, which commonly involves the lungs but also the brain, kidneys, liver and skin. This report describes the case of a 33-yr-old female with an aggressive form of lymphoid granulomatosis treated with an anti-CD20 antibody. Dramatic radiological improvement was seen at the fourth week. However, the patient died at home 1 month after the last rituximab administration from a massive haemoptysis. PMID:16507866

  17. Hexavalent bispecific antibodies represent a new class of anticancer therapeutics: 1. Properties of anti-CD20/CD22 antibodies in lymphoma

    PubMed Central

    Cardillo, Thomas M.; Stein, Rhona; Chang, Chien-Hsing

    2009-01-01

    The dock and lock (DNL) method is a new technology for generating multivalent antibodies. Here, we report in vitro and in vivo characterizations of 20-22 and 22-20, a pair of humanized hexavalent anti-CD20/22 bispecific antibodies (bsAbs) derived from veltuzumab (v-mab) and epratuzumab (e-mab). The 22-20 was made by site-specific conjugation of e-mab to 4 Fabs of v-mab; 20-22 is of the opposite configuration, composing v-mab and 4 Fabs of e-mab. Each bsAb translocates both CD22 and CD20 into lipid rafts, induces apoptosis and growth inhibition without second-antibody crosslinking, and is significantly more potent in killing lymphoma cells in vitro than their parental antibodies. Although both bsAbs triggered antibody-dependent cellular toxicity, neither displayed complement-dependent cytotoxicity. Intriguingly, 22-20 and 20-22 killed human lymphoma cells in preference to normal B cells ex vivo, whereas the parental v-mab depleted malignant and normal B cells equally. In vivo studies in Daudi tumors revealed 20-22, despite having a shorter serum half-life, had antitumor efficacy comparable with equimolar v-mab; 22-20 was less potent than 20-22 but more effective than e-mab and control bsAbs. These results indicate multiple advantages of hexavalent anti-CD20/22 bsAbs over the individual parental antibodies and suggest that these may represent a new class of cancer therapeutics. PMID:19372261

  18. Hexavalent bispecific antibodies represent a new class of anticancer therapeutics: 1. Properties of anti-CD20/CD22 antibodies in lymphoma.

    PubMed

    Rossi, Edmund A; Goldenberg, David M; Cardillo, Thomas M; Stein, Rhona; Chang, Chien-Hsing

    2009-06-11

    The dock and lock (DNL) method is a new technology for generating multivalent antibodies. Here, we report in vitro and in vivo characterizations of 20-22 and 22-20, a pair of humanized hexavalent anti-CD20/22 bispecific antibodies (bsAbs) derived from veltuzumab (v-mab) and epratuzumab (e-mab). The 22-20 was made by site-specific conjugation of e-mab to 4 Fabs of v-mab; 20-22 is of the opposite configuration, composing v-mab and 4 Fabs of e-mab. Each bsAb translocates both CD22 and CD20 into lipid rafts, induces apoptosis and growth inhibition without second-antibody crosslinking, and is significantly more potent in killing lymphoma cells in vitro than their parental antibodies. Although both bsAbs triggered antibody-dependent cellular toxicity, neither displayed complement-dependent cytotoxicity. Intriguingly, 22-20 and 20-22 killed human lymphoma cells in preference to normal B cells ex vivo, whereas the parental v-mab depleted malignant and normal B cells equally. In vivo studies in Daudi tumors revealed 20-22, despite having a shorter serum half-life, had antitumor efficacy comparable with equimolar v-mab; 22-20 was less potent than 20-22 but more effective than e-mab and control bsAbs. These results indicate multiple advantages of hexavalent anti-CD20/22 bsAbs over the individual parental antibodies and suggest that these may represent a new class of cancer therapeutics. PMID:19372261

  19. Role of Rituximab and Rituximab Biosimilars in Diffuse Large B-Cell Lymphoma.

    PubMed

    Coleman, Morton; Lammers, Philip E; Ciceri, Fabio; Jacobs, Ira A

    2016-04-01

    Diffuse large B-cell lymphoma (DLBCL), an aggressive non-Hodgkin lymphoma (NHL), is the most-common subtype of NHL. DLBCL can be classified into at least 3 major immunologically distinct types, which contributes to considerable variation in disease prognosis and response to treatment. DLBCL potentially is curable, even when diagnosed at advanced stages. The current standard of care for most patients with untreated or relapsed/refractory DLBCL is chemoimmunotherapy containing rituximab, an anti-CD20 monoclonal antibody. With advanced understanding of the molecular mechanisms involved in the pathogenesis of DLBCL and specific signaling pathways that are activated in different subtypes, potential new therapeutic targets have been identified, some of which are at the late stages of clinical development. This review summarizes the critical role of rituximab in the current standard of care treatment for DLBCL and discusses why rituximab is likely to remain an important component of treatment options for DLBCL in the foreseeable future. In addition, current and emerging therapeutic agents, including potential benefits of rituximab biosimilars, for patients with DLBCL are discussed. The advent of rituximab biosimilars may facilitate accessibility of rituximab-based chemotherapies to patients with DLBCL and has potential cost-saving benefits for healthcare systems globally. PMID:26906106

  20. Acquired Hemophilia A Successfully Treated with Rituximab

    PubMed Central

    D’Arena, Giovanni; Grandone, Elvira; Di Minno, Matteo Nicola Dario; Musto, Pellegrino; Di Minno, Giovanni

    2015-01-01

    Acquired hemophilia A (AHA) is a rare bleeding disorder due to the development of specific autoantibodies against factor VIII. The anti-CD20 monoclonal antibody Rituximab has been proven to be effective in obtaining a long-term suppression of inhibitors of AHA, besides other immunosuppressive standard treatments. Here we describe a case of idiopathic AHA in a 60-year old man successfully treated with rituximab. He showed a complete clinical response with a normalization of clotting parameters after 5 weekly courses of rituximab given at a dose of 375 mg/sqm., but after stopping rituximab, an initial worsening of coagulation parameters induced the addition of 3 further courses. At present, the patient is in complete clinical and hematological remission after 200 days. This case confirms that Rituximab may be a safe and useful tool to treat AHA and, a prolonged administration can overcome the initial resistance. However, the precise position of this drug in the therapeutic strategy (first or second-line, alone or in combination with other drugs) remains to be established and warrants further investigation. PMID:25745551

  1. Dual-targeting immunotherapy of lymphoma: potent cytotoxicity of anti-CD20/CD74 bispecific antibodies in mantle cell and other lymphomas.

    PubMed

    Gupta, Pankaj; Goldenberg, David M; Rossi, Edmund A; Cardillo, Thomas M; Byrd, John C; Muthusamy, Natarajan; Furman, Richard R; Chang, Chien-Hsing

    2012-04-19

    We describe the use of novel bispecific hexavalent Abs (HexAbs) to enhance anticancer immunotherapy. Two bispecific HexAbs [IgG-(Fab)(4) constructed from veltuzumab (anti-CD20 IgG) and milatuzumab (anti-CD74 IgG)] show enhanced cytotoxicity in mantle cell lymphoma (MCL) and other lymphoma/leukemia cell lines, as well as patient tumor samples, without a crosslinking Ab, compared with their parental mAb counterparts, alone or in combination. The bispecific HexAbs have different properties from and are more potent than their parental mAbs in vitro. The juxtaposition of CD20 and CD74 on MCL cells by the HexAbs resulted in homotypic adhesion and triggered intracellular changes that include loss of mitochondrial transmembrane potential, production of reactive oxygen species, rapid and sustained phosphorylation of ERKs and JNK, down-regulation of pAkt and Bcl-xL, actin reorganization, and lysosomal membrane permeabilization, culminating in cell death. They also displayed different potencies in depleting lymphoma cells and normal B cells from whole blood ex vivo and significantly extended the survival of nude mice bearing MCL xenografts in a dose-dependent manner, thus indicating stability and antitumor activity in vivo. Such bispecific HexAbs may constitute a new class of therapeutic agents for improved cancer immunotherapy, as shown here for MCL and other CD20(+)/CD74(+) malignancies. PMID:22271448

  2. Antitumor effects of an engineered and energized fusion protein consisting of an anti-CD20 scFv fragment and lidamycin.

    PubMed

    Fang, Hong; Miao, Qingfang; Zhang, Shenghua; Cheng, Xin; Xiong, Dongsheng; Zhen, Yongsu

    2011-03-01

    Antibody-based fusion proteins are the next generation of antibody therapies for cancer and other diseases. CD20 antigen, which is overexpressed on cell membranes in nearly 95% of cases of B-cell Non-Hodgkin's Lymphoma, is an attractive target for the therapy of B-lymphoid malignancies. Lidamycin (LDM) is a potent enediyne-containing antitumor antibiotic that now has entered phase II clinical trials. In this study, we prepared an engineered fusion protein, scFv-LDP, consisting of an anti-CD20 scFv fragment and the apoprotein LDP of LDM using DNA recombination. After purification and refolding, scFv-LDP was found to bind specifically to CD20-positive lymphoma cells using ELISA and indirect immunofluorescent cytochemical staining assays. The energized fusion protein scFv-LDP-AE was obtained using molecular reconstitution of the active chromophore AE of LDM and scFv-LDP. MTT assay revealed potent cytotoxicity of scFv-LDP-AE to CD20-positive Raji and Daudi cells, with IC(50) values of 1.21×10(-11) and 6.24×10(-11) mol L(-1), respectively. An in vivo subcutaneous xenograft model of CD20-positive B cell lymphoma in BALB/c (nu/nu) mice was also utilized. Drugs were given intravenously on day 14 and 21 after tumor transplantation. In terms of maximal tolerated doses, scFv-LDP-AE at 0.3 mg kg(-1) suppressed tumor growth by 79.3%, and LDM at 0.05 mg kg(-1) by 68.6% (P<0.05). Results suggested scFv-LDP-AE could be a potential candidate for tumor-targeting therapy. PMID:21416325

  3. Radioimmunotherapy Combined with Maintenance Anti-CD20 Antibody May Trigger Long-Term Protective T Cell Immunity in Follicular Lymphoma Patients

    PubMed Central

    Buchegger, Franz; Larson, Steven M.; Mach, Jean-Pierre; Dietrich, Pierre-Yves; Cairoli, Anne; Prior, John O.; Romero, Pedro; Speiser, Daniel E.

    2013-01-01

    Growing evidence suggests that the patient's immune response may play a major role in the long-term efficacy of antibody therapies of follicular lymphoma (FL). Particular long-lasting recurrence free survivals have been observed after first line, single agent rituximab or after radioimmunotherapy (RIT). Rituximab maintenance, furthermore, has a major efficacy in prolonging recurrence free survival after chemotherapy. On the other hand, RIT as a single step treatment showed a remarkable capacity to induce complete and partial remissions when applied in recurrence and as initial treatment of FL or given for consolidation. These clinical results strongly suggest that RIT combined with rituximab maintenance could stabilize the high percentages of patients with CR and PR induced by RIT. While the precise mechanisms of the long-term efficacy of these 2 treatments are not elucidated, different observations suggest that the patient's T cell immune response could be decisive. With this review, we discuss the potential role of the patient's immune system under rituximab and RIT and argue that the T cell immunity might be particularly promoted when combining the 2 antibody treatments in the early therapy of FL. PMID:24371449

  4. CD19 chimeric antigen receptor (CD19 CAR)-redirected adoptive T-cell immunotherapy for the treatment of relapsed or refractory B-cell Non-Hodgkin’s Lymphomas

    PubMed Central

    Onea, Alexandra S; Jazirehi, Ali R

    2016-01-01

    Recovery rates for B-cell Non-Hodgkin’s Lymphoma (NHL) are up to 70% with current standard-of-care treatments including rituximab (chimeric anti-CD20 monoclonal antibody) in combination with chemotherapy (R-CHOP). However, patients who do not respond to first-line treatment or develop resistance have a very poor prognosis. This signifies the need for the development of an optimal treatment approach for relapsed/refractory B-NHL. Novel CD19- chimeric antigen receptor (CAR) T-cell redirected immunotherapy is an attractive option for this subset of patients. Anti-CD19 CAR T-cell therapy has already had remarkable efficacy in various leukemias as well as encouraging outcomes in phase I clinical trials of relapsed/refractory NHL. In going forward with additional clinical trials, complementary treatments that may circumvent potential resistance mechanisms should be used alongside anti-CD19 T-cells in order to prevent relapse with resistant strains of disease. Some such supplementary tactics include conditioning with lymphodepletion agents, sensitizing with kinase inhibitors and Bcl-2 inhibitors, enhancing function with multispecific CAR T-cells and CD40 ligand-expressing CAR T-cells, and safeguarding with lymphoma stem cell-targeted treatments. A therapy regimen involving anti-CD19 CAR T-cells and one or more auxiliary treatments could dramatically improve prognoses for patients with relapsed/refractory B-cell NHL. This approach has the potential to revolutionize B-NHL salvage therapy in much the same way rituximab did for first-line treatments. PMID:27186412

  5. Comparative efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    SciTech Connect

    Frost, Sofia H. L.; Frayo, Shani L.; Miller, Brian W.; Orozco, Johnnie J.; Booth, Garrett C.; Hylarides, Mark D.; Lin, Yukang; Green, Damian J.; Gopal, Ajay K.; Pagel, John M.; Bäck, Tom A.; Fisher, Darrell R.; Press, Oliver W.; Afrin, Farhat

    2015-03-18

    Purpose Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice. Methods Parallel experiments evaluating the biodistribution, imaging, dosimetry, therapeutic efficacy, and toxicity were performed in female athymic nude mice bearing either Ramos (Burkitt lymphoma) or Granta (mantle cell lymphoma) xenografts, utilizing an anti-CD20 antibodystreptavidin conjugate (1F5-SA) and an 90Y- or 177Lu-labeled 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-biotin second step reagent. Results The two radionuclides displayed comparable biodistributions in tumors and normal organs; however, the absorbed radiation dose delivered to tumor was more than twice as high for 90Y (1.3 Gy/MBq) as for 177Lu (0.6 Gy/MBq). More importantly, therapy with 90Y-DOTAbiotin was dramatically more effective than with 177Lu-DOTA-biotin, with 100% of Ramos xenograft-bearing mice cured with 37 MBq 90Y, whereas 0% were cured using identical amounts of 177Lu-DOTA-biotin. Similar results were observed in mice bearing Granta xenografts, with 80% of the mice cured with 90Y-PRIT and 0

  6. Synergistic and persistent effect of T-cell immunotherapy with anti-CD19 or anti-CD38 chimeric receptor in conjunction with rituximab on B-cell non-Hodgkin lymphoma.

    PubMed

    Mihara, Keichiro; Yanagihara, Kazuyoshi; Takigahira, Misato; Kitanaka, Akira; Imai, Chihaya; Bhattacharyya, Joyeeta; Kubo, Takanori; Takei, Yoshifumi; Yasunaga, Shin'ichiro; Takihara, Yoshihiro; Kimura, Akiro

    2010-10-01

    Using artificial receptors, it is possible to redirect the specificity of immune cells to tumour-associated antigens, which is expected to provide a useful strategy for cancer immunotherapy. Given that B-cell non-Hodgkin lymphoma (B-NHL) cells invariably express CD19 and CD38, these antigens may be suitable molecular candidates for such immunotherapy. We transduced human peripheral T cells or a T-cell line with either anti-CD19-chimeric receptor (CAR) or anti-CD38-CAR, which contained an anti-CD19 or anti-CD38 antibody-derived single-chain variable domain respectively. Retroviral transduction led to anti-CD19-CAR or anti-CD38-CAR expression in T cells with high efficiency (>60%). The T cell line, Hut78, when transduced with anti-CD19-CAR or anti-CD38-CAR, exerted strong cytotoxicity against the B-NHL cell lines, HT and RL, and lymphoma cells isolated from patients. Interestingly, use of both CARs had an additive cytotoxic effect on HT cells in vitro. In conjunction with rituximab, human peripheral T cells expressing either anti-CD19-CAR or anti-CD38-CAR enhanced cytotoxicity against HT-luciferase cells in xenografted mice. Moreover, the synergistic tumour-suppressing activity was persistent in vivo for over 2 months. These results provide a powerful rationale for clinical testing of the combination of rituximab with autologous T cells carrying either CAR on aggressive or relapsed B-NHLs. PMID:20678160

  7. Sarcoidosis following successful treatment of pemphigus vulgaris with rituximab: a rituximab-induced reaction further supporting B-cell contribution to sarcoidosis pathogenesis?

    PubMed

    Galimberti, F; Fernandez, A P

    2016-06-01

    The anti-CD20 peripheral B-cell depleting monoclonal antibody, rituximab, has been shown to be a safe and effective treatment for refractory pemphigus vulgaris (PV), a potentially fatal autoimmune blistering disease. We report a patient who developed skin nodules and arthralgias following successful treatment of refractory PV with rituximab. Clinical, serological and histological findings were consistent with a diagnosis of sarcoidosis. The nodules promptly responded to treatment with corticosteroids, and resolved without recurrence when the medication was tapered several months later. The temporal onset of sarcoidosis following treatment with rituximab and the eventual resolution, coupled with the remarkable similarities between the B-cell immunological environment expected in our patient during the post-rituximab period and the immunological environment described in patients with idiopathic sarcoidosis, strongly implicates exposure to rituximab as the trigger for sarcoidosis development in our patient. We propose that rituximab-induced sarcoidal granulomas may be a rare adverse effect of treatment with this medication, providing further support for an important role of B cells in the pathogenesis of sarcoidosis. With better understanding of the circumstances surrounding sarcoidosis development following rituximab administration, this medication could potentially be used to induce sarcoidosis in animal research models to study the immunopathogenesis of this disease. PMID:26800651

  8. Rituximab as maintenance therapy for ANCA associated vasculitis: how, when and why?

    PubMed

    Alba, Marco A; Flores-Suárez, Luis Felipe

    2016-01-01

    ANCA-associated vasculitides (AAV) are chronic autoimmune diseases characterized by inflammation and destruction of small vessels. Rituximab is now licensed for use as a remission-induction agent in the treatment of these disorders. During recent years, several non-controlled studies have suggested that rituximab may be of value in maintaining disease remission in AAV. In these series, 3 techniques have been tried: "watch-and-wait", repeated cycles in fixed intervals, or administration based on proposed biomarkers. More importantly, the results of the MAINRITSAN trial showed that this anti-CD20 agent is superior to azathioprine for preventing major relapses in AAV. This review summarizes current information regarding the effectiveness, timing, dosing, duration and safety of rituximab as a valid option for remission maintenance. PMID:26255570

  9. Anti-CD20 IgA can protect mice against lymphoma development: evaluation of the direct impact of IgA and cytotoxic effector recruitment on CD20 target cells

    PubMed Central

    Pascal, Virginie; Laffleur, Brice; Debin, Arnaud; Cuvillier, Armelle; van Egmond, Marjolein; Drocourt, Daniel; Imbertie, Laurent; Pangault, Céline; Tarte, Karin; Tiraby, Gérard; Cogné, Michel

    2012-01-01

    Background While most antibody-based therapies use IgG because of their well-known biological properties, some functional limitations of these antibodies call for the development of derivatives with other therapeutic functions. Although less abundant than IgG in serum, IgA is the most abundantly produced Ig class in humans. Besides the specific targeting of its dimeric form to mucosal areas, IgA was shown to recruit polymorphonuclear neutrophils against certain targets more efficiently than does IgG1. Design and Methods In this study, we investigated the various pathways by which anti-tumor effects can be mediated by anti-CD20 IgA against lymphoma cells. Results We found that polymeric human IgA was significantly more effective than human IgG1 in mediating direct killing or growth inhibition of target cells in the absence of complement. We also demonstrated that this direct killing was able to indirectly induce the classical pathway of the complement cascade although to a lesser extent than direct recruitment of complement by IgG. Recruitment of the alternative complement pathway by specific IgA was also observed. In addition to activating complement for lysis of lymphoma cell lines or primary cells from patients with lymphoma, we showed that monomeric anti-CD20 IgA can effectively protect mice against tumor development in a passive immunization strategy and we demonstrated that this protective effect may be enhanced in mice expressing the human FcαRI receptor on their neutrophils. Conclusions We show that anti-CD20 IgA antibodies have original therapeutic properties against lymphoma cells, with strong direct effects, ability to recruit neutrophils for cell cytotoxicity and even recruitment of complement, although largely through an indirect way. PMID:22689689

  10. Anti-CD22 90Y-epratuzumab tetraxetan combined with anti-CD20 veltuzumab: a phase I study in patients with relapsed/refractory, aggressive non-Hodgkin lymphoma.

    PubMed

    Witzig, Thomas E; Tomblyn, Michael B; Misleh, Jamal G; Kio, Ebenezer A; Sharkey, Robert M; Wegener, William A; Goldenberg, David M

    2014-11-01

    A lingering criticism of radioimmunotherapy in non-Hodgkin lymphoma is the use of cold anti-CD20 antibody along with the radiolabeled anti-CD20 antibody. We instead combined radioimmunotherapy with immunotherapy targeting different B-cell antigens. We evaluated the anti-CD22 (90)Y-epratuzumab tetraxetan with the anti-CD20 veltuzumab in patients with aggressive lymphoma in whom at least one prior standard treatment had failed, but who had not undergone stem cell transplantation. Eighteen patients (median age 73 years, median of 3 prior treatments) received 200 mg/m(2) veltuzumab once-weekly for 4 weeks, with (90)Y-epratuzumab tetraxetan at planned doses in weeks 3 and 4, and (111)In-epratuzumab tetraxetan in week 2 for imaging and dosimetry. Veltuzumab effectively lowered levels of B cells in the blood prior to the radioimmunotherapy doses. No significant immunogenicity or change in pharmacokinetics of either agent occurred in combination. (111)In imaging showed tumor targeting with acceptable radiation dosimetry to normal organs. For (90)Y-epratuzumab tetraxetan, transient myelosuppression was dose-limiting with 6 mCi/m(2) (222 MBq/m(2)) × 2 being the maximal tolerated dose. Of 17 assessable patients, nine (53%) had objective responses according to the 2007 revised treatment response criteria, including three (18%) complete responses (2 relapsing after 11 and 13 months, 1 continuing to be clinically disease-free at 19 months), and six (35%) partial responses (1 relapsing after 14 months, 5 at 3 - 7 months). Responses occurred in patients with different lymphoma histologies, treated at different (90)Y dose levels, and with a predicted risk of poor outcome, most importantly including five of the six patients treated with the maximal tolerated dose (2 of whom achieved durable complete responses). In conclusion, the combination of (90)Y-epratuzumab tetraxetan and veltuzumab was well-tolerated with encouraging therapeutic activity in this difficult-to-treat population

  11. Is rituximab an effective treatment of refractory calcinosis?

    PubMed

    Dubos, Maria; Ly, Kim; Martel, Clothilde; Fauchais, Anne Laure

    2016-01-01

    Calcinosis, the deposition of calcified material in soft tissues, is frequently seen in systemic sclerosis and dermatomyositis. Treatment options are limited, with disappointing results. Some recent case reports suggest that rituximab may be an attractive therapeutic option. In case 1, a 54-year-old woman who presented with rheumatoid arthritis in association with scleromyositis was treated with rituximab for rheumatoid arthritis. Despite this, she developed multiple progressive calcinosis, necessitating extracorporeal shock wave lithotripsy to limit calcinosis extension and pain. In case 2, a 38-year-old man, previously treated for an anti-Pm/Scl-positive polymyositis/scleroderma overlap syndrome, presented with multiple tumoural periarticular calcinosis, which progressed despite bisphosphonates, sodium thiosulfate and thalidomide. We decided to start rituximab. Progression of calcinosis was still evident 6 and 12 months after anti-CD20 treatment. Many treatments have been tried to treat calcinosis without demonstrated effectiveness. Presently, rituximab cannot be recommended for this indication in the absence of successful controlled trials. PMID:27247203

  12. Rituximab Effectiveness and Safety for Treating Primary Sjögren’s Syndrome (pSS): Systematic Review and Meta-Analysis

    PubMed Central

    Souza, Francine Bertolais do Valle; Porfírio, Gustavo José Martiniano; Andriolo, Brenda Nazaré Gomes; de Albuquerque, Julia Vajda; Trevisani, Virginia Fernandes Moça

    2016-01-01

    Background Primary Sjögren’s Syndrome (pSS) is a systemic autoimmune disease that involves the exocrine glands and internal organs. pSS leads to destruction and loss of secretory function due to intense lymphoplasmacytic infiltration. Therapeutic options include mainly symptomatic and supportive measures, and traditional immunosuppressant drugs have shown no effectiveness in randomized trials. Rituximab (RTX) is a chimeric antibody anti-CD20 that leads to B cell depletion by diverse mechanisms. There is evidence that this drug may be effective for treating pSS. The objective of this systematic review was to evaluate Rituximab effectiveness and safety for treating pSS. Methods and Findings We conducted a systematic review of RCTs published until December 2015, with no language restriction. We registered a protocol on Plataforma Brasil (40654814.6.0000.5505) and developed search strategies for the following scientific databases: MEDLINE, EMBASE, CENTRAL and LILACS. We included adults with established pSS diagnosis and considered the use of Rituximab as intervention and the use of other drugs or placebo as control. Four studies met our eligibility criteria: three with low risk of bias and one with uncertain risk of bias. The total number of participants was 276 (145 RTX, 131 placebo). We assessed the risk of bias of each included study and evaluated the following as primary outcomes: lacrimal gland function, salivary gland function, fatigue improvement and adverse events. We found no significant differences between the groups in the Schirmer test at week 24 meta-analysis (MD 3.59, 95% CI -2.89 to 10.07). Only one study evaluated the lissamine green test and reported a statistically significant difference between the groups at week 24 (MD -2.00, 95% CI -3.52 to -0.48). There was a significant difference between the groups regarding salivary flow rate (MD 0.09, 95% CI 0.02 to 0.16) and improvement in fatigue VAS at weeks 6 (RR 3.98, 95% CI 1.61 to 9.82) and week 16

  13. Future therapies for pemphigus vulgaris: Rituximab and beyond.

    PubMed

    Huang, Amy; Madan, Raman K; Levitt, Jacob

    2016-04-01

    The conventional treatment for patients with pemphigus vulgaris (PV) centers on global immunosuppression, such as the use of steroids and other immunosuppressive drugs, to decrease titers of antidesmoglein autoantibodies responsible for the acantholytic blisters. Global immunosuppressants, however, cause serious side effects. The emergence of anti-CD20 biologic medications, such as rituximab, as an adjunct to conventional therapy has shifted the focus to targeted destruction of autoimmune B cells. Next-generation biologic medications with improved modes of delivery, pharmacology, and side effect profiles are constantly being developed, adding to the diversity of options for PV treatment. We review promising monoclonal antibodies, including veltuzumab, obinutuzumab (GA-101), ofatumumab, ocaratuzumab (AME-133v), PRO131921, and belimumab. PMID:26792592

  14. Improving testing for hepatitis B before treatment with rituximab

    PubMed Central

    Jopson, Laura; Ng, Sarah; Lowery, Matthew; Harwood, Jayne; Waugh, Sheila; Valappil, Manoj; McPherson, Stuart

    2016-01-01

    Aims/Objectives/Background Individuals with current or previous infection with the hepatitis B virus (HBV) can experience viral reactivation when treated with immunosuppression. Rituximab, an anti-CD20 antibody used to treat many diseases, has potent immunosuppressant effects with a high risk of causing HBV reactivation. Reactivation can range from elevated liver enzymes to acute severe hepatitis with liver failure and a significant mortality risk. HBV screening and appropriate use of prophylactic antiviral therapy can prevent reactivation. This work describes the introduction of a local policy for HBV testing in patients before rituximab treatment and assesses its impact. Methods and Results A baseline review (before policy introduction) of 90 patients showed that only 21 (23%) had hepatitis B surface antigen (HBsAg) and 17 (19%) had hepatitis B core antibody (anti-HBcAb) tested before receiving rituximab. Following introduction of the policy (on the basis of international guidelines), improved laboratory reporting protocols and targeted education sessions, two further reviews of HBV testing rates among patients being initiated onto rituximab were performed. There was a marked increase in pre-rituximab testing for HBsAg from 23 to 79% and for anti-HBcAb from 19 to 78%. Throughout the study period, a total of one (0.8%) HBsAg-positive and six (4.7%) anti-HBcAb-positive patients were identified. Conclusions This work clearly indicates that simple strategies can markedly improve appropriate HBV screening. In our cohort, 6% (of whom only 43% had recognized HBV risk factors) required antiviral prophylaxis, which emphasizes the importance of universal screening before rituximab. Reinforcement of the guidelines and ongoing education is needed to further increase testing rates. PMID:27388147

  15. Anti-CD20 single chain variable antibody fragment–apolipoprotein A-I chimera containing nanodisks promote targeted bioactive agent delivery to CD20-positive lymphomas

    PubMed Central

    Crosby, Natasha M.; Ghosh, Mistuni; Su, Betty; Beckstead, Jennifer A.; Kamei, Ayako; Simonsen, Jens B.; Luo, Bing; Gordon, Leo I.; Forte, Trudy M.; Ryan, Robert O.

    2015-01-01

    A fusion protein comprising an α-CD20 single chain variable fragment (scFv) antibody, a spacer peptide, and human apolipoprotein (apo) A-I was constructed and expressed in Escherichia coli. The lipid interaction properties intrinsic to apoA-I as well as the antigen recognition properties of the scFv were retained by the chimera. scFv•apoA-I was formulated into nanoscale reconstituted high-density lipoprotein particles (termed nanodisks; ND) and incubated with cultured cells. α-CD20 scFv•apoA-I ND bound to CD20-positive non-Hodgkins lymphoma (NHL) cells (Ramos and Granta) but not to CD20-negative T lymphocytes (i.e., Jurkat). Binding to NHL cells was partially inhibited by pre-incubation with rituximab, a monoclonal antibody directed against CD20. Confocal fluorescence microscopy analysis of Granta cells following incubation with α-CD20 scFv•apoA-I ND formulated with the intrinsically fluorescent hydrophobic polyphenol, curcumin, revealed α-CD20 scFv•apoA-I localizes to the cell surface, while curcumin off-loads and gains entry to the cell. Compared to control incubations, viability of cultured NHL cells was decreased upon incubation with α-CD20 scFv•apoA-I ND harboring curcumin. Thus, formulation of curcumin ND with α-CD20 scFv•apoA-I as the scaffold component confers cell targeting and enhanced bioactive agent delivery, providing a strategy to minimize toxicity associated with chemotherapeutic agents. PMID:25994015

  16. Anti-CD20 single chain variable antibody fragment-apolipoprotein A-I chimera containing nanodisks promote targeted bioactive agent delivery to CD20-positive lymphomas.

    PubMed

    Crosby, Natasha M; Ghosh, Mistuni; Su, Betty; Beckstead, Jennifer A; Kamei, Ayako; Simonsen, Jens B; Luo, Bing; Gordon, Leo I; Forte, Trudy M; Ryan, Robert O

    2015-08-01

    A fusion protein comprising an α-CD20 single chain variable fragment (scFv) antibody, a spacer peptide, and human apolipoprotein (apo) A-I was constructed and expressed in Escherichia coli. The lipid interaction properties intrinsic to apoA-I as well as the antigen recognition properties of the scFv were retained by the chimera. scFv•apoA-I was formulated into nanoscale reconstituted high-density lipoprotein particles (termed nanodisks; ND) and incubated with cultured cells. α-CD20 scFv•apoA-I ND bound to CD20-positive non-Hodgkins lymphoma (NHL) cells (Ramos and Granta) but not to CD20-negative T lymphocytes (i.e., Jurkat). Binding to NHL cells was partially inhibited by pre-incubation with rituximab, a monoclonal antibody directed against CD20. Confocal fluorescence microscopy analysis of Granta cells following incubation with α-CD20 scFv•apoA-I ND formulated with the intrinsically fluorescent hydrophobic polyphenol, curcumin, revealed α-CD20 scFv•apoA-I localizes to the cell surface, while curcumin off-loads and gains entry to the cell. Compared to control incubations, viability of cultured NHL cells was decreased upon incubation with α-CD20 scFv•apoA-I ND harboring curcumin. Thus, formulation of curcumin ND with α-CD20 scFv•apoA-I as the scaffold component confers cell targeting and enhanced bioactive agent delivery, providing a strategy to minimize toxicity associated with chemotherapeutic agents. PMID:25994015

  17. Early-onset neutropenia induced by rituximab in a patient with lupus nephritis and hemolytic anemia.

    PubMed

    Arroyo-Ávila, Mariangelí; Fred-Jiménez, Ruth M; Vilá, Luis M

    2015-01-01

    Rituximab is an anti-CD20 monoclonal antibody that has been used to treat several complications of systemic lupus erythematosus (SLE) including nephritis, cerebritis, and hematological disorders. Neutropenia is among the adverse events associated with rituximab; this usually occurs several weeks after therapy. However, early-onset neutropenia has been reported only in a few cases. Herein, we describe a 36-year-old Hispanic SLE woman who developed severe early-onset neutropenia (0.3 × 10(9)/L) after the second weekly rituximab infusion (375 mg/m(2) weekly × 4) given for nephritis and hemolytic anemia. She also had early-onset thrombocytopenia after rituximab therapy. Both hematological disorders resolved 12 days after the fourth and final dose. This case, together with few others, suggests that early-onset neutropenia may occur during rituximab therapy. Even though rituximab-induced neutropenia seems to be transient, it may predispose SLE patients to severe complications such as infections. PMID:25767732

  18. Early-Onset Neutropenia Induced by Rituximab in a Patient with Lupus Nephritis and Hemolytic Anemia

    PubMed Central

    Arroyo-Ávila, Mariangelí; Fred-Jiménez, Ruth M.; Vilá, Luis M.

    2015-01-01

    Rituximab is an anti-CD20 monoclonal antibody that has been used to treat several complications of systemic lupus erythematosus (SLE) including nephritis, cerebritis, and hematological disorders. Neutropenia is among the adverse events associated with rituximab; this usually occurs several weeks after therapy. However, early-onset neutropenia has been reported only in a few cases. Herein, we describe a 36-year-old Hispanic SLE woman who developed severe early-onset neutropenia (0.3 × 109/L) after the second weekly rituximab infusion (375 mg/m2 weekly × 4) given for nephritis and hemolytic anemia. She also had early-onset thrombocytopenia after rituximab therapy. Both hematological disorders resolved 12 days after the fourth and final dose. This case, together with few others, suggests that early-onset neutropenia may occur during rituximab therapy. Even though rituximab-induced neutropenia seems to be transient, it may predispose SLE patients to severe complications such as infections. PMID:25767732

  19. Anti-CD22 90Y-epratuzumab tetraxetan combined with anti-CD20 veltuzumab: a phase I study in patients with relapsed/refractory, aggressive non-Hodgkin lymphoma

    PubMed Central

    Witzig, Thomas E.; Tomblyn, Michael B.; Misleh, Jamal G.; Kio, Ebenezer A.; Sharkey, Robert M.; Wegener, William A.; Goldenberg, David M.

    2014-01-01

    A lingering criticism of radioimmunotherapy in non-Hodgkin lymphoma is the use of cold anti-CD20 antibody along with the radiolabeled anti-CD20 antibody. We instead combined radioimmunotherapy with immunotherapy targeting different B-cell antigens. We evaluated the anti-CD22 90Y-epratuzumab tetraxetan with the anti-CD20 veltuzumab in patients with aggressive lymphoma in whom at least one prior standard treatment had failed, but who had not undergone stem cell transplantation. Eighteen patients (median age 73 years, median of 3 prior treatments) received 200 mg/m2 veltuzumab once-weekly for 4 weeks, with 90Y-epratuzumab tetraxetan at planned doses in weeks 3 and 4, and 111In-epratuzumab tetraxetan in week 2 for imaging and dosimetry. Veltuzumab effectively lowered levels of B cells in the blood prior to the radioimmunotherapy doses. No significant immunogenicity or change in pharmacokinetics of either agent occurred in combination. 111In imaging showed tumor targeting with acceptable radiation dosimetry to normal organs. For 90Y-epratuzumab tetraxetan, transient myelosuppression was dose-limiting with 6 mCi/m2 (222 MBq/m2) × 2 being the maximal tolerated dose. Of 17 assessable patients, nine (53%) had objective responses according to the 2007 revised treatment response criteria, including three (18%) complete responses (2 relapsing after 11 and 13 months, 1 continuing to be clinically disease-free at 19 months), and six (35%) partial responses (1 relapsing after 14 months, 5 at 3 – 7 months). Responses occurred in patients with different lymphoma histologies, treated at different 90Y dose levels, and with a predicted risk of poor outcome, most importantly including five of the six patients treated with the maximal tolerated dose (2 of whom achieved durable complete responses). In conclusion, the combination of 90Y-epratuzumab tetraxetan and veltuzumab was well-tolerated with encouraging therapeutic activity in this difficult-to-treat population. PMID:25150258

  20. Generation of biologically active linear and cyclic peptides has revealed a unique fine specificity of rituximab and its possible cross-reactivity with acid sphingomyelinase-like phosphodiesterase 3b precursor.

    PubMed

    Perosa, Federico; Favoino, Elvira; Caragnano, Maria Antonietta; Dammacco, Franco

    2006-02-01

    Heterogeneity of the effector functions displayed by rituximab and other anti-CD20 monoclonal antibodies (mAbs) apparently recognizing the same CD20 epitope suggests that additional mechanisms, probably related to mAb fine specificity, are responsible for B-cell depletion. To improve our understanding of rituximab's function, its fine specificity was investigated by means of phage display peptide library (PDPL)-expressing 7-mer cyclic (c7c) or 7-/12-mer linear peptides. Rituximab-specific c7c PDPL-derived clone insert sequences expressed the motif A(S)NPS overlapping the human CD20 170ANPS173. P172 was the most critical for rituximab binding, since its replacement with S172 (of mouse CD20) abolished the reactivity. The WPXWLE motif expressed by the linear PDPL-derived clone insert sequences could only be aligned to the reverse-oriented 161WPXWLE156 of acid sphingomyelinase-like phosphodiesterase 3b precursor (ASMLPD), though linear peptides bearing WPXWLE competed with cyclic ones for rituximab-paratope binding. Anti-CD20 mAb 1F5 only displayed a reactivity profile similar to that of rituximab, which also reacted with ASMLPD-derived peptides. Peptides induced antibodies with specificity and effector functions similar to those of rituximab. Our results show a unique fine specificity of rituximab, define the molecular basis for the lack of rituximab reactivity with mouse CD20 (mCD20), and the potential of targeting CD20 in an active immunotherapy setting. A possible rituximab interaction with ASMLPD is suggested. PMID:16223774

  1. High-Dose [131I]Tositumomab (anti-CD20) Radioimmunotherapy and Autologous Hematopoietic Stem Cell Transplantation for Adults ≥ 60 Years Old with Relapsed or Refractory B-Cell Lymphoma

    SciTech Connect

    Gopal, Ajay K.; Rajendran, Joseph G.; Gooley, Ted; Pagel, John M.; Fisher, Darrell R.; Petersdorf, Stephen; Maloney, David G.; Eary, Janet F.; Appelbaum, Frederick R.; Press, Oliver W.

    2007-04-10

    Purpose: The majority of patients with relapsed or refractory B-cell, non-Hodgkin’s lymphoma (NHL) are over 60 years of age, yet they are often denied potentially curative high-dose therapy and autologous stem cell transplants (ASCT) due to the risk of excessive treatment-related morbidity and mortality. Myeloablative anti-CD20 radioimmunotherapy (RIT) can deliver curative radiation doses to tumor sites while limiting exposure to normal organs and may be particularly suited for older adults requiring high-dose therapy. Methods: Patients over age 60 with relapsed B-NHL received infusions of tositumomab anti-CD20 antibody labeled with 5-10mCi I-131 tracer for dosimetry purposes followed 10 days later by individualized therapeutic infusions of I-131-tositumomab (median 525 mCi, range 328-1154 mCi) to deliver 25-27Gy to the critical normal organ receiving the highest radiation dose. ASCT was performed approximately 2 weeks after therapy. Results: Twenty-four patients with a median age of 64 (range 60-76) who had received a median of four prior regimens (range 2-14) were treated. Thirteen (54%) had chemotherapy-resistant disease. The estimated 3-year overall and progression-free survivals were 59% and 51%, respectively with a median follow-up of 2.9 years (range 1-6 years). All patients experienced expected myeloablation with engraftment of platelets (≥20K/µL) and neutrophils (≥500/µL) occurring a median of 9 and 15 days, respectively following ASCT. There were no treatment-related deaths, and only two patients experienced grade 4 non-hematologic toxicity. Conclusions: Myeloablative RIT and ASCT is a safe and effective therapeutic option for older adults with relapsed B-NHL.

  2. Rituximab does not reset defective early B cell tolerance checkpoints

    PubMed Central

    Chamberlain, Nicolas; Massad, Christopher; Oe, Tyler; Cantaert, Tineke; Herold, Kevan C.; Meffre, Eric

    2015-01-01

    Type 1 diabetes (T1D) patients show abnormalities in early B cell tolerance checkpoints, resulting in the accumulation of large numbers of autoreactive B cells in their blood. Treatment with rituximab, an anti-CD20 mAb that depletes B cells, has been shown to preserve β cell function in T1D patients and improve other autoimmune diseases, including rheumatoid arthritis and multiple sclerosis. However, it remains largely unknown how anti–B cell therapy thwarts autoimmunity in these pathologies. Here, we analyzed the reactivity of Abs expressed by single, mature naive B cells from 4 patients with T1D before and 52 weeks after treatment to determine whether rituximab resets early B cell tolerance checkpoints. We found that anti–B cell therapy did not alter the frequencies of autoreactive and polyreactive B cells, which remained elevated in the blood of all patients after rituximab treatment. Moreover, the limited proliferative history of autoreactive B cells after treatment revealed that these clones were newly generated B cells and not self-reactive B cells that had escaped depletion and repopulated the periphery through homeostatic expansion. We conclude that anti–B cell therapy may provide a temporary dampening of autoimmune processes through B cell depletion. However, repletion with autoreactive B cells may explain the relapse that occurs in many autoimmune patients after anti–B cell therapy. PMID:26642366

  3. Place in therapy of rituximab in the treatment of granulomatosis with polyangiitis and microscopic polyangiitis

    PubMed Central

    Shah, Shivani; Geetha, Duvuru

    2015-01-01

    Granulomatosis with polyangiitis and microscopic polyangiitis are small vessel vasculitides characterized by circulating antineutrophil circulating antibodies. Standard treatment for active severe disease has consisted of cyclophosphamide with glucocorticoids with or without plasmapheresis, which achieves approximately 75% sustained remission, but carries significant adverse effects such as malignancy, infertility, leukopenia, and infections. The role of B cells in the pathogenesis of anti-neutrophil circulating antibodies-associated vasculitis has been established, and as such, rituximab, a monoclonal anti-CD20 antibody, has been studied in treatment of active granulomatosis with polyangiitis and microscopic polyangiitis (induction) and in maintaining remission. Rituximab has been shown to be effective in inducing remission in several retrospective studies in patients with refractory disease or cyclophosphamide intolerance. The RAVE and RITUXVAS trials demonstrated rituximab is a noninferior alternative to standard cyclophosphamide-based therapy; however, its role in elderly patients and patients with severe renal disease warrants further investigation. Rituximab has been compared with azathioprine for maintaining remission in the MAINRITSAN trial and may be more efficacious in maintaining remission in patients treated with cyclophosphamide induction. Rituximab is not without risks and carries a similar adverse event risk rate as cyclophosphamide in randomized control trials. However, its use can be considered over cyclophosphamide in patients who have relapsing or refractory disease or in young patients seeking to preserve fertility.

  4. Rituximab as Single Agent in Primary MALT Lymphoma of the Ocular Adnexa

    PubMed Central

    Annibali, Ombretta; Chiodi, Francesca; Sarlo, Chiara; Cortes, Magdalena; Quaranta-Leoni, Francesco M.; Quattrocchi, Carlo; Bianchi, Antonella; Bonini, Stefano; Avvisati, Giuseppe

    2015-01-01

    Ocular Adnexal Lymphomas are the first cause of primary ocular malignancies, and among them the most common are MALT Ocular Adnexal Lymphomas. Recently systemic immunotherapy with anti-CD20 monoclonal antibody has been investigated as first-line treatment; however, the optimal management for MALT Ocular Adnexal Lymphomas is still unknown. The present study evaluated retrospectively the outcome of seven consecutive patients with primary MALT Ocular Adnexal Lymphomas, of whom six were treated with single agent Rituximab. All patients received 6 cycles of Rituximab 375 mg/mq every 3 weeks intravenously. The overall response rate was 100%; four patients (67%) achieved a Complete Remission, and two (33%) achieved a partial response. In four patients an additional Rituximab maintenance every 2-3 months was given for two years. After a median follow-up of 29 months (range 8–34), no recurrences were observed, without of therapy- or disease-related severe adverse events. None of the patients needed additional radiotherapy or other treatments. Rituximab as a single agent is highly effective and tolerable in first-line treatment of primary MALT Ocular adnexal Lymphomas. Furthermore, durable responses are achievable with the same-agent maintenance. Rituximab can be considered the agent of choice in the management of an indolent disease in whom the “quality of life” matter is of primary importance. PMID:26425558

  5. Immunotherapy with the trifunctional anti-CD20 x anti-CD3 antibody FBTA05 (Lymphomun) in paediatric high-risk patients with recurrent CD20-positive B cell malignancies.

    PubMed

    Schuster, Friedhelm R; Stanglmaier, Michael; Woessmann, Wilhelm; Winkler, Beate; Siepermann, Meinolf; Meisel, Roland; Schlegel, Paul G; Hess, Jürgen; Lindhofer, Horst; Borkhardt, Arndt; Buhmann, Raymund

    2015-04-01

    Children with B cell malignancies refractory to standard therapy are known to have a poor prognosis and very limited treatment options. Here, we report on the treatment and follow-up of ten patients diagnosed with relapsed or refractory mature B-cell Non Hodgkin Lymphoma (B-NHL), Burkitt leukaemia (B-AL) or pre B-acute lymphoblastic leukaemia (pre B-ALL). All children were treated with FBTA05 (now designated Lymphomun), an anti-CD3 x anti-CD20 trifunctional bispecific antibody (trAb) in compassionate use. Within individual treatment schedules, Lymphomun was applied (a) after allogeneic stem cell transplantation (allo-SCT, n = 6) to induce sustained long-term remission, or (b) stand alone prior to subsequent chemotherapy to eradicate residual disease before allo-SCT (n = 4). Nine of ten children displayed a clinical response: three stable diseases (SD), one partial remission (PR) and five induced or sustained complete remissions (CR). Five of these nine responders died during follow-up. The other patients still maintain CR with a current overall survival of 874-1424 days (median: 1150 days). In conclusion, despite the dismal clinical prognosis of children refractory to standard therapy, immunotherapy with Lymphomun resulted in a favourable clinical outcome in this cohort of refractory paediatric patients. PMID:25495919

  6. Immunreconstitution and Infectious Complications After Rituximab Treatment in Children and Adolescents: What Do We Know and What Can We Learn from Adults?

    PubMed Central

    Worch, Jennifer; Makarova, Olga; Burkhardt, Birgit

    2015-01-01

    Rituximab, an anti CD20 monoclonal antibody, is widely used in the treatment of B-cell malignancies in adults and increasingly in pediatric patients. By depleting B-cells, rituximab interferes with humoral immunity. This review provides a comprehensive overview of immune reconstitution and infectious complications after rituximab treatment in children and adolescents. Immune reconstitution starts usually after six months with recovery to normal between nine to twelve months. Extended rituximab treatment results in a prolonged recovery of B-cells without an increase of clinically relevant infections. The kinetic of B-cell recovery is influenced by the concomitant chemotherapy and the underlying disease. Intensive B-NHL treatment such as high-dose chemotherapy followed by rituximab bears a risk for prolonged hypogammaglobulinemia. Overall transient alteration of immune reconstitution and infections after rituximab treatment are acceptable for children and adolescent without significant differences compared to adults. However, age related disparities in the kinetic of immune reconstitution and the definitive role of rituximab in the treatment for children and adolescents with B-cell malignancies need to be evaluated in prospective controlled clinical trials. PMID:25643241

  7. Immunreconstitution and infectious complications after rituximab treatment in children and adolescents: what do we know and what can we learn from adults?

    PubMed

    Worch, Jennifer; Makarova, Olga; Burkhardt, Birgit

    2015-01-01

    Rituximab, an anti CD20 monoclonal antibody, is widely used in the treatment of B-cell malignancies in adults and increasingly in pediatric patients. By depleting B-cells, rituximab interferes with humoral immunity. This review provides a comprehensive overview of immune reconstitution and infectious complications after rituximab treatment in children and adolescents. Immune reconstitution starts usually after six months with recovery to normal between nine to twelve months. Extended rituximab treatment results in a prolonged recovery of B-cells without an increase of clinically relevant infections. The kinetic of B-cell recovery is influenced by the concomitant chemotherapy and the underlying disease. Intensive B-NHL treatment such as high-dose chemotherapy followed by rituximab bears a risk for prolonged hypogammaglobulinemia. Overall transient alteration of immune reconstitution and infections after rituximab treatment are acceptable for children and adolescent without significant differences compared to adults. However, age related disparities in the kinetic of immune reconstitution and the definitive role of rituximab in the treatment for children and adolescents with B-cell malignancies need to be evaluated in prospective controlled clinical trials. PMID:25643241

  8. High in Vitro Anti-Tumor Efficacy of Dimeric Rituximab/Saporin-S6 Immunotoxin

    PubMed Central

    Bortolotti, Massimo; Bolognesi, Andrea; Battelli, Maria Giulia; Polito, Letizia

    2016-01-01

    The anti-CD20 mAb Rituximab has revolutionized lymphoma therapy, in spite of a number of unresponsive or relapsing patients. Immunotoxins, consisting of toxins coupled to antibodies, are being investigated for their potential ability to augment Rituximab efficacy. Here, we compare the anti-tumor effect of high- and low-molecular-weight Rituximab/saporin-S6 immunotoxins, named HMW-IT and LMW-IT, respectively. Saporin-S6 is a potent and stable plant enzyme belonging to ribosome-inactivating proteins that causes protein synthesis arrest and consequent cell death. Saporin-S6 was conjugated to Rituximab through an artificial disulfide bond. The inhibitory activity of HMW-IT and LMW-IT was evaluated on cell-free protein synthesis and in two CD20+ lymphoma cell lines, Raji and D430B. Two different conjugates were separated on the basis of their molecular weight and further characterized. Both HMW-IT (dimeric) and LMW-IT (monomeric) maintained a high level of enzymatic activity in a cell-free system. HMW-IT, thanks to a higher toxin payload and more efficient antigen capping, showed stronger in vitro anti-tumor efficacy than LMW-IT against lymphoma cells. Dimeric HMW-IT can be used for lymphoma therapy at least for ex vivo treatments. The possibility of using HMW-IT augments the yield in immunotoxin preparation and allows the targeting of antigens with low internalization rates. PMID:27338475

  9. High in Vitro Anti-Tumor Efficacy of Dimeric Rituximab/Saporin-S6 Immunotoxin.

    PubMed

    Bortolotti, Massimo; Bolognesi, Andrea; Battelli, Maria Giulia; Polito, Letizia

    2016-01-01

    The anti-CD20 mAb Rituximab has revolutionized lymphoma therapy, in spite of a number of unresponsive or relapsing patients. Immunotoxins, consisting of toxins coupled to antibodies, are being investigated for their potential ability to augment Rituximab efficacy. Here, we compare the anti-tumor effect of high- and low-molecular-weight Rituximab/saporin-S6 immunotoxins, named HMW-IT and LMW-IT, respectively. Saporin-S6 is a potent and stable plant enzyme belonging to ribosome-inactivating proteins that causes protein synthesis arrest and consequent cell death. Saporin-S6 was conjugated to Rituximab through an artificial disulfide bond. The inhibitory activity of HMW-IT and LMW-IT was evaluated on cell-free protein synthesis and in two CD20⁺ lymphoma cell lines, Raji and D430B. Two different conjugates were separated on the basis of their molecular weight and further characterized. Both HMW-IT (dimeric) and LMW-IT (monomeric) maintained a high level of enzymatic activity in a cell-free system. HMW-IT, thanks to a higher toxin payload and more efficient antigen capping, showed stronger in vitro anti-tumor efficacy than LMW-IT against lymphoma cells. Dimeric HMW-IT can be used for lymphoma therapy at least for ex vivo treatments. The possibility of using HMW-IT augments the yield in immunotoxin preparation and allows the targeting of antigens with low internalization rates. PMID:27338475

  10. Rituximab for the treatment of rheumatoid arthritis: an update

    PubMed Central

    Mok, Chi Chiu

    2014-01-01

    Rituximab is a chimeric monoclonal antibody that targets the CD20 molecule expressed on the surface of B cells. It was first used in the treatment of non-Hodgkin’s lymphoma and later approved for the treatment of rheumatoid arthritis (RA) that does not respond adequately to disease-modifying antirheumatic drugs, including the anti-tumor-necrosis-factor (TNF) biologics. Sustained efficacy in RA can be achieved by repeated courses of rituximab. However, the optimal dose and retreatment schedule of rituximab in RA remains to be established. Seropositivity, complete B cell depletion shortly after treatment, and previous failure to no more than one anti-TNF agent are three factors associated with greater clinical benefits to rituximab. Infusion reaction to the first dose of rituximab occurs in approximately 25% of RA patients, and the incidence reduces with subsequent exposure. Immunogenicity to the chimeric compound occurs in 11% of RA patients, but this does not correlate with its efficacy in B cell depletion. Extended observation of randomized controlled trials in RA does not reveal a significant increase in the incidence of serious infections related to rituximab compared to placebo groups, and the infection rate remains static over time. Repeated treatment with rituximab is associated with hypogammaglobulinemia, which may increase the risk of serious, but rarely opportunistic, infections. Reactivation of occult hepatitis B infection has been reported in RA patients receiving rituximab, but no increase in the incidence of tuberculosis was observed. Screening for baseline serum immunoglobulin G level and hepatitis B status (including occult infection) is important, especially in Asian countries where hepatitis B infection is prevalent. The rare but fatal progressive multifocal leukoencephalopathy linked to the use of rituximab has to be noted. Postmarketing surveillance and registry data, particularly in Asia, are necessary to establish the long-term efficacy and

  11. Chemokine/cytokine profiling after rituximab: reciprocal expression of BCA-1/CXCL13 and BAFF in childhood OMS.

    PubMed

    Pranzatelli, Michael R; Tate, Elizabeth D; Travelstead, Anna L; Verhulst, Steven J

    2011-03-01

    The aim of the study was to test the hypothesis that B-cell repopulation following rituximab (anti-CD20) therapy is orchestrated by chemokines and non-chemokine cytokines. Twenty-five children with opsoclonus-myoclonus syndrome (OMS) received rituximab with or without conventional agents. A comprehensive panel of 40 chemokines and other cytokines were measured in serum by ELISA and multiplexed fluorescent bead-based immunoassay. Serum BAFF concentration changed dramatically (even after first infusion) and inversely with B-cell depletion/repopulation and CXCL13 concentration at 1, 3, and 6 months. Negative correlations were found for BAFF concentration vs blood B cell percentage and serum CXCL13 concentration; positive correlations with serum rituximab concentrations. Six months after initiation of therapy, no significant difference in the levels of APRIL, CXCL10, IL-6, or 17 other cytokines/chemokines were detected. These data reveal a major role for BAFF in peripheral B cell repopulation following rituximab-induced B-cell depletion, and novel changes in CXCL13. ClinicalTrials.gov NCT0024436. PMID:21211990

  12. Standard Operating Procedure for Prospective Individualised Dosimetry for ([131])I-rituximab Radioimmunotherapy of Non-Hodgkin's Lymphoma.

    PubMed

    Calais, Phillipe J; Turner, J Harvey

    2012-09-01

    Radioimmunotherapy (RIT) is an attractive therapy for non-Hodgkin's lymphoma (NHL) as it allows targeted tumor irradiation which provides a cytotoxic effect significantly greater than that of the immune-mediated effects of a non-radioactive, or 'cold', antibody alone. Anti-CD20 antibodies such as rituximab are ideal for RIT, as not only is it easily iodinated, but the CD20 antigen is found on more than 95% of B-cell NHL. A standard operating procedure (SOP) has been formulated for personalized prospective dosimetry for safe, effective outpatient (131)I-rituximab RIT of NHL. Over five years, experience of treatment of outpatients with (131)I-rituximab was analyzed with respect to critical organ radiation dose in patients and radiation exposure of their carers. This radiation safety methodology has been refined; and offers the potential for safe, practical application to outpatient (131)I-rituximab RIT of lymphoma in general and in developing countries in particular. Given endorsement and sanction of this SOP by local regulatory authorities the personalized dosimetry paradigm will facilitate incorporation of RIT into the routine clinical practice of therapeutic nuclear oncology worldwide. PMID:23372448

  13. IMPACT OF PRE-TRANSPLANT RITUXIMAB ON SURVIVAL AFTER AUTOLOGOUS HEMATOPOIETIC STEM CELL TRANSPLANTATION FOR DIFFUSE LARGE B-CELL LYMPHOMA

    PubMed Central

    Fenske, Timothy S.; Hari, Parameswaran N.; Carreras, Jeanette; Zhang, Mei-Jie; Kamble, Rammurti T.; Bolwell, Brian J.; Cairo, Mitchell S.; Champlin, Richard E.; Chen, Yi-Bin; Freytes, César O.; Gale, Robert Peter; Hale, Gregory A.; Ilhan, Osman; Khoury, H. Jean; Lister, John; Maharaj, Dipnarine; Marks, David I.; Munker, Reinhold; Pecora, Andrew L.; Rowlings, Philip A.; Shea, Thomas C.; Stiff, Patrick; Wiernik, Peter H.; Winter, Jane N.; Rizzo, J. Douglas; van Besien, Koen; Lazarus, Hillard M.; Vose, Julie M.

    2010-01-01

    Incorporation of the anti-CD20 monoclonal antibody rituximab into front-line regimens for diffuse large B-cell lymphoma (DLBCL) has resulted in improved survival. Despite this progress, many patients develop refractory or recurrent DLBCL and then receive autologous hematopoietic stem cell transplantation (AuHCT). It is unclear to what extent pre-transplant exposure to rituximab affects outcomes following AuHCT. Outcomes of 994 patients receiving AuHCT for DLBCL between 1996 and 2003 were analyzed according to whether rituximab was (n=176, “+R” group) or was not (n=818, “ −R” group) administered with front-line or salvage therapy prior to AuHCT. The +R group had superior progression-free survival (50% versus 38%, p=0.008) and overall survival (57% versus 45%, p=0.006) at 3 years. Platelet and neutrophil engraftment were not affected by exposure to rituximab. Non-relapse mortality (NRM) did not differ significantly between the +R and −R groups. In multivariate analysis, the +R group had improved progression-free survival (relative risk of relapse/progression or death 0.64, p<0.001) and improved overall survival (relative risk of death of 0.74, p=0.039). We conclude that pre-transplant rituximab is associated with a lower rate of progression and improved survival following AuHCT for DLBCL, with no evidence of impaired engraftment or increased NRM. PMID:19822306

  14. Long-term follow up of the FL2000 study comparing CHVP-interferon to CHVP-interferon plus rituximab in follicular lymphoma

    PubMed Central

    Bachy, Emmanuel; Houot, Roch; Morschhauser, Franck; Sonet, Anne; Brice, Pauline; Belhadj, Karim; Cartron, Guillaume; Audhuy, Bruno; Fermé, Christophe; Feugier, Pierre; Sebban, Catherine; Delwail, Vincent; Maisonneuve, Hervé; Le Gouill, Steven; Lefort, Sophie; Brousse, Nicole; Foussard, Charles; Salles, Gilles

    2013-01-01

    Anti-CD20-containing chemotherapy regimens have become the standard of care for patients with follicular lymphoma needing cytotoxic therapy. Four randomized trials demonstrated a clinical benefit for patients treated with rituximab. However, no long-term follow up (i.e. > 5 years) of these trials is yet available. Between May 2000 and May 2002, 358 newly diagnosed patients with high tumor burden follicular lymphoma were randomized to receive cyclophosphamide, adriamycin, etoposide and prednisolone plus interferon-α2a or a similar chemotherapy-based regimen plus rituximab, and outcome was up-dated. With a median follow up of 8.3 years, addition of rituximab remained significantly associated with prolonged event-free survival (primary end point) (P=0.0004) with a trend towards a benefit for overall survival (P=0.076). The Follicular Lymphoma International Prognostic Index score was strongly associated with outcome for both event-free and overall survival in univariate analysis and its prognostic value remained highly significant after adjusting for other significant covariates in multivariate models (P<0.0001 and P=0.001, respectively). Considering long-term toxicity, the addition of rituximab in the first-line setting was confirmed as safe with regards to development of secondary malignancies. Long-term follow up of patients with follicular lymphoma treated in the FL2000 study confirms the sustained clinical benefit of rituximab without long-term toxicity. This study was registered at ClinicalTrials.gov (Identifier:00136552). PMID:23645690

  15. Long-term follow up of the FL2000 study comparing CHVP-interferon to CHVP-interferon plus rituximab in follicular lymphoma.

    PubMed

    Bachy, Emmanuel; Houot, Roch; Morschhauser, Franck; Sonet, Anne; Brice, Pauline; Belhadj, Karim; Cartron, Guillaume; Audhuy, Bruno; Fermé, Christophe; Feugier, Pierre; Sebban, Catherine; Delwail, Vincent; Maisonneuve, Hervé; Le Gouill, Steven; Lefort, Sophie; Brousse, Nicole; Foussard, Charles; Salles, Gilles

    2013-07-01

    Anti-CD20-containing chemotherapy regimens have become the standard of care for patients with follicular lymphoma needing cytotoxic therapy. Four randomized trials demonstrated a clinical benefit for patients treated with rituximab. However, no long-term follow up (i.e. > 5 years) of these trials is yet available. Between May 2000 and May 2002, 358 newly diagnosed patients with high tumor burden follicular lymphoma were randomized to receive cyclophosphamide, adriamycin, etoposide and prednisolone plus interferon-α2a or a similar chemotherapy-based regimen plus rituximab, and outcome was up-dated. With a median follow up of 8.3 years, addition of rituximab remained significantly associated with prolonged event-free survival (primary end point) (P=0.0004) with a trend towards a benefit for overall survival (P=0.076). The Follicular Lymphoma International Prognostic Index score was strongly associated with outcome for both event-free and overall survival in univariate analysis and its prognostic value remained highly significant after adjusting for other significant covariates in multivariate models (P<0.0001 and P=0.001, respectively). Considering long-term toxicity, the addition of rituximab in the first-line setting was confirmed as safe with regards to development of secondary malignancies. Long-term follow up of patients with follicular lymphoma treated in the FL2000 study confirms the sustained clinical benefit of rituximab without long-term toxicity. PMID:23645690

  16. Stiff-person syndrome treated with rituximab

    PubMed Central

    Lobo, Marcelo Evangelista; Araújo, Marx Lincoln Barros; Tomaz, Carlos Alberto Bezerra; Allam, Nasser

    2010-01-01

    Stiff-person syndrome (SPS) is a rare neurological condition consisting of progressive and fluctuating rigidity of the axial muscles combined with painful spasms. The pathophysiology of SPS is not fully understood, but there seems to be an autoimmune component. The use of rituximab, a chimeric monoclonal antibody targeting CD20 protein in the surface of mature B cells, for the treatment of SPS is a recent therapeutical approach showing promising results. The authors present a case report of a 41-year-old female patient diagnosed with SPS who was treated with rituximab in a public hospital in Brasília, Brazil, showing a good and safe response to the treatment so far. Our data go along with some recent articles published in the literature. PMID:22802263

  17. Increasing the efficacy of CD20 antibody therapy through the engineering of a new type II anti-CD20 antibody with enhanced direct and immune effector cell–mediated B-cell cytotoxicity

    PubMed Central

    Mössner, Ekkehard; Brünker, Peter; Moser, Samuel; Püntener, Ursula; Schmidt, Carla; Herter, Sylvia; Grau, Roger; Gerdes, Christian; Nopora, Adam; van Puijenbroek, Erwin; Ferrara, Claudia; Sondermann, Peter; Jäger, Christiane; Strein, Pamela; Fertig, Georg; Friess, Thomas; Schüll, Christine; Bauer, Sabine; Dal Porto, Joseph; Del Nagro, Christopher; Dabbagh, Karim; Dyer, Martin J. S.; Poppema, Sibrand; Klein, Christian

    2010-01-01

    CD20 is an important target for the treatment of B-cell malignancies, including non-Hodgkin lymphoma as well as autoimmune disorders. B-cell depletion therapy using monoclonal antibodies against CD20, such as rituximab, has revolutionized the treatment of these disorders, greatly improving overall survival in patients. Here, we report the development of GA101 as the first Fc-engineered, type II humanized IgG1 antibody against CD20. Relative to rituximab, GA101 has increased direct and immune effector cell-mediated cytotoxicity and exhibits superior activity in cellular assays and whole blood B-cell depletion assays. In human lymphoma xenograft models, GA101 exhibits superior antitumor activity, resulting in the induction of complete tumor remission and increased overall survival. In nonhuman primates, GA101 demonstrates superior B cell–depleting activity in lymphoid tissue, including in lymph nodes and spleen. Taken together, these results provide compelling evidence for the development of GA101 as a promising new therapy for the treatment of B-cell disorders. PMID:20194898

  18. A phase 2 study of inotuzumab ozogamicin in patients with indolent B-cell non-Hodgkin lymphoma refractory to rituximab alone, rituximab and chemotherapy, or radioimmunotherapy.

    PubMed

    Goy, Andre; Forero, Andres; Wagner-Johnston, Nina; Christopher Ehmann, W; Tsai, Michaela; Hatake, Kiyohiko; Ananthakrishnan, Revathi; Volkert, Angela; Vandendries, Erik; Ogura, Michinori

    2016-08-01

    This phase 2 study evaluated the efficacy and safety of inotuzumab ozogamicin (InO) in patients with indolent B-cell non-Hodgkin lymphoma (NHL) refractory to rituximab alone, rituximab plus chemotherapy or anti-CD20 radioimmunotherapy. Patients received InO 1·8 mg/m(2) intravenously on a 28-d cycle for a planned 4-8 cycles. The initial InO dose and schedule could be adjusted for tolerability and patients were allowed to receive 2 additional cycles (up to 8 total) after achieving a complete response (CR). The primary endpoint was overall response. Eighty-one patients were enrolled, among whom 48 (59%) received ≥3 InO cycles and 13 (16%) completed the treatment phase. The overall response rate was 67% (CR, 31%). Median (95% confidence interval) progression-free survival was 12·7 (8·9-26·9) months; median overall survival was not reached. Haematological adverse events (AEs) were common, particularly thrombocytopenia (74%) and neutropenia (56%). These were also the most common AEs leading to treatment discontinuation (37% and 11%, respectively); 58% of patients reported AEs leading to treatment discontinuation. InO demonstrated robust activity in these heavily pretreated patients, although treatment duration was limited by haematological toxicities. Additional studies may determine dosing regimens that allow for reduced toxicity. PMID:27101934

  19. Therapeutic effectiveness of rituximab in a patient with unresponsive autoimmune pulmonary alveolar proteinosis.

    PubMed

    Amital, Anat; Dux, Shlomo; Shitrit, David; Shpilberg, Ofer; Kramer, Mordechai R

    2010-11-01

    Pulmonary alveolar proteinosis (PAP) is a rare lung disease characterised by the accumulation of lung surfactant in the alveoli. In most cases it is an autoimmune disease with antibodies directed against the growth factor granulocyte-macrophage colony stimulating factor (GM-CSF). Standard of care consists of whole lung lavages in symptomatic patients. An alternative treatment is GM-CSF injections. The case history is reported of a patient with PAP and severe dyspnoea and hypoxaemia. Whole lung lavages and GM-CSF initially resulted in partial remission. However, the patient's condition deteriorated and her saturation during rest with high-flow oxygen treatment was 85%. The patient was treated with an anti-CD20 antibody rituximab which resulted in dramatic improvement. Room air saturation increased to 98% with exercise and she no longer required supplemental oxygen. The diffusion capacity for carbon monoxide increased from 27% to 48% of predicted and the chest x-rays improved. Rituximab may be useful in the treatment of patients with unresponsive PAP. PMID:20855439

  20. Neuromyelitis optica: Contribution of therapeutic responses markers monitoring in patients given rituximab.

    PubMed

    Romero, G; Ticchioni, M; Cohen, M; Rosenthal-Allieri, M A; Mondot, L; Lebrun Frenay, C

    2016-03-01

    Neuromyelitis optica (NMO) is a central nervous system inflammatory autoimmune disease characterized by medullary and/or optical nerve damage. It is rare but life-threatening. Concerning the treatment of NMO, many drugs have been used in background therapy. Some studies have shown efficacy of rituximab (an antiCD20 monoclonal anti-body) either on the reduction of the annual number of exacerbation or the mean score EDSS. In 2013, a Korean team reported a new protocol during which they administered rituximab only when memory B lymphocytes CD27+ were detectable in the bloodstream. In our patient, institution of this protocol led to clinical benefit with a major decrease in the EDSS score over time (7 in August 2012 vs. 1 in October 2015), a reduction of the total administered dose (4g in 2013 vs. 1.375g in 2014 vs. 0g in 2015) and side effects. Compared with the rate of theoretical administration, health expenditure savings reached 1700 Euros per month over the 11-month treatment. Monitoring therapeutic response markers with memory B lymphocyte counts appear to be an efficient cost-effective way to measure clinical efficiency, reduce total doses, and limit side effects. PMID:26915311

  1. Discovery – Development of Rituximab

    Cancer.gov

    NCI funded the development of rituximab, one of the first monoclonal antibody cancer treatments. With the discovery of rituximab, more than 70 percent of patients diagnosed with non-hodgkin lymphoma now live five years past their initial diagnosis.

  2. Favorable outcome of granulocyte colony-stimulating factor use in neuromyelitis optica patients presenting with agranulocytosis in the setting of rituximab.

    PubMed

    Mealy, Maureen A; Levy, Michael

    2015-10-15

    Neuromyelitis optica is a severe autoimmune condition affecting the central nervous system characterized by a relapsing disease course. Rituximab is a chimeric monoclonal antibody against the protein CD20, and is one of the most utilized medications for management of this disease. A known complication of rituximab use is neutropenia. We report on two patients who developed symptomatic early-onset rituximab-induced agranulocytosis who safely received granulocyte colony-stimulating factor. Neutrophil counts recovered quickly and both patients continue to receive rituximab without further incident. PMID:26439958

  3. Combined therapy with rituximab plus cyclophosphamide/vincristine/prednisone for Sjogren's syndrome-associated B-cell non-Hodgkin's lymphoma.

    PubMed

    Carbone, J; Perez-Fernandez, R; Muñoz, A; Sabin, P; Carreño, L; Fernandez-Cruz, E

    2008-02-01

    Sjogren's syndrome (SS) is characterized by an increased risk of developing non-Hodgkin's lymphoma (NHL). Optimal treatment for NHL-complicating SS is not clearly established. NHL, which expresses the CD20 antigen on tumor cell surfaces, is a disease entity candidate to treatment with anti-CD20 monoclonal antibodies. We report clinical and immunological data of a patient with SS and NHL who was treated with a regimen consisting of cyclophosphamide/vincristine/prednisone (CVP) plus rituximab. A 68-year-old women had a 26-year history of SS and autoimmune thyroiditis. The clinical course of SS was complicated with severe splenomegaly. An increased percentage of CD19+ B cells (up to 30%) was detected in peripheral blood during follow-up. Clonal rearrangement of immunoglobulin heavy chain was detected. Low-grade B marginal zone lymphoma was diagnosed (peripheral blood immunophenotype: CD19+CD20+CD23+sIg+Kappa; bone marrow immunophenotype: 25% lymphocytes; CD19+CD20+CD79A/BCL2+). She received a total of six cycles of CVP plus rituximab (375 mg/m2). Therapy was well tolerated, and B lymphocytes were depleted from the peripheral blood. Splenomegaly normalized. No evidence of neoplastic infiltration was detected in bone marrow after completion of therapy, while certain symptoms of SS (sicca and arthralgia) improved with treatment. CVP plus rituximab proved effective in a patient with SS with NHL. PMID:18270861

  4. Improved outcome of adult Burkitt lymphoma/leukemia with rituximab and chemotherapy: report of a large prospective multicenter trial

    PubMed Central

    Walewski, Jan; Döhner, Hartmut; Viardot, Andreas; Hiddemann, Wolfgang; Spiekermann, Karsten; Serve, Hubert; Dührsen, Ulrich; Hüttmann, Andreas; Thiel, Eckhard; Dengler, Jolanta; Kneba, Michael; Schaich, Markus; Schmidt-Wolf, Ingo G. H.; Beck, Joachim; Hertenstein, Bernd; Reichle, Albrecht; Domanska-Czyz, Katarzyna; Fietkau, Rainer; Horst, Heinz-August; Rieder, Harald; Schwartz, Stefan; Burmeister, Thomas; Gökbuget, Nicola

    2014-01-01

    This largest prospective multicenter trial for adult patients with Burkitt lymphoma/leukemia aimed to prove the efficacy and feasibility of short-intensive chemotherapy combined with the anti-CD20 antibody rituximab. From 2002 to 2011, 363 patients 16 to 85 years old were recruited in 98 centers. Treatment consisted of 6 5-day chemotherapy cycles with high-dose methotrexate, high-dose cytosine arabinoside, cyclophosphamide, etoposide, ifosphamide, corticosteroids, and triple intrathecal therapy. Patients >55 years old received a reduced regimen. Rituximab was given before each cycle and twice as maintenance, for a total of 8 doses. The rate of complete remission was 88% (319/363); overall survival (OS) at 5 years, 80%; and progression-free survival, 71%; with significant difference between adolescents, adults, and elderly patients (OS rate of 90%, 84%, and 62%, respectively). Full treatment could be applied in 86% of the patients. The most important prognostic factors were International Prognostic Index (IPI) score (0-2 vs 3-5; P = .0005), age-adjusted IPI score (0-1 vs 2-3; P = .0001), and gender (male vs female; P = .004). The high cure rate in this prospective trial with a substantial number of participating hospitals demonstrates the efficacy and feasibility of chemoimmunotherapy, even in elderly patients. This trial was registered at www.clinicaltrials.gov as #NCT00199082. PMID:25359988

  5. An approach for conjugation of 177Lu- DOTA-SCN- Rituximab (BioSim) & its evaluation for radioimmunotherapy of relapsed & refractory B-cell non Hodgkins lymphoma patients

    PubMed Central

    Thakral, Parul; Singla, Suhas; Yadav, Madhav Prasad; Vasisht, Atul; Sharma, Atul; Gupta, Santosh Kumar; Bal, C.S.; Snehlata; Malhotra, Arun

    2014-01-01

    Background & objectives: The prerequisite of radioimmunotherapy is stable binding of a radionuclide to monoclonal antibodies, which are specific to the tumour-associated antigen. Most B-cell lymphomas express CD20 antigen on the surface of the tumour cells, making it a suitable target for therapeutic radioactive monoclonal antibodies. In the present study, the immunoconjugate of biosimilar Rituximab (Reditux™) and macrocyclic chelator, p-SCN-Bz-DOTA, was prepared and radiolabelled with Lutetium-177 followed by quality control procedures. Methods: Rituximab(BioSim) was desalted with sodium bicarbonate (0.1M, pH 9.0) and incubated with DOTA-SCN (1:50). The effectiveness of the conjugation was evaluated by determining the number of chelators per antibody molecule. This conjugate was radiolabelled with Lutetium-177 and purified using PD10 column. The quality control parameters like pH, clarity, radiochemical purity, in vitro stability and sterility were studied. Immunoreactivity of 177Lu-DOTA-Rituximab (BioSim) was assessed using RAMOS cells. The radioimmunoconjugate (RIC) after stringent quality assurance was injected in three patients and the biodistribution profile was analysed. Results: An average of 4.25 ± 1.04 p-SCN-Bz-DOTA molecules could be randomly conjugated to a single molecule of Rituximab (BioSim). The radiochemical purity of the labelled antibody was > 95 per cent with preserved affinity for CD20 antigen. The final preparation was stable up to about 120 h when tested under different conditions. A favourable biodistribution profile was observed with liver showing the maximum uptake of the RIC. Interpretation & conclusions: A favourable radiochemical purity, stability and biodistribution of the radiolabelled immunoconjugate indicate that clinical trials for evaluation of toxicity and efficacy of 177Lu-DOTA-antiCD20 antibody-Rituximab (BioSim) in patients of relapsed and refractory non Hodgkin's lymphoma can be considered. PMID:24927340

  6. B-Lymphocyte Depletion in Myalgic Encephalopathy/ Chronic Fatigue Syndrome. An Open-Label Phase II Study with Rituximab Maintenance Treatment

    PubMed Central

    Fluge, Øystein; Risa, Kristin; Lunde, Sigrid; Alme, Kine; Rekeland, Ingrid Gurvin; Sapkota, Dipak; Kristoffersen, Einar Kleboe; Sørland, Kari; Bruland, Ove; Dahl, Olav; Mella, Olav

    2015-01-01

    Background Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We previously reported a pilot case series followed by a small, randomized, placebo-controlled phase II study, suggesting that B-cell depletion using the monoclonal anti-CD20 antibody rituximab can yield clinical benefit in ME/CFS. Methods In this single-center, open-label, one-armed phase II study (NCT01156909), 29 patients were included for treatment with rituximab (500 mg/m2) two infusions two weeks apart, followed by maintenance rituximab infusions after 3, 6, 10 and 15 months, and with follow-up for 36 months. Findings Major or moderate responses, predefined as lasting improvements in self-reported Fatigue score, were detected in 18 out of 29 patients (intention to treat). Clinically significant responses were seen in 18 out of 28 patients (64%) receiving rituximab maintenance treatment. For these 18 patients, the mean response durations within the 156 weeks study period were 105 weeks in 14 major responders, and 69 weeks in four moderate responders. At end of follow-up (36 months), 11 out of 18 responding patients were still in ongoing clinical remission. For major responders, the mean lag time from first rituximab infusion until start of clinical response was 23 weeks (range 8–66). Among the nine patients from the placebo group in the previous randomized study with no significant improvement during 12 months follow-up after saline infusions, six achieved a clinical response before 12 months after rituximab maintenance infusions in the present study. Two patients had an allergic reaction to rituximab and two had an episode of uncomplicated late-onset neutropenia. Eight patients experienced one or more transient symptom flares after rituximab infusions. There was no unexpected toxicity. Conclusion In a subgroup of ME/CFS patients, prolonged B-cell depletion with rituximab maintenance infusions was associated with sustained clinical responses. The observed

  7. Clinical efficacy of combined rituximab treatment in a woman with severe Graves' ophthalmopathy

    PubMed Central

    Liu, Xiaomei; Guo, Hui; Liu, Juan; Shi, Bingyin

    2016-01-01

    The present study reports the case of a female Chinese patient with Graves' disease (GD) and severe Graves' ophthalmopathy (GO) in its active phase, who was treated with propylthiouracil and oral prednisolone for 2 months at a local hospital. However, a lack of improvement in symptoms meant that the patient was transferred to the First Affiliated Hospital of Xi'an Jiaotong University (Xi'an, China), whereupon the patient received high-dose intravenous methylprednisolone pulse therapy, although with limited efficacy. Subsequently, rituximab (RTX; anti-CD20 monoclonal antibody) combined with orbital irradiation treatment was initiated. The patient responded positively to the combined treatment; the clinical symptoms and enlargement of the extraocular muscles were ameliorated, and there were marked decreases in the clinical activity and NOSPECS grading scores. Furthermore, the serum levels of anti-thyrotropin receptor antibodies (TRAb) were markedly decreased at 2 months following RTX therapy. The patient was maintained in a euthyroid state by treatment with methimazole during and following RTX therapy. It was concluded that RTX treatment may attenuate severe GO by depleting lymphocytes, and may promote the recovery of GD by reducing the serum levels of TRAb. PMID:27446325

  8. Lenalidomide plus Rituximab as Initial Treatment for Mantle-Cell Lymphoma

    PubMed Central

    Ruan, Jia; Martin, Peter; Shah, Bijal; Schuster, Stephen J.; Smith, Sonali M.; Furman, Richard R.; Christos, Paul; Rodriguez, Amelyn; Svoboda, Jakub; Lewis, Jessica; Katz, Orel; Coleman, Morton; Leonard, John P.

    2015-01-01

    BACKGROUND Mantle-cell lymphoma is generally incurable. Initial treatment is not standardized but usually includes cytotoxic chemotherapy. Lenalidomide, an immunomodulatory compound, and rituximab, an anti-CD20 antibody, are active in patients with recurrent mantle-cell lymphoma. We evaluated lenalidomide plus rituximab as a first-line therapy. METHODS We conducted a single-group, multicenter, phase 2 study with induction and maintenance phases. During the induction phase, lenalidomide was administered at a dose of 20 mg daily on days 1 through 21 of every 28-day cycle for 12 cycles; the dose was escalated to 25 mg daily after the first cycle if no dose-limiting adverse events occurred during the first cycle and was reduced to 15 mg daily during the maintenance phase. Rituximab was administered once weekly for the first 4 weeks and then once every other cycle until disease progression. The primary end point was the overall response rate. Secondary end points included outcomes related to safety, survival, and quality of life. RESULTS A total of 38 participants were enrolled at four centers from July 2011 through April 2014. The median age was 65 years. On the basis of the Mantle Cell Lymphoma International Prognostic Index scores, the proportions of participants with low-risk, intermediate-risk, and high-risk disease at baseline were similar (34%, 34%, and 32%, respectively). The most common grade 3 or 4 adverse events were neutropenia (in 50% of the patients), rash (in 29%), thrombocytopenia (in 13%), an inflammatory syndrome (“tumor flare”) (in 11%), anemia (in 11%), serum sickness (in 8%), and fatigue (in 8%). At the median follow-up of 30 months (through February 2015), the overall response rate among the participants who could be evaluated was 92% (95% confidence interval [CI], 78 to 98), and the complete response rate was 64% (95% CI, 46 to 79); median progression-free survival had not been reached. The 2-year progression-free survival was estimated to be

  9. Gemcitabine enhances rituximab-mediated complement-dependent cytotoxicity to B cell lymphoma by CD20 upregulation.

    PubMed

    Hayashi, Kazumi; Nagasaki, Eijiro; Kan, Shin; Ito, Masaki; Kamata, Yuko; Homma, Sadamu; Aiba, Keisuke

    2016-05-01

    Although rituximab, a chimeric monoclonal antibody that specifically binds to CD20, has significantly improved the prognosis for diffuse large B cell lymphoma (DLBCL), one-third of DLBCL patients demonstrate resistance to rituximab or relapse after rituximab treatment. Thus, a novel approach to rituximab-based treatment is likely to be required to improve the efficacy of DLBCL treatment. As complement dependent cytotoxicity (CDC) is a key mechanism mediating rituximab's tumoricidal activity, rituximab binding to CD20 on tumor cells is a critical factor for effective rituximab-based treatments against DLBCL. We found that gemcitabine (GEM), but not lenalidomide (LEN) or azacitidine (AZA), can upregulate CD20 expression in TK and KML-1 cells, two human DLBCL cell lines. Treatment of TK and KML-1 cells with GEM enhanced CD20 expression at both the mRNA and protein levels. CD20 upregulation by GEM treatment was accompanied by increased rituximab binding to CD20. In TK cells, GEM treatment synergistically increased rituximab-mediated CDC activity in a dose-dependent manner. In KML cells, GEM treatment also induced upregulation of complement regulatory proteins, possibly leading to resistance to CDC. Treatment with LEN, a drug that did not upregulate CD20, did not enhance rituximab-mediated CDC activity. GEM treatment activated nuclear factor-kappa B (NF-kB) signaling in these cells. Furthermore, a specific inhibitor to NF-kB suppressed GEM-induced CD20 upregulation, indicating that GEM-induced NF-kB activation is closely associated with CD20 upregulation. These results suggest that when used in combination, GEM might enhance the antitumor efficacy of rituximab against DLBCL due to its unique ability to upregulate CD20. PMID:26920337

  10. A Study of Rituximab and Ifosfamide, Carboplatin, and Etoposide Chemotherapy in Children with Recurrent/Refractory B-cell (CD20+) Non-Hodgkin Lymphoma and Mature B-Cell Acute Lymphoblastic Leukemia: A Report from the Children's Oncology Group

    PubMed Central

    Griffin, Timothy C.; Weitzman, Sheila; Weinstein, Howard; Chang, Myron; Cairo, Mitchell; Hutchison, Robert; Shiramizu, Bruce; Wiley, Joseph; Woods, Deborah; Barnich, Margaret; Gross, Thomas G.

    2009-01-01

    Background To estimate the response rate and therapy related toxicities of the anti-CD20 monoclonal antibody rituximab when combined with chemotherapy including ifosfamide, carboplatin, and etoposide (ICE) in patients with relapsed and refractory B-cell non-Hodgkin lymphoma and mature B-cell acute lymphoblastic leukemia (B-ALL). Methods Patients received rituximab and ICE for 1 to 3 cycles, depending upon response. Rituximab (375 mg/m2) was given on day 1 and 3 of each cycle (day 1 only for cycle 3), with ifosfamide (3000 mg/m2) and etoposide (100 mg/m2) given on days 3, 4, and 5 and carboplatin (635 mg/m2) given on day 3 only. Results Twenty-one patients were enrolled, of whom 20 were eligible and evaluable. Although hematologic toxicities were common, only one patient was removed from study due to prolonged myelosuppression. Toxicities related to infusions of rituximab were frequent but manageable. Of the 6 eligible patients with diffuse large B-cell lymphoma, 3 achieved complete remission (CR), 1 had stable disease (SD), and 2 had progressive disease (PD). Of the 14 eligible patients with Burkitt lymphoma and B-ALL, there were 4 complete responses (CR), 5 partial responses (PR), 1 SD and 4 with PD. Thus the CR/PR rate for the entire group was 12/20 (60%). Following completion of protocol therapy 6 patients were able to proceed to consolidation with high-dose therapy and stem cell rescue. Conclusions The combination of rituximab and ICE chemotherapy was associated with an encouraging objective response rate and an acceptable toxicity profile. PMID:18816698

  11. Practical considerations on the use of rituximab in autoimmune neurological disorders

    PubMed Central

    Kosmidis, Mixalis L.; Dalakas, Marinos C.

    2010-01-01

    Rituximab (Mabthera, Rituxan) is a chimeric human/murine monoclonal antibody against CD-20 surface antigen expressed on B-cells. Rituximab, by causing B-cell depletion, appears to be effective in several autoimmune disorders; it has been approved for rheumatoid arthritis and is a promising new agent in the treatment of several autoimmune neurological disorders. A controlled study in patients with relapsing remitting multiple sclerosis has shown that rituximab significantly reduces the number of new MRI lesions and improves clinical outcome; it also showed some promise in a subset of patients with primary progressive MS. The drug is also effective in a number of patients with Devic’s disease, myasthenia gravis, autoimmune neuropathies, and inflammatory myopathies. The apparent effectiveness of rituximab has moved B-cells into the center stage of clinical and laboratory investigation of autoimmune neurological disorders. We review the evidence-based effectiveness of rituximab in neurological disorders based on controlled trials and anecdotal reports, including our own experience, and address the immunobiology of B-cells in autoimmune central nervous system (CNS) and peripheral nervous system (PNS) disorders. In addition, we provide practical guidelines on how best to use this drug in clinical practice and highlight its potential toxicity. PMID:21179602

  12. Persistence and selection of an expanded B-cell clone in the setting of rituximab therapy for Sjögren’s syndrome

    PubMed Central

    2014-01-01

    Introduction Subjects with primary Sjögren’s syndrome (SjS) have an increased risk of developing B-cell lymphoma and may harbor monoclonal B-cell expansions in the peripheral blood. Expanded B-cell clones could be pathogenic, and their persistence could exacerbate disease or predispose toward the development of lymphoma. Therapy with anti-CD20 (rituximab) has the potential to eliminate expanded B-cell clones and thereby potentially ameliorate disease. This study was undertaken to identify and track expanded B-cell clones in the blood of subjects with primary SjS who were treated with rituximab. Methods To determine whether circulating B-cell clones in subjects with primary SjS emerge or remain after B cell-depleting therapy with rituximab, we studied the antibody heavy-chain repertoire. We performed single-memory B-cell and plasmablast sorting and antibody heavy-chain sequencing in six rituximab-treated SjS subjects over the course of a 1-year follow-up period. Results Expanded B-cell clones were identified in four out of the six rituximab-treated SjS subjects, based upon the independent amplification of sequences with identical or highly similar VH, DH, and JH gene segments. We identified one SjS subject with a large expanded B-cell clone that was present prior to therapy and persisted after therapy. Somatic mutations in the clone were numerous but did not increase in frequency over the course of the 1-year follow-up, suggesting that the clone had been present for a long period of time. Intriguingly, a majority of the somatic mutations in the clone were silent, suggesting that the clone was under chronic negative selection. Conclusions For some subjects with primary SjS, these data show that (a) expanded B-cell clones are readily identified in the peripheral blood, (b) some clones are not eliminated by rituximab, and (c) persistent clones may be under chronic negative selection or may not be antigen-driven. The analysis of sequence variation among members of an

  13. High titers of anti-HBs prevent rituximab-related viral reactivation in resolved hepatitis B patient with non-Hodgkin's lymphoma.

    PubMed

    Cho, Yuri; Yu, Su Jong; Cho, Eun Ju; Lee, Jeong-Hoon; Kim, Tae Min; Heo, Dae Seog; Kim, Yoon Jun; Yoon, Jung-Hwan

    2016-06-01

    Rituximab, an anti-CD20 monoclonal antibody, is associated with an increased risk of hepatitis B virus (HBV) reactivation. This study aimed to determine the predictive factors for rituximab-related HBV reactivation in resolved hepatitis B patients, defined as HBsAg-negative, anti-HBc-positive, and undetectable HBV DNA. Among 840 consecutive patients with CD20-positive B-cell lymphoma who received rituximab-based chemotherapy from 2003 through 2014 at Seoul National University Hospital, 732 patients were excluded because either anti-HBc was not assessed or they were HBsAg-seropositive. This retrospective study included 108 resolved hepatitis B patients. During a median 33.5-month follow-up period, eight cases of HBV reactivation occurred only among the patients with low anti-HBs titers (<100 mIU/ml) at baseline and those who did not receive antiviral prophylaxis. Using multivariate analyses, antiviral prophylaxis and baseline anti-HBs titers were the protective factors for HBV reactivation (hazard ratio [HR], 0.90 and 0.95, respectively). Among those who did not receive antiviral prophylaxis, patients with high baseline anti-HBs (≥100 mIU/ml) experienced significantly lower risk of HBV reactivation (HR, 0.49; P = 0.006) than the patients with low baseline anti-HBs (<100 mIU/ml) whose cumulative HBV reactivation rates at 6 and 24 months after chemotherapy were 8.3% and 17.3%, respectively. High anti-HBs titer at baseline and antiviral prophylaxis prevented HBV reactivation, suggesting antiviral prophylaxis should be considered according to baseline anti-HBs titer. Meticulous follow-up for ALT and HBV DNA without antiviral prophylaxis might be possible for the patients with high baseline anti-HBs (≥100 mIU/ml). J. Med. Virol. 88:1010-1017, 2016. © 2015 Wiley Periodicals, Inc. PMID:26531242

  14. Targeting intratumoral B cells with rituximab in addition to CHOP in angioimmunoblastic T-cell lymphoma. A clinicobiological study of the GELA

    PubMed Central

    Delfau-Larue, Marie-Hélène; de Leval, Laurence; Joly, Bertrand; Plonquet, Anne; Challine, Dominique; Parrens, Marie; Delmer, Alain; Salles, Gilles; Morschhauser, Franck; Delarue, Richard; Brice, Pauline; Bouabdallah, Reda; Casasnovas, Olivier; Tilly, Hervé; Gaulard, Philippe; Haioun, Corinne

    2012-01-01

    Background In angioimmunoblastic T-cell lymphoma, symptoms linked to B-lymphocyte activation are common, and variable numbers of CD20+ large B-blasts, often infected by Epstein-Barr virus, are found in tumor tissues. We postulated that the disruption of putative B-T interactions and/or depletion of the Epstein-Barr virus reservoir by an anti-CD20 monoclonal antibody (rituximab) could improve the clinical outcome produced by conventional chemotherapy. Design and Methods Twenty-five newly diagnosed patients were treated, in a phase II study, with eight cycles of rituximab + chemotherapy (R-CHOP21). Tumor infiltration, B-blasts and Epstein-Barr virus status in tumor tissue and peripheral blood were fully characterized at diagnosis and were correlated with clinical outcome. Results A complete response rate of 44% (95% CI, 24% to 65%) was observed. With a median follow-up of 24 months, the 2-year progression-free survival rate was 42% (95% CI, 22% to 61%) and overall survival rate was 62% (95% CI, 40% to 78%). The presence of Epstein-Barr virus DNA in peripheral blood mononuclear cells (14/21 patients) correlated with Epstein-Barr virus score in lymph nodes (P<0.004) and the detection of circulating tumor cells (P=0.0019). Despite peripheral Epstein-Barr virus clearance after treatment, the viral load at diagnosis (>100 copy/μg DNA) was associated with shorter progression-free survival (P=0.06). Conclusions We report here the results of the first clinical trial targeting both the neoplastic T cells and the microenvironment-associated CD20+ B lymphocytes in angioimmunoblastic T-cell lymphoma, showing no clear benefit of adding rituximab to conventional chemotherapy. A strong relationship, not previously described, between circulating Epstein-Barr virus and circulating tumor cells is highlighted. PMID:22371178

  15. Assessment of physicochemical properties of rituximab related to its immunomodulatory activity.

    PubMed

    Miranda-Hernández, Mariana P; López-Morales, Carlos A; Ramírez-Ibáñez, Nancy D; Piña-Lara, Nelly; Pérez, Nestor O; Molina-Pérez, Aarón; Revilla-Beltri, Jorge; Flores-Ortiz, Luis F; Medina-Rivero, Emilio

    2015-01-01

    Rituximab is a chimeric monoclonal antibody employed for the treatment of CD20-positive B-cell non-Hodgkin's lymphoma, chronic lymphocytic leukemia, rheumatoid arthritis, granulomatosis with polyangiitis and microscopic polyangiitis. It binds specifically to the CD20 antigen expressed on pre-B and consequently on mature B-lymphocytes of both normal and malignant cells, inhibiting their proliferation through apoptosis, CDC, and ADCC mechanisms. The immunomodulatory activity of rituximab is closely related to critical quality attributes that characterize its chemical composition and spatial configuration, which determine the recognition of CD20 and the binding to receptors or factors involved in its effector functions, while regulating the potential immunogenic response. Herein, we present a physicochemical and biological characterization followed by a pharmacodynamics and immunogenicity study to demonstrate comparability between two products containing rituximab. The physicochemical and biological characterization revealed that both products fit within the same response intervals exhibiting the same degree of variability. With regard to clinical response, both products depleted CD20+ B-cells until posttreatment recovery and no meaningful differences were found in their pharmacodynamic profiles. The evaluation of anti-chimeric antibodies did not show differential immunogenicity among products. Overall, these data confirm that similarity of critical quality attributes results in a comparable immunomodulatory activity. PMID:25973441

  16. Assessment of Physicochemical Properties of Rituximab Related to Its Immunomodulatory Activity

    PubMed Central

    Miranda-Hernández, Mariana P.; López-Morales, Carlos A.; Ramírez-Ibáñez, Nancy D.; Piña-Lara, Nelly; Pérez, Nestor O.; Molina-Pérez, Aarón; Revilla-Beltri, Jorge; Flores-Ortiz, Luis F.

    2015-01-01

    Rituximab is a chimeric monoclonal antibody employed for the treatment of CD20-positive B-cell non-Hodgkin's lymphoma, chronic lymphocytic leukemia, rheumatoid arthritis, granulomatosis with polyangiitis and microscopic polyangiitis. It binds specifically to the CD20 antigen expressed on pre-B and consequently on mature B-lymphocytes of both normal and malignant cells, inhibiting their proliferation through apoptosis, CDC, and ADCC mechanisms. The immunomodulatory activity of rituximab is closely related to critical quality attributes that characterize its chemical composition and spatial configuration, which determine the recognition of CD20 and the binding to receptors or factors involved in its effector functions, while regulating the potential immunogenic response. Herein, we present a physicochemical and biological characterization followed by a pharmacodynamics and immunogenicity study to demonstrate comparability between two products containing rituximab. The physicochemical and biological characterization revealed that both products fit within the same response intervals exhibiting the same degree of variability. With regard to clinical response, both products depleted CD20+ B-cells until posttreatment recovery and no meaningful differences were found in their pharmacodynamic profiles. The evaluation of anti-chimeric antibodies did not show differential immunogenicity among products. Overall, these data confirm that similarity of critical quality attributes results in a comparable immunomodulatory activity. PMID:25973441

  17. A review of the current use of rituximab in autoimmune diseases.

    PubMed

    Gürcan, Hakan M; Keskin, Derin B; Stern, Joel N H; Nitzberg, Matthew A; Shekhani, Haris; Ahmed, A Razzaque

    2009-01-01

    Rituximab is a human/murine chimeric monoclonal antibody primarily used for treating non-Hodgkin's B-cell lymphoma. Recently it has also been used in the treatment of several autoimmune diseases. A literature review was conducted to determine the efficacy of rituximab in the treatment of some of these autoimmune diseases. Multiple mechanisms proposed for the rituximab mediated B cell depletion are also discussed. The efficacy of rituximab is well-established and it is FDA approved for treatment of Rheumatoid arthritis. In this review, data on the use of rituximab is presented from 92 studies involving 1197 patients with the following diseases: systemic lupus erythematosus, idiopathic thrombocytopenic purpura, anti-neutrophil cytoplasmic antibody associated vasculitis, Grave's disease, autoimmune hemolytic anemia, pemphigus vulgaris, hemophilia A, cold agglutinin disease, Sjogren's syndrome, graft vs. host disease, thrombotic thrombocytopenic purpura, cryoglobulinemia, IgM mediated neuropathy, multiple sclerosis, neuromyelitis optica, idiopathic membranous nephropathy, dermatomyositis, and opsoclonus myoclonus. The efficacy varies among different autoimmune diseases. The cumulative data would suggest that in the vast majority of studies in this review, RTX has a beneficial role in their treatment. While rituximab is very effective in the depletion of B cells, current research suggests it may also influence other cells of the immune system by re-establishing immune homeostasis and tolerance. The safety profile of RTX reveals that most reactions are infusion related. In patients with autoimmune diseases the incidence of serious and severe side effects is low. Systemic infection still remains a major concern and may result in death. PMID:19000786

  18. Interleukin (IL)-17-producing pathogenic T lymphocytes co-express CD20 and are depleted by rituximab in primary Sjögren's syndrome: a pilot study.

    PubMed

    Alunno, A; Carubbi, F; Bistoni, O; Caterbi, S; Bartoloni, E; Di Benedetto, P; Cipriani, P; Giacomelli, R; Gerli, R

    2016-06-01

    Compelling evidence suggests that interleukin (IL)-17 and IL-17-producing cells play a pivotal role in the pathogenesis of primary Sjögren's syndrome (pSS). We investigated phenotypical and functional effects of the anti-CD20 antibody rituximab (RTX) on circulating and glandular IL-17-producing T cells in pSS. RTX is able to deplete glandular IL-17(+) CD3(+) CD4(-) CD8(-) double-negative (DN) and CD4(+) Th17 cells as well as circulating IL-17(+) DN T cells. A fraction of glandular and circulating IL-17(+) DN cells and CD4(+) T helper type 17 (Th17) cells co-expresses CD20 on the cell surface explaining, at least in part, such depletive capacity of RTX. The exposure to RTX does not rescue the in-vitro corticosteroid resistance of IL-17(+) DN T cells. Our results support further the therapeutic role in pSS of RTX that, despite its B cell specificity, appears able to also hamper IL-17-producing T cells in this disease. PMID:26814615

  19. Rituximab-induced neutropenia in a patient with inflammatory myopathy and systemic sclerosis overlap disease

    PubMed Central

    Roberts, Mark; Oddis, Chester; Herrick, Arianne; Chinoy, Hector

    2016-01-01

    Rituximab (RTX) is a monoclonal chimeric antibody directed against the CD20 antigen of B lymphocytes. Late onset neutropenia (LON) is a recognised complication of rituximab usually occurring 4 weeks after the last dose and is reported in both haematological and rheumatological conditions. However, it has never been described in a patient with myositis and systemic sclerosis overlap disease. We describe a case of LON in a 54-year-old man who was diagnosed with myositis and then systemic sclerosis overlap disease. It resolved within 7 days, and the patient did not suffer neutropenic sepsis or any other complications. We propose similar mechanisms for LON as described in other conditions and routine blood monitoring in such patients. PMID:27407275

  20. Iodine-131 Tositumomab: (131)I-anti-B1 antibody, (131)I-tositumomab, anti-CD20 murine monoclonal antibody-I-131, B1, Bexxar, (131)I-anti-B1 antibody, iodine-131 tositumomab, iodine-131 anti-B1 antibody, tositumomab.

    PubMed

    2003-01-01

    combination with CHOP chemotherapy is underway in the US as first-line therapy in patients with intermediate-grade NHL. Corixa Corporation has initiated a phase II trial of iodine-131 tositumomab in combination with cyclophosphamide, vincristine and prednisone for the treatment of previously untreated low-grade NHL. The trial was initiated while the company was preparing its BLA for Bexxar for use as a single agent for relapsed or refractory NHL. Corixa Corporation intends to pursue additional trials to expand the potential use of iodine-131 tositumomab to other indications, including chronic lymphocytic leukaemia. The agent is also in a clinical trial for preparation in autologous bone marrow transplant patients. The trial is designed to test the combination of iodine-131 tositumomab and chemotherapy. The trial began in 1995 and has so far enrolled 40 patients. In addition, a phase II dose-escalation trial has begun at the University of Nebraska for the combined use of iodine-131 tositumomab and chemotherapy as preparation for autologous bone marrow transplant. Corixa Corporation has received an issued US patent covering methods for administering and dosing radioimmunotherapy for the treatment of B-cell lymphomas. The patent covers iodine-131 tositumomab and other anti-CD20 antibodies used to aid in selective tumour targeting. Corixa Corporation has exclusive rights to the patent.A February 2000 media release from GlaxoSmithKline and Corixa Corporation stated that they had been issued a composition patent relating to radiolabelled monoclonal antibodies (including Bexxar) for the treatment of B-cell lymphomas. On 11 September 2001, IDEC announced that it had filed two separate lawsuits. The first lawsuit is against Corixa Corporation and the University of Michigan on six patents pertaining to products and processes related to radioimmunotherapy. They seek a declaration that Zevalin does not infringe Corixa Corporation's issued US patents. The second lawsuit involves two

  1. Electroejaculation of chimeric rats

    PubMed Central

    McCoy, Marina R.; Montonye, Daniel; Bryda, Elizabeth C.

    2014-01-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats using light gas anesthesia and a custom-made platform for sperm collection. PMID:23689457

  2. Electroejaculation of chimeric rats.

    PubMed

    McCoy, Marina R; Montonye, Daniel; Bryda, Elizabeth C

    2013-06-01

    With the advent of genetic engineering of rodents came the need to assess fertility and germline competency, especially in chimeric rodents generated using embryonic stem cells. Traditional methods rely on natural mating and progeny testing, which is time- and cost-intensive. Electroejaculation is a faster method of collecting sperm for genetic analysis and offers the additional benefit of using fewer animals. This column describes a refined electroejaculation technique for chimeric rats using light gas anesthesia and a custom-made platform for sperm collection. PMID:23689457

  3. Vulvovaginal pyoderma gangrenosum secondary to rituximab therapy.

    PubMed

    Dixit, Shreya; Selva-Nayagam, Priya; Hamann, Ian; Fischer, Gayle

    2015-01-01

    Rituximab is being used increasingly for the treatment of B-cell malignancies and nonmalignant conditions. Pyoderma gangrenosum is a rare neutrophilic dermatosis, which can be either idiopathic or associated with underlying systemic inflammatory conditions. We present a series of 4 patients who presented with ulcerative pyoderma gangrenosum in the vulvovaginal area after treatment with rituximab. PMID:24769650

  4. Chimeric Pestivirus Experimental Vaccines.

    PubMed

    Reimann, Ilona; Blome, Sandra; Beer, Martin

    2016-01-01

    Chimeric pestiviruses have shown great potential as marker vaccine candidates against pestiviral infections. Exemplarily, we describe here the construction and testing of the most promising classical swine fever vaccine candidate "CP7_E2alf" in detail. The description is focused on classical cloning technologies in combination with reverse genetics. PMID:26458840

  5. Rituximab in immunologic glomerular diseases

    PubMed Central

    Ejaz, A Ahsan; Asmar, Abdo; Alsabbagh, Mourad M

    2012-01-01

    Experimental data suggest that the B-cell antigen CD20 may play a significant role in the pathogenesis of many diseases including glomerular diseases. These and other findings underpin the central concept of B-cell-depleting therapies that target CD20 antigen as treatments for lupus nephritis, idiopathic membranous nephropathy, focal segmental glomerulosclerosis, cryglobulinemic glomerulonephritis, antibody mediated renal allograft rejection and recurrent glomerulonephritis in renal allograft. Use of rituximab as a B-cell depleting therapy has been associated with clinical improvement and has emerged as a possible adjunct or alternative treatment option in this field of nephrology. PMID:22377738

  6. Preclinical safety, pharmacokinetics, pharmacodynamics, and biodistribution studies with Ad35K++ protein: a novel rituximab cotherapeutic

    PubMed Central

    Richter, Maximilian; Yumul, Roma; Saydaminova, Kamola; Wang, Hongjie; Gough, Michael; Baldessari, Audrey; Cattaneo, Roberto; Lee, Frank; Wang, Chung-Huei Katherine; Jang, Haishan; Astier, Anne; Gopal, Ajay; Carter, Darrick; Lieber, André

    2016-01-01

    Rituximab is a mouse/human chimeric monoclonal antibody targeted toward CD20. It is efficient as first-line therapy of CD20-positive B-cell malignancies. However, a large fraction of treated patients relapse with rituximab-resistant disease. So far, only modest progress has been made in treatment options for rituximab refractory patients. One of the mechanisms for rituximab resistance involves the upregulation of CD46, which is a key cell surface protein that blocks the activation of complement. We have recently developed a technology that depletes CD46 from the cell surface and thereby sensitizes tumor cells to complement-dependent cytotoxicity. This technology is based on a small recombinant protein, Ad35K++ that binds with high affinity to CD46. In preliminary studies using a 6 × histidinyl tagged protein, we had demonstrated that intravenous Ad35K++ injection in combination with rituximab was safe and increased rituximab-mediated killing of CD20-positive target cells in mice and nonhuman primates (NHPs). The presence of the tag, while allowing for easy purification by Ni-NTA chromatography, has the potential to increase the immunogenicity of the recombinant protein. For clinical application, we therefore developed an Ad35K++ protein without His-tag. In the present study, we performed preclinical studies in two animal species (mice and NHPs) with this protein demonstrating its safety and efficacy. These studies estimated the Ad35K++ dose range and treatment regimen to be used in patients. Furthermore, we showed that intravenous Ad35K++ injection triggers the shedding of the CD46 extracellular domain in xenograft mouse tumor models and in macaques. Shed serum CD46 can be measured in the serum and can potentially be used as a pharmacodynamic marker for monitoring Ad35K++ activity in patient undergoing treatment with this agent. These studies create the basis for an investigational new drug application for the use of Ad35K++ in combination with rituximab in the

  7. Preclinical safety, pharmacokinetics, pharmacodynamics, and biodistribution studies with Ad35K++ protein: a novel rituximab cotherapeutic.

    PubMed

    Richter, Maximilian; Yumul, Roma; Saydaminova, Kamola; Wang, Hongjie; Gough, Michael; Baldessari, Audrey; Cattaneo, Roberto; Lee, Frank; Wang, Chung-Huei Katherine; Jang, Haishan; Astier, Anne; Gopal, Ajay; Carter, Darrick; Lieber, André

    2016-01-01

    Rituximab is a mouse/human chimeric monoclonal antibody targeted toward CD20. It is efficient as first-line therapy of CD20-positive B-cell malignancies. However, a large fraction of treated patients relapse with rituximab-resistant disease. So far, only modest progress has been made in treatment options for rituximab refractory patients. One of the mechanisms for rituximab resistance involves the upregulation of CD46, which is a key cell surface protein that blocks the activation of complement. We have recently developed a technology that depletes CD46 from the cell surface and thereby sensitizes tumor cells to complement-dependent cytotoxicity. This technology is based on a small recombinant protein, Ad35K++ that binds with high affinity to CD46. In preliminary studies using a 6 × histidinyl tagged protein, we had demonstrated that intravenous Ad35K++ injection in combination with rituximab was safe and increased rituximab-mediated killing of CD20-positive target cells in mice and nonhuman primates (NHPs). The presence of the tag, while allowing for easy purification by Ni-NTA chromatography, has the potential to increase the immunogenicity of the recombinant protein. For clinical application, we therefore developed an Ad35K++ protein without His-tag. In the present study, we performed preclinical studies in two animal species (mice and NHPs) with this protein demonstrating its safety and efficacy. These studies estimated the Ad35K++ dose range and treatment regimen to be used in patients. Furthermore, we showed that intravenous Ad35K++ injection triggers the shedding of the CD46 extracellular domain in xenograft mouse tumor models and in macaques. Shed serum CD46 can be measured in the serum and can potentially be used as a pharmacodynamic marker for monitoring Ad35K++ activity in patient undergoing treatment with this agent. These studies create the basis for an investigational new drug application for the use of Ad35K++ in combination with rituximab in the

  8. Characterization of Self-Assembled Monolayers of Peptide Mimotopes of CD20 Antigen and Their Binding with Rituximab.

    PubMed

    Leo, Norman; Shang, Yuqin; Yu, Jing-jiang; Zeng, Xiangqun

    2015-12-29

    CD20, expressed in greater than 90% of B-lymphocytic lymphomas, is a target for antibody therapy. Rituximab is a chimeric therapeutic monoclonal antibody (mAb) against the protein CD20, allowing it to destroy B cells and to treat lymphoma, leukemia, transplant rejection, and autoimmune disorder. In this work, the binding of rituximab to self-assembled monolayers (SAMs) of peptide mimotopes of CD20 antigen was systematically characterized. Four peptide mimotopes of CD 20 antigen were selected from the literature and redesigned to allow their SAM immobilizations on gold electrodes through a peptide linker with cysteine. The bindings of these peptides with rituximab and control mAbs (trastuzumab and bevacizumab) were characterized by quartz crystal microbalance (QCM). Among the four peptide mimotopes initially selected, the peptide designated as CN-14 (CGSGSGSWPRWLEN) was the most selective and sensitive for rituximab binding. The CN-14 SAM was further characterized by ellipsometry and atomic force microscopy. The thickness of the CN-14 SAM film was approximately 32 Å, and the CN-14 SAM is suggested to be stabilized by a salt bridge of Arg-10 and Glu-13 between CN-14 peptides. The CN-14 salt bridge was evaluated by a series of modifications to the CN-14 peptide sequence and characterized by QCM. The CN-14 amide variant produced a better affinity to rituximab than CN-14 without a significant impact on selectivity. As the pKa of the Glu residue of CN-14 increased, the affinity of the SAM to rituximab increased, whereas the selectivity decreased. This was attributed to the weakening of the salt bridge between the CN-14 Arg-10 and Glu-13 at higher pKa values for Glu-13. Our study shows that peptide mimotopes have potential benefits in sensor applications, as the peptide-peptide interactions in the SAMs can be manipulated by the addition of functional groups to the peptide to influence the binding of target proteins. PMID:26609837

  9. Four cases of rituximab-associated melanoma.

    PubMed

    Velter, Charles; Pagès, Cécile; Schneider, Pierre; Osio, Amélie; Brice, Pauline; Lebbé, Céleste

    2014-08-01

    Biological agents have transformed the management of inflammatory and proliferative disorders. Safety issues have been raised, particularly the increased risk of opportunistic infections and secondary cancers. We report four cases of melanoma worsening or occurring after rituximab treatment for associated B-cell lymphoma, and discuss the accountability of the molecule in this process. In three cases, melanoma was diagnosed before or at the same time as a B-cell lymphoma treated with rituximab associated with chemotherapy and we observed rapid metastatic progression. In the last case, melanoma appeared after 5 years treatment with rituximab for a follicular lymphoma. Although it is premature to conclude on the role of rituximab in melanoma, careful follow-up and registration of such cases are important to gain further insight on this topic. PMID:24743053

  10. Rituximab for immune hemolytic anemia following T- and B-Cell-depleted hematopoietic stem cell transplantation.

    PubMed

    Corti, P; Bonanomi, S; Vallinoto, C; Balduzzi, A; Uderzo, C; Cazzaniga, G; Gaipa, G; Dassi, M; Perseghin, P; Rovelli, A

    2003-01-01

    The treatment of immune-mediated hemolytic anemia (IHA) complicating hematopoietic stem cell transplantation (HSCT) is often unsatisfactory. We report a case of IHA which occurred after T- and B-cell depleted unrelated donor HSCT carried out for mucopolysaccharidosis type I-H (Hurler syndrome) which was successfully treated with anti-CD20+ monoclonal antibody PMID:12486323

  11. Rituximab Retreatment for Low-Tumor Burden Follicular Lymphoma

    Cancer.gov

    A summary of results from a randomized clinical trial of patients with low–tumor burden follicular lymphoma that compared maintenance therapy with rituximab versus retreatment with rituximab only when there was evidence of disease progression.

  12. Depletion of B‐Cells With Rituximab Improves Endothelial Function and Reduces Inflammation Among Individuals With Rheumatoid Arthritis

    PubMed Central

    Hsue, Priscilla Y.; Scherzer, Rebecca; Grunfeld, Carl; Imboden, John; Wu, Yuaner; del Puerto, Gus; Nitta, Elaine; Shigenaga, Judy; Schnell Heringer, Amanda; Ganz, Peter; Graf, Jonathan

    2014-01-01

    Background Individuals with rheumatoid arthritis (RA) are at increased risk for cardiovascular disease, partly due to systemic inflammation and endothelial dysfunction. B‐cells play an important pathogenic role in the inflammatory process that drives RA disease activity. Rituximab, a chimeric murine/human monoclonal antibody that depletes B‐cells, is an effective therapy for RA. The purpose of this study was to determine whether B‐cell depletion with rituximab reduces systemic inflammation and improves macrovascular (brachial artery flow‐mediated dilation, FMD) and microvascular (reactive hyperemia) endothelial function in RA patients. Methods and Results RA patients received a single course of rituximab (1000 mg IV infusion at baseline and on day 15). FMD, reactive hyperemia, inflammatory markers, and clinical assessments were performed at baseline, week 12, and week 24. Twenty patients (95% female, median age 54 years) completed the study. Following treatment, FMD improved from a baseline of 4.5±0.4% to 6.4±0.6% at 12 weeks (mean±SE; P<0.0001), followed by a decline at week 24; a similar pattern was observed for hyperemic velocity. Significant decreases in RA disease scores, high‐sensitivity C‐reactive protein, erythrocyte sedimentation rate, and circulating CD19+ B‐cells were sustained through week 24. Cholesterol and triglycerides became significantly although modestly elevated during the study. Conclusions Depletion of B‐cells with rituximab improved macrovascular and microvascular endothelial function and reduced systemic inflammation, despite modest elevation in lipids. Given these results, rituximab should be evaluated in the future for its possible role in reducing excess cardiovascular risk in RA. Clinical Trial Registration URL http://ClinicalTrials.gov. Unique identifier: NCT00844714. PMID:25336464

  13. Idiopathic Nonviral Cryoglobulinemia Treated Successfully With Rituximab.

    PubMed

    Kamel, Mahmoud; Thajudeen, Bijin; Bracamonte, Erika; Madhrira, Machaiah

    2016-01-01

    Cryoglobulinemia is a systemic inflammatory syndrome that generally involves small-to-medium vessel vasculitis due to cryoglobulin-containing immune complexes. The therapeutic management of idiopathic cryoglobulinemic vasculitis has yet to be defined because no study has evaluated the best strategies. However, treatment of severe vasculitis is traditionally based on a combination of corticosteroids and immunosuppressants or plasmapheresis, and more recently rituximab. We report a case of 77-year-old female patient diagnosed with idiopathic cryoglobulinemia, treated successfully with 6 months prednisone tapering and 2 doses of rituximab (1 g each dose). After receiving the above-mentioned treatment, her creatinine went back to normal with resolution of proteinuria and hematuria, normalization of serum complements, and significant improvement in her clinical picture. We conclude that rituximab could be an effective treatment for idiopathic cryoglobulnemia. PMID:24914502

  14. Herpetic tracheitis in association with rituximab therapy.

    PubMed

    Thong, Lorraine; Plant, Barry J; McCarthy, Julie; Murphy, Desmond M

    2016-07-01

    A 58-year old lady under active follow-up with the respiratory services at our institution for bronchiectasis secondary to hypogammaglobulinaemia presented with hoarseness and haemoptysis. She was also receiving rituximab maintenance therapy for follicular lymphoma. Bronchoscopy demonstrated vesicular lesions on her vocal cords and trachea, confirmed as herpes simplex virus (HSV) on cytological analysis of brushings. She responded well to intravenous valacyclovir. Rituximab is increasingly utilised in the treatment of haematological and auto-immune disorders. This case highlights the potential of this drug to potentiate susceptibility to infection in an already immunocompromised individual. PMID:27512561

  15. Chlorambucil-rituximab as first-line therapy in patients affected by follicular non-Hodgkin's lymphoma: a retrospective single-centre study.

    PubMed

    Martinelli, Giovanni; Montoro, Juan; Vanazzi, Anna; Andreola, Giovanna; Liptrott, Sarah; Radice, Davide; Negri, Mara; Preda, Lorenzo; Pruneri, Giancarlo; Laszlo, Daniele

    2015-12-01

    Rituximab, a chimeric monoclonal antibody directed against the CD20 antigen, has been shown to be active in newly diagnosed and relapsed patients with follicular lymphoma (FL), both as monotherapy and in combination with chemotherapy. Many studies suggest that the prognosis of patients with FL may improve when it is used in combination with chemotherapy. Despite these advances, the disease remains essentially incurable with standard therapy, and novel approaches to treatment are needed because optimal therapy is not defined. The combination of chlorambucil-rituximab is one of several standard treatment options for FL. Here, we considered data arising from 75 patients with newly diagnosed FL at the European Institute of Oncology treated with the combination of rituximab plus chlorambucil. The aim of this study was to evaluate the efficacy and safety of chlorambucil and rituximab, delivered 6 mg/m(2) /day orally for 6 weeks and 375 mg/m(2) in a standard 4-weekly schedule, respectively. Patients responding to the induction therapy received a prolonged therapy with four additional cycles of chlorambucil plus rituximab. Seventy-one patients (94.6%) completed the treatment; four patients discontinued treatment because of grade 3-4 hematological toxicity. The overall response rate was 97.3% including 74.7% of complete responses. Only two patients had a stable disease at revaluation after treatment. With a median follow-up of 57 months, 72 patients (96%) are alive. Median event-free survival (EFS) and median overall survival (OS) were not reached; 5-year OS rate was 98.4%. The 5-year EFS was 71.3%. By univariate and multivariate analyses, elevated beta-2 microglobulin levels and partial responses to therapy were correlated with worse EFS. These results suggest that the combination of chlorambucil and rituximab is an active and safe regimen in patients with newly diagnosed FL, principally in those with low tumour burden and favourable prognostic factors. PMID

  16. Cyclophosphamide, fludarabine, alemtuzumab, and rituximab as salvage therapy for heavily pretreated patients with chronic lymphocytic leukemia

    PubMed Central

    Badoux, Xavier C.; Keating, Michael J.; Wang, Xuemei; O'Brien, Susan M.; Ferrajoli, Alessandra; Faderl, Stefan; Burger, Jan; Koller, Charles; Lerner, Susan; Kantarjian, Hagop

    2011-01-01

    Patients with relapsed chronic lymphocytic leukemia (CLL) and high-risk features, such as fludarabine refractoriness, complex karyotype, or abnormalities of chromosome 17p, experience poor outcomes after standard fludaradine-based regimens. Alemtuzumab is a chimeric CD52 monoclonal antibody with activity in CLL patients with fludarabine-refractory disease and 17p deletion. We report the outcome for 80 relapsed or refractory patients with CLL enrolled in a phase 2 study of cyclophosphamide, fludarabine, alemtuzumab, and rituximab (CFAR). All patients were assessed for response and progression according to the 1996 CLL-working group criteria. For the intention-to-treat analysis, the overall response rate was 65%, including 29% complete response. The estimated progression-free survival was 10.6 months and median overall survival was 16.7 months. Although we noted higher complete response in high-risk patients after CFAR compared with a similar population who had received fludarabine, cyclophosphamide, and rituximab as salvage therapy, there was no significant improvement in progression-free survival and overall survival appeared worse. CFAR was associated with a high rate of infectious complications with 37 patients (46%) experiencing a serious infection during therapy and 28% of evaluable patients experiencing late serious infections. Although CFAR produced good response rates in this highly pretreated high-risk group of patients, there was no benefit in survival outcomes. PMID:21670470

  17. Targeted B cell therapies in the treatment of adult and pediatric systemic lupus erythematosus.

    PubMed

    Hui-Yuen, J S; Nguyen, S C; Askanase, A D

    2016-09-01

    Belimumab (Benlysta) is a fully-humanized monoclonal antibody that inhibits B-lymphocyte stimulator (also known as B cell activating factor) and was approved by the U.S. Federal Drug Administration and European Medicines Evaluation Agency for treatment in adults with autoantibody-positive systemic lupus erythematosus (SLE). Rituximab (Rituxan) is a chimeric anti-CD20 monoclonal antibody targeting B lymphocytes. This review discusses the key findings of the phase III trials in adults with SLE and of real-world use of belimumab and rituximab in the care of both adult and pediatric SLE patients. It highlights the safety profile of belimumab and rituximab and gives insight into the consideration of these therapies for specific SLE disease states. It concludes with a discussion of the current clinical trials investigating B cell therapies in specific SLE disease states and a look to the future, with ongoing clinical trials. PMID:27497253

  18. Rapid exacerbation of neuromyelitis optica after rituximab treatment.

    PubMed

    Dai, Yongqiang; Lu, Tingting; Wang, Yuge; Fang, Ling; Li, Rui; Kermode, Allan G; Qiu, Wei

    2016-04-01

    Studies have shown the efficacy of immunosuppressants against neuromyelitis optica (NMO). Rituximab is recommended as an off-label prescription to treat refractory NMO. However, we describe two such patients who were suboptimally responsive to rituximab and whose symptoms worsened after treatment. Our cautionary cases highlight that in a small proportion of patients with refractory NMO, rituximab may either fail or induce rapid relapse of NMO. This suggests we need to consider new treatment strategies for refractory NMO. PMID:26704780

  19. Chimeric enzymes with improved cellulase activities

    SciTech Connect

    Xu, Qi; Baker, John O; Himmel, Michael E

    2015-03-31

    Nucleic acid molecules encoding chimeric cellulase polypeptides that exhibit improved cellulase activities are disclosed herein. The chimeric cellulase polypeptides encoded by these nucleic acids and methods to produce the cellulases are also described, along with methods of using chimeric cellulases for the conversion of cellulose to sugars such as glucose.

  20. Tetravalent anti-CD20/CD3 bispecific antibody for the treatment of B cell lymphoma.

    PubMed

    Lu, Chia-Yen; Chen, Gregory J; Tai, Pei-Han; Yang, Yu-Chen; Hsu, Yu-Shen; Chang, Mingi; Hsu, Chuan-Lung

    2016-05-13

    Bispecific antibodies (bsAbs) are second generation antibodies for therapeutic application in immunotherapy. One of the major strategies of the bsAb platform is the recruitment of immune effector T cells by incorporating an anti-CD3 domain. A bispecific T-cell engager (BiTE), with one end having an affinity for CD3 and the other end with affinity for CD19, has been approved in the US and Europe for the treatment of acute lymphoblastic leukemia. However, due to their small size and lack of Fc region, these single-chain variable fragment (scFv) bsAbs have short half-lives in vivo. Additionally, poor solubility, structural instability, and low production yields have also become major challenges in the bulk production process. To overcome these challenges, we have engineered a tetravalent bsAb with bivalent binding specificity for the CD20 and CD3 antigen in an immunoglobulin G (IgG) format. The fusion of the anti-CD3 scFvs to the CD20 antibody via a linker-hinge domain (LHD) results in improved antibody stabilization and properties. Here we demonstrate this antibody's highly efficient cancer cell elimination in a dose-dependent manner in a CD20-expressing B lymphoblastoid cell line in vitro. Our data suggest the potential clinical application of this bsAb for the treatment of CD20-expressing B cell malignancies. PMID:27040766

  1. Molecular characterization of a variant virus that caused de novo hepatitis B without elevation of hepatitis B surface antigen after chemotherapy with rituximab.

    PubMed

    Miyagawa, Masami; Minami, Masahito; Fujii, Kota; Sendo, Rei; Mori, Kojiro; Shimizu, Daisuke; Nakajima, Tomoaki; Yasui, Kohichiroh; Itoh, Yoshito; Taniwaki, Masafumi; Okanoue, Takeshi; Yoshikawa, Toshikazu

    2008-12-01

    Hepatitis B virus (HBV) reactivation in hepatitis B surface antigen (HBsAg)-negative patients following treatment with rituximab has been reported increasingly. The aim of this study was to investigate the molecular mechanisms underlying HBV reactivation in an HBsAg-negative patient. HBV was reactivated in a 75-year-old man following chemotherapy with rituximab, without elevation of HBsAg. The patient's full-length HBV genome was cloned and the entire sequence was determined. Transfection studies were performed in vitro using recombinant wild-type HBV (wild-type), the patient's HBV (patient), and two chimeric HBV constructs, in which the preS/S region of the patient and wild-type virus had been exchanged with one another. Secreted HBsAg and intra- and extra-cellular HBV DNA were measured. The number of amino acid substitutions in HBV from this patient was much higher than in previous reports of HBV mutants, such as occult HBV and vaccine escape HBV mutants. Levels of HBsAg and HBV DNA production in vitro were significantly lower in the patient compared to wild-type transfections. From analyses of the chimeric constructs, the altered preS/S region was responsible mainly for this impairment. These results show that highly mutated HBV can reactivate after chemotherapy with rituximab, despite an unusually large number of mutations, resulting in impaired viral replication in vitro. Severe immune suppression, probably caused by rituximab, may permit reactivation of highly mutated HBV. These findings have important clinical implications for the prevention and management of HBV reactivation and may explain partially the mechanism of recent, unusual cases of HBV reactivation. PMID:19040281

  2. Rationale and design of the RIACT–study: a multi-center placebo controlled double blind study to test the efficacy of RItuximab in Acute Cellular tubulointerstitial rejection with B-cell infiltrates in renal Transplant patients: study protocol for a randomized controlled trial

    PubMed Central

    2012-01-01

    Background Acute kidney allograft rejection is a major cause for declining graft function and has a negative impact on the long-term graft survival. The majority (90%) of acute rejections are T-cell mediated and, therefore, the anti-rejection therapy targets T-cell-mediated mechanisms of the rejection process. However, there is increasing evidence that intragraft B-cells are also important in the T-cell-mediated rejections. First, a significant proportion of patients with acute T-cell-mediated rejection have B-cells present in the infiltrates. Second, the outcome of these patients is inferior, which has been related to an inferior response to the conventional anti-rejection therapy. Third, treatment of these patients with an anti-CD20 antibody (rituximab) improves the allograft outcome as reported in single case observations and in one small study. Despite the promise of these observations, solid evidence is required before incorporating this treatment option into a general treatment recommendation. Methods/Design The RIACT study is designed as a randomized, double-blind, placebo-controlled, parallel group multicenter Phase III study. The study examines whether rituximab, in addition to the standard treatment with steroid-boli, leads to an improved one-year kidney allograft function, compared to the standard treatment alone in patients with acute T-cell mediated tubulointerstitial rejection and significant B-cell infiltrates in their biopsies. A total of 180 patients will be recruited. Discussion It is important to clarify the relevance of anti-B cell targeting in T-cell mediated rejection and answer the question whether this novel concept should be incorporated in the conventional anti-rejection therapy. Trial registration Clinical trials gov. number: NCT01117662 PMID:23101480

  3. Rituximab Desensitization in Pediatric Patients: Results of a Case Series

    PubMed Central

    Lee, Joyce P.; Platt, Craig D.

    2016-01-01

    Rituximab is a monoclonal antibody (mAb) primarily used to treat oncologic and autoinflammatory conditions. Although hypersensitivity reactions (HSRs) and desensitization protocols to mAbs have been well described in adults, the experience in the pediatric population is very limited. We sought to determine the safety and efficacy of desensitization to rituximab in the pediatric population at our institution. We retrospectively reviewed the experience with HSRs and desensitization to rituximab during a 5-year period in our tertiary care pediatric center, including reaction evaluation, premedication regimens, and desensitization procedures and protocols. A total of 17 desensitizations to rituximab were performed in three patients. A 14-year-old patient underwent successful desensitization to rituximab using a published adult protocol without incident. Two younger patients (ages 7 years and 23 months) experienced significant reactions during initial desensitization attempts. Therefore, we designed a modified desensitization protocol to rituximab, with particular attention to the rate of infusion as mg/kg/h. This new patient weight-based protocol was successfully used in a total of 13 desensitizations in these two patients. Desensitization to rituximab was a safe and effective procedure in our pediatric population. We present a new patient weight-based desensitization protocol for pediatric patients who develop HSRs to rituximab, with particular usefulness for younger pediatric patients and potential utility in pediatric patients with HSRs to other mAbs.

  4. Rituximab in B-Lineage Adult Acute Lymphoblastic Leukemia.

    PubMed

    Maury, Sébastien; Chevret, Sylvie; Thomas, Xavier; Heim, Dominik; Leguay, Thibaut; Huguet, Françoise; Chevallier, Patrice; Hunault, Mathilde; Boissel, Nicolas; Escoffre-Barbe, Martine; Hess, Urs; Vey, Norbert; Pignon, Jean-Michel; Braun, Thorsten; Marolleau, Jean-Pierre; Cahn, Jean-Yves; Chalandon, Yves; Lhéritier, Véronique; Beldjord, Kheira; Béné, Marie C; Ifrah, Norbert; Dombret, Hervé

    2016-09-15

    Background Treatment with rituximab has improved the outcome for patients with non-Hodgkin's lymphoma. Patients with B-lineage acute lymphoblastic leukemia (ALL) may also have the CD20 antigen, which is targeted by rituximab. Although single-group studies suggest that adding rituximab to chemotherapy could improve the outcome in such patients, this hypothesis has not been tested in a randomized trial. Methods We randomly assigned adults (18 to 59 years of age) with CD20-positive, Philadelphia chromosome (Ph)-negative ALL to receive chemotherapy with or without rituximab, with event-free survival as the primary end point. Rituximab was given during all treatment phases, for a total of 16 to 18 infusions. Results From May 2006 through April 2014, a total of 209 patients were enrolled: 105 in the rituximab group and 104 in the control group. After a median follow-up of 30 months, event-free survival was longer in the rituximab group than in the control group (hazard ratio, 0.66; 95% confidence interval [CI], 0.45 to 0.98; P=0.04); the estimated 2-year event-free survival rates were 65% (95% CI, 56 to 75) and 52% (95% CI, 43 to 63), respectively. Treatment with rituximab remained associated with longer event-free survival in a multivariate analysis. The overall incidence rate of severe adverse events did not differ significantly between the two groups, but fewer allergic reactions to asparaginase were observed in the rituximab group. Conclusions Adding rituximab to the ALL chemotherapy protocol improved the outcome for younger adults with CD20-positive, Ph-negative ALL. (Funded by the Regional Clinical Research Office, Paris, and others; ClinicalTrials.gov number, NCT00327678 .). PMID:27626518

  5. Generation of Chimeric Rhesus Monkeys

    PubMed Central

    Tachibana, Masahito; Sparman, Michelle; Ramsey, Cathy; Ma, Hong; Lee, Hyo-Sang; Penedo, Maria Cecilia T.; Mitalipov, Shoukhrat

    2011-01-01

    Summary Totipotent cells in early embryos are progenitors of all stem cells and are capable of developing into a whole organism, including extraembryonic tissues such as placenta. Pluripotent cells in the inner cell mass (ICM) are the descendants of totipotent cells and can differentiate into any cell type of a body except extraembryonic tissues. The ability to contribute to chimeric animals upon reintroduction into host embryos is the key feature of murine totipotent and pluripotent cells. Here, we demonstrate that rhesus monkey embryonic stem cells (ESCs) and isolated ICMs fail to incorporate into host embryos and develop into chimeras. However, chimeric offspring were produced following aggregation of totipotent cells of the 4-cell embryos. These results provide insights into the species-specific nature of primate embryos and suggest that a chimera assay using pluripotent cells may not be feasible. PMID:22225614

  6. Targeted treatment for chronic lymphocytic leukemia: clinical potential of obinutuzumab

    PubMed Central

    Smolej, Lukáš

    2015-01-01

    Introduction of targeted agents revolutionized the treatment of chronic lymphocytic leukemia (CLL) in the past decade. Addition of chimeric monoclonal anti-CD20 antibody rituximab to chemotherapy significantly improved efficacy including overall survival (OS) in untreated fit patients; humanized anti-CD52 antibody alemtuzumab and fully human anti-CD20 antibody ofatumumab lead to improvement in refractory disease. Novel small molecule inhibitors such as ibrutinib and idelalisib demonstrated excellent activity and were very recently licensed in relapsed/refractory CLL. Obinutuzumab (GA101) is the newest monoclonal antibody approved for the treatment of CLL. This novel, glycoengineered, type II humanized anti-CD20 antibody is characterized by enhanced antibody-dependent cellular cytotoxicity and direct induction of cell death compared to type I antibodies. Combination of obinutuzumab and chlorambucil yielded significantly better OS in comparison to chlorambucil monotherapy in untreated comorbid patients. These results led to approval of obinuzutumab for the treatment of CLL. Numerous clinical trials combining obinutuzumab with other cytotoxic drugs and novel small molecules are currently under way. This review focuses on the role of obinutuzumab in the treatment of CLL. PMID:25691812

  7. Rituximab targets podocytes in recurrent focal segmental glomerulosclerosis

    PubMed Central

    Fornoni, Alessia; Sageshima, Junichiro; Wei, Changli; Merscher-Gomez, Sandra; Robier, Aguillon-Prada; Jauregui, Alexandra N.; Li, Jing; Mattiazzi, Adela; Ciancio, Gaetano; Chen, Linda; Zilleruelo, Gaston; Abitbol, Carolyn; Chandar, Jayanthi; Seeherunvong, Wacheree; Ricordi, Camillo; Ikehata, Masami; Rastaldi, Maria Pia; Reiser, Jochen; Burke, George W.

    2013-01-01

    Focal segmental glomerulosclerosis (FSGS) is a prevalent glomerular disease characterized by proteinuria, progression to end stage renal disease and recurrence of proteinuria after kidney transplantation in approximately one third of patients. It has been suggested that rituximab might treat recurrent FSGS through an unknown mechanism. Rituximab recognizes CD20 on B-lymphocytes but might also bind sphingomyelin-phosphodiesterase-acid-like-3b (SMPDL-3b) and regulates acid-sphyngomyelinase (ASMase) activity. We hypothesized that rituximab prevents recurrent FSGS and preserves podocyte SMPDL-3b expression. We studied 41 patients at high risk for recurrent FSGS, 27 of whom were treated with rituximab at time of kidney transplant. Incidence of nephrotic-range proteinuria and change in estimated glomerular filtration rate (ΔeGFR) were analyzed. SMPDL-3b immunostaining was performed in post-reperfusion kidney biopsies. SMPDL-3b protein, ASMase activity, and cytoskeleton remodeling were studied in cultured normal human podocytes that had been exposed to patient sera with or without rituximab. Rituximab treatment was associated with lower incidence of post-transplant proteinuria and decreased ΔeGFR. The number of SMPDL-3b+ podocytes in post-reperfusion biopsies was reduced in patients who developed recurrent FSGS. Rituximab partially prevented SMPDL-3b and ASMase downregulation that was observed in podocytes treated with the sera of patients with recurrent FSGS. Either SMPDL-3b overexpression or treatment with rituximab prevented disruption of the actin cytoskeleton and podocyte apoptosis induced by patient sera. This effect was diminished in cultured podocytes where the gene encoding SMPDL-3b was silenced. Our study suggests that treatment of high-risk patients with rituximab at time of kidney transplant might prevent recurrent FSGS by modulating podocyte function in an SMPDL-3b–dependent manner. PMID:21632984

  8. Rituximab targets podocytes in recurrent focal segmental glomerulosclerosis.

    PubMed

    Fornoni, Alessia; Sageshima, Junichiro; Wei, Changli; Merscher-Gomez, Sandra; Aguillon-Prada, Robier; Jauregui, Alexandra N; Li, Jing; Mattiazzi, Adela; Ciancio, Gaetano; Chen, Linda; Zilleruelo, Gaston; Abitbol, Carolyn; Chandar, Jayanthi; Seeherunvong, Wacheree; Ricordi, Camillo; Ikehata, Masami; Rastaldi, Maria Pia; Reiser, Jochen; Burke, George W

    2011-06-01

    Focal segmental glomerulosclerosis (FSGS) is a glomerular disease characterized by proteinuria, progression to end-stage renal disease, and recurrence of proteinuria after kidney transplantation in about one-third of patients. It has been suggested that rituximab might treat recurrent FSGS through an unknown mechanism. Rituximab not only recognizes CD20 on B lymphocytes, but might also bind sphingomyelin phosphodiesterase acid-like 3b (SMPDL-3b) protein and regulate acid sphingomyelinase (ASMase) activity. We hypothesized that rituximab prevents recurrent FSGS and preserves podocyte SMPDL-3b expression. We studied 41 patients at high risk for recurrent FSGS, 27 of whom were treated with rituximab at time of kidney transplant. SMPDL-3b protein, ASMase activity, and cytoskeleton remodeling were studied in cultured normal human podocytes that had been exposed to patient sera with or without rituximab. Rituximab treatment was associated with lower incidence of posttransplant proteinuria and stabilization of glomerular filtration rate. The number of SMPDL-3b(+) podocytes in postreperfusion biopsies was reduced in patients who developed recurrent FSGS. Rituximab partially prevented SMPDL-3b and ASMase down-regulation that was observed in podocytes treated with the sera of patients with recurrent FSGS. Overexpression of SMPDL-3b or treatment with rituximab was able to prevent disruption of the actin cytoskeleton and podocyte apoptosis induced by patient sera. This effect was diminished in cultured podocytes where SMPDL-3b was silenced. Our study suggests that treatment of high-risk patients with rituximab at time of kidney transplant might prevent recurrent FSGS by modulating podocyte function in an SMPDL-3b-dependent manner. PMID:21632984

  9. Cost-effectiveness of rituximab in refractory cold agglutinin disease.

    PubMed

    Panwar, U; Mathews, C; Cullis, J O

    2008-08-01

    Cold haemagglutinin disease (CHAD) is an uncommon condition frequently associated with B-cell lymphoproliferative disorders and is refractory to conventional treatments used in autoimmune haemolytic anaemia. Rituximab has been used in this condition with favourable and lasting responses. Cost has been a major limitation to its use in such indication. We present cost-effectiveness analysis of the use of rituximab in two patients with CHAD. Rituximab successfully controlled haemolysis in both cases of CHAD and was found to be cost-effective through reducing transfusion needs. PMID:18665831

  10. Rituximab monitoring and redosing in pediatric neuromyelitis optica spectrum disorder

    PubMed Central

    Nosadini, Margherita; Alper, Gulay; Riney, Catherine J.; Benson, Leslie A.; Mohammad, Shekeeb S.; Ramanathan, Sudarshini; Nolan, Melinda; Appleton, Richard; Leventer, Richard J.; Deiva, Kumaran; Brilot, Fabienne; Gorman, Mark P.; Waldman, Amy T.; Banwell, Brenda

    2016-01-01

    Objective: To study rituximab in pediatric neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSD) and the relationship between rituximab, B cell repopulation, and relapses in order to improve rituximab monitoring and redosing. Methods: Multicenter retrospective study of 16 children with NMO/NMOSD receiving ≥2 rituximab courses. According to CD19 counts, events during rituximab were categorized as “repopulation,” “depletion,” or “depletion failure” relapses (repopulation threshold CD19 ≥10 × 106 cells/L). Results: The 16 patients (14 girls; mean age 9.6 years, range 1.8–15.3) had a mean of 6.1 events (range 1–11) during a mean follow-up of 6.1 years (range 1.6–13.6) and received a total of 76 rituximab courses (mean 4.7, range 2–9) in 42.6-year cohort treatment. Before rituximab, 62.5% had received azathioprine, mycophenolate mofetil, or cyclophosphamide. Mean time from rituximab to last documented B cell depletion and first repopulation was 4.5 and 6.8 months, respectively, with large interpatient variability. Earliest repopulations occurred with the lowest doses. Significant reduction between pre- and post-rituximab annualized relapse rate (ARR) was observed (p = 0.003). During rituximab, 6 patients were relapse-free, although 21 relapses occurred in 10 patients, including 13 “repopulation,” 3 “depletion,” and 4 “depletion failure” relapses. Of the 13 “repopulation” relapses, 4 had CD19 10–50 × 106 cells/L, 10 had inadequate monitoring (≤1 CD19 in the 4 months before relapses), and 5 had delayed redosing after repopulation detection. Conclusion: Rituximab is effective in relapse prevention, but B cell repopulation creates a risk of relapse. Redosing before B cell repopulation could reduce the relapse risk further. Classification of evidence: This study provides Class IV evidence that rituximab significantly reduces ARR in pediatric NMO/NMOSD. This study also demonstrates a relationship between B cell repopulation

  11. Prolonged Remission in Neuromyelitis Optica Following Cessation of Rituximab Treatment.

    PubMed

    Weinfurtner, Kelley; Graves, Jennifer; Ness, Jayne; Krupp, Lauren; Milazzo, Maria; Waubant, Emmanuelle

    2015-09-01

    Neuromyelitis optica is an autoimmune disease characterized by acute episodes of transverse myelitis and optic neuritis. Several small, open-label studies suggest rituximab, a monoclonal antibody against CD20, prevents relapses in neuromyelitis optica; however, there is little consensus on timing or duration of treatment. Here we report four patients with severe relapsing neuromyelitis optica who were stabilized on rituximab and, after discontinuing treatment, continued to experience prolonged remission of their disease. Remission ranged from 4.5 to 10.5 years total, including 3 to 9 years off all therapies. The patients had sustained clinical responses despite normal B-lymphocyte levels and, in at least 2 patients, continued seropositivity for aquaporin-4 antibodies. These cases suggest that rituximab may induce prolonged remission in certain neuromyelitis optica patients, and they highlight the need for further elucidation of rituximab's mechanism in neuromyelitis optica. PMID:25387545

  12. Screening for viral hepatitis prior to rituximab chemotherapy.

    PubMed

    Leonard, A N; Love, B L; Norris, L B; Siddiqui, S K; Wallam, M N; Bennett, C L

    2016-01-01

    In 2008, the CDC published guidelines recommending screening of all persons undergoing treatment with rituximab to identify persons at risk of hepatitis B virus (HBV) reactivation. We evaluated implementation of this recommendation in veterans, who are at increased risk of HBV, and determined characteristics of those screened. We also evaluated a control setting, rates of hepatitis C virus (HCV) screening among the same rituximab-treated patients. There are no guidelines that recommend HCV screening prior to initiation of rituximab. Medical records of patients receiving rituximab between January 2006 and December 2012 were reviewed according to two time periods: 2006-2008 (period 1, pre-guidelines) and 2009-2012 (period 2, post-guidelines). Patient demographics, concomitant chemotherapy regimen (protocol, dose, duration), treatment indication, risk factors for hepatitis infection (substance abuse, homelessness, human immunodeficiency virus (HIV)), and HBV/HCV screening status were documented. During the study period, 102 patients were treated with rituximab (49 in period 1 and 53 in period 2). During periods 1 and 2, 22 and 32 % of rituximab-treated patients were screened for HBV, respectively (p = 0.375). Treatment during 2009 was the only significant predictor of HBV screening in the adjusted model (p = 0.01). For HCV during periods 1 and 2, 22 and 21 % of patients were screened, respectively (p = 1.00). There were no significant predictors of HCV screening. Rates of screening for HBV among rituximab-treated patients were low, both before and after dissemination of guidelines recommending universal HBV screening of rituximab-treated patients. PMID:26382277

  13. Rituximab therapy in nephrotic syndrome due to AH amyloidosis.

    PubMed

    Katoh, Nagaaki; Matsuda, Masayuki; Miyazaki, Daigo; Gono, Takahisa; Yazaki, Masahide; Ikeda, Shu-Ichi

    2009-01-01

    We report a patient with AH amyloidosis associated with lymphoplasmacytic leukemia that has remained in a stable state with a nephrotic syndrome for 17 months since the commencement of cyclic rituximab therapy aimed at suppression of pathogenetic gamma heavy chains. Free light chains in serum and CD20-positive cells in peripheral blood were useful as hematological markers in the patient. Rituximab might be a potent therapeutic option for AH amyloidosis associated with a B-cell lymphoproliferative disorder. PMID:19590993

  14. Validated LC/MS Bioanalysis of Rituximab CDR Peptides Using Nano-surface and Molecular-Orientation Limited (nSMOL) Proteolysis.

    PubMed

    Iwamoto, Noriko; Takanashi, Megumi; Hamada, Akinobu; Shimada, Takashi

    2016-07-01

    Presently, monoclonal antibodies (mAbs) therapeutics have big global sales and are starting to receive competition from biosimilars. We previously reported that the nano-surface and molecular-orientation limited (nSMOL) proteolysis which is optimal method for bioanalysis of antibody drugs in plasma. The nSMOL is a Fab-selective limited proteolysis, which utilize the difference of protease nanoparticle diameter (200 nm) and antibody resin pore diameter (100 nm). In this report, we have demonstrated that the full validation for chimeric antibody Rituximab bioanalysis in human plasma using nSMOL proteolysis. The immunoglobulin fraction was collected using Protein A resin from plasma, which was then followed by the nSMOL proteolysis using the FG nanoparticle-immobilized trypsin under a nondenaturing condition at 50°C for 6 h. After removal of resin and nanoparticles, Rituximab signature peptides (GLEWIGAIYPGNGDTSYNQK, ASGYTFTSYNMHWVK, and FSGSGSGTSYSLTISR) including complementarity-determining region (CDR) and internal standard P14R were simultaneously quantified by multiple reaction monitoring (MRM). This quantification of Rituximab using nSMOL proteolysis showed lower limit of quantification (LLOQ) of 0.586 µg/mL and linearity of 0.586 to 300 µg/mL. The intra- and inter-assay precision of LLOQ, low quality control (LQC), middle quality control (MQC), and high quality control (HQC) was 5.45-12.9% and 11.8, 5.77-8.84% and 9.22, 2.58-6.39 and 6.48%, and 2.69-7.29 and 4.77%, respectively. These results indicate that nSMOL can be applied to clinical pharmacokinetics study of Rituximab, based on the precise analysis. PMID:27150271

  15. Idelalisib and Rituximab in Relapsed Chronic Lymphocytic Leukemia

    PubMed Central

    Cheson, Bruce D.; Pagel, John M.; Hillmen, Peter; Barrientos, Jacqueline C.; Zelenetz, Andrew D.; Kipps, Thomas J.; Flinn, Ian; Ghia, Paolo; Eradat, Herbert; Ervin, Thomas; Lamanna, Nicole; Coiffier, Bertrand; Pettitt, Andrew R.; Ma, Shuo; Stilgenbauer, Stephan; Cramer, Paula; Aiello, Maria; Johnson, Dave M.; Miller, Langdon L.; Li, Daniel; Jahn, Thomas M.; Dansey, Roger D.; Hallek, Michael; O’Brien, Susan M.

    2014-01-01

    BACKGROUND Patients with relapsed chronic lymphocytic leukemia (CLL) who have clinically significant coexisting medical conditions are less able to undergo standard chemo-therapy. Effective therapies with acceptable side-effect profiles are needed for this patient population. METHODS In this multicenter, randomized, double-blind, placebo-controlled, phase 3 study, we assessed the efficacy and safety of idelalisib, an oral inhibitor of the delta iso-form of phosphatidylinositol 3-kinase, in combination with rituximab versus rituximab plus placebo. We randomly assigned 220 patients with decreased renal function, previous therapy-induced myelosuppression, or major coexisting illnesses to receive rituximab and either idelalisib (at a dose of 150 mg) or placebo twice daily. The primary end point was progression-free survival. At the first prespecified interim analysis, the study was stopped early on the recommendation of the data and safety monitoring board owing to overwhelming efficacy. RESULTS The median progression-free survival was 5.5 months in the placebo group and was not reached in the idelalisib group (hazard ratio for progression or death in the idelalisib group, 0.15; P<0.001). Patients receiving idelalisib versus those receiving placebo had improved rates of overall response (81% vs. 13%; odds ratio, 29.92; P<0.001) and overall survival at 12 months (92% vs. 80%; hazard ratio for death, 0.28; P = 0.02). Serious adverse events occurred in 40% of the patients receiving idelalisib and rituximab and in 35% of those receiving placebo and rituximab. CONCLUSIONS The combination of idelalisib and rituximab, as compared with placebo and rituximab, significantly improved progression-free survival, response rate, and overall survival among patients with relapsed CLL who were less able to undergo chemo-therapy. (Funded by Gilead; ClinicalTrials.gov number, NCT01539512.) PMID:24450857

  16. Rituximab versus Cyclophosphamide for ANCA-Associated Vasculitis

    PubMed Central

    Stone, John H.; Merkel, Peter A.; Spiera, Robert; Seo, Philip; Langford, Carol A.; Hoffman, Gary S.; Kallenberg, Cees G.M.; St. Clair, E. William; Turkiewicz, Anthony; Tchao, Nadia K.; Webber, Lisa; Ding, Linna; Sejismundo, Lourdes P.; Mieras, Kathleen; Weitzenkamp, David; Ikle, David; Seyfert-Margolis, Vicki; Mueller, Mark; Brunetta, Paul; Allen, Nancy B.; Fervenza, Fernando C.; Geetha, Duvuru; Keogh, Karina A.; Kissin, Eugene Y.; Monach, Paul A.; Peikert, Tobias; Stegeman, Coen; Ytterberg, Steven R.; Specks, Ulrich

    2011-01-01

    BACKGROUND Cyclophosphamide and glucocorticoids have been the cornerstone of remission-induction therapy for severe antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis for 40 years. Uncontrolled studies suggest that rituximab is effective and may be safer than a cyclophosphamide-based regimen. METHODS We conducted a multicenter, randomized, double-blind, double-dummy, noninferiority trial of rituximab (375 mg per square meter of body-surface area per week for 4 weeks) as compared with cyclophosphamide (2 mg per kilogram of body weight per day) for remission induction. Glucocorticoids were tapered off; the primary end point was remission of disease without the use of prednisone at 6 months. RESULTS Nine centers enrolled 197 ANCA-positive patients with either Wegener’s granulomatosis or microscopic polyangiitis. Baseline disease activity, organ involvement, and the proportion of patients with relapsing disease were similar in the two treatment groups. Sixty-three patients in the rituximab group (64%) reached the primary end point, as compared with 52 patients in the control group (53%), a result that met the criterion for noninferiority (P<0.001). The rituximab-based regimen was more efficacious than the cyclophosphamide-based regimen for inducing remission of relapsing disease; 34 of 51 patients in the rituximab group (67%) as compared with 21 of 50 patients in the control group (42%) reached the primary end point (P = 0.01). Rituximab was also as effective as cyclophosphamide in the treatment of patients with major renal disease or alveolar hemorrhage. There were no significant differences between the treatment groups with respect to rates of adverse events. CONCLUSIONS Rituximab therapy was not inferior to daily cyclophosphamide treatment for induction of remission in severe ANCA-associated vasculitis and may be superior in relapsing disease. (Funded by the National Institutes of Allergy and Infectious Diseases, Genentech, and Biogen; Clinical

  17. Is rituximab sub-optimally dosed in indolent B cell lymphoma?

    PubMed

    Sawalha, Yazeed; Rouphail, Basel; Jia, Xuefei; Dean, Robert M; Hill, Brian T; Jagadeesh, Deepa; Pohlman, Brad L; Smith, Mitchell R

    2016-09-01

    Rituximab pharmacokinetics are affected by gender, age and weight and can affect outcomes in aggressive B cell lymphoma. Less is known about the pharmacokinetics of rituximab in indolent B cell lymphoma (iNHL). We analysed the effects of gender, age, weight and body surface area on the outcomes of 303 patients treated with first line rituximab-based regimens for iNHL. The patients were divided into 3 treatment cohorts: rituximab only, rituximab + chemotherapy (R-CTX) and R-CTX followed by rituximab maintenance; furthermore, each cohort was subdivided as follicular (FL) or non-FL, based on histology. Older males and patients with higher weight had worse outcomes when treated with R-CTX, probably due to faster rituximab clearance. Our results concur with studies of R-CTX for DLBCL. As this effect was not observed in patients treated with rituximab alone or R-CTX followed by rituximab maintenance, we hypothesize that higher rituximab levels reached with weekly rituximab and/or prolonged exposure achieved with maintenance therapy exceed the therapeutic threshold, even with faster clearance, which nullifies the negative effect of higher weight and male gender. In conclusion, under current practices, a subset of patients with iNHL, i.e., FL treated with R-CTX, may be sub-optimally dosed with rituximab. PMID:27136331

  18. Rituximab and biosimilars – equivalence and reciprocity

    PubMed Central

    Qureshi, Zaina P; Magwood, Jametta S; Singh, Sarveshwari; Bennett, Charles L

    2014-01-01

    Cancer is a debilitating disease affecting millions of people daily. Over the years, cancer treatment has advanced in leaps and bounds. Antibodies are important breakthrough therapeutic agents for cancer. These agents, proteins produced by B lymphocytes of the immune system in response to antigens, bind to receptors on cell surfaces so that the antigen–antibody complexes can be recognized and destroyed by phagocytes. While each B cell synthesizes only one kind of antibody, an entire population of different types of B cells and their respective antibodies are produced in response to various antigens to which the organism had been exposed. However, to be useful clinically, substantial amounts of a single antibody must be generated from a single ancestral B cell. These antibodies produced by a specific population of B cells are the monoclonal antibodies that have become the cornerstone of treatment for cancer and many immunologic illnesses. The purpose of this report is to provide an overview of the clinical development of biosimilars in clinical oncology, focusing on rituximab and like biosimilars. PMID:24829884

  19. Rituximab in combination with multiagent chemotherapy for pediatric follicular lymphoma.

    PubMed

    Kumar, Riten; Galardy, Paul J; Dogan, Ahmet; Rodriguez, Vilmarie; Khan, Shakila P

    2011-08-01

    Given the rarity of follicular lymphoma (FL) in children, there is limited data on which to base treatment recommendations. Herein, we report our institutional experience of using rituximab with multiagent chemotherapy for pediatric FL. Six pediatric patients were diagnosed with FL from 2000 to 2009. All patients received rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for varying durations. Five of the six patients remain in remission with a median follow-up of 31 months. Larger randomized trials are indicated to establish the efficacy of this regimen for pediatric FL patients. PMID:21462303

  20. Blood chimerism in a dizygotic dichorionic pregnancy.

    PubMed

    Jang, Ja-Hyun; Jung, Haiyoung; Kim, Jong-Hwa; Park, Won-Soon; Kim, Sun-Hee

    2010-10-01

    Blood chimerism in twins is known to occur through the transfer of hematopoietic stem cells between the fetuses via a common placenta. We present a case of blood chimerism in a dizygotic dichorionic twin pregnancy. The female twin was delivered at 34 weeks of gestation, and the male twin was stillborn. Pathologic examination confirmed dichorionic diamniotic placentas. The karyotype of the female child was obtained using peripheral blood sample, and it revealed a mixture of 46,XX and 46,XY cells (chi 46,XY[13]/46,XX[7]). FISH analysis performed on the buccal cells by using CEP X/Y probe (Abbott Molecular Inc., USA) revealed 100% XX signals (nuc ish Xcen(DXZ1x2)[500]). Gross examination of the external genitalia and abdominal ultrasonography revealed no definitive abnormal findings in relation to sex differentiation. When XX/XY chimerism is present in blood lymphocytes, careful examination of external genitalia and reproductive organs and further studies are required to detect chimerism in non-hematopoetic tissues. This is a rare case of blood chimerism in dichorionic placentas, in contrast to those in monochorionic placentas. PMID:20890086

  1. Rituximab therapy for primary glomerulonephritis: Report on two cases

    PubMed Central

    Fabrizi, Fabrizio; Cresseri, Donata; Fogazzi, Giovanni B; Moroni, Gabriella; Passerini, Patrizia; Martin, Paul; Messa, Piergiorgio

    2015-01-01

    The evidence in the medical literature on the efficacy and safety of rituximab therapy for primary glomerulonephritis is limited and controversial. We describe two male Caucasian patients with rapidly progressive kidney failure due to primary proliferative glomerulonephritis. Both of them received high-dose intravenous corticosteroids and oral cyclophosphamide with limited benefit. The first patient (hepatitis C virus-negative mixed cryoglobulinemia) underwent plasma-exchange with intravenous immunoglobulins; he showed significant benefit on kidney function (he became dialysis independent with serum creatinine going back to 1.6 mg/dL) after one rituximab pulse even if urinary abnormalities were still present. No improvement in renal function or urinary changes occurred in the second patient. Both these individuals developed sepsis over the follow-up, the first patient died two months after rituximab therapy. This report is in keeping with the occurrence of severe infections after rituximab therapy in patients with renal impairment at baseline and concomitant high-dose steroids. PMID:26301235

  2. Rituximab-associated acute thrombocytopenia: an under-diagnosed phenomenon.

    PubMed

    Ram, Ron; Bonstein, Lilach; Gafter-Gvili, Anat; Ben-Bassat, Isaac; Shpilberg, Ofer; Raanani, Pia

    2009-04-01

    Acute infusion reactions are the most common documented adverse reactions reported with rituximab, with overt cytokine release syndrome, and hematological adverse events being much rarer. The clinical course of a patient with mantle cell lymphoma, who developed acute thrombocytopenia and leukopenia following rituximab administration, is described and the literature reviewed. Serum complement and the levels of three cytokines--TNF-alpha, IL-6, and IL-1, were measured 2 days after the infusion of rituximab by using ELISA assay. Drug-dependent antibodies against platelets were evaluated by two procedures as follows: an immunofluorescence test applying flow cytometry and Monoclonal Antibody Immobilization of Platelet Antigen (MAIPA). Serum levels of TNF-a were significantly increased compared with normal, whereas those of IL-6 and IL-1 were not increased significantly. Flow cytometry assay and the MAIPA assay failed to detect rituximab-dependent antibodies against platelets. Complement levels were decreased compared with normal. Literature search yielded 10 publications reporting on another 15 patients. The most common type of lymphoma was mantle cell lymphoma, six patients had bone marrow involvement, and 10 patients had splenomegaly. In 10 patients, acute cytopenia was preceded by cytokine release syndrome or infusion-related symptoms. Usually, thrombocytopenia was not associated with bleeding manifestations. Thrombocytopenia was the most commonly acute cytopenia reported. The postulated pathogenesis is associated with cytokine release syndrome and complement activation. Patients with potential risk factors like splenomegaly and bone marrow involvement, who develop clinical manifestations compatible with cytokine release syndrome, should be closely monitored for rituximab-associated cytopenia. PMID:19260124

  3. Time Savings with Rituximab Subcutaneous Injection versus Rituximab Intravenous Infusion: A Time and Motion Study in Eight Countries

    PubMed Central

    De Cock, Erwin; Kritikou, Persefoni; Sandoval, Mariana; Tao, Sunning; Wiesner, Christof; Carella, Angelo Michele; Ngoh, Charles; Waterboer, Tim

    2016-01-01

    Background Rituximab is a standard treatment for non-Hodgkin lymphoma. The SABRINA trial (NCT01200758) showed that a subcutaneous (SC) rituximab formulation did not compromise efficacy or safety compared with intravenous (IV) infusion. We aimed to quantify active healthcare professional (HCP) time and patient chair time for rituximab SC and IV, including potential time savings. Methods This non-interventional time and motion study was run in eight countries and 30 day oncology units. Rituximab SC data were collected alongside the MabCute trial (NCT01461928); IV data were collected per routine real-world practice. Trained observers recorded active HCP time for pre-specified tasks (stopwatch) and chair time (time of day). A random intercept model was used to analyze active HCP time (by task and for all tasks combined) in the treatment room and drug preparation area, drug administration duration, chair time and patient treatment room time by country and/or across countries. Active HCP and chair time were extrapolated to a patient’s first year of treatment (11 rituximab sessions). Results Mean active HCP time was 35.0 and 23.7 minutes for IV and SC process, respectively (-32%, p <0.0001). By country, relative reduction in time was 27–58%. Absolute reduction in extrapolated active HCP time (first year of treatment) was 1.1–5.2 hours. Mean chair time was 262.1 minutes for IV, including 180.9 minutes infusion duration, vs. 67.3 minutes for SC, including 8.3 minutes SC injection administration (-74%, p <0.0001). By country, relative reduction was 53–91%. Absolute reduction in extrapolated chair time for the first year of treatment was 3.1–5.5 eight-hour days. Conclusions Compared with rituximab IV, rituximab SC was associated with reduced chair time and active HCP time. The latter could be invested in other activities, whereas the former may lead to more available appointments, reducing waiting lists and increasing the efficiency of day oncology units. Trial

  4. The role of Gr1+ cells after anti-CD20 treatment in type 1 diabetes in NOD mice

    PubMed Central

    Hu, Changyun; Du, Wei; Zhang, Xiaojun; Wong, F. Susan; Wen, Li

    2015-01-01

    Studies suggest that Gr1+CD11b+ cells have immunoregulatory function and these cells may play an important role in autoimmune diseases. In this study, we investigated the regulatory role of Gr1+CD11b+ cells in protecting against type 1 diabetes in NOD mice. Here we showed that temporary B cell depletion induced the expansion of Gr1+CD11b+ cells. Gr1+CD11b+ cells not only directly suppress diabetogenic T cell function, but can also induce Treg differentiation in a TGF-β-dependent manner. Furthermore, we found that Gr1+CD11b+ cells could suppress diabetogenic CD4 and CD8 T cell function in an IL-10-, nitric oxide- and cell contact- dependent manner. Interestingly, single anti-Gr1 monoclonal antibody treatment can also induce a transient expansion of Gr1+CD11b+ cells that delayed diabetes development in NOD mice. Our data suggest that Gr1+CD11b+ cells contribute to the establishment of immune tolerance to pancreatic islet autoimmunity. Manipulation of Gr1+CD11b+ cells could be considered as a novel immunotherapy for the prevention of type 1 diabetes. PMID:22140261

  5. Comparative Efficacy of 177Lu and 90Y for Anti-CD20 Pretargeted Radioimmunotherapy in Murine Lymphoma Xenograft Models

    SciTech Connect

    Frost, Sophia; Frayo, Shani; Miller, Brian W.; Orozco, Johnnie J.; Booth, Garrett C.; Hylarides, Mark; Lin, Yukang; Green, Damian J.; Gopal, Ajay K.; Pagel, John M.; Back, Tom; Fisher, Darrell R.; Press, Oliver W.

    2015-03-01

    Pretargeted radioimmunotherapy (PRIT) is a multi-step method of selectively delivering high doses of radiotherapy to tumor cells while minimizing exposure to surrounding tissues. Yttrium-90 (90Y) and lutetium-177 (177Lu) are two of the most promising beta-particle emitting radionuclides used for radioimmunotherapy, which despite having similar chemistries differ distinctly in terms of radiophysical features. These differences may have important consequences for the absorbed dose to tumors and normal organs. Whereas 90Y has been successfully applied in a number of preclinical and clinical radioimmunotherapy settings, there have been few published pretargeting studies with 177Lu. We therefore compared the therapeutic potential of targeting either 90Y or 177Lu to human B-cell lymphoma xenografts in mice.

  6. Novel antisense therapeutics delivery systems: In vitro and in vivo studies of liposomes targeted with anti-CD20 antibody.

    PubMed

    Meissner, Justyna M; Toporkiewicz, Monika; Czogalla, Aleksander; Matusewicz, Lucyna; Kuliczkowski, Kazimierz; Sikorski, Aleksander F

    2015-12-28

    Antisense gene therapy using molecules such as antisense oligodeoxynucleotides, siRNA or miRNA is a very promising strategy for the treatment of neoplastic diseases. It can be combined with other treatment strategies to enhance therapeutic effect. In acute leukemias, overexpression of the antiapoptotic gene BCL2 is observed in more than 70% of cases. Therefore, reduction of the Bcl-2 protein level could, in itself, prevent the development of cancer or could possibly help sensitize cancer cells to apoptosis inducers. The main objective of our work is to develop therapeutic liposome formulations characterized by high transfection efficiency, stability in the presence of serum, as well as specificity and toxicity for target (leukemic) cells. Each of our liposomal formulations consists of a core composed of antisense oligonucleotides complexed by either cationic lipid, DOTAP, or a synthetic polycation, polyethyleneimine, encapsulated within liposomes modified with polyethylenoglycol. In addition, the liposomal shells are enriched with covalently-bound antibodies recognizing a well characterized bio-marker, CD20, exposed on the surface of leukemia cells. The resulting immunoliposomes selectively and effectively reduced the expression of BCL2 in target cells. Model animal experiments carried out on mice-engrafted tumors expressing the specific marker showed high efficiency of the liposome formulations against specific tumor development. In conclusion, we show that lipid formulations based on a polyplex or lipoplex backbone additionally equipped with antibodies are promising non-viral vectors for specific oligonucleotide transfer into human tumor cells. PMID:26585505

  7. Rituximab add-on therapy for breakthrough relapsing multiple sclerosis

    PubMed Central

    Naismith, R.T.; Piccio, L.; Lyons, J.A.; Lauber, J.; Tutlam, N.T.; Parks, B.J.; Trinkaus, K.; Song, S.K.; Cross, A.H.

    2010-01-01

    Objective: B cells and the humoral immune system have been implicated in the pathogenesis of multiple sclerosis (MS). This study sought to evaluate the efficacy, safety, and tolerability of add-on therapy with rituximab, a monoclonal antibody that depletes circulating B cells, in subjects with relapsing MS with breakthrough disease defined by clinical and MRI activity (Class III evidence). Methods: Thirty subjects with a relapse within the past 18 months despite use of an injectable disease-modifying agent, and with at least 1 gadolinium-enhancing (GdE) lesion on any of 3 pretreatment MRIs, received rituximab administered at 375 mg/m2 weekly × 4 doses. Three monthly posttreatment brain MRI scans were obtained beginning 12 weeks after the first infusion. Multiple Sclerosis Functional Composite (MSFC) and Expanded Disability Status Scale (EDSS) were obtained at baseline and throughout the posttreatment follow-up. Results: GdE lesions were reduced after treatment with rituximab, with 74% of posttreatment MRI scans being free of GdE activity compared with 26% free of GdE activity at baseline (p < 0.0001). Median GdE lesions were reduced from 1.0 to 0, and mean number was reduced from 2.81 per month to 0.33 after treatment (88% reduction). MSFC improved as well (p = 0.02). EDSS remained stable. Conclusion: Rituximab add-on therapy was effective based upon blinded radiologic endpoints in this phase II study. In combination with standard injectable therapies, rituximab was well-tolerated with no serious adverse events. B-cell–modulating therapy remains a potential option for treatment of patients with relapsing MS with an inadequate response to standard injectable therapies. Classification of evidence: This study provides Class III evidence that add-on rituximab reduces gadolinium-enhancing brain lesions in multiple sclerosis. GLOSSARY DMT = disease-modifying therapy; EDSS = Expanded Disability Status Scale; FOV = field of view; GdE = gadolinium-enhancing; HACA = human

  8. Rituximab efficiently depletes B cells in lung tumors and normal lung tissue

    PubMed Central

    Joly-Battaglini, Albane; Hammarström, Clara; Stankovic, Branislava; Aamodt, Henrik; Stjärne, Johan; Brustugun, Odd Terje; Helland, Åslaug; Øynebråten, Inger; Corthay, Alexandre

    2016-01-01

    Rituximab is a monoclonal antibody that targets the CD20 B-cell-specific antigen and is widely used as therapy for B-cell lymphoma. Since rituximab depletes both malignant and normal B cells, it is increasingly being used to treat various conditions in which normal B cells have a pathogenic role, such as rheumatoid arthritis and multiple sclerosis. It is well-established that rituximab efficiently eliminates B cells in blood, lymph nodes, and spleen. In contrast, the effect of rituximab in non-lymphoid tissues remains poorly documented and is debated. Here, we report a rheumatoid arthritis patient who was treated with rituximab before receiving thoracic surgery for non-small cell lung cancer. Using flow cytometry and immunohistochemistry, we show that rituximab efficiently depleted CD20-positive B cells in a primary lung tumor, in lung-associated lymph nodes, and in normal lung tissue. We conclude that rituximab may be very efficient at depleting normal B cells in the lungs. This property of rituximab may potentially be exploited for the treatment of conditions in which pathogenic B cells reside in the lungs. On the other hand, the clearance of lung B cells may provide an explanation for the rare cases of severe non-infectious pulmonary toxicity of rituximab. PMID:27081474

  9. Protein biochip array technology to monitor rituximab in rheumatoid arthritis

    PubMed Central

    Fabre, S; Guisset, C; Tatem, L; Dossat, N; Dupuy, A M; Cohen, J D; Cristol, J P; Daures, J P; Jorgensen, C

    2009-01-01

    In rheumatoid arthritis (RA) there are currently no good indicators to predict a clinical response to rituximab. The purpose of this study was to monitor and determine the role of peripheral blood cytokine profiling in differentiating between a good versus poor response to rituximab in RA. Blood samples were collected at baseline and at 3 months from 46 RA patients who were treated with rituximab. Responders are defined by the presence of three of four American College of Rheumatology criteria: ≥ 20% decrease in C-reactive protein, visual analogical score of disease activity, erythrocyte sedimentation rate and improvement of the disease activity score (28) (four values) by ≥ 1·2 obtained at 3 months. Twelve cytokines were measured from serum collected on days 0 and 90 by proteomic array, including interleukin-6 (IL-6), tumour necrosis factor-α, IL-1a, IL-1b, IL-2, IL-8, interferon-γ, IL-4, IL-10, monocyte chemoattractant protein-1, epidermal growth factor and vascular growth factor. We showed that C-reactive protein and IL-6 levels decrease significantly at 3 months in the responder group compared with baseline. At day 90 we identified a cytokine profile which differentiates responders and non-responders. High serum levels of two proinflammatory cytokines, monocyte chemoattractant protein-1 and epidermal growth factor, were significantly higher in the responder group at day 90 compared with non-responders. However, we were not able to identify a baseline cytokine profile predictive of a good response at 3 months. These findings suggest that cytokine profiling by proteomic analysis may be a promising tool for monitoring rituximab and may help in the future to identify responder RA patients. PMID:19220830

  10. Rituximab-Induced Splenic Rupture and Cytokine Release

    PubMed Central

    Nair, Ranjit; Gheith, Shereen; Lamparella, Nicholas

    2016-01-01

    Patient: Female, 55 Final Diagnosis: Mantle cell lymphoma Symptoms: Cytokine release syndrome • hypoglycemia • hypotension • splenic rupture • splenomegaly • vision loss Medication: — Clinical Procedure: Case Report Specialty: Oncology Objective: Unusual clinical course Background: Rituximab is a therapeutic monoclonal antibody that is used for many different lymphomas. Post-marketing surveillance has revealed that the risk of fatal reaction with rituximab use is extremely low. Splenic rupture and cytokine release syndrome are rare fatal adverse events related to the use of therapeutic monoclonal antibodies, especially in aggressive malignancies with high tumor burden. Case Report: A 55-year-old woman presented with abdominal pain and type B symptoms and was diagnosed with mantle cell lymphoma. Initial peripheral blood flow cytometry showed findings that mimicked features of chronic lymphocytic leukemia. Further treatment with rituximab led to catastrophic treatment complications that proved to be fatal for the patient. Conclusions: Severe cytokine release syndrome associated with biologics carries a very high morbidity and case fatality rate. With this case report we aim to present the diagnostic challenge with small B-cell neoplasms, especially mantle cell lymphoma and chronic lymphocytic lymphomas, and underscore the importance of thorough risk assessment for reactions prior to treatment initiation. PMID:26972227

  11. Engineering of chimeric class II polyhydroxyalkanoate synthases.

    PubMed

    Niamsiri, Nuttawee; Delamarre, Soazig C; Kim, Young-Rok; Batt, Carl A

    2004-11-01

    PHA synthase is a key enzyme involved in the biosynthesis of polyhydroxyalkanoates (PHAs). Using a combinatorial genetic strategy to create unique chimeric class II PHA synthases, we have obtained a number of novel chimeras which display improved catalytic properties. To engineer the chimeric PHA synthases, we constructed a synthetic phaC gene from Pseudomonas oleovorans (phaC1Po) that was devoid of an internal 540-bp fragment. Randomly amplified PCR products (created with primers based on conserved phaC sequences flanking the deleted internal fragment) were generated using genomic DNA isolated from soil and were substituted for the 540-bp internal region. The chimeric genes were expressed in a PHA-negative strain of Ralstonia eutropha, PHB(-)4 (DSM 541). Out of 1,478 recombinant clones screened for PHA production, we obtained five different chimeric phaC1Po genes that produced more PHA than the native phaC1Po. Chimeras S1-71, S4-8, S5-58, S3-69, and S3-44 exhibited 1.3-, 1.4-, 2.0-, 2.1-, and 3.0-fold-increased levels of in vivo activity, respectively. All of the mutants mediated the synthesis of PHAs with a slightly increased molar fraction of 3-hydroxyoctanoate; however, the weight-average molecular weights (Mw) of the PHAs in all cases remained almost the same. Based upon DNA sequence analyses, the various phaC fragments appear to have originated from Pseudomonas fluorescens and Pseudomonas aureofaciens. The amino acid sequence analyses showed that the chimeric proteins had 17 to 20 amino acid differences from the wild-type phaC1Po, and these differences were clustered in the same positions in the five chimeric clones. A threading model of PhaC1Po, developed based on homology of the enzyme to the Burkholderia glumae lipase, suggested that the amino acid substitutions found in the active chimeras were located mostly on the protein model surface. Thus, our combinatorial genetic engineering strategy proved to be broadly useful for improving the catalytic

  12. The risk of infections in hematologic patients treated with rituximab is not influenced by cumulative rituximab dosage - a single center experience

    PubMed Central

    2014-01-01

    Background Rituximab, a monoclonal antibody directed against CD20, is approved for the treatment of CD20-positive B-cell Non-Hodgkin’s lymphoma and rheumatologic disorders. Due to its potent activity in depleting CD20-positive lymphocytes, the influence on opportunistic infections is still under discussion. Thus, we analyzed the impact of rituximab either as monotherapy or in combination with other chemotherapeutic regimens to elucidate its role in contributing to infectious complications. Methods The records of consecutive patients (n = 125, 141 treatment episodes) treated with rituximab alone or in combination with chemotherapy and corticosteroids were analyzed retrospectively for the incidence, spectrum and outcome of infections during treatment and 6 months after the last course of rituximab. Univariate analysis of cofactors such as steroid medication, antiinfective prophylaxis, underlying disease and remission status were performed. Results Altogether 80 therapy episodes were associated with infections, the median number of infections per patient being 1 (range 1–7). The number of infectious complications was significantly higher in patients receiving a combination of rituximab and chemotherapy compared to rituximab monotherapy (p < 0.001). There was no statistically significant difference regarding number of rituximab courses or cumulative rituximab dosage between episodes with and without infections, respectively.Mean cumulative prednisone dosage between the cohort with infections and the one without infections showed a trend towards higher dosage of prednisone in the patients with infections (mean difference 441 mg, p > 0.14). Conclusions Rituximab in induction treatment, either as monotherapy or combined with chemotherapy by itself does not increase the incidence or change the spectrum of infections in hematologic patients. However the possible influence of higher dosages of concomitant steroid medication on frequency of infections

  13. Development of chimeric laccases by directed evolution.

    PubMed

    Pardo, Isabel; Vicente, Ana Isabel; Mate, Diana M; Alcalde, Miguel; Camarero, Susana

    2012-12-01

    DNA recombination methods are useful tools to generate diversity in directed evolution protein engineering studies. We have designed an array of chimeric laccases with high-redox potential by in vitro and in vivo DNA recombination of two fungal laccases (from Pycnoporus cinnabarinus and PM1 basidiomycete), which were previously tailored by laboratory evolution for functional expression in Saccharomyces cerevisiae. The laccase fusion genes (including the evolved α-factor prepro-leaders for secretion in yeast) were subjected to a round of family shuffling to construct chimeric libraries and the best laccase hybrids were identified in dual high-throughput screening (HTS) assays. Using this approach, we identified chimeras with up to six crossover events in the whole sequence, and we obtained active hybrid laccases with combined characteristics in terms of pH activity and thermostability. PMID:22729887

  14. Adverse Events of Monoclonal Antibodies Used for Cancer Therapy

    PubMed Central

    Guan, Mei; Zhou, Yan-Ping; Sun, Jin-Lu; Chen, Shu-Chang

    2015-01-01

    In 1997, the first monoclonal antibody (MoAb), the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug administration for use in cancer patients. Since then, the panel of MoAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has continued to expand, currently encompassing a stunning amount of 20 distinct molecules for 11 targets. We provide a brief scientific background on the use of MoAbs in cancer therapy, review all types of monoclonal antibodies-related adverse events (e.g., allergy, immune-related adverse events, cardiovascular adverse events, and pulmonary adverse events), and discuss the mechanism and treatment of adverse events. PMID:26075239

  15. Adverse events of monoclonal antibodies used for cancer therapy.

    PubMed

    Guan, Mei; Zhou, Yan-Ping; Sun, Jin-Lu; Chen, Shu-Chang

    2015-01-01

    In 1997, the first monoclonal antibody (MoAb), the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug administration for use in cancer patients. Since then, the panel of MoAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has continued to expand, currently encompassing a stunning amount of 20 distinct molecules for 11 targets. We provide a brief scientific background on the use of MoAbs in cancer therapy, review all types of monoclonal antibodies-related adverse events (e.g., allergy, immune-related adverse events, cardiovascular adverse events, and pulmonary adverse events), and discuss the mechanism and treatment of adverse events. PMID:26075239

  16. Immunotherapeutic approaches for the treatment of childhood, adolescent and young adult non-Hodgkin lymphoma.

    PubMed

    Barth, Matthew J; Chu, Yaya; Hanley, Patrick J; Cairo, Mitchell S

    2016-05-01

    With the introduction of the anti-CD20 monoclonal antibody rituximab, B-cell non-Hodgkin lymphoma was the first malignancy successfully treated with an immunotherapeutic agent. Since then, numerous advances have expanded the repertoire of immunotherapeutic agents available for the treatment of a variety of malignancies, including many lymphoma subtypes. These include the introduction of monoclonal antibodies targeting a variety of cell surface proteins, including the successful targeting of immunoregulatory checkpoint receptors present on T-cells or tumour cells. Additionally, cellular immunotherapeutic approaches utilize T- or Natural Killer-cells generated with chimeric antigen receptors against cell surface proteins or Epstein-Barr virus-associated latent membrane proteins. The following review describes the current state of immunotherapy for non-Hodgkin lymphoma including a summary of currently available data and promising agents currently in clinical development with future promise in the treatment of childhood, adolescent and young adult non-Hodgkin lymphoma. PMID:27062282

  17. Targeted therapies for CLL: Practical issues with the changing treatment paradigm.

    PubMed

    Jain, Nitin; O'Brien, Susan

    2016-05-01

    Chemoimmunotherapy (CIT) such as FCR (fludarabine, cyclophosphamide, rituximab) has been the standard first-line therapy for younger patients with CLL. In the last few years, several novel targeted therapies have been developed for patients with CLL. These include B-cell receptor (BCR) inhibitors such as Bruton tyrosine kinase (BTK) inhibitors, PI3 kinase inhibitors, and Syk inhibitors, novel anti-CD20 monoclonal antibodies such as ofatumumab and obinutuzumab, and Bcl-2 antagonists such as venetoclax (ABT-199). Strategies targeting the immune system such as lenalidomide, chimeric antigen receptor (CAR) T cells, and more recently, checkpoint inhibitors, are in clinical development. Ibrutinib and idelalisib are already approved for patients with relapsed and refractory CLL. Ibrutinib is also approved for first-line treatment of CLL patients with del(17p). Several ongoing phase III clinical trials with novel therapies will further define the role of targeted agents in CLL. PMID:26776345

  18. Effectiveness of Rituximab in Severe Wegener’s Granulomatosis: Report of Two Cases and Review of the Literature

    PubMed Central

    Oristrell, Joaquim; Bejarano, Guillermina; Jordana, Rosa; Monteagudo, Manuel; Marí, Begoña; Casanovas, Arnau; Tolosa, Carles

    2009-01-01

    We hereby describe the satisfactory evolution of rituximab treatment in two patients with Wegener’s granulomatosis (WG). Rituximab was indicated for refractoriness to standard treatment in one case and life-threatening myelotoxicity due to alkylating agents in the other. A brief review of previous experience with the use of rituximab in the treatment of WG is presented. PMID:19590594

  19. The potential role for ocrelizumab in the treatment of multiple sclerosis: current evidence and future prospects

    PubMed Central

    Sorensen, Per Soelberg; Blinkenberg, Morten

    2016-01-01

    B cells play a central role in the pathogenesis in multiple sclerosis (MS), being involved in the activation of proinflammatory T cells, secretion of proinflammatory cytokines, and production of autoantibodies directed against myelin. Hence, the usage of B-cell-depleting monoclonal antibodies as therapy for autoimmune diseases including MS lay near at hand. Rituximab was the first therapeutic B-cell-depleting chimeric monoclonal antibody to be used successfully in MS. Ocrelizumab, a second-generation humanized anti-CD20 antibody, was explored in a large phase II, randomized, placebo-controlled multicentre trial in patients with relapsing–remitting disease. Compared with placebo, two doses of ocrelizumab (600 and 2000 mg on days 1 and 15) showed a pronounced effect on disease activity seen in magnetic resonance imaging (MRI) as gadolinium-enhanced lesions (89% and 96% relative reduction, both p < 0.001) and also had a significant effect on relapses. In exploratory analyses, both doses of ocrelizumab had better effect on gadolinium-enhanced lesions than interferon beta-1a intramuscularly that was used as a reference arm. Adverse effects were mainly infusion-related reactions, in particular during the first infusion. Serious infections occurred at similar rates in ocrelizumab and placebo-treated patients, and no opportunistic infections were reported. However, progressive multifocal leukoencephalopathy (PML) has been reported in patients treated with anti-CD20 monoclonal antibodies for other indications. Other anti-CD20 monoclonal antibodies have been tested as treatments for MS, including ofatumumab that has shown beneficial results in placebo-controlled phase II trials in patients with relapsing–remitting MS. Ocrelizumab is now in phase III development for the treatment of relapsing–remitting MS, as well as primary progressive MS, and the results of ongoing clinical trials are eagerly awaited and will determine the place of ocrelizumab in the armamentarium of

  20. A hybrid protein-polymer nanoworm potentiates apoptosis better than a monoclonal antibody.

    PubMed

    Aluri, Suhaas Rayudu; Shi, Pu; Gustafson, Joshua A; Wang, Wan; Lin, Yi-An; Cui, Honggang; Liu, Shuanglong; Conti, Peter S; Li, Zibo; Hu, Peisheng; Epstein, Alan L; MacKay, John Andrew

    2014-03-25

    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 nanostructures. To explore this strategy, this manuscript introduces a nanoparticle that assembles from a fusion between a single chain antibody and a soluble protein polymer. These hybrid proteins express in Escherichia coli and do not require bioconjugation between the antibody and a substrate. Surprisingly a fusion between an anti-CD20 single chain antibody and a soluble protein polymer assemble worm-like nanostructures, which were characterized using light scattering and cryogenic transmission electron microscopy. These nanoworms competitively bind CD20 on two B-cell lymphoma cell lines, exhibit concentration-dependent induction of apoptosis, and induce apoptosis better than Rituximab alone. Similar activity was observed in vivo using a non-Hodgkin lymphoma xenograft model. In comparison to Rituximab, systemic nanoworms significantly slowed tumor growth. These findings suggest that hybrid nanoworms targeted at CD20 may be useful treatments for B-cell related malignancies. Because of the ubiquity of antibody therapeutics, related nanoworms may have uses against other molecular targets. PMID:24484356

  1. The Effect of Rituximab on Vaccine Responses in Patients with Immune Thrombocytopenia

    PubMed Central

    Nazi, Ishac; Kelton, John G.; Larché, Mark; Snider, Denis P.; Heddle, Nancy M.; Crowther, Mark A.; Cook, Richard J.; Tinmouth, Alan T.; Mangel, Joy; Arnold, Donald M.

    2013-01-01

    B-cell depletion therapy may impair vaccine responses and increase infection risk in patients with immune thrombocytopenia (ITP). Capitalizing on a multicenter randomized placebo-controlled trial, we investigated the effects of rituximab on the antibody and cellular responses to Streptococcus pneumoniae polysaccharide vaccine and Haemophilus influenzae type b (Hib) conjugate vaccine in ITP patients. Of 60 patients in the main trial, 24 patients received both vaccines 6 months after rituximab (n=17) or placebo (n=7). Among 20 evaluable patients, 3/14 (21%) in the rituximab group and 4/6 (67%) in the placebo group achieved a 4-fold increase in anti-pneumococcal antibodies (p=0.12). For anti-Hib antibodies, 4/14 (29%) and 5/6 (83%), respectively, achieved a 4-fold increase (p<0.05). Fewer patients in the rituximab group demonstrated functional Hib killing (2/14 [14%] versus 5/6 [83%], p<0.05). Three of 14 rituximab-treated patients failed to respond to vaccines by any criteria. After vaccinations, pre-plasma cell blasts and interferon-γ secreting T-cells were reduced in rituximab-treated patients. We found that antibody responses were impaired for at least 6 months after rituximab. Cellular immunity was reduced in parallel with the depleted B-cell pool. These findings have implications for the timing of vaccinations and the mechanism of infection after rituximab in patients with ITP. PMID:23851398

  2. Rituximab in the treatment of shrinking lung syndrome in systemic lupus erythematosus.

    PubMed

    Peñacoba Toribio, Patricia; Córica Albani, María Emilia; Mayos Pérez, Mercedes; Rodríguez de la Serna, Arturo

    2014-01-01

    Shrinking lung syndrome (SLS) is a rare manifestation of systemic lupus erythematosus. We report the case of a patient with non-responding SLS (neither to glucocorticoids nor immunosupresors), who showed remarkable improvement after the onset of treatment with rituximab. Although there is a little evidence, treatment with rituximab could be proposed in SLS when classical treatment fails. PMID:24315464

  3. Efficiency of treatment with rituximab in platelet transfusion refractoriness: a study of 7 cases

    PubMed Central

    Liu, Wenbin; Wu, Dijiong; Hu, Tonglin; Ye, Baodong

    2015-01-01

    Objective: The purpose of our study was to evaluate the efficacy and safety of rituximab in treatment of immune PR. Methods: We retrospective analysis 7 paitents (5 aplastic anemia, 2 myelodysplastic syndrome) with immune PR who received at least 3 weekly infusions of rituximab (375 mg/m2). Results: All enrolled patients acquired improvement of platelets transfusion more than 2 months (CCI ≥ 4.5 × 109/L). We first found that there were 2 patterns of response to rituximab treatment in patients with immune PR, which the early but transient after the first rituximab administration and the late but continuous beginning to appear at 3 weeks from the start of treatment. Conclusion: Rituximab is a promising treatment in patients with immune PR and giving the opportunity and time for cure the disease. PMID:26550372

  4. Detection and quantification of chimerism by droplet digital PCR.

    PubMed

    George, David; Czech, Juliann; John, Bobby; Yu, Min; Jennings, Lawrence J

    2013-01-01

    Accurate quantification of chimerism and microchimerism is proving to be increasingly valuable for hematopoietic cell transplantation as well as non-transplant conditions. However, methods that are available to quantify low-level chimerism lack accuracy. Therefore, we developed and validated a method for quantifying chimerism based on digital PCR technology. We demonstrate accurate quantification that far exceeds what is possible with analog qPCR down to 0.01% with the potential to go even lower. Also, this method is inherently more informative than qPCR. We expect the advantages of digital PCR will make it the preferred method for chimerism analysis. PMID:23974275

  5. Mixed chimerism to induce tolerance: lessons learned from nonhuman primates

    PubMed Central

    Murakami, Toru; Cosimi, A. Benedict; Kawai, Tatsuo

    2013-01-01

    The mixed chimerism approach has been demonstrated to be an effective means of inducing allograft tolerance. Based on our rodent studies on mixed chimerism, we previously developed a clinically relevant nonmyeloablative preparative regimen that permits the induction of mixed chimerism and renal allograft tolerance following donor bone marrow transplantation in major histocompatibility complex fully mismatched cynomolgus monkeys. This approach has been successfully extended to HLA matched or mismatched kidney transplant recipients. In the manuscript, we summarize some of the important conclusions made in our laboratories regarding induction of mixed chimerism and allograft tolerance in a nonhuman primate model. PMID:19027614

  6. Construction and Evaluation of a Maize Chimeric Promoter with Activity in Kernel Endosperm and Embryo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chimeric promoters contain DNA sequences from different promoters. Chimeric promoters are developed to increase the level of recombinant protein expression, precisely control transgene activity, or to escape homology-based gene silencing. Sets of chimeric promoters, each containing different lengt...

  7. Rituximab for troublesome cases of childhood nephrotic syndrome

    PubMed Central

    Safdar, Osama Y; Aboualhameael, Adila; Kari, Jameela A

    2014-01-01

    Nephrotic syndrome (NS) is the most common glomerular disease of childhood. Steroid-dependent and steroid-resistant nephrotic syndrome present challenges in their pharmaceutical management; patients may need several immunosuppressive medication for optimum control, each of which medication has its own safety profile. Rituximab (RTX) is a monoclonal antibody that targets B cells and has been used successfully for management of lymphoma and rheumatoid arthritis. Recent clinical studies showed that rituximab may be an efficacious and safe alternative for the treatment of complicated nephrotic syndrome. In this review article, we aim to review the efficacy and safety of RTX therapy in nephrotic syndrome. We reviewed the literature pertaining to this topic by searching for relevant studies on PubMed and Medline using specific keywords. The initial search yielded 452 articles. These articles were then examined to ensure their relevance to the topic of research. We focused on multicenter randomized controlled trials with relatively large numbers of patients. A total of 29 articles were finally identified and will be summarized in this review. The majority of clinical studies of RTX in complicated pediatric NS showed that rituximab is effective in approximately 80% of patients with steroid-dependent NS, as it decreases the number of relapses and steroid dosage. However, RTX is less effective at achieving remission in steroid-resistant NS. RTX use was generally safe, and most side effects were transient and infusion-related. More randomized, double-blinded clinical studies are needed to assess the role of RTX in children with nephrotic syndrome. PMID:25512892

  8. Rituximab's new therapeutic target: the podocyte actin cytoskeleton.

    PubMed

    Chan, Andrew C

    2011-06-01

    Therapeutic off-target activities are well recognized for small-molecule drugs. In contrast, monoclonal antibodies (mAbs) traditionally are believed to act specifically and lack off-target therapeutic effects. In this issue of Science Translational Medicine, Fornoni et al. show therapeutic benefit, through an off-target-mediated mechanism, of the mAb drug rituximab in recurrent focal segmental glomerulosclerosis (FSGS) after kidney transplantation. These data shed new light on FSGS pathogenesis and suggest new therapeutic interventions for proteinuric diseases. PMID:21632983

  9. Treatment of Rheumatoid Arthritis with Biologic DMARDS (Rituximab and Etanercept)

    PubMed Central

    Gashi, Afrim A.; Rexhepi, Sylejman; Berisha, Idriz; Kryeziu, Avni; Ismaili, Jehona; Krasniqi, Gezim

    2014-01-01

    ABSTRACT Goal: To determine efficacy and safety of treatment with Rituximab and Etanercept plus Methotrexate in patients with active Rheumatoid Arthritis (RA), who had an inadequate response to nonbiologic DMARDS therapies and to explore the pharmacogenetics and pharmacodynamics of Rituximab and Etanercept in our populations. Study was done at Rheumatology Clinic of University Clinical Centre in Prishtina during 2009-2011 years. Methods: We evaluated primary efficacy and safety at 24 weeks in patients enrolled in the study of long term efficacy of Rituximab and Etanercept. Patients with active Rheumatoid Arthritis and an inadequate response to 1 or more non biologic DMARDS were randomized to receive intravenous Rituximab (1 course consisting of 2 infusions of 1.000 mg each –one group, and Etanercept 25 mg twice weekly –second group, but both groups with background MTX. The primary efficacy end point was a response on the ACR 20%, improvement criteria at 24 weeks, Secondary end points were responses on the ACR 50 and ACR 70, improvement criteria, the DAS 28, and EULAR response criteria at 24 weeks. Results: During our investigations we treated 20 patients, 15 females and 5 males, in the treated group with RTX and 13 patients 8 females and 5 males in the treated group with ETN. Patients of group 1 and group 2 were of ages 37-69 years old and 19-69 years old (average 47-44) Most of the patients belong in 2nd and 3 rd functional stage according to Steinbrocker. All ACR response parameters were significantly improved in RTX treated patients who also had clinically meaningful improvement in fatigue, disability and quality of life. Patients showed a trend less progression in radiographic end points. Most adverse events occurred with the first RTX infusion and were mild to moderate severity. Conclusion: At 24 weeks, a single course of RTX and ETN provided significant and clinically meaningful improvements in disease activity in patients with active, longstanding RA who

  10. Chimeric Lyssavirus Glycoproteins with Increased Immunological Potential

    PubMed Central

    Jallet, Corinne; Jacob, Yves; Bahloul, Chokri; Drings, Astrid; Desmezieres, Emmanuel; Tordo, Noël; Perrin, Pierre

    1999-01-01

    The rabies virus glycoprotein molecule (G) can be divided into two parts separated by a flexible hinge: the NH2 half (site II part) containing antigenic site II up to the linear region (amino acids [aa] 253 to 275 encompassing epitope VI [aa 264]) and the COOH half (site III part) containing antigenic site III and the transmembrane and cytoplasmic domains. The structural and immunological roles of each part were investigated by cell transfection and mouse DNA-based immunization with homogeneous and chimeric G genes formed by fusion of the site II part of one genotype (GT) with the site III part of the same or another GT. Various site II-site III combinations between G genes of PV (Pasteur virus strain) rabies (GT1), Mokola (GT3), and EBL1 (European bat lyssavirus 1 [GT5]) viruses were tested. Plasmids pGPV-PV, pGMok-Mok, pGMok-PV, and pGEBL1-PV induced transient expression of correctly transported and folded antigens in neuroblastoma cells and virus-neutralizing antibodies against parental viruses in mice, whereas, pG-PVIII (site III part only) and pGPV-Mok did not. The site III part of PV (GT1) was a strong inducer of T helper cells and was very effective at presenting the site II part of various GTs. Both parts are required for correct folding and transport of chimeric G proteins which have a strong potential value for immunological studies and development of multivalent vaccines. Chimeric plasmid pGEBL1-PV broadens the spectrum of protection against European lyssavirus genotypes (GT1, GT5, and GT6). PMID:9847325

  11. Dissociation between peripheral blood chimerism and tolerance to hindlimb composite tissue transplants: preferential localization of chimerism in donor bone

    PubMed Central

    Rahhal, Dina N.; Xu, Hong; Huang, Wei-Chao; Wu, Shengli; Wen, Yujie; Huang, Yiming; Ildstad, Suzanne T.

    2009-01-01

    Background Mixed chimerism induces donor-specific tolerance to composite tissue allotransplants (CTA). In the present studies, we used a nonmyeloablative conditioning approach to establish chimerism and promote CTA acceptance. Methods WF (RT1Au) rats were conditioned with 600-300 cGy total body irradiation (TBI, day-1), 100 × 106 T cell-depleted ACI (RT1Aabl) bone marrow cells were transplanted day 0, followed by a 11-day course of tacrolimus and one dose of anti-lymphocyte serum (day 10). Heterotopic osteomyocutaneous flap transplantation was performed 4-6 weeks after bone marrow transplantation. Results Mixed chimerism was initially achieved in almost all recipients, but long-term acceptance of CTA was only achieved in rats treated with 600 cGy TBI. When anti-αβ-TCR mAb (day-3) was added into the regimens, donor chimerism was similar to recipients preconditioned without anti-αβ-TCR mAb. However, the long-term CTA survival was significantly improved in chimeras receiving ≥ 300 cGy TBI plus anti-αβ-TCR mAb. Higher levels of donor chimerism were associated with CTA acceptance. The majority of flap-acceptors lost peripheral blood (PB) chimerism within 6 months. However, donor chimerism persisted in transplanted bone at significantly higher levels compared to other hematopoietic compartments. The compartment donor chimerism may be responsible for the maintenance of tolerance to CTA. Long-term acceptors were tolerant to a donor skin graft challenge even in the absence of PB chimerism. Conclusions Mixed chimerism established by nonmyeloablative conditioning induces long-term acceptance of CTA which is associated with persistent chimerism preferentially in transplanted donor bone. PMID:19920776

  12. Rituximab for treatment of inhibitors in haemophilia A. A Phase II study.

    PubMed

    Leissinger, C; Josephson, C D; Granger, S; Konkle, B A; Kruse-Jarres, R; Ragni, M V; Journeycake, J M; Valentino, L; Key, N S; Gill, J C; McCrae, K R; Neufeld, E J; Manno, C; Raffini, L; Saxena, K; Torres, M; Marder, V; Bennett, C M; Assmann, S F

    2014-09-01

    The development of antibodies against infused factor VIII (FVIII) in patients with haemophilia A is a serious complication leading to poorly controlled bleeding and increased morbidity. No treatment has been proven to reduce high titre antibodies in patients who fail immune tolerance induction or are not candidates for it. The Rituximab for the Treatment of Inhibitors in Congenital Hemophilia A (RICH) study was a phase II trial to assess whether rituximab can reduce anamnestic FVIII antibody (inhibitor) titres. Male subjects with severe congenital haemophilia A and an inhibitor titre ≥5 Bethesda Units/ml (BU) following a FVIII challenge infusion received rituximab 375 mg/m² weekly for weeks 1 through 4. Post-rituximab inhibitor titres were measured monthly from week 6 through week 22 to assess treatment response. Of 16 subjects who received at least one dose of rituximab, three (18.8%) met the criteria for a major response, defined as a fall in inhibitor titre to <5 BU, persisting after FVIII re-challenge. One subject had a minor response, defined as a fall in inhibitor titre to <5 BU, increasing to 5-10 BU after FVIII re-challenge, but <50% of the original peak inhibitor titre. Rituximab is useful in lowering inhibitor levels in patients, but its effect as a solo treatment strategy is modest. Future studies are indicated to determine the role of rituximab as an adjunctive therapy in immune tolerisation strategies. PMID:24919980

  13. A systematic review of the use of rituximab as induction therapy in renal transplantation.

    PubMed

    Macklin, Philip S; Morris, Peter J; Knight, Simon R

    2015-04-01

    Rituximab is a B-lymphocyte depleting agent used to treat lymphoma and autoimmune diseases. There has been recent interest in its use both for management of highly-sensitised and ABO-incompatible recipients but also for induction therapy before transplantation. This systematic review evaluates the evidence for its use as part of induction protocols in ABO-compatible, non-sensitised recipients. 4 databases and 3 trial registries were searched for studies of the use of rituximab as part of induction protocols. The small number of identified studies precluded meta-analysis and thus a narrative review was conducted. 12 manuscripts met the inclusion criteria, relating to 5 individual studies. No significant improvements in patient and graft survival or acute rejection rates were identified with rituximab induction. A single small study reported a trend towards improved graft function with the addition of rituximab induction to a standard immunosuppressive regimen. Rituximab was not found to be associated with increased infectious complications in any study but concerns were raised over possible associations with leukopaenia and cardiovascular mortality. Overall, no convincing benefit of rituximab induction was found and some safety concerns were identified. The results of on-going trials are awaited but further studies may be required before we can draw firm conclusions regarding the efficacy and safety of rituximab in this setting. PMID:25555541

  14. In vivo B-cell depletion with rituximab for alternative donor hemopoietic SCT.

    PubMed

    Dominietto, A; Tedone, E; Soracco, M; Bruno, B; Raiola, A M; Van Lint, M T; Geroldi, S; Lamparelli, T; Galano, B; Gualandi, F; Frassoni, F; Bacigalupo, A

    2012-01-01

    We retrospectively analyzed 55 patients given a fixed dose of rituximab (200 mg) on day+5 after an alternative donor transplant, to prevent EBV DNA-emia; 68 alternative transplants who did not receive prophylactic rituximab served as controls. The two groups were comparable for donor type, and all patients received anti-thymocyte globulin in the conditioning regimen. Rituximab patients had a significantly lower rate of EBV DNA-emia 56 vs 85% (P=0.0004), a lower number of maximum median EBV copies (91 vs 1321/10(5) cells, P=0.003) and a significantly lower risk of exceeding 1000 EBV copies per 10(5)cells (14 vs 49%, P=0.0001). Leukocyte and lymphocyte counts were lower on day +50 and+100 in rituximab patients, whereas Ig levels were comparable. The cumulative incidence of grade II-IV acute GvHD was significantly reduced in rituximab patients (20 vs 38%, P=0.02). Chronic GvHD was comparable. There was a trend for a survival advantage for patients receiving rituximab (46 vs 40%, P=0.1), mainly because of lower transplant mortality (25 vs 37%, P=0.1). Despite the drawback of a retrospective study, these data suggest that a fixed dose of rituximab on day +5 reduces the risk of a high EBV load, and also reduces acute GvHD. PMID:21460867

  15. Rituximab in the treatment of autoimmune haemolytic anaemia.

    PubMed

    Rodrigo, Chaturaka; Rajapakse, Senaka; Gooneratne, Lallindra

    2015-05-01

    Rituximab is a B-cell depleting monoclonal antibody that is gaining popularity as an effective therapy for many autoimmune cytopenias. This article systematically evaluates its therapeutic efficacy in the treatment of different types of autoimmune haemolytic anaemia. We conclude that there is sufficient evidence to recommend it as a second line therapy for warm autoimmune haemolytic anaemia (wAIHA) either as monotherapy or combined therapy. Evidence from a single randomized controlled trial suggests that it may also be more efficacious as first line therapy in combination with steroids than steroids alone. A fewer number of studies have assessed its role in cold autoimmune haemolytic anaemia (cAIHA) and cold agglutinin disease (CAD) with success rates varying from 45-66%. In the absence of alternative definitive therapy, rituximab should be considered for patients with symptomatic CAD and significant haemolysis. Case reports of its efficacy in mixed autoimmune haemolytic anaemias are available but evidence from case series or larger cohorts are nonexistent. PMID:25139610

  16. Common variable immunodeficiency, immune thrombocytopenia, rituximab and splenectomy: important considerations.

    PubMed

    Arays, Ruta; Goyal, Sahil; Jordan, Kim M

    2016-08-01

    Common variable immunodeficiency (CVID) is readily considered in patients presenting with recurrent sino-pulmonary infections, however this disease has a broad range of clinical manifestations and diagnosis can be delayed by several years. We present the case of a 44-year-old postpartum female who presented with nausea, vomiting and abdominal distension. Four years prior, she was hospitalized for treatment of immune thrombocytopenia (ITP) with splenectomy and rituximab followed by two episodes of bacterial meningitis despite immunizations. The recurrent meningitis had been attributed to splenectomy and immunotherapy. During this hospitalization, extensive workup for gastrointestinal pathology was negative and she was diagnosed with intestinal pseudo-obstruction. Her hospital course was complicated by development of severe pseudomonas pneumonia, and subsequent immunoglobulin testing and impaired antibody response to vaccines were consistent with CVID. We review the clinical presentation of CVID, its association with autoimmune disease, and treatment implications, specifically the impact of rituximab therapy and splenectomy on immunoglobulin function and risk of serious infection. Intestinal pseudo-obstruction has been reported in children with CVID, but literature search failed to reveal similar presentation in adults. Physicians must consider the heterogeneous clinical manifestations of CVID to avoid delay in diagnosis and treatment. Institution of appropriate therapy with immunoglobulin replacement is important to decrease risk of serious infection. PMID:27276370

  17. Salvage Regimens With Autologous Transplantation for Relapsed Large B-Cell Lymphoma in the Rituximab Era

    PubMed Central

    Gisselbrecht, Christian; Glass, Bertram; Mounier, Nicolas; Singh Gill, Devinder; Linch, David C.; Trneny, Marek; Bosly, Andre; Ketterer, Nicolas; Shpilberg, Ofer; Hagberg, Hans; Ma, David; Brière, Josette; Moskowitz, Craig H.; Schmitz, Norbert

    2010-01-01

    Purpose Salvage chemotherapy followed by high-dose therapy and autologous stem-cell transplantation (ASCT) is the standard treatment for relapsed diffuse large B-cell lymphoma (DLBCL). Salvage regimens have never been compared; their efficacy in the rituximab era is unknown. Patients and Methods Patients with CD20+ DLBCL in first relapse or who were refractory after first-line therapy were randomly assigned to either rituximab, ifosfamide, etoposide, and carboplatin (R-ICE) or rituximab, dexamethasone, high-dose cytarabine, and cisplatin (R-DHAP). Responding patients received high-dose chemotherapy and ASCT. Results The median age of the 396 patients enrolled (R-ICE, n = 202; R-DHAP, n = 194) was 55 years. Similar response rates were observed after three cycles of R-ICE (63.5%; 95% CI, 56% to 70%) and R-DHAP (62.8%; 95 CI, 55% to 69%). Factors affecting response rates (P < .001) were refractory disease/relapse less than versus more than 12 months after diagnosis (46% v 88%, respectively), International Prognostic Index (IPI) of more than 1 versus 0 to 1 (52% v 71%, respectively), and prior rituximab treatment versus no prior rituximab (51% v 83%, respectively). There was no significant difference between R-ICE and R-DHAP for 3-year event-free survival (EFS) or overall survival. Three-year EFS was affected by prior rituximab treatment versus no rituximab (21% v 47%, respectively), relapse less than versus more than 12 months after diagnosis (20% v 45%, respectively), and IPI of 2 to 3 versus 0 to 1 (18% v 40%, respectively). In the Cox model, these parameters were significant (P < .001). Conclusion In patients who experience relapse more than 12 months after diagnosis, prior rituximab treatment does not affect EFS. Patients with early relapses after rituximab-containing first-line therapy have a poor prognosis, with no difference between the effects of R-ICE and R-DHAP. PMID:20660832

  18. Rituximab for the treatment of IgG4-related orbital disease: experience from five cases

    PubMed Central

    Wu, A; Andrew, N H; Tsirbas, A; Tan, P; Gajdatsy, A; Selva, D

    2015-01-01

    Purpose To review the clinical efficacy and safety of rituximab for treatment of IgG4-related orbital disease (IgG4-ROD). Design Retrospective multicentre interventional case series. Methods Chart review for five cases of biopsy-confirmed IgG4-ROD (IgG4+>10/HPF, ratio of IgG4+/IgG+>40%) treated with rituximab. Information retrieved included the dosing schedule, adverse events and the magnitude, temporality, and duration of the clinical response. Results All cases of IgG4-ROD were either steroid dependent or steroid resistant. Rituximab doses for induction therapy included two doses of 1000 mg at 2-weekly intervals, and four doses at 375 mg/m2 at weekly intervals. Two months after starting rituximab, three cases achieved complete clinical resolution and two cases achieved partial clinical resolution. Complete radiological resolution occurred in one case, and partial radiological resolution in three cases. Three cases received rituximab maintenance therapy and one case was commenced on mycophenolate. No relapse occurred during a mean follow-up of 33 months (range: 7–65 months). One disease relapse occurred when the dosing interval of rituximab maintenance therapy was extended to 6–monthly intervals; remission was swiftly achieved with rituximab reinduction therapy. The only adverse effects reported were one episode of fatigue lasting 1 week and two episodes of orbital discomfort. Conclusion Rituximab may be an effective treatment option for IgG4-ROD that is steroid dependent or steroid intolerant. Rituximab therapy resulted in swift clinical and radiological improvement, many months free of relapse, and few side effects. PMID:25341435

  19. Rituximab maintenance after autologous stem cell transplantation prolongs response duration in non-naive rituximab follicular lymphoma patients: a single institution experience.

    PubMed

    Bourcier, J; Gastinne, T; Leux, C; Moreau, A; Bossard, C; Mahé, B; Blin, N; Dubruille, V; Touzeau, C; Voldoire, M; Guillaume, T; Peterlin, P; Gallas, P; Garnier, A; Maisonneuve, H; Moreau, P; Juge-Morineau, N; Jardel, H; Chevallier, P; Moreau, P; Le Gouill, S

    2016-08-01

    We retrospectively evaluated the role of rituximab (R) in maintenance treatment after autologous stem cell transplantation performed in patients with relapsed follicular lymphoma. We compared the outcome of 67 follicular lymphoma (FL) patients according to the use of rituximab maintenance (RM) or not. All patients received rituximab plus chemotherapy before autologous stem-cell transplantation (ASCT). Patients received median of two lines of prior therapy. The RM schedule was one injection of rituximab every 3 months for 2 years. Median follow-up is 4.6 years. The 3-year progression-free survival (PFS) after ASCT was 86 % with RM vs. 46 % without (p = 0.0045). Median is not reached in the RM arm vs. 31 months in non-RM arm. The 3-year OS was 96 % with RM vs. 78 % without (p = 0.059). The present monocentric study shows that 2 years of RM after ASCT significantly increases response duration for non-naive rituximab relapsed FL patients compared with observation. PMID:27297970

  20. Chimerism of buccal membrane cells in a monochorionic dizygotic twin.

    PubMed

    Fumoto, Seiko; Hosoi, Kenichiro; Ohnishi, Hiroaki; Hoshina, Hiroaki; Yan, Kunimasa; Saji, Hiroh; Oka, Akira

    2014-04-01

    No monochorionic dizygotic twins (MCDZTs) with cellular chimerism involving cells other than blood cells have been reported in the literature to date. Here we report a probable first case of MCDZTs with buccal cell chimerism. A 32-year-old woman conceived twins by in vitro fertilization by using 2 cryopreserved blastocysts that were transferred into her uterus. An ultrasound scan at 8 weeks' gestation showed signs indicative of monochorionic twins. A healthy boy and a healthy girl were born, showing no sexual ambiguity. Cytogenetic analyses and microsatellite studies demonstrated chimerism in blood cells of both twins. Notably, repeated fluorescence in situ hybridization and microsatellite studies revealed chimerism in buccal cells obtained from 1 of the twins. Although the mechanism through which buccal cell chimerism was generated remains to be elucidated, ectopic differentiation of chimeric hematopoietic cells that migrated to the buccal membrane or the cellular transfer between the 2 embryos at the early stage of development might be responsible for the phenomenon. This hypothesis raises an interesting issue regarding embryonic development and cellular differentiation into organs during fetal development. Given the possibility of cryptic chimerism in various organs including gonadal tissues in MCDZTs, close observation will be required to determine whether complications develop in the course of the patients' growth. PMID:24685957

  1. Clinical responses to rituximab in a case of neuroblastoma with refractory opsoclonus myoclonus ataxia syndrome.

    PubMed

    Alavi, Samin; Kord Valeshabad, Ali; Moradveisi, Borhan; Aminasnafi, Ali; Arzanian, Mohammad Taghi

    2012-01-01

    Opsoclonus myoclonus ataxia syndrome (OMS) is a rare neurologic syndrome. In a high proportion of children, it is associated with neuroblastoma. The etiology of this condition is thought to be immune mediated. In children, immunotherapy with conventional treatments such as corticosteroids, intravenous immunoglobulin, adrenocorticotropic hormone, and even antiepileptic drugs has been tried. Recently rituximab has been used safely for refractory OMS in children with neuroblastoma. Our patient was a 3.5-year-old girl referred for ataxia and dancing eye movements starting since 1.5 years ago. She was diagnosed with neuroblastoma on imaging studies on admission. The OMS was refractory to surgical resection, chemotherapy, corticosteroids, and intravenous immunoglobulin. Patient received rituximab simultaneously with chemotherapy. The total severity score decreased by 61.1% after rituximab. Patient's ataxia markedly improved that she was able to walk independently after 6 months. Our case confirmed the clinical efficacy and safety of rituximab in a refractory case of OMS. PMID:23198199

  2. Persistence of babesiosis for >2 years in a patient on rituximab for rheumatoid arthritis.

    PubMed

    Raffalli, John; Wormser, Gary P

    2016-06-01

    We report a patient who was being treated with rituximab for rheumatoid arthritis who developed Babesia microti infection that persisted for 26 months despite prolonged anti-babesia drug therapy. The explanation for the persistence was likely to have been the long-term immunocompromising effects of rituximab, as evidenced by seronegativity for B. microti antibodies that lasted for more than 1 year after onset of infection. PMID:27036977

  3. Retrospective analysis of rituximab therapy and splenectomy in childhood chronic and refractory immune thrombocytopenic purpura.

    PubMed

    Ay, Yilmaz; Karapinar, Tuba H; Oymak, Yesim; Toret, Ersin; Demirag, Bengu; Ince, Dilek; Ozcan, Esin; Moueminoglou, Nergial; Koker, Sultan A; Vergin, Canan

    2016-06-01

    Immune thrombocytopenic purpura (ITP) results from accelerated platelet destruction mediated by autoantibodies to platelet glycoproteins. Some patients with chronic ITP are refractory to all therapies [steroids, intravenous immunoglobulin (IVIG), anti-D and immunosuppresive drugs] and have chronic low platelet counts and episodic bleeding. We retrospectively evaluated the efficacy and safety of rituximab treatment and splenectomy in paediatric patients diagnosed with chronic and refractory ITP who were unresponsive to steroids, IVIG, cyclosporine and mycophenolate mofetil. Records of patients with chronic and refractory ITP in 459 patients with primary ITP who were followed up in our hospital from January 2005 to December 2014 were reviewed. Fifteen of patients received rituximab and/or applied splenectomy. Fifteen chronic ITP patients (10 boys, five girls) with a mean age of 10 years were enrolled in the study. Two of these patients were suffering from Evans syndrome. The median time since diagnosis of ITP was 10 years. The median follow-up duration after starting Rituximab and splenectomy were 13 and 9.5 months, respectively.None of the seven patients who were treated with rituximab achieved a response. A splenectomy was performed in six of the seven patients who had been treated with rituximab. Complete and partial responses were achieved in 67 and 33% of the patients, respectively. We evaluated the clinical characteristics and responses of chronic ITP patients who did not receive rituximab therapy and underwent a splenectomy. The success rate was 100% in the eight patients with chronic and refractory ITP. Rituximab therapy might not be beneficial for some children with severe chronic ITP who are refractory to standard agents. A splenectomy might be useful and preferable to rituximab. PMID:26656905

  4. Combination of cyclophosphamide, rituximab, and intratumoral CpG oligodeoxynucleotide successfully eradicates established B cell lymphoma.

    PubMed

    Betting, David J; Hurvitz, Sara A; Steward, Kristopher K; Yamada, Reiko E; Kafi, Kamran; van Rooijen, Nico; Timmerman, John M

    2012-09-01

    Rituximab plus chemotherapy is standard therapy for patients with non-Hodgkin B cell lymphoma, but often complete response or cure is not achieved. Toll-like receptor 9 agonist CpG oligodeoxynucleotides (CpG) can improve antibody-dependent cellular cytotoxicity and adaptive antitumor immune responses. Using a syngeneic murine B cell lymphoma expressing human CD20 (38C13-huCD20), we previously demonstrated that rituximab plus intratumoral CpG, but not systemic CpG, could eradicate up to half of 7-day established 38C13-huCD20 tumors. However, larger 10-day established tumors could not be cured with this regimen. We thus hypothesized that cytoreduction with cyclophosphamide (Cy) before immunotherapy might permit eradication of these more advanced tumor burdens. Pretreatment with Cy resulted in tumor eradication from 83% of animals treated with rituximab/CpG, whereas Cy/CpG or Cy/rituximab treatments only cured 30% or 17%, respectively (P<0.005). Tumor eradication depended on natural killer cells, but not T cells, macrophages, or complement. Only mice treated with Cy/rituximab/CpG partially resisted rechallenge with tumor cells. Foxp3 Treg and CD11bGr1 myeloid suppressor cells persisted within lymphoid organs after therapy, possibly influencing the ability to establish adaptive tumor immunity. In conclusion, cytoreduction with Cy permitted the cure of large, established lymphomas not otherwise responsive to rituximab plus intratumoral CpG immunotherapy. PMID:22892450

  5. Use of Rituximab in Children with Steroid- and Calcineurin-Inhibitor-Dependent Idiopathic Nephrotic Syndrome

    PubMed Central

    Ravani, Pietro; Ponticelli, Alessandro; Siciliano, Chiara; Fornoni, Alessia; Magnasco, Alberto; Sica, Felice; Bodria, Monica; Caridi, Gianluca; Wei, Changli; Belingheri, Mirco; Ghio, Luciana; Merscher-Gomez, Sandra; Edefonti, Alberto; Pasini, Andrea; Montini, Giovanni; Murtas, Corrado; Wang, Xiangyu; Muruve, Daniel; Vaglio, Augusto; Martorana, Davide; Pani, Antonello; Scolari, Francesco; Reiser, Jochen; Ghiggeri, Gian Marco

    2013-01-01

    In children with idiopathic nephrotic syndrome rituximab can maintain short-term remission with withdrawal of prednisone and calcineurin-inhibitors. Long-term effects including number of repeated infusions to maintain remission are unknown. We treated with rituximab 46 consecutive children with idiopathic nephrotic syndrome lasting for at least one year (6.3±4.1 years), who were maintained in remission with oral prednisone and calcineurin inhibitors. They received 1–5 rituximab courses during a median follow-up of three years (range 1–5). Oral agents were tapered after each infusion, and completely withdrawn within 45 days. Rituximab was well tolerated. Six-month probabilities of remission were 48% after the first infusion and 37% after subsequent infusions. One- and two-year-remission probabilities were respectively 20% and 10%. Median time intervals between complete oral-agent withdrawal and relapse were 5.6 and 8.5 months respectively following the first and subsequent courses. Time to reconstitution of CD20 cells correlated with the duration of remission, but was not associated with variation in FcyR, CD20 or SMPDL-3B polymorphisms. Podocyte Src phosphorylation was normal. Rituximab can be safely and repeatedly used as prednisone and calcineurin-inhibitor-sparing therapy in a considerable proportion of children with dependent forms of idiopathic nephrotic syndrome. Further research is needed to identify patients who will benefit most from rituximab therapy. PMID:23739238

  6. Use of Rituximab for Refractory Cytopenias Associated with Autoimmune Lymphoproliferative Syndrome (ALPS)

    PubMed Central

    Rao, V. Koneti; Price, Susan; Perkins, Katie; Aldridge, Patricia; Tretler, Jean; Davis, Joie; Dale, Janet K.; Gill, Fred; Hartman, Kip R.; Stork, Linda C.; Gnarra, David J.; Krishnamurti, Lakshmanan; Newburger, Peter E.; Puck, Jennifer; Fleisher, Thomas

    2009-01-01

    Background ALPS is a disorder of apoptosis resulting in accumulation of autoreactive lymphocytes, leading to marked lymphadenopathy, hepatosplenomegaly and multilineage cytopenias due to splenic sequestration and/or autoimmune destruction often presenting in childhood. We summarize our experience of rituximab use during the last 8 years in twelve patients, 9 children and 3 adults, out of 259 individuals with ALPS, belonging to 166 families currently enrolled in studies at the National Institutes of Health. Methods Refractory immune thrombocytopenia (platelet count <20,000) in 9 patients and autoimmune hemolytic anemia (AIHA) in 3 patients led to treatment with rituximab. Among them, 7 patients had undergone prior surgical splenectomy; 3 had significant splenomegaly; and 2 had no palpable spleen. Results In 7 out of 9 patients with ALPS and thrombocytopenia, rituximab therapy led to median response duration of 21months (range 14–36 months). In contrast, none of the 3 children treated with rituximab for AIHA responded. Noted toxicities included profound and prolonged hypogammaglobulinemia in 3 patients requiring replacement IVIG, total absence of antibody response to polysaccharide vaccines lasting up to 4 years after rituximab infusions in 1 patient and prolonged neutropenia in 1 patient. Conclusion Toxicities including hypogammaglobulinemia and neutropenia constitute an additional infection risk burden, especially in asplenic individuals, and may warrant avoidance of rituximab until other immunosuppressive medication options are exhausted. Long term follow up of ALPS patients with cytopenias after any treatment is necessary to determine relative risks and benefits. PMID:19214977

  7. Subcutaneous versus intravenous administration of rituximab: pharmacokinetics, CD20 target coverage and B-cell depletion in cynomolgus monkeys.

    PubMed

    Mao, Cheng-Ping; Brovarney, Martin R; Dabbagh, Karim; Birnböck, Herbert F; Richter, Wolfgang F; Del Nagro, Christopher J

    2013-01-01

    The CD20-specific monoclonal antibody rituximab (MabThera(®), Rituxan(®)) is widely used as the backbone of treatment for patients with hematologic disorders. Intravenous administration of rituximab is associated with infusion times of 4-6 hours, and can be associated with infusion-related reactions. Subcutaneous administration of rituximab may reduce this and facilitate administration without infusion-related reactions. We sought to determine the feasibility of achieving equivalent efficacy (measured by endogenous B-cell depletion) and long-term durability of CD20 target coverage for subcutaneously administered rituximab compared with intravenous dosing. In these preclinical studies, male cynomolgus monkeys were treated with either intravenous rituximab or novel subcutaneous formulation of rituximab containing human recombinant DNA-derived hyaluronidase enzyme. Peripheral blood samples were analyzed for serum rituximab concentrations, peripheral B-cell depletion, and CD20 target coverage, including subset analysis according to CD21+ status. Distal lymph node B-cell depletion and CD20 target coverage were also measured. Initial peak serum concentrations of rituximab were significantly higher following intravenous administration than subcutaneous. However, the mean serum rituximab trough concentrations were comparable at 2 and 7 days post-first dose and 9 and 14 days post-second dose. Efficacy of B-cell depletion in both peripheral blood and distal lymph nodes was comparable for both methods. In lymph nodes, 9 days after the second dose with subcutaneous and intravenous rituximab, B-cell levels were decreased by 57% and 42% respectively. Similarly, levels of peripheral blood B cells were depleted by >94% for both subcutaneous and intravenous dosing at all time points. Long-term recovery of free unbound surface CD20 levels was similar, and the duration of B-cell depletion was equally sustained over 2 months for both methods. These results demonstrate that, despite

  8. Subcutaneous versus Intravenous Administration of Rituximab: Pharmacokinetics, CD20 Target Coverage and B-Cell Depletion in Cynomolgus Monkeys

    PubMed Central

    Mao, Cheng-Ping; Brovarney, Martin R.; Dabbagh, Karim; Birnböck, Herbert F.; Richter, Wolfgang F.; Del Nagro, Christopher J.

    2013-01-01

    The CD20-specific monoclonal antibody rituximab (MabThera®, Rituxan®) is widely used as the backbone of treatment for patients with hematologic disorders. Intravenous administration of rituximab is associated with infusion times of 4–6 hours, and can be associated with infusion-related reactions. Subcutaneous administration of rituximab may reduce this and facilitate administration without infusion-related reactions. We sought to determine the feasibility of achieving equivalent efficacy (measured by endogenous B-cell depletion) and long-term durability of CD20 target coverage for subcutaneously administered rituximab compared with intravenous dosing. In these preclinical studies, male cynomolgus monkeys were treated with either intravenous rituximab or novel subcutaneous formulation of rituximab containing human recombinant DNA-derived hyaluronidase enzyme. Peripheral blood samples were analyzed for serum rituximab concentrations, peripheral B-cell depletion, and CD20 target coverage, including subset analysis according to CD21+ status. Distal lymph node B-cell depletion and CD20 target coverage were also measured. Initial peak serum concentrations of rituximab were significantly higher following intravenous administration than subcutaneous. However, the mean serum rituximab trough concentrations were comparable at 2 and 7 days post-first dose and 9 and 14 days post-second dose. Efficacy of B-cell depletion in both peripheral blood and distal lymph nodes was comparable for both methods. In lymph nodes, 9 days after the second dose with subcutaneous and intravenous rituximab, B-cell levels were decreased by 57% and 42% respectively. Similarly, levels of peripheral blood B cells were depleted by >94% for both subcutaneous and intravenous dosing at all time points. Long-term recovery of free unbound surface CD20 levels was similar, and the duration of B-cell depletion was equally sustained over 2 months for both methods. These results demonstrate that, despite

  9. Chimerism in piglets developed from aggregated cloned embryos.

    PubMed

    Huang, Yongye; Li, Zhanjun; Wang, Anfeng; Han, Xiaolei; Song, Yuning; Yuan, Lin; Li, Tianye; Wang, Bing; Lai, Liangxue; Ouyang, Hongsheng; Pang, Daxin

    2016-04-01

    Porcine chimeras are valuable in the study of pluripotency, embryogenesis and development. It would be meaningful to generate chimeric piglets from somatic cell nuclear transfer embryos. In this study, two cell lines expressing the fluorescent markers enhanced green fluorescent protein (EGFP) and tdTomato were used as donor cells to produce reconstructed embryos. Chimeric embryos were generated by aggregating two EGFP-cell derived embryos with two tdTomato-cell derived embryos at the 4-cell stage, and embryo transfer was performed when the aggregated embryos developed into blastocysts. Live porcine chimeras were successfully born and chimerism was observed by their skin color, gene integration, microsatellite loci composition and fluorescent protein expression. The chimeric piglets were largely composed of EGFP-expressing cells, and this phenomenon was possibly due to the hyper-methylation of the promoter of the tdTomato gene. In addition, the expression levels of tumorigenicity-related genes were altered after tdTomato transfection in bladder cancer cells. The results show that chimeric pigs can be produced by aggregating cloned embryos and that the developmental capability of the cloned embryo in the subsequent chimeric development could be affected by the growth characteristics of its donor cell. PMID:27239442

  10. Changes in B and T lymphocytes and chemokines with rituximab treatment in multiple sclerosis

    PubMed Central

    Piccio, Laura; Naismith, Robert T.; Trinkaus, Kathryn; Klein, Robyn S.; Parks, Becky J.; Lyons, Jeri A.; Cross, Anne H.

    2010-01-01

    Background B cells are implicated in the pathogenesis of multiple sclerosis (MS). A beneficial effect of B cell depletion using rituximab has been shown, but the complete mechanism of action for this drug is unclear. Objective To determine the relationship between T cells, B cells, and changes in CSF chemokines with rituximab, a monoclonal antibody that targets CD20. Design Phase II trial of rituximab as an add-on therapy. Setting The John L. Multiple Sclerosis Center, Washington University, St. Louis, Missouri. Patients Thirty relapsing-remitting MS subjects with clinical and MRI activity despite treatment with an immunomodulatory drug received four weekly doses of 375mg/m2 rituximab. Main Outcome Measures Lumbar puncture was performed before and after rituximab infusions in 26 subjects. CSF B and T lymphocytes were enumerated by flow cytometry, and chemoattractants were measured by ELISA. Results After rituximab administration, CSF B cells were decreased or undetectable in all subjects and CSF T cells were reduced in 81% of subjects. The mean reduction in CSF cellularity was 95% for B cells and 50% for T cells. After rituximab infusion, CSF CXCL13 and CCL19 decreased (P= 0.002, P=0.03, respectively). The proportional decline in CSF T cells correlated with the proportional decrease in CXCL13 (r=0.45;P=0.03), suggesting a possible relationship. CSF IgG index, IgG concentration, and oligoclonal band number were unchanged following treatment. Conclusions B cells are critical for T cell trafficking into the CNS in MS patients, and may alter T cell trafficking by influencing chemokine production within the CNS. PMID:20558389

  11. CHIMERIC ALPHAVIRUS VACCINE CANDIDATES FOR CHIKUNGUNYA

    PubMed Central

    Wang, Eryu; Volkova, Eugenia; Adams, A. Paige; Forrester, Naomi; Xiao, Shu-Yuan; Frolov, Ilya; Weaver, Scott C.

    2008-01-01

    Chikungunya virus (CHIKV) is an emerging alphavirus that has caused major epidemics in India and islands off the east coast of Africa since 2005. Importations into Europe and the Americas, including one that led to epidemic transmission in Italy during 2007, underscore the risk of endemic establishment elsewhere. Because there is no licensed human vaccine, and an attenuated Investigational New Drug product developed by the U.S. Army causes mild arthritis in some vaccinees, we developed chimeric alphavirus vaccine candidates using either Venezuelan equine encephalitis attenuated vaccine strain TC-83, a naturally attenuated strain of eastern equine encephalitis virus (EEEV), or Sindbis virus as a backbone and the structural protein genes of CHIKV. All vaccine candidates replicated efficiently in cell cultures, and were highly attenuated in mice. All of the chimeras also produced robust neutralizing antibody responses, although the TC-83 and EEEV backbones appeared to offer greater immunogenicity. Vaccinated mice were fully protected against disease and viremia after CHIKV challenge. PMID:18692107

  12. Rituximab for subcutaneous delivery: Clinical management principles from a nursing perspective.

    PubMed

    Carlson, Julia; Cox, Keith; Bedwell, Kylie; Ku, Mathew

    2015-12-01

    Nurses play an integral role in administering treatments to patients with non-Hodgkin's lymphomas. Intravenous (IV) rituximab was approved by the Australian Therapeutic Goods Administration in 1998, and a novel subcutaneous (SC) formulation was approved in 2014. Fixed-dose SC rituximab is highly concentrated; co-formulation with a fully human recombinant vorhyaluronidase alfa enzyme helps overcome the physiological barriers of the SC space, facilitating drug dispersion. Despite a different pharmacokinetic profile to the IV preparation, SC rituximab demonstrates a comparable efficacy/safety profile. Most frequently occurring rituximab-related adverse events include neutropenia, nausea and constipation, and administration-related reactions are more frequent with the SC preparation. Compared with IV, SC delivery reduces treatment times and nurse workload, and patients report greater comfort and convenience. This article sets out nursing considerations for optimal administration of SC rituximab, including premedication, drug handling/preparation, injection technique, after-care and management of adverse events, particularly administration-related reactions. PMID:26681664

  13. Successful rituximab treatment in an elderly patient with recurrent thrombotic thrombocytopenic purpura.

    PubMed

    Matsubara, Etsuko; Yamanouchi, Jun; Hato, Takaaki; Takeuchi, Kazuto; Niiya, Toshiyuki; Yasukawa, Masaki

    2016-07-01

    An 81-year-old man presenting with fever, neurological symptoms, thrombocytopenia, and hemolytic anemia was diagnosed with acquired idiopathic thrombotic thrombocytopenic purpura (TTP). His disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) activity was <1% and the ADAMTS13 inhibitor titer was 3.2 BU/ml. He received plasma exchange and steroid administration until remission was achieved. Seven months later, he suffered from paralysis of the right hand, hemolytic anemia, and thrombocytopenia. We confirmed TTP recurrence based on ADAMTS13 activity <1% and an ADAMTS13 inhibitor titer of 19.4 BU/ml. Four infusions of rituximab were administered in addition to plasma exchange and steroid pulse therapy. Platelet count recovery was observed within 5 days. No severe side effects related to rituximab occurred. Although rituximab has not been approved for TTP in Japan, we report the efficacy and safety of rituximab in an elderly patient with recurrent TTP. We suggest that rituximab therapy should be started as soon as possible for recurrent TTP in patients with high titers of ADAMTS13 inhibitor. PMID:27498731

  14. Rituximab for Non-Hodgkin’s Lymphoma: A Story of Rapid Success in Translation

    PubMed Central

    Harrison, Andrew M.; Thalji, Nassir M.; Greenberg, Alexandra J.; Tapia, Carmen J.; Windebank, Anthony J.

    2014-01-01

    Translational stories range from straightforward to complex. In this commentary, the story of the rapid and successful translation of rituximab therapy for the treatment of non-Hodgkin’s lymphoma (NHL) is examined. Development of this monoclonal antibody therapy began in the late 1980s. In 1994, rituximab received its first approval for the treatment of NHL by the United States Food and Drug Administration (FDA). Rituximab has since been approved for additional indications and has transformed medical practice. However, the social and political implications of these rapid successes are only beginning to become clear. In this commentary, key events in the rapid translation of rituximab from the bench to bedside are highlighted and placed into this historical framework. To accomplish this, the story of rituximab is divided into the following six topics, which we believe to be widely applicable to case studies of translation: (1) underlying disease, (2) key basic science, (3) key clinical studies in translation, (4) FDA approval process, (5) changes to medical practice, and (6) the social and political influences on translation. PMID:24528902

  15. Timing determines dexamethasone and rituximab induced synergistic cell death.

    PubMed

    Adem, Jemal; Eray, Mine; Eeva, Jonna; Nuutinen, Ulla; Pelkonen, Jukka

    2016-07-01

    Dysregulation of cell death signaling pathways in many cell types such as B lymphocytes (B-cells) can lead to cancer, for example to B-cell lymphomas. Rituximab (RTX) and glucocorticoids such as dexamethasone (Dex) are widely used to treat hematological malignancies including B-cell lymphomas. Although the combination of Dex and RTX improves the treatment outcome of lymphoma patients, most lymphomas remain incurable diseases. Therefore, a detailed investigation of Dex- and RTX-induced signaling might provide new insights into the therapeutic benefits of these drugs. In this paper, we describe Dex- and RTX-induced signaling pathways and their downstream target proteins/cells. In addition, we also overview how the signaling initiated by Dex and RTX modulate the outcome of Dex- and RTX-mediated cell death in lymphoma cells. The combination of Dex and RTX results in massive cell death in lymphoma cells. However, pretreatment of lymphoma cells or mononuclear cytotoxic cells with Dex followed by RTX leads to a decrease in apoptosis or it impairs antibody-dependent cellular cytotoxicity (ADCC). RTX-mediated ADCC is impaired by Dex-induced depletion of cytotoxic cells, whereas RTX-mediated short-term ERK1/2 activation decreases Dex-induced apoptosis. Therefore, the timing of the combination of Dex and RTX is a determining factor for the synergistic effect of these cell death inducing agents. PMID:27290654

  16. Chimeric autologous/allogeneic constructs for skin regeneration.

    PubMed

    Rasmussen, Cathy Ann; Tam, Joshua; Steiglitz, Barry M; Bauer, Rebecca L; Peters, Noel R; Wang, Ying; Anderson, R Rox; Allen-Hoffmann, B Lynn

    2014-08-01

    The ideal treatment for severe cutaneous injuries would eliminate the need for autografts and promote fully functional, aesthetically pleasing autologous skin regeneration. NIKS progenitor cell-based skin tissues have been developed to promote healing by providing barrier function and delivering wound healing factors. Independently, a device has recently been created to "copy" skin by harvesting full-thickness microscopic tissue columns (MTCs) in lieu of autografts traditionally harvested as sheets. We evaluated the feasibility of combining these two technologies by embedding MTCs in NIKS-based skin tissues to generate chimeric autologous/allogeneic constructs. Chimeric constructs have the potential to provide immediate wound coverage, eliminate painful donor site wounds, and promote restoration of a pigmented skin tissue possessing hair follicles, sweat glands, and sebaceous glands. After MTC insertion, chimeric constructs and controls were reintroduced into air-interface culture and maintained in vitro for several weeks. Tissue viability, proliferative capacity, and morphology were evaluated after long-term culture. Our results confirmed successful MTC insertion and integration, and demonstrated the feasibility of generating chimeric autologous/allogeneic constructs that preserved the viability, proliferative capacity, and structure of autologous pigmented skin. These feasibility studies established the proof-of-principle necessary to further develop chimeric autologous/allogeneic constructs for the treatment of complex skin defects. PMID:25102552

  17. Steroid metabolism in chimeric mice with humanized liver.

    PubMed

    Lootens, Leen; Van Eenoo, Peter; Meuleman, Philip; Pozo, Oscar J; Van Renterghem, Pieter; Leroux-Roels, Geert; Delbeke, Frans T

    2009-11-01

    Anabolic androgenic steroids are considered to be doping agents and are prohibited in sports. Their metabolism needs to be elucidated to allow for urinary detection by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). Steroid metabolism was assessed using uPA(+/+) SCID mice with humanized livers (chimeric mice). This study presents the results of 19-norandrost-4-ene-3,17-dione (19-norAD) administration to these in vivo mice. As in humans, 19-norandrosterone and 19-noretiocholanolone are the major detectable metabolites of 19-norAD in the urine of chimeric mice.A summary is given of the metabolic pathways found in chimeric mice after administration of three model steroid compounds (methandienone, androst-4-ene-3,17-dione and 19-norandrost-4-ene-3,17-dione). From these studies we can conclude that all major metabolic pathways for anabolic steroids in humans are present in the chimeric mouse. It is hoped that, in future, this promising chimeric mouse model might assist the discovery of new and possible longer detectable metabolites of (designer) steroids. PMID:20355169

  18. Selective response to rituximab in a young child with MuSK-associated myasthenia gravis.

    PubMed

    Govindarajan, Raghav; Iyadurai, Stanley J; Connolly, Anne; Zaidman, Craig

    2015-08-01

    Neuromuscular junction disorders in children are either genetic, such as congenital myasthenic syndrome, or autoimmune with circulating antibodies most commonly against acetylcholine receptors. There is limited experience recognizing and treating children with myasthenia associated with muscle-specific tyrosine kinase antibodies. We report a seven-year-old child with intermittent esotropia since age 3 months, and two years of progressive and severe diplopia, dysarthria, dysphagia, and facial weakness. Acetylcholine receptor antibodies and genetic testing for congenital myasthenic syndrome were negative. Muscle specific tyrosine kinase antibodies were significantly elevated. Ophthalmoplegia and bulbar weakness were refractory to treatment with acetylcholinesterase inhibitors, corticosteroids and IVIg but completely resolved following treatment with rituximab. Her neurologic examination remained normal at the most recent follow-up, 15 months after initiation of rituximab. Children with MuSK myasthenia, like adults, can respond to rituximab despite long standing disease and failure to improve on other immunosuppressant medications. PMID:25998611

  19. Rituximab treatment for Epstein-Barr virus DNAemia after alternative-donor hematopoietic stem cell transplantation.

    PubMed

    Coppoletta, Stefania; Tedone, Elisabetta; Galano, Barbara; Soracco, Monica; Raiola, Anna Maria; Lamparelli, Teresa; Gualandi, Francesca; Bregante, Stefania; Ibatici, Adalberto; di Grazia, Carmen; Dominietto, Alida; Varaldo, Riccardo; Bruno, Barbara; Frassoni, Francesco; Van Lint, Maria Teresa; Bacigalupo, Andrea

    2011-06-01

    We report 55 patients undergoing an alternative-donor hematopoietic stem cell transplantation (HSCT) who developed Epstein-Barr virus (EBV) DNAemia, with >1000 EBV copies/10(5) peripheral blood mononuclear cells (PBMCs), and were treated with rituximab (375 mg/m(2)). The median patient age was 47 years (range, 20-65 years), and graft sources were mismatched family members (n = 4), unrelated donors (n = 46), and unrelated cord blood (n = 5). The conditioning regimen included antithymocyte globulin (ATG) in all patients. The median time to development of EBV DNAemia was day 27 post-HSCT (range, day 5 to day 242), with a median of 60 EBV copies/10(5) PBMCs (range, 1-5770 copies/10(5) PBMCs). The number of EBV copies was reduced to <1000/10(5) PBMCs on day +7 after initiation of rituximab therapy in 51% of the patients, on day +14 in 73% of the patients, and on +21 in 92% of the patients. Overall, 50 of 55 patients (91%) cleared EBV after one dose (n = 25) or more than one dose (n = 25) of rituximab. Factors predicting transplantation-related mortality (TRM) in multivariate analysis were a reduction to <1000 EBV copies/10(5) PBMCs by day +7 of treatment (relative risk [RR], 0.2; P = .01) and disease phase in remission (RR, 0.3; P = .05). TRM was 23% in the 40 patients with none or one of the negative predictors and 60% in the 15 patients with both negative predictors (P = .001). Of these latter 15 patients, 3 developed clinical posttransplantation lymphoproliferative disorder (PTLD). All 3 of these patients had a high EBV load on day +7 of rituximab therapy. This study confirms the effectiveness of rituximab in controlling EBV DNAemia in patients undergoing allogeneic HSCT. Patients with increasing EBV copies despite rituximab therapy are at high risk for EBV PTLD and may be considered for alternative therapies. PMID:20950702

  20. Chimeric antigen receptors: driving immunology towards synthetic biology.

    PubMed

    Sadelain, Michel

    2016-08-01

    The advent of second generation chimeric antigen receptors and the CD19 paradigm have ushered a new therapeutic modality in oncology. In contrast to earlier forms of adoptive cell therapy, which were based on the isolation and expansion of naturally occurring T cells, CAR therapy is based on the design and manufacture of engineered T cells with optimized properties. A new armamentarium, comprising not only CARs but also chimeric costimulatory receptors, chimeric cytokine receptors, inhibitory receptors and synthetic Notch receptors, expressed in naïve, central memory or stem cell-like memory T cells, is being developed for clinical use in a wide range of cancers. Immunological principles are thus finding a new purpose thanks to advances in genetic engineering, synthetic biology and cell manufacturing sciences. PMID:27372731

  1. Long-term remission with rituximab in refractory leucine-rich glioma inactivated 1 antibody encephalitis.

    PubMed

    Brown, J William L; Martin, Peter J; Thorpe, John W; Michell, Andrew W; Coles, Alasdair J; Cox, Amanda L; Vincent, Angela; Zandi, Michael S

    2014-06-15

    Autoimmune encephalitis associated with antibodies to leucine-rich glioma inactivated 1 (LGI1) is recently described and there is a lack of detailed reports on the treatment of relapsing or refractory cases and long-term outcomes. Two case reports are presented. Both cases had faciobrachial dystonic seizures (FBDS) and received rituximab after relapsing or refractory disease. Both cases achieved sustained clinical remission of up to 15 and 56 months respectively. Rituximab use allowed withdrawal of corticosteroids and was well tolerated. Randomized clinical trials are needed in LGI1 encephalitis and other autoimmune encephalitides. PMID:24703099

  2. Sustained Elite Suppression of Replication Competent HIV-1 in a Patient Treated With Rituximab Based Chemotherapy

    PubMed Central

    Gaillard, Stephanie; Dinoso, Jason B.; Marsh, Julia A.; DeZern, Amy E.; O’Connell, Karen A; Spivak, Adam M.; Alwood, Karla; Durand, Christine M.; Ambinder, Richard F.; Blankson, Joel N.

    2011-01-01

    The mechanism of elite control of HIV-1 replication is not fully understood. While immunosuppression due to rituximab based chemotherapy has been associated with increased replication of HBV, CMV, and HIV-1, control of replication-competent HIV-1 was maintained in an elite controller/suppressor treated with a regimen that included vincristine, cyclophosphamide, prednisone, four rounds of plasmapheresis and ten cycles of rituximab. The data suggests that de-novo antibody responses do not play a significant role in the control of viral replication in these patients. PMID:21550842

  3. A Novel Self-Replicating Chimeric Lentivirus-Like Particle

    PubMed Central

    Young, Kelly R.; Madden, Victoria J.; Johnson, Philip R.; Johnston, Robert E.

    2012-01-01

    Successful live attenuated vaccines mimic natural exposure to pathogens without causing disease and have been successful against several viruses. However, safety concerns prevent the development of attenuated human immunodeficiency virus (HIV) as a vaccine candidate. If a safe, replicating virus vaccine could be developed, it might have the potential to offer significant protection against HIV infection and disease. Described here is the development of a novel self-replicating chimeric virus vaccine candidate that is designed to provide natural exposure to a lentivirus-like particle and to incorporate the properties of a live attenuated virus vaccine without the inherent safety issues associated with attenuated lentiviruses. The genome from the alphavirus Venezuelan equine encephalitis virus (VEE) was modified to express SHIV89.6P genes encoding the structural proteins Gag and Env. Expression of Gag and Env from VEE RNA in primate cells led to the assembly of particles that morphologically and functionally resembled lentivirus virions and that incorporated alphavirus RNA. Infection of CD4+ cells with chimeric lentivirus-like particles was specific and productive, resulting in RNA replication, expression of Gag and Env, and generation of progeny chimeric particles. Further genome modifications designed to enhance encapsidation of the chimeric virus genome and to express an attenuated simian immunodeficiency virus (SIV) protease for particle maturation improved the ability of chimeric lentivirus-like particles to propagate in cell culture. This study provides proof of concept for the feasibility of creating chimeric virus genomes that express lentivirus structural proteins and assemble into infectious particles for presentation of lentivirus immunogens in their native and functional conformation. PMID:22013035

  4. t(11;18)(q21;q21)-positive advanced-stage MALT lymphoma associated with monoclonal gammopathy: resistance to rituximab or rituximab-containing chemotherapy.

    PubMed

    Ohno, Hitoshi; Isoda, Kotaro

    2008-11-01

    Here we describe two cases of mucosa-associated lymphoid tissue (MALT) lymphoma with monoclonal immunoglobulins (Igs). The first case was a 77-year-old man with primary lymphoma of the lung. Immunoelectrophoresis detected IgM-kappa in serum and kappa light chain excretion into urine. Three months after treatment with single-agent rituximab, a large amount of pleural fluid was found to have accumulated. The fluid contained CD5(-), CD10(-), CD19(+), CD38(+) and CD138(-/+) lymphoma cells with lymphoplasmacytoid appearance. Although a small fraction of the cells were CD20(+), the majority of the lymphoma cells were negative and expressed surface-membrane IgM-kappa at low levels. The cells possessed a karyotype of 46, XY, t(11;18)(q21;q21). The second case was a 55-year-old man who underwent total gastrectomy due to gastric perforation. Surgical specimens demonstrated the histopathological features of MALT lymphoma associated with plasma cell differentiation. The lymphoma cells had a 46, XY, t(11;18)(q21;q21) karyotype. Monoclonal Igs detected were serum IgA (M)-kappa and urinary kappa light chain. The patient was subsequently treated with six cycles of R-CVP (rituximab, cyclophosphamide, vincristine and prednisolone) ; however, serum monoclonal Ig levels were not affected. The lymphoma cells in both cases may have contained two populations, a rituximab-sensitive CD20(+) population and a rituximab-resistant population that had differentiated into the Ig-secreting plasma cell stage. PMID:19039196

  5. A phase 2 study of Rituximab-Bendamustine and Rituximab-Cytarabine for transplant-eligible patients with mantle cell lymphoma.

    PubMed

    Armand, Philippe; Redd, Robert; Bsat, Jad; Mayuram, Sangeetha; Giardino, Angela; Fisher, David C; LaCasce, Ann S; Jacobson, Caron; Davids, Matthew S; Brown, Jennifer R; Weng, Li; Wilkins, Jennifer; Faham, Malek; Freedman, Arnold S; Joyce, Robin; Jacobsen, Eric D

    2016-04-01

    Chemoimmunotherapy followed by autologous stem cell transplantation (ASCT) is a standard therapy for transplant-eligible patients with newly diagnosed mantle cell lymphoma (MCL). The achievement of complete remission (CR) and minimal residual disease (MRD) negativity are associated with better outcomes. We tested an induction regimen of rituximab/bendamustine followed by rituximab/high-dose cytarabine (RB/RC). This phase 2 study (NCT01661881) enrolled 23 transplant-eligible patients aged 42-69, of whom 70% were MCL international prognostic index low-risk. Patients received three cycles of RB followed by three cycles of RC. The primary endpoint of the trial was the rate of CR after six cycles of therapy, with a rate of 75% considered promising. 96% of patients achieved a CR/unconfirmed CR after treatment, meeting the primary objective. One patient progressed on study, one declined ASCT in CR, and the remaining 21 underwent successful stem cell collection and ASCT. After a median follow-up of 13 months, the progression-free survival rate was 96%. Among 15 MRD-evaluable patients who completed treatment, 93% achieved MRD negativity after RB/RC. In conclusion, RB/RC achieves very high CR and MRD negativity rates in transplant-eligible patients, with a favourable safety profile. RB/RC warrants further comparative studies, and may become a useful alternative to RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone)-based induction regimens in this patient population. PMID:26729345

  6. A case of canine chimerism diagnosed using coat color tests.

    PubMed

    Dreger, Dayna L; Schmutz, Sheila M

    2012-12-01

    Through the use of PCR based coat color tests, we were able to diagnose a dog that exhibits an unusual coat color phenotype as an XX/XX chimera. Coat color alleles vary widely among dog breeds, presenting a novel method for detecting chimerism using diagnostic tests for known coat color alleles. PMID:22433982

  7. Occurrence of lymphoplasmacytic lymphoma 6 years after amelioration of primary cold agglutinin disease by rituximab therapy.

    PubMed

    Tanaka, Hiroaki; Hashimoto, Shinichiro; Sugita, Yasumasa; Sakai, Shio; Takeda, Yusuke; Abe, Daijiro; Takagi, Toshiyuki; Nakaseko, Chiaki

    2012-10-01

    Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia, classified into primary and secondary types. Secondary CAD accompanies infection or malignant disease, most often lymphoma, whereas primary CAD frequently represents a lymphoproliferative bone marrow disorder characterized by clonal expansion of B cells. Here, I describe a case of lymphoplasmacytic lymphoma (LPL) developed 6 years after amelioration of primary CAD by rituximab monotherapy. A 54-year-old Japanese woman was diagnosed with primary CAD characterized by a small fraction of B lymphocytes and kappa laterality in the peripheral blood. M-protein was not detected by immuno-electrophoresis. The patient achieved remission following two courses of rituximab monotherapy. The level of IgM was specifically decreased, although levels of IgG and IgA were slightly increased. Six years after rituximab monotherapy, she developed LPL without CAD recurrence. Flow cytometry performed on bone marrow specimens revealed that lymphoma cells were positive for CD19 and CD20 with kappa laterality. The lymphoma may have transformed from clonal B lymphocytes at presentation of CAD. Rituximab monotherapy induced remission of CAD by specific decrease of IgM level, but did not eliminate the clonal B lymphocytes that may have progressed to LPL. This experience may provide clues toward the understanding of the pathophysiology of primary CAD with clonal lymphoproliferative disease of the bone marrow. PMID:22878940

  8. Use of rituximab as a treatment for systemic lupus erythematosus: retrospective review

    PubMed Central

    Machado, Roberta Ismael Lacerda; Scheinberg, Morton Aaron; de Queiroz, Maria Yvone Carlos Formiga; de Brito, Danielle Christinne Soares Egypto; Guimarães, Maria Fernanda Brandao de Resende; Giovelli, Raquel Altoé; Freire, Eutilia Andrade Medeiros

    2014-01-01

    ABSTRACT Objective: To report the experience in three Brazilian institutions with the use of rituximab in patients with different clinical forms of lupus erythematosus systemic in activity. Methods: The study consisted of a sample of 17 patients with LES, who were already being treated, but that at some stage of the disease showed refractory symptoms. The patients were subdivided into groups according to the clinical manifestation, and the responses for the use of rituximab were rated as complete, partial or no response. Data were collected through a spreadsheet, and used specific parameters for each group. The treatment was carried on by using therapeutic dose of 1g, and repeating the infusion within an interval of 15 days. Results: The clinical responses to rituximab of the group only hematological and of the group only osteoarticular were complete in all cases. In the renal group there was a clinical complete response, two partial and one absent. In the renal and hematological group complete response, there was one death and a missing response. The pulmonary group presented a complete response and two partial. Conclusion: The present study demonstrated that rituximab can bring benefits to patients with lupus erythematosus systemic, with good tolerability and mild side effects; it presented, however, variable response according to the system affected. PMID:24728244

  9. Rituximab is an effective and safe treatment of relapse in elderly patients with resistant warm AIHA.

    PubMed

    Laribi, Kamel; Bolle, Delphine; Ghnaya, Habib; Sandu, Andrea; Besançon, Anne; Denizon, Nathalie; Truong, Catherine; Pineau-Vincent, Fabienne; de Materre, Alix Baugier

    2016-04-01

    We evaluated the efficacy and safety of rituximab for the treatment of 23 elderly patients (median age 78 years) with warm autoimmune haemolytic anaemia (AIHA). The median follow-up was 31 months. Patients had received one to five previous treatments. Rituximab was administered by intravenous infusion at a dose of 375 mg/m(2) once weekly for 4 weeks. The OR rate was 86.9 % (CR = 39.1 %, PR = 47.8 %). Median OS was 87 months. The median OS of patients who reached CR could not be calculated, and that of patients with PR was 67 months. At last follow-up, eight of the 20 responding patients, including one patient in CR and seven in PR, had relapsed after a median of 6 months. Failure to achieve CR was a risk factor for relapse (p = 0.028). We did not identify any pretreatment characteristics predictive of response to rituximab. In conclusion, rituximab is an effective treatment for elderly patients with refractory warm AIHA. PMID:26858026

  10. Target-directed development and preclinical characterization of the proposed biosimilar rituximab GP2013

    PubMed Central

    Kronthaler, Ulrich; Koppenburg, Vera; Fink, Martin; Meyer, Ines; Papandrikopoulou, Anastassia; Hofmann, Matthias; Stangler, Thomas; Visser, Jan

    2014-01-01

    Biosimilar development involves a target-directed iterative process to ensure a similar product to the originator. Here we report the preclinical development of the proposed biosimilar rituximab (GP2013). Post-translational modifications and bioactivities of GP2013 versus originator rituximab were engineered and monitored to ensure similar pharmacological profiles. Antibody-dependent cellular cytotoxicity (ADCC) was used to illustrate how different glycosylation patterns and structure–function relationships were controlled during process development. Pharmacological comparability between GP2013 and originator rituximab were confirmed in preclinical studies using clinical scale drug product. Similar in vitro ADCC potency was demonstrated when compared in a dose–response manner against two lymphoma cell lines using freshly purified human natural killer (NK) cells. In vivo efficacy was demonstrated in two well characterized mouse xenograft models, testing at sensitive sub-therapeutic dose levels. Pharmacokinetics and pharmacodynamics (CD20 cell depletion) were likewise comparable in cynomolgus monkeys. This preclinical comparability exercise confirms that GP2013 and originator rituximab are pharmacologically similar. PMID:24024472

  11. Responsiveness to reduced dosage of rituximab in Chinese patients with neuromyelitis optica

    PubMed Central

    Yang, Chun-Sheng; Yang, Li; Li, Ting; Zhang, Da-Qi; Jin, Wei-Na; Li, Min-Shu; Su, Ning; Zhangning, Nannan; Liu, Qiang; Shao, Zong-Hong; Yu, Chunshui

    2013-01-01

    Objective: To determine the effect of a lower dose of rituximab in depleting B lymphocytes, maintaining low B-cell counts, and relapse in patients with neuromyelitis optica (NMO) and NMO spectrum disorders. Methods: We treated 5 Chinese patients with deteriorating NMO and NMO spectrum disorders with a 100-mg IV infusion of rituximab once a week for 3 consecutive weeks, followed by additional infusion of the same dosage depending on circulating B-cell repopulation. Results: This reduced dosage of rituximab was sufficient to deplete B cells and maintain low B-cell counts. None of the treated patients experienced relapse, and all patients exhibited stabilized or improved neurologic function during the 1-year follow-up period. MRI revealed the absence of new lesions, no enhancement in spinal cord and brain, a significant shrinkage of spinal cord segments, and a reduction/disappearance of previous brain lesions. Conclusion: A lower dosage of rituximab may be sufficient in depleting B cells, maintaining low B-cell counts, and preventing disease progression in Chinese patients with NMO. PMID:23884041

  12. Treatment of recurrent focal segmental glomerulosclerosis in pediatric kidney transplant recipients: effect of rituximab.

    PubMed

    Sethna, Christine; Benchimol, Corinne; Hotchkiss, Hilary; Frank, Rachel; Infante, Lulette; Vento, Suzanne; Trachtman, Howard

    2011-01-01

    Recurrence of focal segmental glomerulosclerosis (FSGS) after renal transplantation is a complication that often leads to graft loss. There is no consensus on the optimal treatment of recurrent FSGS. Rituximab, a monoclonal antibody to CD20, may be a useful treatment of this complication. Methods. We report four pediatric cases of recurrent FSGS treated with rituximab and plasmapheresis. Results. Four children (2M/2F), age 15.3 ± 2.6, with recurrent FSGS posttransplant were identified. Four doses of rituximab were administered 171 ± 180 days posttransplant and 114 ± 169 days after the start of plasmapheresis. Three children responded with complete remission, one of whom relapsed after four months. One child had a partial response with a decrease in proteinuria that was not sustained. No adverse side effects were reported during treatment or followup (mean 22.5 months). Conclusions. Rituximab is a safe and well-tolerated ancillary treatment for recurrent FSGS in pediatric patients in conjunction with plasmapheresis. PMID:21577271

  13. Treatment of Recurrent Focal Segmental Glomerulosclerosis in Pediatric Kidney Transplant Recipients: Effect of Rituximab

    PubMed Central

    Sethna, Christine; Benchimol, Corinne; Hotchkiss, Hilary; Frank, Rachel; Infante, Lulette; Vento, Suzanne; Trachtman, Howard

    2011-01-01

    Recurrence of focal segmental glomerulosclerosis (FSGS) after renal transplantation is a complication that often leads to graft loss. There is no consensus on the optimal treatment of recurrent FSGS. Rituximab, a monoclonal antibody to CD20, may be a useful treatment of this complication. Methods. We report four pediatric cases of recurrent FSGS treated with rituximab and plasmapheresis. Results. Four children (2M/2F), age 15.3 ± 2.6, with recurrent FSGS posttransplant were identified. Four doses of rituximab were administered 171 ± 180 days posttransplant and 114 ± 169 days after the start of plasmapheresis. Three children responded with complete remission, one of whom relapsed after four months. One child had a partial response with a decrease in proteinuria that was not sustained. No adverse side effects were reported during treatment or followup (mean 22.5 months). Conclusions. Rituximab is a safe and well-tolerated ancillary treatment for recurrent FSGS in pediatric patients in conjunction with plasmapheresis. PMID:21577271

  14. Treatment of myelitis in Behçet's disease with rituximab

    PubMed Central

    Messina, Maria Josè; Rodegher, Mariaemma; Scotti, Roberta; Martinelli, Vittorio

    2014-01-01

    Behçet's disease (BD) is a chronic inflammatory disorder that involves the parenchymal central nervous system (neuro-BD, NBD) approximately in 5–49% of patients, causing lesions rarely located in the spinal cord (SC). We report the first case of NBD-myelitis treated with intravenous rituximab. A 41-year-old man affected by BD presented with mild paraparesis with a miliary involvement and a ‘net-like’ gadolinium enhancement (Gde) of the SC. After a therapeutic attempt with pulsed cyclophosphamide and intravenous methylprednisolone, the clinical and neuroradiological course worsened. A progressive improvement was observed after rituximab administration associated with low doses of oral prednisone. No disease activity was detected and the patient reported no adverse event. After six rituximab cycles, cervical MRI was normal while thoracic MRI showed a slight T2–weighted hyperintensity of D4–D10 spinal tract without Gde. A combined use of rituximab and oral steroids resulted in a long-term suppression of NBD activity without any safety concern. PMID:24879733

  15. Rituximab in refractory myasthenia gravis: a prospective, open-label study with long-term follow-up.

    PubMed

    Anderson, Dustin; Phan, Cecile; Johnston, Wendy S; Siddiqi, Zaeem A

    2016-07-01

    We examined the clinical effectiveness of rituximab in fourteen patients with refractory myasthenia gravis (MG). Manual muscle testing (MMT) score was recorded at baseline and followed during the course of the study. Steroid dose, frequency of intravenous immunoglobulin (IVIG) infusions, and plasma exchange (PLEX) were also monitored throughout the duration of the study. All patients responded dramatically to rituximab, as measured by a change in MMT score, prednisone dose, or the frequency of IVIG infusions or PLEX. Rituximab appears safe and effective for the treatment of refractory MG. It should be considered as a therapeutic option in refractory patients. PMID:27386504

  16. Chimeric aptamers in cancer cell-targeted drug delivery

    PubMed Central

    Kanwar, Jagat R; Roy, Kislay; Kanwar, Rupinder K

    2011-01-01

    Aptamers are single-stranded structured oligonucleotides (DNA or RNA) that can bind to a wide range of targets ("apatopes") with high affinity and specificity. These nucleic acid ligands, generated from pools of random-sequence by an in vitro selection process referred to as systematic evolution of ligands by exponential enrichment (SELEX), have now been identified as excellent tools for chemical biology, therapeutic delivery, diagnosis, research, and monitoring therapy in real-time imaging. Today, aptamers represent an interesting class of modern Pharmaceuticals which with their low immunogenic potential mimic extend many of the properties of monoclonal antibodies in diagnostics, research, and therapeutics. More recently, chimeric aptamer approach employing many different possible types of chimerization strategies has generated more stable and efficient chimeric aptamers with aptamer-aptamer, aptamer-nonaptamer biomacromolecules (siRNAs, proteins) and aptamer-nanoparticle chimeras. These chimeric aptamers when conjugated with various biomacromolecules like locked nucleic acid (LNA) to potentiate their stability, biodistribution, and targeting efficiency, have facilitated the accurate targeting in preclinical trials. We developed LNA-aptamer (anti-nucleolin and EpCAM) complexes which were loaded in iron-saturated bovine lactofeerin (Fe-blf)-coated dopamine modified surface of superparamagnetic iron oxide (Fe3O4) nanoparticles (SPIONs). This complex was used to deliver the specific aptamers in tumor cells in a co-culture model of normal and cancer cells. This review focuses on the chimeric aptamers, currently in development that are likely to find future practical applications in concert with other therapeutic molecules and modalities. PMID:21955150

  17. Placebo-controlled trial of rituximab in IgM anti-myelin–associated glycoprotein neuropathy

    PubMed Central

    Viala, Karine; Nicolas, Guillaume; Créange, Alain; Vallat, Jean-Michel; Pouget, Jean; Clavelou, Pierre; Vial, Christophe; Steck, Andreas; Musset, Lucile; Marin, Benoit

    2013-01-01

    Objective: To determine whether rituximab 375 mg/m2 was efficacious in patients with immunoglobulin M (IgM) anti-myelin–associated glycoprotein antibody demyelinating neuropathy (IgM anti-MAG demyelinating neuropathy). Methods: Fifty-four patients with IgM anti-MAG demyelinating neuropathy were enrolled in this randomized, double-blind, placebo-controlled trial. The inclusion criteria were inflammatory neuropathy cause and treatment (INCAT) sensory score (ISS) ≥4 and visual analog pain scale >4 or ataxia score ≥2. The primary outcome was mean change in ISS at 12 months. Results: Twenty-six patients were randomized to a group receiving 4 weekly infusions of 375 mg/m2 rituximab, and 28 patients to placebo. Intention-to-treat analysis, with imputation of missing ISS values by the last observation carried forward method, showed a lack of mean change in ISS at 12 months, 1.0 ± 2.7 in the rituximab group, and 1.0 ± 2.8 in the placebo group. However, changes were observed, in per protocol analysis at 12 months, for the number of patients with an improvement of at least 2 points in the INCAT disability scale (p = 0.027), the self-evaluation scale (p = 0.016), and 2 subscores of the Short Form–36 questionnaire. Conclusions: Although primary outcome measures provide no evidence to support the use of rituximab in IgM anti-MAG demyelinating neuropathy, there were improvements in several secondary outcomes in per protocol analysis. Level of evidence: This study provides Class I evidence that rituximab is ineffective in improving ISS in patients with IgM anti-MAG demyelinating neuropathy. PMID:23667063

  18. Rapid depletion of B lymphocytes by ultra-low-dose rituximab delivered intrathecally

    PubMed Central

    Bergman, Joakim; Dring, Ann; Vågberg, Mattias; Birgander, Richard; Lindqvist, Thomas; Gilthorpe, Jonathan; Bergenheim, Tommy

    2015-01-01

    Objective: We are conducting an open-label phase 1b study on the efficacy of intrathecal (IT) administration of rituximab, provided via an Ommaya reservoir, for the treatment of progressive multiple sclerosis (PMS). The objective of this initial study was to monitor B lymphocytes in peripheral blood (PB) and CSF from the first 10 patients 1 year posttreatment. Methods: Dose titration was performed with daily escalation from 1 mg to 25 mg IT rituximab (n = 3). Lymphocyte subpopulations were monitored daily during dose escalation in PB by flow cytometry and subsequently every 3 months for 1 year, after a total dose of 3 × 25 mg. PB B-lymphocyte subpopulations for the remaining patients (n = 7) were monitored at regular intervals. CSF lymphocyte subpopulations for all patients were monitored by flow cytometry every 2–3 months. Results: The PB B-lymphocyte count dropped rapidly after the first 2 injections (total dose of 3.5 mg IT rituximab) to undetectable levels. Three 25-mg doses given once per week depleted peripheral B lymphocytes entirely for the following 3–6 month period. Conclusions: Monoclonal antibodies seem to rapidly redistribute to the peripheral compartment following IT injection. Ultra-low doses of rituximab given IT are sufficient to cause complete depletion of peripheral B lymphocytes, indicating that low-dose IT treatment has the potential to be effective in both the CNS and systemic compartments. Classification of evidence: This study provides Class IV evidence that for patients with PMS, rituximab provided via an Ommaya reservoir depletes peripheral blood B lymphocytes. PMID:25745637

  19. A New Kid on the Block: IL-10+ Regulatory B Cells and a Possible Role In Psoriasis

    PubMed Central

    Darabi, Kamruz; Jaiswal, Rohit; Hostetler, Sarah G.; Bechtel, Mark A.; Zirwas, Matthew J.; Witman, Patricia

    2009-01-01

    The pivotal role of T cells in the etiology of psoriasis has been elucidated; however, the mechanisms that regulate these T cells are unclear. Recently, it has been shown that an IL-10 producing B cell population may downregulate T cell function and it has been hypothesized that depletion of this B cell population may lead to exacerbation of T-cell mediated autoimmune disease. We present the case of an adolescent male with autoimmune lymphoproliferative syndrome (ALPS) being treated with the anti-CD20 chimeric monoclonal antibody rituximab in addition to intravenous immune globulin (IVIG) for immune thrombocytopenia (ITP) who developed a psoriasiform rash on his hands following mechanical trauma with concomitant severely decreased B cell count. We propose that depletion of the patient's B cells due to rituximab treatment may have led to abrogation of IL-10+ B-cell regulation of T cells. The development of a psoriasiform rash in this predisposed individual may have been triggered by mechanical trauma to his hands (koebnerization). In addition, we believe the patient's rash may have been tempered by concomitant treatment with IVIG, which has been used as treatment in cases of psoriasis. We discuss the immunologic mechanism of psoriasis and the role that a recently described IL-10+ B cell may play in preventing the pathologic process. Further studies are needed to more clearly elucidate this process. PMID:23055903

  20. Novel immunotherapies in lymphoid malignancies.

    PubMed

    Batlevi, Connie Lee; Matsuki, Eri; Brentjens, Renier J; Younes, Anas

    2016-01-01

    The success of the anti-CD20 monoclonal antibody rituximab in the treatment of lymphoid malignancies provided proof-of-principle for exploiting the immune system therapeutically. Since the FDA approval of rituximab in 1997, several novel strategies that harness the ability of T cells to target cancer cells have emerged. Reflecting on the promising clinical efficacy of these novel immunotherapy approaches, the FDA has recently granted 'breakthrough' designation to three novel treatments with distinct mechanisms. First, chimeric antigen receptor (CAR)-T-cell therapy is promising for the treatment of adult and paediatric relapsed and/or refractory acute lymphoblastic leukaemia (ALL). Second, blinatumomab, a bispecific T-cell engager (BiTE(®)) antibody, is now approved for the treatment of adults with Philadelphia-chromosome-negative relapsed and/or refractory B-precursor ALL. Finally, the monoclonal antibody nivolumab, which targets the PD-1 immune-checkpoint receptor with high affinity, is used for the treatment of Hodgkin lymphoma following treatment failure with autologous-stem-cell transplantation and brentuximab vedotin. Herein, we review the background and development of these three distinct immunotherapy platforms, address the scientific advances in understanding the mechanism of action of each therapy, and assess the current clinical knowledge of their efficacy and safety. We also discuss future strategies to improve these immunotherapies through enhanced engineering, biomarker selection, and mechanism-based combination regimens. PMID:26525683

  1. Novel immunotherapies in lymphoid malignancies

    PubMed Central

    Batlevi, Connie Lee; Matsuki, Eri; Brentjens, Renier J.; Younes, Anas

    2016-01-01

    The success of the anti-CD20 monoclonal antibody rituximab in the treatment of lymphoid malignancies provided proof-of-principle for exploiting the immune system therapeutically. Since the FDA approval of rituximab in 1997, several novel strategies that harness the ability of T cells to target cancer cells have emerged. Reflecting on the promising clinical efficacy of these novel immunotherapy approaches, the FDA has recently granted ‘breakthrough’ designation to three novel treatments with distinct mechanisms. First, chimeric antigen receptor (CAR)-T-cell therapy is promising for the treatment of adult and paediatric relapsed and/or refractory acute lymphoblastic leukaemia (ALL). Second, blinatumomab, a bispecific T-cell engager (BiTE®) antibody, is now approved for the treatment of adults with Philadelphia-chromosome-negative relapsed and/or refractory B-precursor ALL. Finally, the monoclonal antibody nivolumab, which targets the PD-1 immune-checkpoint receptor with high affinity, is used for the treatment of Hodgkin lymphoma following treatment failure with autologous-stem-cell transplantation and brentuximab vedotin. Herein, we review the background and development of these three distinct immunotherapy platforms, address the scientific advances in understanding the mechanism of action of each therapy, and assess the current clinical knowledge of their efficacy and safety. We also discuss future strategies to improve these immunotherapies through enhanced engineering, biomarker selection, and mechanism-based combination regimens. PMID:26525683

  2. Phase I study of radioimmunotherapy with an anti-CD20 murine radioimmunoconjugate ((90)Y-ibritumomab tiuxetan) in relapsed or refractory indolent B-cell lymphoma.

    PubMed

    Watanabe, Takashi; Terui, Shoji; Itoh, Kuniaki; Terauchi, Takashi; Igarashi, Tadahiko; Usubuchi, Noriko; Nakata, Masanobu; Nawano, Shigeru; Sekiguchi, Naohiro; Kusumoto, Shigeru; Tanimoto, Kazuki; Kobayashi, Yukio; Endo, Keigo; Seriu, Taku; Hayashi, Masaki; Tobinai, Kensei

    2005-12-01

    We conducted a phase I study to evaluate the safety and efficacy of radioimmunotherapy with yttrium-90-ibritumomab tiuxetan (Y2B8) in Japanese patients with relapsed or refractory indolent B-cell lymphoma. Indium-111-labeled ibritumomab tiuxetan (In2B8; 3.5 or 5 mCi [129.5 or 185 MBq]) was administered on day 1, followed by serial gamma-camera imaging to investigate the distribution of In2B8 in the whole body of patients and to judge the feasibility of Y2B8 administration. Y2B8 with a dose of 0.3 mCi/kg (11.1 MBq/kg) or 0.4 mCi/kg (14.8 MBq/kg) was administered on day 8. Grade 4 neutropenia and grade 3 thrombocytopenia were observed in three of nine of the patients evaluated for safety. Critical toxicities (prolonged thrombocytopenia or severe non-hematological toxicities) were observed in two of six patients in the 0.4 mCi/kg (14.8 MBq/kg) dose group but were not seen in any of the three patients in the 0.3 mCi/kg (11.1 MBq/kg) dose group. The non-hematological toxicities of the nine patients were of grade 2 or less, except in two patients who had been heavily treated previously. They experienced critical toxicities such as infection, diarrhea, hyponatremia and prolonged thrombocytopenia, as well as other frequent grade 2 non-hematological toxicities. Although the pharmacokinetic profiles were similar to those in the US study, one of the two patients was clarified retrospectively as showing abnormal biodistribution of In2B8 in the bone marrow, as judged by an independent third party panel of radiologists. Five of the 10 participants achieved complete responses or unconfirmed complete responses and two partial responses. In conclusion, the recommended dose of Y2B8 for the subsequent phase II study for Japanese patients is 0.4 mCi/kg (14.8 MBq/kg). This dose of radioimmunotherapy was feasible when patients with altered biodistribution of In2B8 were excluded, and it was highly effective. (Cancer Sci 2005; 96: 903-910). PMID:16367911

  3. Safety of Repeated Open-Label Treatment Courses of Intravenous Ofatumumab, a Human Anti-CD20 Monoclonal Antibody, in Rheumatoid Arthritis: Results from Three Clinical Trials

    PubMed Central

    Østergaard, Mikkel; Taylor, Peter C.; van Vollenhoven, Ronald F.; Chu, Myron; Mallett, Stephen; Perry, Hayley; Kurrasch, Regina

    2016-01-01

    Objectives To investigate the safety of ofatumumab retreatment in rheumatoid arthritis. Methods Patients with active rheumatoid arthritis participating in two phase III trials (OFA110635 and OFA110634) and a phase II extension trial (OFA111752) received individualised open-label ofatumumab retreatment (700 mg X 2 intravenous infusions two weeks apart) ≥24 weeks following the first course and ≥16 weeks following further courses. Retreatment required evidence of clinical response followed by disease relapse. These studies were prematurely terminated by the sponsor to refocus development on subcutaneous delivery. Due to differences in study designs and populations, data are summarised separately for each study. Results 483 patients (243, 148 and 92 in OFA110635, OFA110634 and OFA111752 respectively) received up to 7 treatment courses of intravenous ofatumumab; cumulative duration of exposure was 463, 182 and 175 patient-years, respectively. Mean time between courses was 17–47 weeks. Ofatumumab induced a profound depletion of peripheral B-lymphocytes. Retreated patients derived benefit based on improvement in DAS28. Adverse events were reported for 93% (226/243), 91% (134/148) and 76% (70/92), serious adverse events for 18% (44/243), 20% (30/148) and 12% (11/92) and serious infections for 3% (8/243), 5% (7/148) and 1% (1/92) of patients in OFA110635, OFA110634 and OFA111752, respectively. The most common adverse events were infusion-related reactions during the first infusion of the first course (48–79%); serious infusion-related reactions were rare (<1% [1/243], 5% [8/148], and 1% [1/92] of patients). Two deaths occurred (fulminant hepatitis B virus infection and interstitial lung disease). Conclusions Ofatumumab was generally well tolerated with no evidence of increased safety risks with multiple retreatments. Serious infections were uncommon and did not increase over time. Trial Registration ClinicalTrials.gov 110635 ClinicalTrials.gov 110634 ClinicalTrials.gov 111752 PMID:27336685

  4. Anti-CD20 Radioimmunotherapy Before Chemotherapy and Stem Cell Transplant in Treating Patients With High-Risk B-Cell Malignancies

    ClinicalTrials.gov

    2016-06-13

    Adult Burkitt Lymphoma; Adult Diffuse Large B-Cell Lymphoma; CD20-Positive Neoplastic Cells Present; Indolent Adult Non-Hodgkin Lymphoma; Mantle Cell Lymphoma; Recurrent B-Cell Non-Hodgkin Lymphoma; Refractory Mature B-Cell Non-Hodgkin Lymphoma

  5. High-Dose 131I-Tositumomab (Anti-CD20) Radioimmunotherapy for Non-Hodgkin's Lymphoma: Adjusting Radiation Absorbed Dose to Actual Organ Volumes

    SciTech Connect

    Rajendran, Joseph G.; Fisher, Darrell R.; Gopal, A K.; Durack, L. D.; Press, O. W.; Eary, Janet F.

    2004-06-01

    Radioimmunotherapy (RIT) using 131I-tositumomab has been used successfully to treat relapsed or refractory B-cell non-Hodgin's lymphoma (NHL). Our approach to treatment planning has been to determine limits on radiation absorbed close to critical nonhematopoietic organs. This study demonstrates the feasibility of using CT to adjust for actual organ volumes in calculating organ-specific absorbed dose estimates. Methods: Records of 84 patients who underwent biodistribution studies after a trace-labeled infusion of 131I-tositumomab for RIT (January 1990 and April 2003) were reviewed. Serial planar -camera images and whole-body Nal probe counts were obtained to estimate 131I-antibody source-organ residence times as recommended by the MIRD Committee. The source-organ residence times for standard man or woman were adjusted by the ratio of the MIRD phantom organ mass to the CT-derived organ mass. Results: The mean radiation absorbed doses (in mGy/MBq) for our data using the MIRD model were lungs= 1.67; liver= 1.03; kidneys= 1.08; spleen= 2.67; and whole body= 0.3; and for CT volume-adjusted organ volumes (in mGy/MBq) were lungs= 1.30; liver= 0.92; kidneys= 0.76; spleen= 1.40; and whole body= 0.22. We determined the following correlation coefficients between the 2 methods for the various organs; lungs, 0.49; (P= 0.0001); liver, 0.64 (P= 0.004); kidneys, 0.45 (P= 0.0001), for the residence times. For therapy, patients received mean 131I administered activities of 19.2 GBq (520 mCi) after adjustment for CT-derived organ mass compared with 16.0 GBq (433 mCi) that would otherwise have been given had therapy been based only using standard MIRD organ volumes--a statistically significant difference (P= 0.0001). Conclusion: We observed large variations in organ masses among our patients. Our treatments were planned to deliver the maximally tolerated radiation dose to the dose-limiting normal organ. This work provides a simplified method for calculating patient-specific radiation doses by adjusting for the actual organ mass and shows the value of this approach in treatment planning for RIT.

  6. Barriers to the Access and Use of Rituximab in Patients with Non-Hodgkin's Lymphoma and Chronic Lymphocytic Leukemia: A Physician Survey.

    PubMed

    Baer Ii, William H; Maini, Archana; Jacobs, Ira

    2014-01-01

    Biologics such as rituximab are an important component of oncology treatment strategies, although access to such therapies is challenging in countries with limited resources. This study examined access to rituximab and identified potential barriers to its use in the United States, Mexico, Turkey, Russia, and Brazil. The study also examined whether availability of a biosimilar to rituximab would improve access to, and use of, rituximab. Overall, 450 hematologists and oncologists completed a survey examining their use of rituximab in patients with non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Less than 40% of physicians considered rituximab as easy to access from a cost perspective. Furthermore, many physicians chose not to treat, were unable to treat, or had to modify treatment with rituximab despite guidelines recommending its use in NHL and CLL patients. Insurance coverage, reimbursement, and cost to patient were commonly reported as barriers to the use of rituximab. Across all markets, over half of physicians reported that they would increase use of rituximab if a biosimilar was available. We conclude that rituximab use would increase across all therapy types and markets if a biosimilar was available, although a biosimilar would have the greatest impact in Brazil, Mexico, and Russia. PMID:24810947

  7. Dose-Adjusted EPOCH-Rituximab Combined With Fludarabine Provides an Effective Bridge to Reduced-Intensity Allogeneic Hematopoietic Stem-Cell Transplantation in Patients With Lymphoid Malignancies

    PubMed Central

    Salit, Rachel B.; Fowler, Daniel H.; Wilson, Wyndham H.; Dean, Robert M.; Pavletic, Steven Z.; Dunleavy, Kieron; Hakim, Frances; Fry, Terry J.; Steinberg, Seth M.; Hughes, Thomas E.; Odom, Jeanne; Bryant, Kelly; Gress, Ronald E.; Bishop, Michael R.

    2012-01-01

    Purpose There is currently no standard chemotherapy regimen for patients with lymphoid malignancies being considered for reduced-intensity conditioning allogeneic hematopoietic stem-cell transplantation (RIC-alloHSCT). The ideal regimen would provide disease control and result in lymphocyte depletion to facilitate engraftment. To this end, we developed a novel regimen by adding fludarabine to dose-adjusted continuous-infusion etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus with or without rituximab (DA-EPOCH-F/R). Patients and Methods One hundred forty-seven patients with lymphoid malignancy (median age, 50 years) who had heavily pretreated (median prior regimens, three) and chemo-refractory (47%) disease were treated with DA-EPOCH-F/R before RIC-alloHSCT. Patients received one to three consecutive cycles until achieving lymphocyte depletion (CD4+ count < 200/μL) or progressive disease. Results Overall response rate was 41%; 39% of patients had stable disease. Toxicity included grade 4 neutropenia in 65% and thrombocytopenia in 25% of patients. DA-EPOCH-F/R resulted in lymphocyte depletion (P < .001), which was inversely associated with serum interleukin (IL) 7 and IL-15 levels. Of 147 patients, 143 patients proceeded to RIC-alloHSCT. Patients with lower CD3+ (P < .001), CD4+ (P < .001), and CD8+ (P < .001) T-cell counts after DA-EPOCH-F/R were more likely to achieve full donor lymphoid chimerism by day +14 after transplant. Relative to nonresponders to DA-EPOCH-F/R, patients with complete and partial response had increased event-free survival (77.4 v 4.8 months; P < .001) and overall survival (98.5 v 16.2 months; P < .001). Conclusion DA-EPOCH-F/R safely provides tumor cytoreduction and lymphocyte depletion, thereby offering a bridge to RIC-alloHSCT in patients with aggressive lymphoid malignancies. PMID:22312100

  8. Obinutuzumab in hematologic malignancies: lessons learned to date.

    PubMed

    Illidge, Tim; Klein, Christian; Sehn, Laurie H; Davies, Andrew; Salles, Gilles; Cartron, Guillaume

    2015-11-01

    The routine use of anti-CD20 monoclonal antibodies (mAbs) has improved patient outcomes in CD20-positive non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Despite the clinical success achieved with rituximab, relapses are still common with further improvements in anti-CD20 mAb efficacy required. Many novel anti-CD20 antibodies are in development, but obinutuzumab is currently the only type II glycoengineered anti-CD20 mAb in clinical testing. Obinutuzumab has increased antibody-dependent cell-mediated cytotoxicity, reduced complement-dependent cytotoxicity and enhanced direct non-apoptotic cell death. In preclinical models, obinutuzumab induced superior tumor remission compared with rituximab at the equivalent dose levels, and was active in rituximab-refractory tumors. Obinutuzumab exhibits encouraging efficacy as monotherapy in NHL, and combined with chemotherapy in relapsed/refractory NHL and treatment-naïve symptomatic CLL. In a recent randomized, phase III trial in patients with untreated comorbid CLL, overall response rate was significantly greater (78% vs. 65%, P<0.0001) and median progression-free survival was significantly prolonged (26.7 vs. 15.2months, P<0.0001) for obinutuzumab plus chlorambucil vs. rituximab plus chlorambucil. Obinutuzumab is a type II anti-CD20 antibody that utilizes distinct mechanisms of action relative to type I antibodies like rituximab and has led to significant clinical improvement over rituximab in a phase III trial in CLL. Further trials are ongoing to determine whether such improvements in outcome will be seen in CD20-positive B-cell malignancies. PMID:26190254

  9. Safety and efficacy of rituximab treatment for vasculitis in hepatitis B virus-associated type II cryoglobulinemia: a case report

    PubMed Central

    2012-01-01

    Introduction Systemic B-cell depletion and clinical remission of the systemic effects of cryoglobulins have already been achieved using rituximab in hepatitis C virus-positive immunocompetent patients. Conversely, to the best of our knowledge there are no reports in the literature regarding the use of rituximab in hepatitis B virus-associated cryoglobulinemia. Case presentation We report here the case of a 60-year-old Caucasian man who presented with hepatitis B virus-associated type II cryoglobulinemia with severe multisystem disease, including membranoproliferative glomerulonephritis with acute renal failure. The vasculitis was refractory to conventional and antiviral therapy but rituximab use led to a fall in cryoglobulin levels and disease control. The B-cell depletion was safe and efficient to induce a complete remission of the disease. Conclusion Our case highlights the benefit and the efficacy of rituximab in association with antiviral therapy in small vessel vasculitis related to hepatitis B virus-associated mixed cryoglobulinemia. PMID:22284897

  10. Rituximab and abatacept but not tocilizumab impair antibody response to pneumococcal conjugate vaccine in patients with rheumatoid arthritis

    PubMed Central

    2013-01-01

    Introduction The objective of the study was to investigate the impact of newer biologic treatments including rituximab, abatacept and tocilizumab on antibody response following pneumococcal vaccination using a 7-valent conjugate vaccine in patients with established rheumatoid arthritis (RA). Methods Patients with RA receiving rituximab, abatacept or tocilizumab as monotherapy or combined with methotrexate (MTX) participated in the study. Specific IgG antibodies against 23F and 6B serotypes were measured at vaccination and 4 to 6 weeks after vaccination using standardised ELISA. Geometric mean antibody levels (GML) were calculated. Antibody response (AR) was defined as the ratio between post- and pre-vaccination antibody levels and a positive antibody response (posAR) was AR ≥2. Results In total, 88 patients were enrolled in the study. Of 55 patients treated with rituximab, 26 (46%) were on concomitant MTX. Of patients receiving abatacept (n = 17) and tocilizumab (n = 16) biologic treatment was given in combination with MTX in 13 (76%) and 9 (56%) patients, respectively. Patients treated with rituximab had significantly lower AR compared to those on tocilizumab, as well as compared to previously reported RA patients on MTX and controls (spondylarthropathy patients treated with NSAIDs and/or analgesics). In total, 10.3% of patients on rituximab monotherapy and no patient on rituximab + MTX had posAR for both serotypes. For abatacept and tocilizumab the corresponding figures were 17.6% and 50%. Conclusion In this cohort of patients with established RA, treatment with rituximab and abatacept was associated with diminished antibody response but this was most pronounced for rituximab. Pneumococcal conjugate vaccine administrated during ongoing tocilizumab treatment seems to be associated with sufficient antibody response. Pneumococcal vaccination should preferably be encouraged before initiation of rituximab or abatacept treatment. Trial registration NCT

  11. Rituximab off label use for difficult-to-treat auto-immune diseases: reappraisal of benefits and risks.

    PubMed

    Sailler, Laurent

    2008-02-01

    Rituximab is increasingly used off label for difficult-to-treat auto-immune diseases. We reviewed the main case series or clinical studies to identify the best indications of rituximab and the situations at substantial risks for adverse events. Refractory immune thrombocytopenic purpura was the main indication. However, the long term benefit-to-risk ratio of rituximab treatment before or after splenectomy is unknown. A single 375 mg/m2 infusion may be as efficacious as the classical four infusions cycle. Rituximab is the best treatment for cold agglutinin disease. In warm agglutinin auto-immune anaemia, its efficacy has essentially been reported in chronic lymphocytic leukemia (CLL) patients and in children. In CLL patients, lethal adverse events occurred in patients also receiving cyclophosphamide. Rituximab seems to have an interesting benefit-to-risk ratio in Wegener granulomatosis (excepted in granulomatous lesions), HCV-associated symptomatic cryoglobulinemia in patients unresponsive to anti-viral therapy, pemphigus and thrombotic thrombocytopenic purpura. Efficacy and safety data in lupus are difficult to interpret. Serum sickness disease is not exceptional in immune thrombocytopenic purpura (ITP), lupus and sicca syndrome patients. A substantial infectious risk has been reported in pemphigus patients and in post-renal transplant cryoglobulinemia. Double-blind randomised controlled trials and phase IV studies are mandatory in most clinical settings to confirm the overall favourable perception of rituximab benefit to risk ratio. PMID:18270863

  12. A Randomized Controlled Trial of Rituximab Following Failure of Antiviral Therapy for Hepatitis C-Associated Cryoglobulinemic Vasculitis

    PubMed Central

    Sneller, Michael C.; Hu, Zonghui; Langford, Carol A.

    2011-01-01

    OBJECTIVES To report on the results of a randomized controlled trial of rituximab in hepatitis C virus (HCV)-associated mixed cryoglobulinemic vasculitis. METHODS We conducted an open-label single center randomized controlled trial of rituximab (375 mg/m2 per week for 4 weeks) compared to best available therapy for treatment of patients with HCV-associated cryoglobulinemic vasculitis in whom antiviral therapy failed to induce remission. The primary endpoint was remission at 6 months from study entry. RESULTS A total of 24 patients were enrolled. Baseline disease activity and organ involvement were similar in the two groups. Ten patients in the rituximab group (83%) were in remission at study month 6, compared with 1 patient in the control group (8%), a result that met criterion for stopping the study (P<0.001). The median duration of remission for rituximab-treated patients reaching the primary endpoint was 7 months. No adverse effect of rituximab on HCV plasma viremia or hepatic transaminase levels was observed. CONCLUSIONS Therapy with rituximab was well tolerated and effective treatment for patients with HCV-associated cryoglobulinemic vasculitis in whom antiviral therapy fails to induce remission. PMID:22147444

  13. Imaging and measuring the rituximab-induced changes of mechanical properties in B-lymphoma cells using atomic force microscopy

    SciTech Connect

    Li, Mi; Liu, Lianqing; Xi, Ning; Wang, Yuechao; Dong, Zaili; Tabata, Osamu; Xiao, Xiubin; Zhang, Weijing

    2011-01-14

    Research highlights: {yields} Single B-lymphoma living cells were imaged by AFM with the assistance of microfabricated pillars. {yields} The apoptosis of B-lymphoma cells triggered by rituximab without cross-linking was observed by AO/EB double fluorescent staining. {yields} The B-lymphoma cells became dramatically softer after adding rituximab. -- Abstract: The topography and mechanical properties of single B-lymphoma cells have been investigated by atomic force microscopy (AFM). With the assistance of microfabricated patterned pillars, the surface topography and ultrastructure of single living B-lymphoma cell were visualized by AFM. The apoptosis of B-lymphoma cells induced by rituximab alone was observed by acridine orange/ethidium bromide (AO/EB) double fluorescent staining. The rituximab-induced changes of mechanical properties in B-lymphoma cells were measured dynamically and the results showed that B-lymphoma cells became dramatically softer after incubation with rituximab. These results can improve our understanding of rituximab'effect and will facilitate the further investigation of the underlying mechanisms.

  14. Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naïve with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab's Efficacy in MTX iNadequate rEsponders (SERENE))

    PubMed Central

    Emery, P; Deodhar, A; Rigby, W F; Isaacs, J D; Combe, B; Racewicz, A J; Latinis, K; Abud-Mendoza, C; Szczepański, L J; Roschmann, R A; Chen, A; Armstrong, G K; Douglass, W; Tyrrell, H

    2010-01-01

    Objectives This phase III study evaluated the efficacy and safety of rituximab plus methotrexate (MTX) in patients with active rheumatoid arthritis (RA) who had an inadequate response to MTX and who were naïve to prior biological treatment. Methods Patients with active disease on stable MTX (10–25 mg/week) were randomised to rituximab 2×500 mg (n=168), rituximab 2×1000 mg (n=172), or placebo (n=172). From week 24, patients not in remission (Disease Activity Score (28 joints) ≥2.6) received a second course of rituximab; patients initially assigned to placebo switched to rituximab 2×500 mg. The primary end point was American College of Rheumatology 20 (ACR20) response at week 24. All patients were followed until week 48. Results At week 24, both doses of rituximab showed statistically superior efficacy (p<0.0001) to placebo (ACR20: 54%, 51% and 23%; rituximab (2×500 mg) + MTX, rituximab (2×1000 mg) + MTX and placebo + MTX, respectively). Secondary end points were also significantly improved for both rituximab groups compared with placebo. Further improvements in both rituximab arms were observed from week 24 to week 48. Rituximab + MTX was well tolerated, demonstrating comparable safety to placebo + MTX through to week 24, and between rituximab doses through to week 48. Conclusions Rituximab (at 2×500 mg and 2×1000 mg) plus MTX significantly improved clinical outcomes at week 24, which were further improved by week 48. No significant differences in either clinical or safety outcomes were apparent between the rituximab doses. PMID:20488885

  15. Chimeric NK-receptor–bearing T cells mediate antitumor immunotherapy

    PubMed Central

    Zhang, Tong; Lemoi, Bethany A.; Sentman, Charles L.

    2005-01-01

    NKG2D is an activating cell-surface receptor expressed on natural killer (NK) cells and some T-cell subsets. Its ligands are primarily expressed on tumor cells. The aim of this study was to determine whether chimeric NK-receptor—bearing T cells would directly kill tumor cells and lead to induction of host immunity against tumors. Chimeric NK receptors were produced by linking NKG2D or DNAX activating protein of 10 kDa (Dap10) to the cytoplasmic portion of the CD3ζ chain. Our results showed that chimeric (ch) NKG2D-bearing T cells responded to NKG2D-ligand–bearing tumor cells (RMA/Rae-1β, EG7) but not to wild-type tumor cells (RMA). This response was dependent upon ligand expression on the target cells but not on expression of major histocompatibility complex (MHC) molecules, and the response could be blocked by anti-NKG2D antibodies. These T cells produced large amounts of T-helper 1 (Th1) cytokines and proinflammatory chemokines and killed ligand–expressing tumor cells. Adoptive transfer of chNKG2D-bearing T cells inhibited RMA/Rae-1β tumor growth in vivo. Moreover, mice that had remained tumor-free were resistant to subsequent challenge with the wild-type RMA tumor cells, suggesting the generation of immunity against other tumor antigens. Taken together, our findings indicate that modification of T cells with chimeric NKG2D receptors represents a promising approach for immunotherapy against cancer. PMID:15890688

  16. Immunogenicity of candidate chimeric DNA vaccine against tuberculosis and leishmaniasis.

    PubMed

    Dey, Ayan; Kumar, Umesh; Sharma, Pawan; Singh, Sarman

    2009-08-13

    Mycobacterium tuberculosis and Leishmania donovani are important intracellular pathogens, especially in Indian context. In India and other South East Asian countries, both these infections are highly endemic and in about 20% cases co-infection of these pathogens is reported. For both these pathogens cell mediated immunity plays most important role. The available treatment of these infections is either prolonged or cumbersome or it is ineffective in controlling the outbreaks and spread. Therefore, potentiation of a common host defense mechanism can be used to prevent both the infections simultaneously. In this study we have developed a novel chimeric DNA vaccine candidate comprising the esat-6 gene of M. tuberculosis and kinesin motor domain gene of L. donovani. After developing this novel chimera, its immunogenicity was studied in mouse model. The immune response was compared with individual constructs of esat-6 and kinesin motor domain. The results showed that immunization with chimeric DNA vaccine construct resulted in stronger IFN-gamma and IL-2 response against kinesin (3012+/-102 and 367.5+/-8.92pg/ml) and ESAT-6 (1334+/-46.5 and 245.1+/-7.72pg/ml) in comparison to the individual vaccine constructs. The reciprocal immune response (IFN-gamma and IL-2) against individual construct was lower (kinesin motor domain: 1788+/-36.48 and 341.8+/-9.801pg/ml and ESAT-6: 867.0+/-47.23 and 170.8+/-4.578pg/ml, respectively). The results also suggest that using the chimeric construct both proteins yielded a reciprocal adjuvant affect over each other as the IFN-gamma production against chimera vaccination is statistically significant (p<0.0001) than individual construct vaccination. From this pilot study we could envisage that the chimeric DNA vaccine construct may offer an attractive strategy in controlling co-infection of leishmaniasis and tuberculosis and have important implication in future vaccine design. PMID:19559111

  17. Design of chimeric antigen receptors with integrated controllable transient functions.

    PubMed

    Juillerat, Alexandre; Marechal, Alan; Filhol, Jean-Marie; Valton, Julien; Duclert, Aymeric; Poirot, Laurent; Duchateau, Philippe

    2016-01-01

    The ability to control T cells engineered to permanently express chimeric antigen receptors (CARs) is a key feature to improve safety. Here, we describe the development of a new CAR architecture with an integrated switch-on system that permits to control the CAR T-cell function. This system offers the advantage of a transient CAR T-cell for safety while letting open the possibility of multiple cytotoxicity cycles using a small molecule drug. PMID:26750734

  18. Chimeric plumage coloration produced by ovarian transplantation in chickens.

    PubMed

    Liu, J; Robertson, M C; Cheng, K M; Silversides, F G

    2013-04-01

    Ovaries from Rhode Island Red donors were transplanted orthotopically into White Leghorn recipients. At maturation, recipients were mated with Rhode Island Red roosters to test the origin of their ovaries, using plumage coloration as a marker. A chick with chimeric plumage coloration was produced, indicating mechanisms that produce follicles with both donor and recipient ovarian contents. This study suggests that ovarian transplantation could be useful for in vivo studies of cytological and molecular mechanisms involved in avian folliculogenesis. PMID:23472030

  19. A modular strategy for engineering orthogonal chimeric RNA transcription regulators

    PubMed Central

    Takahashi, Melissa K.; Lucks, Julius B.

    2013-01-01

    Antisense RNA transcription attenuators are a key component of the synthetic biology toolbox, with their ability to serve as building blocks for both signal integration logic circuits and transcriptional cascades. However, a central challenge to building more sophisticated RNA genetic circuitry is creating larger families of orthogonal attenuators that function independently of each other. Here, we overcome this challenge by developing a modular strategy to create chimeric fusions between the engineered transcriptional attenuator from plasmid pT181 and natural antisense RNA translational regulators. Using in vivo gene expression assays in Escherichia coli, we demonstrate our ability to create chimeric attenuators by fusing sequences from five different translational regulators. Mutagenesis of these functional attenuators allowed us to create a total of 11 new chimeric attenutaors. A comprehensive orthogonality test of these culminated in a 7 × 7 matrix of mutually orthogonal regulators. A comparison between all chimeras tested led to design principles that will facilitate further engineering of orthogonal RNA transcription regulators, and may help elucidate general principles of non-coding RNA regulation. We anticipate that our strategy will accelerate the development of even larger families of orthogonal RNA transcription regulators, and thus create breakthroughs in our ability to construct increasingly sophisticated RNA genetic circuitry. PMID:23761434

  20. AFM analysis of the multiple types of molecular interactions involved in rituximab lymphoma therapy on patient tumor cells and NK cells.

    PubMed

    Li, Mi; Xiao, Xiubin; Zhang, Weijing; Liu, Lianqing; Xi, Ning; Wang, Yuechao

    2014-08-01

    Rituximab is a monoclonal antibody drug approved for the treatment of patients with lymphomas. Rituximab's main killing mechanism is antibody-dependent cellular cytotoxicity (ADCC). During ADCC, rituximab's fragment antigen binding (Fab) region binds to the CD20 antigen on the tumor cell and its fragment crystallizable (Fc) region binds to the Fc receptor (FcR) on the natural killer (NK) cells. In this study, two types of molecular interactions (CD20-rituximab, FcR-rituximab) involved in ADCC were measured simultaneously on cells prepared from biopsy specimens of lymphoma patients by utilizing atomic force microscopy (AFM) with functionalized tips carrying rituximab. NK cells were detected by specific NKp46 fluorescent labeling and tumor cells were detected by specific ROR1 fluorescent labeling. Based on the fluorescence recognition, the binding affinity and distribution of FcRs on NK cells, and CD20 on tumor cells, were quantitatively measured and mapped. The binding affinity and distribution of FcRs (on NK cells) and CD20 (on tumor cells) were associated with rituximab clinical efficacy. The experimental results provide a new approach to simultaneously quantify the multiple types of molecular interactions involved in rituximab ADCC mechanism on patient biopsy cells, which is of potential clinical significance to predict rituximab efficacy for personalized medicine. PMID:25117605

  1. Ofatumumab is active in patients with fludarabine-refractory CLL irrespective of prior rituximab: results from the phase 2 international study

    PubMed Central

    Padmanabhan, Swaminathan; Chan, Geoffrey W.; Gupta, Ira V.; Lisby, Steen; Österborg, Anders

    2011-01-01

    Ofatumumab, the human CD20 monoclonal antibody that binds a distinct epitope from rituximab, has demonstrated clinical benefit as monotherapy for patients with chronic lymphocytic leukemia refractory to fludarabine and alemtuzumab (FA-ref) and patients refractory to fludarabine with bulky (> 5 cm) lymph nodes (BF-ref). To potentially gain insight into outcomes in patients previously treated with or refractory to rituximab, we performed an ad hoc retrospective analysis in the final 96 FA-ref and 111 BF-ref patients. There were 117 patients previously treated with rituximab (98 rituximab-refractory); 89 patients were rituximab-naive. For rituximab-treated, rituximab-refractory, and rituximab-naive patients, overall response rate was 43%, 44%, and 53%; median progression-free survival was 5.3, 5.5, and 5.6 months; and median overall survival was 15.5, 15.5, and 20.2 months. There were no significant differences in ofatumumab-related infusion reactions, or hematologic or infectious adverse events between subgroups. In summary, ofatumumab monotherapy was effective and well tolerated in patients with fludarabine-refractory chronic lymphocytic leukemia, including in patients with previous rituximab exposure. This trial was registered at www.clinicaltrials.gov as #NCT00349349. PMID:21856867

  2. Primary renal lymphoma: long-term results of two patients treated with a chemotherapy + rituximab protocol.

    PubMed

    Vázquez-Alonso, F; Puche-Sanz, I; Sánchez-Ramos, C; Flores-Martín, J; Vicente-Prados, J; Cózar-Olmo, J M

    2012-01-01

    Primary renal lymphoma (PRL) is a rare disease of which the etiology and pathogenesis remain controversial, and there is currently no standard treatment for it. We present the results of a long-term followup of two patients who were diagnosed with PRL and treated with cyclophosphamide, adriamycin, vincristine, prednisolone and rituximab (CHOP + R) regimen. Both patients reached a complete response, and there is no evidence of recurrence after 4.5- and 5-year followup periods. Based on our experience and other recently published studies, we recommend the combination of CHOP + rituximab as the elective treatment for this disease. To our knowledge, this is the longest followup period with a complete response that has been reported with this modality of treatment. PMID:22997596

  3. False Positive B-Cells Crossmatch after Prior Rituximab Exposure of the Kidney Donor

    PubMed Central

    Desoutter, Judith; Apithy, Marie-Joëlle; Bartczak, Ségolène; Guillaume, Nicolas

    2016-01-01

    Crossmatching is essential prior to kidney transplantation to confirm compatibility between the donor and the recipient, particularly to prevent acute antibody-mediated rejection. An unexpected positive crossmatch may be obtained in recipients with an autoimmune disease or preexisting antibodies not detected by single-antigen bead array due to complement interference or who have been previously treated by desensitization protocols such as rituximab, antithymocyte globulin, or intravenous immunoglobulins. We report donor and recipient investigations that revealed unexpected positive B-cells crossmatch, probably due to donor cells, as the donor had received rituximab therapy shortly before organ harvesting, in a context of severe idiopathic thrombocytopenic purpura. We consequently detected unexpected Class II IgG complement-dependent cytotoxicity for all sera tested. Other laboratory investigations failed to elucidate the reasons for this recipient-related positivity.

  4. B-cell targeted therapy with rituximab for thyroid eye disease: closer to the clinic.

    PubMed

    Shen, Sunny; Chan, Anita; Sfikakis, Petros P; Hsiu Ling, Andrea Low; Detorakis, Efstathios T; Boboridis, Kostas G; Mavrikakis, Ioannis

    2013-01-01

    The management of thyroid eye disease (TED) remains a therapeutic challenge. The current established therapies are unsatisfactory in one-third of the patients and have many limitations. Rituximab (RTX) is a CD20+ B-cell-depleting monoclonal antibody approved for the treatment of non-Hodgkin lymphomas, chronic lymphocytic leukemia, and rheumatoid arthritis. The early experience with RTX suggests that it is a promising alternative therapy for TED. Rituximab may compare favorably to the conventional glucocorticoid therapy and causes less collateral damage than retrobulbar orbital radiation and decompression surgery. In addition, the preliminary studies on RTX's proposed mechanism of action have revealed new insights into the pathogenic role of B-cells in TED. We summarize the current literature on the clinical application of RTX in TED and discuss its putative mechanisms of action. PMID:23253433

  5. Leuconostoc sp. Meningitis in a Patient Treated with Rituximab for Mantle Cell Lymphoma

    PubMed Central

    Holik, Hrvoje; Coha, Božena; Šiško, Marijan; Tomić-Paradžik, Maja

    2015-01-01

    We present a 64-year-old man who was treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemoimmunotherapy for mantle cell lymphoma and developed purulent meningitis, probably caused by Leuconostoc sp. The patient had severe hypogammaglobulinemia, which is a possible complication of rituximab therapy. To our knowledge and after reviewing the available medical literature, this is the first described case of purulent meningitis caused by Leuconostoc sp. in a patient with mantle cell lymphoma that appeared after treatment with the R-CHOP protocol. The diagnosis of purulent meningitis was based on clinical, laboratory and cytological cerebrospinal fluid findings, in addition to blood culture results in which we isolated Leuconostoc sp. The patient was treated with meropenem with full recovery. PMID:26376594

  6. Safety and clinical outcomes of rituximab therapy in patients with different autoimmune diseases: experience from a national registry (GRAID)

    PubMed Central

    2011-01-01

    Introduction Evidence from a number of open-label, uncontrolled studies has suggested that rituximab may benefit patients with autoimmune diseases who are refractory to standard-of-care. The objective of this study was to evaluate the safety and clinical outcomes of rituximab in several standard-of-care-refractory autoimmune diseases (within rheumatology, nephrology, dermatology and neurology) other than rheumatoid arthritis or non-Hodgkin's lymphoma in a real-life clinical setting. Methods Patients who received rituximab having shown an inadequate response to standard-of-care had their safety and clinical outcomes data retrospectively analysed as part of the German Registry of Autoimmune Diseases. The main outcome measures were safety and clinical response, as judged at the discretion of the investigators. Results A total of 370 patients (299 patient-years) with various autoimmune diseases (23.0% with systemic lupus erythematosus, 15.7% antineutrophil cytoplasmic antibody-associated granulomatous vasculitides, 15.1% multiple sclerosis and 10.0% pemphigus) from 42 centres received a mean dose of 2,440 mg of rituximab over a median (range) of 194 (180 to 1,407) days. The overall rate of serious infections was 5.3 per 100 patient-years during rituximab therapy. Opportunistic infections were infrequent across the whole study population, and mostly occurred in patients with systemic lupus erythematosus. There were 11 deaths (3.0% of patients) after rituximab treatment (mean 11.6 months after first infusion, range 0.8 to 31.3 months), with most of the deaths caused by infections. Overall (n = 293), 13.3% of patients showed no response, 45.1% showed a partial response and 41.6% showed a complete response. Responses were also reflected by reduced use of glucocorticoids and various immunosuppressives during rituximab therapy and follow-up compared with before rituximab. Rituximab generally had a positive effect on patient well-being (physician's visual analogue scale; mean

  7. Successful therapy with rituximab of refractory acute humoral renal transplant rejection: a case report.

    PubMed

    Celik, A; Saglam, F; Cavdar, C; Sifil, A; Atila, K; Sarioglu, S; Bora, S; Gulay, H; Camsari, T

    2008-01-01

    Acute humoral rejection (AHR) is generally less responsive to conventional anti-rejection treatment with consequent allograft losses. Therapeutic options include antilymphocyte antibody (ATG), intravenous immunglobulin (IVIG), plasmapheresis, or immunoadsorption with protein A together with intensification of immunsuppression with a tacrolimus/mycophenolate mofetil combination. This report describes a transplant recipient who responded to rituximab therapy as treatment for steroid-, ATG-, IVIG-, and plasmapheresis-resistant AHR. PMID:18261611

  8. Rituximab: how approval history is reflected by a corresponding patent filing strategy.

    PubMed

    Storz, Ulrich

    2014-01-01

    Because drug development is not a static process, a drug's market authorisation may change over time. In many cases, the number of indications for which a drug is approved increases. Because this facet of drug development also comes at significant costs, a corresponding patent filing strategy is required to protect these investments. The strategy as applied to rituximab, which is approved for a variety of indications, is discussed in this review. PMID:24866199

  9. High-dose methotrexate with or without rituximab in newly diagnosed primary CNS lymphoma

    PubMed Central

    Ambady, Prakash; Abdelaziz, Ahmed; Sarai, Guneet; Bonekamp, David; Blakeley, Jaishri; Grossman, Stuart A.; Ye, Xiaobu

    2014-01-01

    Objective: To evaluate the efficacy of rituximab (R) when added to high-dose methotrexate (HD-MTX) in patients with newly diagnosed immunocompetent primary CNS lymphomas (PCNSLs). Methods: Immunocompetent adults with newly diagnosed PCNSL treated at The Johns Hopkins Hospital between 1995 and 2012 were investigated. From 1995 to 2008, patients received HD-MTX monotherapy (8 g/m2 initially every 2 weeks and after complete response [CR] monthly to complete 12 months of therapy). From 2008 to 2012, patients received the same HD-MTX with rituximab (375 mg/m2) with each HD-MTX treatment. CR rates and median overall and progression-free survival were analyzed for each patient cohort in this single-institution, retrospective study. Results: A total of 81 patients were identified: 54 received HD-MTX (median age 66 years) while 27 received HD-MTX/R (median age 65 years). CR rates were 36% in the HD-MTX cohort and 73% in the HD-MTX/R cohort (p = 0.0145). Median progression-free survival was 4.5 months in the HD-MTX cohort and 26.7 months in the HD-MTX/R cohort (p = 0.003). Median overall survival was 16.3 months in the HD-MTX cohort and has not yet been reached in the HD-MTX/R cohort (p = 0.01). Conclusions: The addition of rituximab to HD-MTX appears to improve CR rates as well as overall and progression-free survival in patients with newly diagnosed PCNSL. Comparisons of long-term survival in the 2 cohorts await further maturation of the data. Classification of evidence: This study provides Class III evidence that in immunocompetent patients with PCNSL, HD-MTX plus rituximab compared with HD-MTX alone improves CR and overall survival rates. PMID:24928128

  10. Successful Management of Refractory Dialysis Independent Wegener's Granulomatosis with Combination of Therapeutic Plasma Exchange and Rituximab.

    PubMed

    Malhotra, Sheetal; Dhawan, Hari Krishan; Sharma, Ratti Ram; Marwaha, Neelam; Sharma, Aman

    2016-06-01

    Wegeners granulomatosis (WG) is an autoimmune, antineutrophil cytoplasmic antibody mediated necrotizing vasculitis involving renal, and upper and lower respiratory systems. Treatment relies on a combination of immunosuppressive drugs and tapering regimen of glucocorticoids. Therapeutic plasma exchange (TPE) has been recognized as a second line treatment. We report the successful use of TPE in combination with rituximab in achieving remission in a patient with WG (dialysis independent) not responding to conventional therapy. PMID:27408429

  11. Expression and purification of toxic anti-breast cancer p28-NRC chimeric protein

    PubMed Central

    Soleimani, Meysam; Mirmohammad-Sadeghi, Hamid; Sadeghi-Aliabadi, Hojjat; Jahanian-Najafabadi, Ali

    2016-01-01

    Background: Chimeric proteins consisting of a targeting moiety and a cytotoxic moiety are now under intense research focus for targeted therapy of cancer. Here, we report cloning, expression, and purification of such a targeted chimeric protein made up of p28 peptide as both targeting and anticancer moiety fused to NRC peptide as a cytotoxic moiety. However, since the antimicrobial activity of the NRC peptide would intervene expression of the chimeric protein in Escherichia coli, we evaluated the effects of two fusion tags, that is, thioredoxin (Trx) and 6x-His tags, and various expression conditions, on the expression of p28-NRC chimeric protein. Materials and Methods: In order to express the chimeric protein with only 6x-His tag, pET28 expression plasmid was used. Cloning in pET32 expression plasmid was performed to add both Trx and 6x-His tags to the chimeric protein. Expression of the chimeric protein with both plasmids was evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot analysis following optimization of expression conditions and host strains. Results: Expression of the chimeric protein in pET28a was performed. However, expression yield of the chimeric protein was low. Optimization of culture conditions and host strains led to reasonable expression yield of the toxic chimeric protein in pET32a vector. In cases of both plasmids, approximately 10 kDa deviation of the apparent molecular weight from the theoretical one was seen in SDS-PAGE of purified chimeric proteins. Conclusions: The study leads to proper expression and purification yield of p28-NRC chimeric protein with Trx tag following optimizing culture conditions and host strains. PMID:27169101

  12. Chimeric Proteins to Detect DNA Damage and Mismatches

    SciTech Connect

    McCutchen-Maloney, S; Malfatti, M; Robbins, K M

    2002-01-14

    The goal of this project was to develop chimeric proteins composed of a DNA mismatch or damage binding protein and a nuclease, as well as methods to detect DNA mismatches and damage. We accomplished this through protein engineering based on using polymerase chain reactions (PCRs) to create chimeras with novel functions for damage and mismatch detection. This project addressed fundamental questions relating to disease susceptibility and radiation-induced damage in cells. It also supported and enhanced LLNL's competency in the emerging field of proteomics. In nature, DNA is constantly being subjected to damaging agents such as exposure to ultraviolet (UV) radiation and various environmental and dietary carcinogens. If DNA damage is not repaired however, mutations in DNA result that can eventually manifest in cancer and other diseases. In addition to damage-induced DNA mutations, single nucleotide polymorphisms (SNPs), which are variations in the genetic sequence between individuals, may predispose some to disease. As a result of the Human Genome Project, the integrity of a person's DNA can now be monitored. Therefore, methods to detect DNA damage, mutations, and SNPs are useful not only in basic research but also in the health and biotechnology industries. Current methods of detection often use radioactive labeling and rely on expensive instrumentation that is not readily available in many research settings. Our methods to detect DNA damage and mismatches employ simple gel electrophoresis and flow cytometry, thereby alleviating the need for radioactive labeling and expensive equipment. In FY2001, we explored SNP detection by developing methods based on the ability of the chimeric proteins to detect mismatches. Using multiplex assays with flow cytometry and fluorescent beads to which the DNA substrates where attached, we showed that several of the chimeras possess greater affinity for damaged and mismatched DNA than for native DNA. This affinity was demonstrated in

  13. Brain Abscess following Rituximab Infusion in a Patient with Pemphigus Vulgaris

    PubMed Central

    Al-Harbi, Talal M.; Muammer, Shahad A.; Ellis, Ronald J.

    2015-01-01

    Patient: Female, 52 Final Diagnosis: Brain abscess Symptoms: Fever • headache • weakness, left sided Medication: Prednisolone • Azathioprine • Rituximab Clinical Procedure: Stereotactic brain biopsy and LP Specialty: Neurology Objective: Rare disease Background: Immunocompromised patients are at increased risk for developing meningitis or, rarely, brain abscess with opportunistic organisms like Listeria monocytogenes. Case Report: A 52 year-old Saudi Arabian woman who was diagnosed with pemphigus vulgaris and diabetes and had been on prednisolone and azathioprine for about 4 years. She presented with headache, low-grade fever, and left-sided weakness 2 weeks after receiving the second dose of rituximab infusion. Magnetic resonance imaging revealed an enhanced space-occupying lesion with multiple small cyst-like structures and vasogenic edema in the right temporoparietal area. Her blood culture was positive for Listeria monocytogenes, and a brain biopsy showed necrotic tissues with pus and inflammatory cells. She recovered after a 6-week course of antibiotics with ampicillin and gentamycin. Conclusions: Brain abscess due to Listeria monocytogenes is a risk that should be considered when adding rituximab to the regimen of a patient who is already Immunocompromised. PMID:25659437

  14. Clinical review: Serious adverse events associated with the use of rituximab - a critical care perspective

    PubMed Central

    2012-01-01

    The advent of biologic agents has provided a more specific and targeted approach to the treatment of various hematological malignancies and other autoimmune disorders. Such biologic agents have been relatively well tolerated with fewer adverse events reported as compared with many other chemotherapeutic agents. Rituximab is a monoclonal antibody to the B-cell marker CD20 and is a common biologic agent widely used for the treatment of B-cell lymphoma, lymphoproliferative disorders, and inflammatory conditions that are refractory to conventional treatment, including rheumatoid arthritis and some vasculitides. However, through randomized controlled trials and post-marketing surveillance, an increasing number of serious adverse events are being associated with the use of rituximab, often leading to or complicating an intensive care unit admission. The purpose of this review is to focus on the severe complications that are associated with the use of rituximab and that require critical care. Management and prevention strategies for the most common complications along with some examples of its uses within the critical care setting are also discussed. PMID:22967460

  15. Effects of hypertonic buffer composition on lymph node uptake and bioavailability of rituximab, after subcutaneous administration

    PubMed Central

    Fathallah, Anas M.; Turner, Michael R.; Balu-Iyer, Sathy V.

    2015-01-01

    Subcutaneous administration of biologics is highly desirable; however, incomplete bioavailability after sc administration remains a major challenge. In this work we investigated the effects of excipient dependent hyper-osmolarity on lymphatic uptake and plasma exposure of rituximab as a model protein. Using Swiss Webster (SW) mice as our animal model, we compared the effects of NaCl, mannitol and, O-Phospho-L-Serine (OPLS) on plasma concentration of rituximab over 5 days after sc administration. We observed an increase in plasma concentrations in animals administered rituximab in hypertonic buffer solutions, as compared to isotonic buffer. Bioavailability, as estimated by our pharmacokinetic model, increased from 29% in isotonic buffer to 54% in hypertonic buffer containing NaCl, to almost complete bioavailability in hypertonic buffers containing high dose OPLS or mannitol. This improvement in plasma exposure is due to improved lymphatic trafficking as evident from the increase in the fraction of dose trafficked through the lymph node in the presence of hypertonic buffers. The fraction of the dose trafficked through the lymphatic, as estimated by the model, increased from 0.05 % in isotonic buffer to 13% in hyper-tonic buffer containing NaCl to about 30% for hypertonic buffers containing high dose OPLS and mannitol. Our data suggests that hypertonic solutions may be a viable option to improve sc bioavailability. PMID:25377184

  16. Long-term outcomes to fludarabine and rituximab in Waldenström macroglobulinemia

    PubMed Central

    Branagan, Andrew R.; Ioakimidis, Leukothea; Soumerai, Jacob D.; Patterson, Christopher J.; Turnbull, Barry; Wasi, Parveen; Emmanouilides, Christos; Frankel, Stanley R.; Lister, Andrew; Morel, Pierre; Matous, Jeffrey; Gregory, Stephanie A.; Kimby, Eva

    2009-01-01

    We report the long-term outcome of a multicenter, prospective study examining fludarabine and rituximab in Waldenström macroglobulinemia (WM). WM patients with less than 2 prior therapies were eligible. Intended therapy consisted of 6 cycles (25 mg/m2 per day for 5 days) of fludarabine and 8 infusions (375 mg/m2 per week) of rituximab. A total of 43 patients were enrolled. Responses were: complete response (n = 2), very good partial response (n = 14), partial response (n = 21), and minor response (n = 4), for overall and major response rates of 95.3% and 86.0%, respectively. Median time to progression for all patients was 51.2 months and was longer for untreated patients (P = .017) and those achieving at least a very good partial response (P = .049). Grade 3 or higher toxicities included neutropenia (n = 27), thrombocytopenia (n = 7), and pneumonia (n = 6), including 2 patients who died of non–Pneumocystis carinii pneumonia. With a median follow-up of 40.3 months, we observed 3 cases of transformation to aggressive lymphoma and 3 cases of myelodysplastic syndrome/acute myeloid leukemia. The results of this study demonstrate that fludarabine and rituximab are highly active in WM, although short- and long-term toxicities need to be carefully weighed against other available treatment options. This study is registered at clinicaltrials.gov as NCT00020800. PMID:19015393

  17. Recurrence of light chain deposit disease after renal allograft transplantation: potential role of rituximab?

    PubMed

    Kuypers, Dirk R J; Lerut, Evelyne; Claes, Kathleen; Evenepoel, Pieter; Vanrenterghem, Yves

    2007-04-01

    Light chain deposit disease (LCDD) is a monoclonal plasma cell disorder characterized by tissue deposition of nonamyloid immunoglobulin light chains, predominantly kappa chains, causing renal insufficiency. LCDD reoccurs almost invariably after renal grafting, leading to early graft loss, usually within a time span of months to years. We describe a female patient with LCDD who lost her first living donor graft after 1 year due to extensive recurrence of kappa chain deposition. Rituximab was administered on the seventh day after her second transplantation with a graft from a deceased donor, in order to prevent early recurrence of LCDD. The 2-year protocol biopsy - similarly to the completely normal 1-year protocol biopsy - revealed persistent absence of light chain deposition on light microscopy but immunohistochemical staining and electron microscopy showed very mild recurrence of light chain deposits. A second 4-week course of rituximab was repeated because of these electron microscopic findings. Subsequently, free kappa light chain concentration decreased from 693 to 74 mg/l and remained low 4 months after completion of therapy. Rituximab could be considered for delaying early LCDD recurrence in patients in whom treatment of the underlying bone marrow disorder failed or is contraindicated, but maintenance therapy is apparently necessary to consolidate this response. PMID:17326779

  18. Prognostic model for mantle cell lymphoma in the rituximab era: a nationwide study in Japan.

    PubMed

    Chihara, Dai; Asano, Naoko; Ohmachi, Ken; Kinoshita, Tomohiro; Okamoto, Masataka; Maeda, Yoshinobu; Mizuno, Ishikazu; Matsue, Kosei; Uchida, Toshiki; Nagai, Hirokazu; Nishikori, Momoko; Nakamura, Shigeo; Ogura, Michinori; Suzuki, Ritsuro

    2015-09-01

    Mantle cell lymphoma (MCL) is essentially incurable with conventional chemotherapy. The MCL International Prognostic Index (MIPI) is a validated specific prognostic index, but was derived from patients with advanced-stage disease primarily in the pre-rituximab era. We analysed 501 MCL patients (median age, 67 years; range 22-90) treated with rituximab-containing chemotherapy, and evaluated the prognostic factors adjusted by the treatment. Five-year overall survival (OS) in the low, intermediate and high MIPI groups was 74%, 70% and 35%, respectively. Additional to MIPI risk factors, multivariate analysis revealed that low serum albumin and bone-marrow involvement were also significantly associated with a poor outcome. The revised-MIPI (R-MIPI) was constructed using six factors, namely age, performance status, white blood cell count, serum lactate dehydrogenase, bone-marrow involvement and serum albumin, which is divided into four prognostic groups. Five-year OS in low, low-intermediate (L-I), high-intermediate (H-I) and high R-MIPI groups was 92%, 75%, 61% and 19%, respectively. Hazard ratio for OS of L-I, H-I and high risk to low risk patients were 5·4, 8·3 and 33·0, respectively. R-MIPI, a new prognostic index with easy application to the general patient population, shows promise for identifying low- and high-risk MCL patients in the rituximab era. PMID:25953436

  19. New insight in the mechanism of action of rituximab: the interferon signature towards personalized medicine.

    PubMed

    Verweij, Cornelis L; Vosslamber, Saskia

    2011-09-01

    Rheumatoid arthritis (RA) is the most common chronic inflammatory disorder of the musculoskeletal system that may cause permanent joint damage. The disease has a major impact on the quality of life of affected individuals, costs for the health care system, and society. Currently, no curative treatment is available, and patients are subjected to a prolonged course of treatment. Due to their role in the pathogenesis of RA, B cells have become an attractive target for therapy. Rituximab (Mabthera®/Rituxan®) is a therapeutic monoclonal antibody against CD20 expressed on B cells, which is effective in depleting B cells and approved worldwide for the treatment of RA. Rituximab was shown to be highly beneficial in decreasing clinical symptoms, safe, and well tolerated. However, clinical experience revealed that approximately 30-40% of RA patients do not respond to it. Given the destructive nature of RA, the risk of adverse effects, and considerable costs for therapy, there is a strong need to make predictions on the clinical outcome before the start of therapy. Since nearly all treated patients experience an effective depletion of circulating B cells, questions have been raised concerning the mechanism of action. In this review, novel developments, in particular the findings on the role of the interferon system, will be highlighted. This may add new and important information to our understanding of the mechanism that underlies the clinical outcome of rituximab treatment and may lead to the identification of biomarkers to predict the response. PMID:21955850

  20. Beneficial Effect of Rituximab in the Treatment of Recurrent Idiopathic Membranous Nephropathy after Kidney Transplantation

    PubMed Central

    Sprangers, Ben; Lefkowitz, George Ian; Cohen, Scott D.; Stokes, Michael Barry; Valeri, Antony; Appel, Gerald B.

    2010-01-01

    Background and objectives: Recurrence of the original kidney disease after renal transplantation is an increasingly recognized cause of allograft loss. Idiopathic membranous nephropathy (iMN) is a common cause of proteinuria that may progress to ESRD. It is known that iMN may recur after kidney transplantation, causing proteinuria, allograft dysfunction, and allograft loss. Limited data regarding the frequency and treatment of recurrent iMN are available. Design, setting, participants, & measurements: In this single-center study, all patients who had iMN and were receiving a first kidney transplant were included. We retrospectively assessed the incidence of biopsy-confirmed recurrent iMN and compared clinical characteristics of patients with and without recurrence. In addition, the effect of treatment with rituximab on proteinuria and renal allograft function in patients with recurrent iMN was examined Results: The incidence of recurrent iMN was 44%, and recurrences occurred at a median time of 13.6 months after transplantation. Two patterns of recurrence were identified: Early and late. No predictors of recurrence or disease progression could be identified. Treatment with rituximab was effective in four of four patients in stabilizing or reducing proteinuria and stabilizing renal function. Conclusions: Recurrence of iMN is common even in the era of modern immunosuppression. Rituximab seems to be a valuable treatment option for these patients, although lager studies are needed to confirm our data. PMID:20185599

  1. Association between -174 interleukin-6 gene polymorphism and biological response to rituximab in several systemic autoimmune diseases.

    PubMed

    Robledo, Gema; Dávila-Fajardo, Cristina Lucía; Márquez, Ana; Ortego-Centeno, Norberto; Callejas Rubio, José Luis; de Ramón Garrido, Enrique; Sánchez-Román, Julio; García-Hernández, Francisco J; Ríos-Fernández, Raquel; González-Escribano, Maria Francisca; Camps García, Maria Teresa; Castillo Palma, Maria Jesús; Ayala, Maria Del Mar; Martín, Javier

    2012-09-01

    Rituximab has become a pivotal treatment for systemic autoimmune diseases. The aim of this study was to determine whether the genetic variant -174 IL-6 contributes to differences in the response to rituximab in patients with systemic autoimmune diseases, including systemic lupus erythematosus (SLE), inflammatory myopathies, anti-neutrophil cytoplasmic antibody-mediated vasculitis, systemic sclerosis, Sjöegren's syndrome, rheumatoid arthritis, and autoimmune hemolytic anemia. DNA samples from 144 Spanish patients with different systemic autoimmune diseases receiving rituximab were genotyped for -174 IL-6 (rs1800795) gene polymorphism using the TaqMan(®) allelic discrimination technology. Six months after the first infusion with rituximab, we evaluated the response to the drug: 60.4% of the patients showed a complete response, partial 27.8%, and 11.8% did not respond to the treatment. The CC genotype frequency was significantly increased in nonresponders with respect to responders (23.5% vs. 7.1%, respectively; p=0.049; odds ratio (OR)=4.03, 95% confidence intervals (CI) 0.78-16.97). According to the genotype distribution, rituximab was effective in 69.2% of the CC carriers, 91.9% of the CG carriers, and 88.4% of the GG carriers. A similar trend was observed when SLE patients were analyzed separately (27.3% carried CC homozygosis in nonresponders and 6.9% in responders; p=0.066; OR=5.10, 95% CI 0.65-31.73). Rituximab was effective in 62.5% of the CC carriers, 88.9% of the GC carriers, and 90% of the GG carriers. These results suggest that -174 IL-6 (rs1800795) gene polymorphism plays a role in the response to rituximab in systemic autoimmune diseases. Validation of these findings in independent cohorts is warranted. PMID:22734797

  2. Anti-Apoptotic Effects of Lentiviral Vector Transduction Promote Increased Rituximab Tolerance in Cancerous B-Cells

    PubMed Central

    Ranjbar, Benyamin; Krogh, Louise Bechmann; Laursen, Maria Bach; Primo, Maria Nascimento; Marques, Sara Correia; Dybkær, Karen; Mikkelsen, Jacob Giehm

    2016-01-01

    Diffuse large B-cell lymphoma (DLBCL) is characterized by great genetic and clinical heterogeneity which complicates prognostic prediction and influences treatment efficacy. The most common regimen, R-CHOP, consists of a combination of anthracycline- and immuno-based drugs including Rituximab. It remains elusive how and to which extent genetic variability impacts the response and potential tolerance to R-CHOP. Hence, an improved understanding of mechanisms leading to drug tolerance in B-cells is crucial, and modelling by genetic intervention directly in B-cells is fundamental in such investigations. Lentivirus-based gene vectors are widely used gene vehicles, which in B-cells are an attractive alternative to potentially toxic transfection-based methodologies. Here, we investigate the use of VSV-G-pseudotyped lentiviral vectors in B-cells for exploring the impact of microRNAs on tolerance to Rituximab. Notably, we find that robust lentiviral transduction of cancerous B-cell lines markedly and specifically enhances the resistance of transduced germinal center B-cells (GCBs) to Rituximab. Although Rituximab works partially through complement-mediated cell lysis, increased tolerance is not achieved through effects of lentiviral transduction on cell death mediated by complement. Rather, reduced levels of PARP1 and persistent high levels of CD43 in Rituximab-treated GCBs demonstrate anti-apoptotic effects of lentiviral transduction that may interfere with the outcome and interpretation of Rituximab tolerance studies. Our findings stress that caution should be exercised exploiting lentiviral vectors in studies of tolerance to therapeutics in DLBCL. Importantly, however, we demonstrate the feasibility of using the lentiviral gene delivery platform in studies addressing the impact of specific microRNAs on Rituximab responsiveness. PMID:27045839

  3. Rituximab in steroid-dependent or frequently relapsing idiopathic nephrotic syndrome.

    PubMed

    Ruggenenti, Piero; Ruggiero, Barbara; Cravedi, Paolo; Vivarelli, Marina; Massella, Laura; Marasà, Maddalena; Chianca, Antonietta; Rubis, Nadia; Ene-Iordache, Bogdan; Rudnicki, Michael; Pollastro, Rosa Maria; Capasso, Giovambattista; Pisani, Antonio; Pennesi, Marco; Emma, Francesco; Remuzzi, Giuseppe

    2014-04-01

    The outcome of steroid-dependent or frequently relapsing nephrotic syndrome of minimal change disease (MCD), mesangial proliferative GN (MesGN), or FSGS may be poor and with major treatment toxicity. This academic, multicenter, off-on trial (ClinicalTrials.gov #NCT00981838) primarily evaluated the effects of rituximab therapy followed by immunosuppression withdrawal on disease recurrence in 10 children and 20 adults with MCD/MesGN (n=22) or FSGS who had suffered ≥2 recurrences over the previous year and were in steroid-induced remission for ≥1 month. Participants received one dose (n=28) or two doses of rituximab (375 mg/m(2) intravenously). At 1 year, all patients were in remission: 18 were treatment-free and 15 never relapsed. Compared with the year before rituximab treatment, total relapses decreased from 88 to 22 and the per-patient median number of relapses decreased from 2.5 (interquartile range [IQR], 2-4) to 0.5 (IQR, 0-1; P<0.001) during 1 year of follow-up. Reduction was significant across subgroups (children, adults, MCD/MesGN, and FSGS; P<0.01). After rituximab, the per-patient steroid maintenance median dose decreased from 0.27 mg/kg (IQR, 0.19-0.60) to 0 mg/kg (IQR, 0-0.23) (P<0.001), and the median cumulative dose to achieve relapse remission decreased from 19.5 mg/kg (IQR, 13.0-29.2) to 0.5 mg/kg (IQR, 0-9.4) (P<0.001). Furthermore, the mean estimated GFR increased from 111.3±25.7 to 121.8±29.2 ml/min per 1.73 m(2) (P=0.01), with the largest increases in children and in FSGS subgroups. The mean height z score slope stabilized in children (P<0.01). Treatment was well tolerated. Rituximab effectively and safely prevented recurrences and reduced the need for immunosuppression in steroid-dependent or frequently relapsing nephrotic syndrome, and halted disease-associated growth deficit in children. PMID:24480824

  4. MLN2238, a proteasome inhibitor, induces caspase-dependent cell death, cell cycle arrest, and potentiates the cytotoxic activity of chemotherapy agents in rituximab-chemotherapy-sensitive or rituximab-chemotherapy-resistant B-cell lymphoma preclinical models.

    PubMed

    Gu, Juan J; Hernandez-Ilizaliturri, Francisco J; Mavis, Cory; Czuczman, Natalie M; Deeb, George; Gibbs, John; Skitzki, Joseph J; Patil, Ritesh; Czuczman, Myron S

    2013-11-01

    To further develop therapeutic strategies targeting the proteasome system, we studied the antitumor activity and mechanisms of action of MLN2238, a reversible proteasome inhibitor, in preclinical lymphoma models. Experiments were conducted in rituximab-chemotherapy-sensitive cell lines, rituximab-chemotherapy-resistant cell lines (RRCL), and primary B-cell lymphoma cells. Cells were exposed to MLN2238 or caspase-dependent inhibitors, and differences in cell viability, alterations in apoptotic protein levels, effects on cell cycle, and the possibility of synergy when combined with chemotherapeutic agents were evaluated. MLN2238 showed more potent dose-dependent and time-dependent cytotoxicity and inhibition of cell proliferation in lymphoma cells than bortezomib. Our data suggest that MLN2238 can induce caspase-independent cell death in RRCL. MLN2238 (and to a much lesser degree bortezomib) reduced RRCL S phase and induced cell cycle arrest in the G2/M phase. Exposure of rituximab-chemotherapy-sensitive cell lines and RRCL to MLN2238 potentiated the cytotoxic effects of gemcitabine, doxorubicin, and paclitaxel and overcame resistance to chemotherapy in RRCL. MLN2238 is a potent proteasome inhibitor active in rituximab-chemotherapy-sensitive and rituximab-chemotherapy-resistant cell models and potentiates the antitumor activity of chemotherapy agents and has the potential of becoming an effective therapeutic agent in the treatment of therapy-resistant B-cell lymphoma. PMID:23995855

  5. Chimeras taking shape: potential functions of proteins encoded by chimeric RNA transcripts.

    PubMed

    Frenkel-Morgenstern, Milana; Lacroix, Vincent; Ezkurdia, Iakes; Levin, Yishai; Gabashvili, Alexandra; Prilusky, Jaime; Del Pozo, Angela; Tress, Michael; Johnson, Rory; Guigo, Roderic; Valencia, Alfonso

    2012-07-01

    Chimeric RNAs comprise exons from two or more different genes and have the potential to encode novel proteins that alter cellular phenotypes. To date, numerous putative chimeric transcripts have been identified among the ESTs isolated from several organisms and using high throughput RNA sequencing. The few corresponding protein products that have been characterized mostly result from chromosomal translocations and are associated with cancer. Here, we systematically establish that some of the putative chimeric transcripts are genuinely expressed in human cells. Using high throughput RNA sequencing, mass spectrometry experimental data, and functional annotation, we studied 7424 putative human chimeric RNAs. We confirmed the expression of 175 chimeric RNAs in 16 human tissues, with an abundance varying from 0.06 to 17 RPKM (Reads Per Kilobase per Million mapped reads). We show that these chimeric RNAs are significantly more tissue-specific than non-chimeric transcripts. Moreover, we present evidence that chimeras tend to incorporate highly expressed genes. Despite the low expression level of most chimeric RNAs, we show that 12 novel chimeras are translated into proteins detectable in multiple shotgun mass spectrometry experiments. Furthermore, we confirm the expression of three novel chimeric proteins using targeted mass spectrometry. Finally, based on our functional annotation of exon organization and preserved domains, we discuss the potential features of chimeric proteins with illustrative examples and suggest that chimeras significantly exploit signal peptides and transmembrane domains, which can alter the cellular localization of cognate proteins. Taken together, these findings establish that some chimeric RNAs are translated into potentially functional proteins in humans. PMID:22588898

  6. Rituximab for the treatment of relapsed or refractory stage III or IV follicular non-Hodgkin's lymphoma.

    PubMed

    Boland, A; Bagust, A; Hockenhull, J; Davis, H; Chu, P; Dickson, R

    2009-09-01

    This paper presents a summary of the evidence review group report into the clinical effectiveness and cost-effectiveness of rituximab for the treatment of relapsed or refractory stage III or IV follicular non-Hodgkin's lymphoma (NHL), in accordance with the licensed indication, based upon the evidence submission from Roche Products Ltd to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal (STA) process. The submitted clinical evidence included two randomised controlled trials [European Organisation for Research and Treatment of Cancer (EORTC) and German Low Grade Lymphoma Study Group - Fludarabine, Cyclophosphamide and Mitoxantrone and (GLSG-FCM)] comparing the clinical effects of chemotherapy with or without rituximab in the induction of remission at first or second relapse and the clinical benefits of rituximab maintenance therapy versus the NHS's current clinical practice of observation for follicular lymphoma (FL) patients. Both trials showed that in patients with relapsed FL the addition of rituximab to chemotherapy induction treatment increased overall response rates. Furthermore, rituximab maintenance therapy increased the median length of remission when compared with observation only. Safety data from the two trials showed that while the majority of patients reported some adverse events, the number of patients withdrawing from treatment in the EORTC trial was low, with rates not being reported for the GLSG-FCM trial. The most commonly reported adverse events were blood/bone marrow toxicity, skin rashes and allergies. The ERG reran the manufacturer's economic model after altering several of the assumptions and parameter values in order to recalculate the cost-utility ratios, quality-adjusted life-years (QALYs) and estimates of benefits. The manufacturer reported that maintenance therapy with rituximab was cost-effective compared with observation against commonly applied thresholds, with an incremental

  7. Construction, purification, and characterization of a chimeric TH1 antagonist

    PubMed Central

    Bello-Rivero, Iraldo; Torrez-Ruiz, Yeny; Blanco-Garcés, Elizabeth; Pentón-Rol, Giselle; Fernández-Batista, Osmani; Javier-González, Luís; Gerónimo-Perez, Haydee; López-Saura, Pedro

    2006-01-01

    Background TH1 immune response antagonism is a desirable approach to mitigate some autoimmune and inflammatory reactions during the course of several diseases where IL-2 and IFN-γ are two central players. Therefore, the neutralization of both cytokines could provide beneficial effects in patients suffering from autoimmune or inflammatory illnesses. Results A chimeric antagonist that can antagonize the action of TH1 immunity mediators, IFN-γ and IL-2, was designed, engineered, expressed in E. coli, purified and evaluated for its in vitro biological activities. The TH1 antagonist molecule consists of the extracellular region for the human IFNγ receptor chain 1 fused by a four-aminoacid linker peptide to human 60 N-terminal aminoacid residues of IL-2. The corresponding gene fragments were isolated by RT-PCR and cloned in the pTPV-1 vector. E. coli (W3110 strain) was transformed with this vector. The chimeric protein was expressed at high level as inclusion bodies. The protein was partially purified by pelleting and washing. It was then solubilized with strong denaturant and finally refolded by gel filtration. In vitro biological activity of chimera was demonstrated by inhibition of IFN-γ-dependent HLA-DR expression in Colo 205 cells, inhibition of IFN-γ antiproliferative effect on HEp-2 cells, and by a bidirectional effect in assays for IL-2 T-cell dependent proliferation: agonism in the absence versus inhibition in the presence of IL-2. Conclusion TH1 antagonist is a chimeric protein that inhibits the in vitro biological activities of human IFN-γ, and is a partial agonist/antagonist of human IL-2. With these attributes, the chimera has the potential to offer a new opportunity for the treatment of autoimmune and inflammatory diseases. PMID:16716222

  8. Autoantibodies induced by chimeric cytokine - HIV envelope glycoprotein immunogens

    PubMed Central

    Isik, Gözde; van Montfort, Thijs; Chung, Nancy P.Y.; Moore, John P.; Sanders, Rogier W.

    2014-01-01

    Cytokines are often used as adjuvants to increase the immunogenicity of vaccines as they can improve the immune response and/or direct it into a desired direction. As an alternative to co-delivering antigens and cytokines separately they can be fused into a composite protein, with the advantage that both moieties act on the same immune cells. The HIV-1 envelope glycoprotein (Env) spike, located on the outside of virus particles and the only relevant protein for the induction of neutralizing antibodies (NAbs), is poorly immunogenic. The induction of anti-Env Abs can be improved by coupling Env proteins to co-stimulatory molecules such as a proliferation inducing ligand (APRIL). Here, we evaluated the immunogenicity of chimeric molecules containing uncleaved Env gp140 fused to the species-matched cytokines IL-21 or GM-CSF in rabbits and mice. Each cytokine was either fused to the C-terminus of Env or embedded within Env at the position of the variable loops 1 and 2 (V1V2). The cytokine components of the chimeric Env-GM-CSF and Env-IL-21 molecules were functional in vitro, but none of the Env-cytokine fusion proteins resulted in improved Ab responses in vivo. Both the Env-GM-CSF and the Env-IL-21 molecules induced strong anti-cytokine Ab responses, in both test species. These autoimmune responses were independent of the location of the cytokine in the chimeric Env molecules; in that they were induced by cytokines inserted within the V1V2 of Env or fused to its Ct. The induction of undesired autoimmune responses should be considered when using cytokines as co-stimulatory molecules in fusion proteins. PMID:24729614

  9. Chimeric creatures in Greek mythology and reflections in science.

    PubMed

    Bazopoulou-Kyrkanidou, E

    2001-04-15

    "The Chimaera" in Homer's Iliad, "was of divine stock, not of men, in the forepart a lion, in the hinder a serpent, and in the midst a goat, ellipsis Bellerophon slew her, trusting in the signs of the gods." In Hesiod's Theogony it is emphasized that "Chimaera ellipsis had three heads, one of a grim-eyed lion, another of a goat, and another of a snakeellipsis". In addition to this interspecies animal chimera, human/animal chimeras are referred to in Greek mythology, preeminent among them the Centaurs and the Minotaur. The Centaurs, as horse/men, first appear in Geometric and early Archaic art, but in the literature not until early in the fifth century B.C. The bullheaded-man Minotaur, who is not certainly attested in the literary evidence until circa 500 B.C., first appears in art about 650 B.C. Attempts, in the fourth century B.C. and thereafter, to rationalize their mythical appearance were in vain; their chimeric nature retained its fascinating and archetypal form over the centuries. Early in the 1980s, experimental sheep/goat chimeras were produced removing the reproductive barrier between these two animal species. Late in the 1990s, legal, political, ethical, and moral fights loomed over a patent bid on human/animal chimeras. Chimeric technology is recently developed; however, the concept of chimerism has existed in literary and artistic form in ancient mythology. This is yet another example where art and literature precede scientific research and development. PMID:11337752

  10. Phase II Study of Lenalidomide and Rituximab As Salvage Therapy for Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia

    PubMed Central

    Badoux, Xavier C.; Keating, Michael J.; Wen, Sijin; Wierda, William G.; O'Brien, Susan M.; Faderl, Stefan; Sargent, Rachel; Burger, Jan A.; Ferrajoli, Alessandra

    2013-01-01

    Purpose Lenalidomide is an immunomodulatory drug active as salvage therapy for chronic lymphocytic leukemia (CLL). We combined lenalidomide with rituximab to improve response rates in patients with relapsed or refractory CLL. Patients and Methods Fifty-nine adult patients (age 42 to 82 years) with relapsed or refractory CLL were enrolled onto a phase II study of lenalidomide and rituximab. Patients had received prior fludarabine-based therapy or chemoimmunotherapy. Rituximab (375 mg/m2 intravenously) was administered weekly during cycle one and on day 1 of cycles three to 12. Lenalidomide was started on day 9 of cycle one at 10 mg orally and administered daily continuously. Each cycle was 28 days. Rituximab was administered for 12 cycles; lenalidomide could continue indefinitely if patients benefitted clinically. Results The overall response rate was 66%, including 12% complete responses and 12% nodular partial remissions. Time to treatment failure was 17.4 months. Median overall survival has not been reached; estimated survival at 36 months is 71%. The most common grade 3 or 4 toxicity was neutropenia (73% of patients). Fourteen patients (24%) experienced a grade 3 to 4 infection or febrile episode. There was one episode of grade 3 tumor lysis; one patient experienced renal failure during the first cycle of therapy, and one venous thromboembolic event occurred during the study. Conclusion The combination of lenalidomide and rituximab is active in patients with recurrent CLL and warrants further investigation. PMID:23270003

  11. Safety and efficacy of intrathecal rituximab in children with B cell lymphoid CD20+ malignancies: An international retrospective study.

    PubMed

    Ceppi, Francesco; Weitzman, Sheila; Woessmann, Wilhelm; Davies, Kimberly; Lassaletta, Alvaro; Reismüller, Bettina; Mellgren, Karin; Uyttebroeck, Anne; Maia, Iris; Abdullah, Shaker; Miakova, Natasha; Glaser, Darryl; Cohn, Richard; Abla, Oussama; Attarbaschi, Andishe; Alexander, Sarah

    2016-05-01

    Central nervous system (CNS) involvement in patients with mature B non-Hodgkin lymphoma, post-transplantation proliferative disorder and acute lymphoblastic leukemia confers a significantly inferior prognosis as compared to patients without CNS disease. Intrathecal (IT) or intraventricular administration of rituximab is an option for this group of patients. We report 25 children with CNS involvement of CD20+ B lymphoid malignancies who received in total 163 IT/intraventricular rituximab doses. The median number of doses received by each patient was 6, with a median dose of 25 mg. The most common adverse events were Grades 1 and 2 peripheral neuropathies in five patients (20%), allergy in two patients, and headache in two patients. These events were self-limited, occurring in the 48 hours after treatment and resolving within 24 hr. Three patients presented with more severe though transient side effects, one with a Grade III neuropathy and two with seizure. Eighteen patients (72%) of those treated with IT/intraventricular rituximab, with or without other CNS directed treatment, achieved a CNS remission. This case series suggests that IT/intraventricular rituximab has therapeutic efficacy and relatively limited toxicity. Prospective trials of IT/intraventricular rituximab for patients with CNS involvement of CD20 + B lymphoid malignancies are warranted. Am. J. Hematol. 91:486-491, 2016. © 2016 Wiley Periodicals, Inc. PMID:26872652

  12. Efficacy and safety of rituximab therapy for systemic lupus erythematosus: a systematic review and meta-analysis

    PubMed Central

    Lan, Lan; Han, Fei; Chen, Jiang-hua

    2012-01-01

    Objective: To review the efficacy and safety of rituximab therapy for systemic lupus erythematosus (SLE).Methods: We searched for randomized controlled trails and observational studies that evaluated the effect of rituximab based on the systemic lupus erythematosus disease activity index (SLEDAI), British Isles lupus assessment group index (BILAG), urine protein levels, and the prednisolone dose, and had adequate data to calculate the mean, standard deviation (SD), and 95% confidence intervals, and to systematically review and meta-analyze observational studies with fixed effects model or random effects model. Results: We included 2 randomized controlled studies and 19 observational clinical studies. We summarized the data from the 19 observational studies, analyzed the heterogeneity of the literature, and then used fixed effect model or random effect model for statistical analysis. The SLEDAI, BILAG, and urine protein levels and the prednisolone dosage were decreased after rituximab treatment, and the decreases in the BILAG, urine protein levels, and the prednisolone dose were found to be significant (P<0.05), when compared with baseline level. Rituximab’s adverse effects generally could be controlled with an effective dosing regimen. Conclusions: Although there are still controversies about rituximab’s treatment on SLE, but our study had showed that rituximab had favorable effects on refractory lupus. The long-term efficacy and safety of rituximab require further study. PMID:22949364

  13. Different sensitivity of rituximab-treatment to B-cells between ABO-incompatible kidney and liver transplantation.

    PubMed

    Morimoto, Hiroshi; Ide, Kentaro; Tanaka, Yuka; Ishiyama, Kohei; Ohira, Masahiro; Tahara, Hiroyuki; Akita, Tomonori; Tanaka, Junko; Ohdan, Hideki

    2016-06-01

    A desensitization protocol with rituximab is currently widely used for kidney transplantation (KT) and liver transplantation (LT) across the ABO blood group-incompatible (ABO-I) barrier. However, it remains to be elucidated whether rituximab is equally effective for B-cell and T-cell immune responses in both KT and LT recipients. To clarify these effects of rituximab, we enrolled 46 KT and 77 LT recipients in this study. The proportion of peripheral blood B-cells was determined at the perioperative period. T-cell responses to allostimulation were evaluated by a mixed lymphocyte reaction (MLR) assay. One week after rituximab administration, peripheral B-cells became undetectable in ABO-I KT recipients but remained detectable in some of the ABO-I LT recipients; B-cells were undetectable in both groups by week 2. B-cells remained below the detection limit throughout the first year in the ABO-I KT recipients, whereas they reappeared in the periphery after 6months in the ABO-I LT recipients. There were no significant differences in alloreactive T-cell responses based on MLR analyses between ABO-I and ABO-compatible groups. This study indicates that rituximab has differing B-cell sensitivity between KT and LT recipients and a minimal effect on the alloreactive T-cell responses in KT and LT recipients. PMID:27085793

  14. Bioengineered Chimeric Spider Silk-Uranium Binding Proteins

    PubMed Central

    Krishnaji, Sreevidhya Tarakkad; Kaplan, David L.

    2014-01-01

    Heavy metals constitute a source of environmental pollution. Here, novel functional hybrid biomaterials for specific interactions with heavy metals are designed by bioengineering consensus sequence repeats from spider silk of Nephila clavipes with repeats of a uranium peptide recognition motif from a mutated 33-residue of calmodulin protein from Paramecium tetraurelia. The self-assembly features of the silk to control nanoscale organic/inorganic material interfaces provides new biomaterials for uranium recovery. With subsequent enzymatic digestion of the silk to concentrate the sequestered metals, options can be envisaged to use these new chimeric protein systems in environmental engineering, including to remediate environments contaminated by uranium. PMID:23212989

  15. A PCR amplification strategy for unrestricted generation of chimeric genes.

    PubMed

    Vos, Michel J; Kampinga, Harm H

    2008-09-15

    For analyzing protein function, protein dynamics, or protein-protein interactions, the use of chimeric proteins has become an indispensable tool. The generation of DNA constructs coding for such fused proteins can, however, be a tedious process. Currently used strategies often make use of available endonuclease sites, leading to limitations in the choice of the site of fusion between two genes and problems in maintaining protein secondary structure. We have developed a cloning strategy to get around these disadvantages that is based on a single round of PCR amplification followed by antibiotic-resistant gene complementation. PMID:18555003

  16. Chimeric Anterolateral Thigh Flap for Total Thoracic Esophageal Reconstruction.

    PubMed

    Ruiz-Moya, Alejandro; Segura-Sampedro, Juan J; Sicilia-Castro, Domingo; Carvajo-Pérez, Francisco; Gómez-Cía, Tomás; Vázquez-Medina, Antonio; Ibáñez-Delgado, Francisco

    2016-01-01

    Gastric pull-up is generally the first choice for a total thoracic esophageal reconstruction. Malfunction of this gastric conduit is uncommon, but devastating when it occurs: it causes marked comorbidity to the patient, preventing oral intake and worsening quality of life. Secondary salvage thoracic esophageal reconstruction surgery is usually performed with free or pedicled jejunum flaps or colon interposition. We present a case of a total thoracic esophageal reconstruction with an externally monitored chimeric anterolateral thigh flap, extending from the cervical esophagus to the retrosternal gastroplasty remnant. Intestinal reconstructive techniques were not an available option for this patient. PMID:26694271

  17. The basic principles of chimeric antigen receptor (CAR) design

    PubMed Central

    Sadelain, Michel; Brentjens, Renier; Riviere, Isabelle

    2013-01-01

    CARs are recombinant receptors that provide both antigen-binding and T cell activating functions. A multitude of CARs has been reported over the past decade, targeting an array of cell surface tumor antigens. Their biological functions have dramatically changed following the introduction of tri-partite receptors comprising a costimulatory domain, termed second generation CARs. These have recently demonstrated clinical benefit in patients treated with CD19-targeted autologous T cells. CARs may be combined with costimulatory ligands, chimeric costimulatory receptors or cytokines to further enhance T cell potency, specificity and safety. CARs represent a new class of drugs with exciting potential for cancer immunotherapy. PMID:23550147

  18. Chimeric antigen receptor T-cell therapy for solid tumors

    PubMed Central

    Newick, Kheng; Moon, Edmund; Albelda, Steven M

    2016-01-01

    Chimeric antigen receptor (CAR) T cells are engineered constructs composed of synthetic receptors that direct T cells to surface antigens for subsequent elimination. Many CAR constructs are also manufactured with elements that augment T-cell persistence and activity. To date, CAR T cells have demonstrated tremendous success in eradicating hematological malignancies (e.g., CD19 CARs in leukemias). This success is not yet extrapolated to solid tumors, and the reasons for this are being actively investigated. Here in this mini-review, we discuss some of the key hurdles encountered by CAR T cells in the solid tumor microenvironment. PMID:27162934

  19. Progressive multifocal leukoencephalopathy after rituximab therapy in HIV-negative patients: a report of 57 cases from the Research on Adverse Drug Events and Reports project

    PubMed Central

    Carson, Kenneth R.; Evens, Andrew M.; Richey, Elizabeth A.; Habermann, Thomas M.; Focosi, Daniele; Seymour, John F.; Laubach, Jacob; Bawn, Susie D.; Gordon, Leo I.; Winter, Jane N.; Furman, Richard R.; Vose, Julie M.; Zelenetz, Andrew D.; Mamtani, Ronac; Raisch, Dennis W.; Dorshimer, Gary W.; Rosen, Steven T.; Muro, Kenji; Gottardi-Littell, Numa R.; Talley, Robert L.; Sartor, Oliver; Green, David; Major, Eugene O.

    2009-01-01

    Rituximab improves outcomes for persons with lymphoproliferative disorders and is increasingly used to treat immune-mediated illnesses. Recent reports describe 2 patients with systemic lupus erythematosus and 1 with rheumatoid arthritis who developed progressive multifocal leukoencephalopathy (PML) after rituximab treatment. We reviewed PML case descriptions among patients treated with rituximab from the Food and Drug Administration, the manufacturer, physicians, and a literature review from 1997 to 2008. Overall, 52 patients with lymphoproliferative disorders, 2 patients with systemic lupus erythematosus, 1 patient with rheumatoid arthritis, 1 patient with an idiopathic autoimmune pancytopenia, and 1 patient with immune thrombocytopenia developed PML after treatment with rituximab and other agents. Other treatments included hematopoietic stem cell transplantation (7 patients), purine analogs (26 patients), or alkylating agents (39 patients). One patient with an autoimmune hemolytic anemia developed PML after treatment with corticosteroids and rituximab, and 1 patient with an autoimmune pancytopenia developed PML after treatment with corticosteroids, azathioprine, and rituximab. Median time from last rituximab dose to PML diagnosis was 5.5 months. Median time to death after PML diagnosis was 2.0 months. The case-fatality rate was 90%. Awareness is needed of the potential for PML among rituximab-treated persons. PMID:19264918

  20. 78 FR 16505 - Prospective Grant of Exclusive License: Chimeric West Nile/Dengue Viruses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ...: Chimeric West Nile/Dengue Viruses AGENCY: Centers for Disease Control and Prevention (CDC), Department of... license, in the field of use of in vitro diagnostics for dengue virus infection, to practice the... Application 61/049,342, filed 4/30/2008, entitled ``Engineered, Chimeric West Nile/Dengue Viruses;''...

  1. Rapid infusion rituximab in combination with corticosteroid-containing chemotherapy or as maintenance therapy is well tolerated and can safely be delivered in the community setting.

    PubMed

    Sehn, Laurie H; Donaldson, Jane; Filewich, Allison; Fitzgerald, Catherine; Gill, Karamjit K; Runzer, Nancy; Searle, Barb; Souliere, Sheila; Spinelli, John J; Sutherland, Judy; Connors, Joseph M

    2007-05-15

    The increasing usage of rituximab in the management of non-Hodgkin lymphoma (NHL) has created huge logistical challenges with respect to the delivery of this time- and labor-intensive drug. To address these challenges, we developed and tested the feasibility of a 90-minute infusion schedule for rituximab (20% of the dose administered in the first 30 minutes, remaining 80% administered over 60 minutes). A safety analysis performed in 150 patients receiving rituximab with corticosteroid-containing chemotherapy and 56 patients receiving rituximab as maintenance therapy demonstrated that this schedule was well tolerated, with no grade 3 or 4 infusion reactions observed. In addition, no increase in minor reactions was noted. More than 1200 patients have been treated with this rapid rituximab infusion schedule in the province of British Columbia (BC), demonstrating its safety in the community setting. The adoption of this 90-minute schedule as standard practice has had a positive impact on resource utilization. PMID:17244675

  2. A Case of Fulminant Hepatitis due to Echovirus 9 in a Patient on Maintenance Rituximab Therapy for Follicular Lymphoma

    PubMed Central

    Thomson, S. J.; Legg, Joanne; Narat, Santosh

    2015-01-01

    Rituximab is a CD20 monoclonal antibody commonly used in the treatment of haematological malignancies. It causes lymphopenia with subsequent compromised humoral immunity resulting in an increased risk of infection. A number of infections and viral reactivations have been described as complicating Rituximab therapy. We report an apparently unique case of echovirus 9 (an enterovirus) infection causing an acute hepatitis and significant morbidity in an adult patient on maintenance treatment of Rituximab for follicular lymphoma. We also describe potential missed opportunities to employ more robust screening for viral infections which may have prevented delays in the appropriate treatment and thus may have altered the patient's clinical course. We also make suggestions for lowering the threshold of viral testing in similar patients in the future. PMID:26106492

  3. [Successful treatment with rituximab in two cases of IgM-monoclonal gammopathy of undetermined significance (MGUS) neuropathy].

    PubMed

    Koike, Michiaki; Sugimoto, Keiji; Tusui, Miyuki; Yahata, Yuriko

    2012-04-01

    A 66-year-old male was hospitalized with muscle weakness and gait disturbance. Examination revealed IgM 3,407 mg/dl (IgM, κ-type M protein) and he was diagnosed as having IgM-MGUS neuropathy. He suffered from paralysis of respiratory muscles and required a respirator support. Plasmapheresis and intravenous immunoglobulin were performed and he was weaned from the respirator. Rituximab given as 8 weekly infusions improved gait disturbance. A 71-year-old male was hospitalized with lumbago, numbness of lower extremities and gait disturbance. Examination revealed IgM 1,553 mg/dl (IgM, λ-type M protein) and he was diagnosed with IgM-MGUS neuropathy. Rituximab given as 8 weekly infusions improved gait disturbance. It was concluded that rituximab is a well-tolerated treatment that may be effective in some patients with IgM-MGUS neuropathy. PMID:22687979

  4. Delayed-onset grade 4 neutropenia associated with rituximab therapy in a patient with lymphoma: case report and literature review.

    PubMed

    Motl, Susannah E; Baskin, Reed C

    2005-08-01

    A 53-year-old man developed delayed-onset neutropenia 6 weeks after completing first-line therapy with rituximab, cyclophosphamide, mitoxantrone, vincristine, and prednisone for high-grade B-cell lymphoma. Bone marrow biopsy demonstrated hypercellular marrow with normal maturation. He also developed interstitial pneumonitis, an adverse event associated with rituximab use. Infiltrates of T cells were found in the patient's lungs. For the next 6 months, the patient required subcutaneous granulocyte colony-stimulating factor 300 mug twice/week to maintain a granulocyte count above 1000 cells/mm3. He also received oral antibiotics for mouth sores and thrush. Based on the existing evidence, monitoring blood counts for as long as 8 weeks after rituximab therapy may be advisable, although the literature reports that neutropenia can develop up to 1 year after treatment. The development of a registry and uniform testing may help uncover the cause of this delayed-onset neutropenia. PMID:16207108

  5. Could we use a lower dose of rituximab to treat rheumatoid arthritis in clinical practice: pros and cons?

    PubMed

    Ferraccioli, Gianfranco; Tolusso, Barbara; Gremese, Elisa

    2016-01-01

    The CERERRA database provides evidence that low-dose rituximab performs as well as the conventional dose in the real world, thus highlighting the possible pharmacoeconomic impact. In clinical trials, it has been shown that rituximab 500 mg twice, performs as well as 1 g twice, 2 weeks apart, in terms of the American College of Rheumatology (ACR)20 and ACR50, but not the ACR70. The choice should always be made after considering that the IMAGE trial has demonstrated similar radiographic progression after the first 6 months, but with less control, with low-dose rituximab in the first 6 months. A possible alternative can be hypothesized. PMID:27255529

  6. Chimeric Antisense Oligonucleotide Conjugated to α-Tocopherol

    PubMed Central

    Nishina, Tomoko; Numata, Junna; Nishina, Kazutaka; Yoshida-Tanaka, Kie; Nitta, Keiko; Piao, Wenying; Iwata, Rintaro; Ito, Shingo; Kuwahara, Hiroya; Wada, Takeshi; Mizusawa, Hidehiro; Yokota, Takanori

    2015-01-01

    We developed an efficient system for delivering short interfering RNA (siRNA) to the liver by using α-tocopherol conjugation. The α-tocopherol–conjugated siRNA was effective and safe for RNA interference–mediated gene silencing in vivo. In contrast, when the 13-mer LNA (locked nucleic acid)-DNA gapmer antisense oligonucleotide (ASO) was directly conjugated with α-tocopherol it showed markedly reduced silencing activity in mouse liver. Here, therefore, we tried to extend the 5′-end of the ASO sequence by using 5′-α-tocopherol–conjugated 4- to 7-mers of unlocked nucleic acid (UNA) as a “second wing.” Intravenous injection of mice with this α-tocopherol–conjugated chimeric ASO achieved more potent silencing than ASO alone in the liver, suggesting increased delivery of the ASO to the liver. Within the cells, the UNA wing was cleaved or degraded and α-tocopherol was released from the 13-mer gapmer ASO, resulting in activation of the gapmer. The α-tocopherol–conjugated chimeric ASO showed high efficacy, with hepatic tropism, and was effective and safe for gene silencing in vivo. We have thus identified a new, effective LNA-DNA gapmer structure in which drug delivery system (DDS) molecules are bound to ASO with UNA sequences. PMID:25584900

  7. Design of Chimeric Levansucrases with Improved Transglycosylation Activity

    PubMed Central

    Olvera, Clarita; Centeno-Leija, Sara; Ruiz-Leyva, Paulina

    2012-01-01

    Fructansucrases (FSs), including levansucrases and inulosucrases, are enzymes that synthesize fructose polymers from sucrose by the direct transfer of the fructosyl moiety to a growing polymer chain. These enzymes, particularly the single domain fructansucrases, also possess an important hydrolytic activity, which may account for as much as 70 to 80% of substrate conversion, depending on reaction conditions. Here, we report the construction of four chimeric levansucrases from SacB, a single domain levansucrase produced by Bacillus subtilis. Based on observations derived from the effect of domain deletion in both multidomain fructansucrases and glucansucrases, we attached different extensions to SacB. These extensions included the transitional domain and complete C-terminal domain of Leuconostoc citreum inulosucrase (IslA), Leuconostoc mesenteroides levansucrase (LevC), and a L. mesenteroides glucansucrase (DsrP). It was found that in some cases the hydrolytic activity was reduced to less than 10% of substrate conversion; however, all of the constructs were as stable as SacB. This shift in enzyme specificity was observed even when the SacB catalytic domain was extended only with the transitional region found in multidomain FSs. Specific kinetic analysis revealed that this change in specificity of the SacB chimeric constructs was derived from a 5-fold increase in the transfructosylation kcat and not from a reduction of the hydrolytic kcat, which remained constant. PMID:22247149

  8. Tetrahydroisoquinolinone-based Steroidomimetic and Chimeric Microtubule Disruptors

    PubMed Central

    Leese, Mathew P.; Jourdan, Fabrice L.; Major, Meriel R.; Dohle, Wolfgang; Hamel, Ernest; Ferrandis, Eric; Fiore, Ann; Kasprzyk, Philip G.; Potter, Barry V. L.

    2013-01-01

    A SAR translation strategy was used for the discovery of tetrahydroisoquinoline (THIQ)-based steroidomimetic and chimeric microtubule disruptors based upon a steroidal starting point. A steroid A,B-ring-mimicking THIQ core was connected to methoxy aryl D-ring ring mimics through methylene, carbonyl and sulfonyl linkers to afford a number of steroidomimetic hits (e.g. 20c GI50 2.1 μM). Optimisation and control experiments demonstrate the complementary SAR of this series and the steroid derivatives that inspired its design. Linkage of the THIQ-based A,B-mimic with the trimethoxy aryl motif prevalent in colchicine site binding microtubule disruptors delivered a series of chimeric molecules whose activity (to GI50 40 nM) surpasses that of the parent steroid derivatives. Validation of this strategy was obtained from the excellent oral activity of 20z relative to a benchmark steroidal bis-sulfamate in an in vivo model of multiple myeloma. PMID:24124095

  9. Incorporation of chimeric gag protein into retroviral particles.

    PubMed Central

    Weldon, R A; Erdie, C R; Oliver, M G; Wills, J W

    1990-01-01

    The product of the Rous sarcoma virus (RSV) gag gene, Pr76gag, is a polyprotein precursor which is cleaved by the viral protease to yield the major structural proteins of the virion during particle assembly in avian host cells. We have recently shown that myristylated forms of the RSV Gag protein can induce particle formation with very high efficiency when expressed in mammalian cells (J. W. Wills, R. C. Craven, and J. A. Achacoso, J. Virol. 63:4331-4343, 1989). We made use of this mammalian system to examine the abilities of foreign antigens to be incorporated into particles when fused directly to the myristylated Gag protein. Our initial experiments showed that removal of various portions of the viral protease located at the carboxy terminus of the RSV Gag protein did not disrupt particle formation. We therefore chose this region for coupling of iso-1-cytochrome c from Saccharomyces cerevisiae to Gag. This was accomplished by constructing an in-frame fusion of the CYC1 and gag coding sequences at a common restriction endonuclease site. Expression of the chimeric gene resulted in synthesis of the Gag-cytochrome fusion protein and its release into the cell culture medium. The chimeric particles were readily purified by simple centrifugation, and transmission electron microscopy of cells that produced them revealed a morphology similar to that of immature type C retrovirions. Images PMID:2166812

  10. Mixed chimerism to induce tolerance for solid organ transplantation

    SciTech Connect

    Wren, S.M.; Nalesnik, M.; Hronakes, M.L.; Oh, E.; Ildstad, S.T. )

    1991-04-01

    Chimerism, or the coexistence of tissue elements from more than one genetically different strain or species in an organism, is the only experimental state that results in the induction of donor-specific transplantation tolerance. Transplantation of a mixture of T-cell-depleted syngeneic (host-type) plus T-cell-depleted allogeneic (donor) bone marrow into a normal adult recipient mouse (A + B----A) results in mixed allogeneic chimerism. Recipient mice exhibit donor-specific transplantation tolerance, yet have full immunocompetence to recognize and respond to third-party transplantation antigens. After complete hematolymphopoietic repopulation at 28 days, animals accept a donor-specific skin graft but reject major histocompatibility complex (MHC) locus-disparate third-party grafts. We now report that permanent graft acceptance can also be achieved when the graft is placed at the time of bone marrow transplantation. Histologically, grafts were viable and had only minimal inflammatory changes. This model may have potential future clinical application for the induction of donor-specific transplantation tolerance.

  11. Human Cytokine Genetic Variants Associated With HBsAg Reverse Seroconversion in Rituximab-Treated Non-Hodgkin Lymphoma Patients

    PubMed Central

    Hsiao, Liang-Tsai; Wang, Hao-Yuan; Yang, Ching-Fen; Chiou, Tzeon-Jye; Gau, Jyh-Pyng; Yu, Yuan-Bin; Liu, Hsiao-Ling; Chang, Wen-Chun; Chen, Po-Min; Tzeng, Cheng-Hwai; Chan, Yu-Jiun; Yang, Muh-Hwa; Liu, Jin-Hwang; Huang, Yi-Hsiang

    2016-01-01

    Abstract Hepatitis B virus (HBV) reactivation has been noted in HBV surface antigen (HBsAg)-seronegative patients with CD20+ B-cell non-Hodgkin lymphoma (NHL) undergoing rituximab treatment. Clinically, hepatitis flares are usually associated with the reappearance of HBsAg (reverse seroconversion of HBsAg, HBV-RS). It is unclear whether human genetic factors are related to rituximab-associated HBV reactivation. Unvaccinated HBsAg-seronegative adults (n = 104) with CD20+ NHL who had received rituximab-containing therapy without anti-HBV prophylaxis were enrolled. Eighty-nine candidate single nucleotide polymorphisms (SNPs) of 49 human cytokine genes were chosen and were analyzed using the iPLEX technique. Competing risk regression was used to identify the factors associated with HBV-RS. Participants had a median age of 66.1 years and 56.7% were male (n = 59). The anti-HBs and anti-HBc positivity rates were 82.4% and 94.1%, respectively, among patients for whom data were available (approximately 81%). A mean of 7.14 cycles of rituximab therapy were administered, and a total of 14 (13.4%) patients developed HBV-RS. Nine SNPs showed significant differences in frequency between patients with or without HBV-RS: CD40 rs1883832, IL4 rs2243248 and rs2243263, IL13 rs1295686, IL18 rs243908, IL20 rs1518108, and TNFSF13B rs12428930 and rs12583006. Multivariate analysis showed that ≥6 cycles of rituximab therapy, IL18 rs243908, and the IL4 haplotype rs2243248∼rs2243263 were independently associated with HBV-RS. The IL4 haplotype rs2243248∼rs2243263 was significantly associated with HBV-RS regardless of anti-HBs status. Polymorphisms in human cytokine genes impact the risk of rituximab-associated HBV-RS. PMID:26986131

  12. Rituximab in the Treatment of Refractory Adult and Juvenile Dermatomyositis and Adult Polymyositis: A Randomized, Placebo-phase Trial

    PubMed Central

    Oddis, Chester V.; Reed, Ann M.; Aggarwal, Rohit; Rider, Lisa G.; Ascherman, Dana P.; Levesque, Marc C.; Barohn, Richard J.; Feldman, Brian M.; Harris-Love, Michael O.; Koontz, Diane C.; Fertig, Noreen; Kelley, Stephanie S.; Pryber, Sherrie L.; Miller, Frederick W.; Rockette, Howard E.

    2012-01-01

    Objective To assess the safety and efficacy of rituximab in a randomized, double-blind, placebo-phase, trial of adult and pediatric myositis. Methods Adults with refractory polymyositis and adults and children with refractory dermatomyositis were enrolled. Entry criteria included muscle weakness and ≥2 additional abnormal core set measures (CSM) for adults. JDM patients required ≥ 3 abnormal CSM with or without muscle weakness. Patients were randomized to either ‘rituximab early’ or ‘rituximab late’ and glucocorticoid and immunosuppressive therapy were allowed at entry. The primary endpoint compared the time to achieve the preliminary International Myositis Assessment and Clinical Studies Group definition of improvement (DOI) between the 2 groups. The secondary endpoints were time to achieve ≥20% improvement in muscle strength, and the proportion of early and late rituximab patients achieving DOI at week 8. Results Among 200 randomized patients (76 PM/76 DM/48 JDM), 195 showed no difference in the time to DOI between the rituximab late (n=102) and rituximab early (n=93) groups (p=0.74, log rank) with a median time to DOI of 20.2 weeks and 20.0 weeks respectively. The secondary endpoints also did not significantly differ between the two treatment groups. However, 161 (83%) of randomized patients met the DOI and individual CSM improved in both groups throughout the 44-week trial. Conclusion Although there were no significant differences in the two treatment arms for the primary and secondary endpoints, 83% of refractory adult and juvenile myositis patients met the DOI. The role of B cell depleting therapies in myositis warrants further study with consideration for a different trial design. PMID:23124935

  13. Rituximab therapy for chonic and refractory immune thrombocytopenic purpura: a long-term follow-up analysis

    PubMed Central

    Garcia-Chavez, Jaime; Montiel-Cervantes, Laura; Esparza, Miriam García-Ruiz; Vela-Ojeda, Jorge

    2007-01-01

    The aim of this study was to evaluate the long-term response to rituximab in patients with chronic and refractory immune thrombocytopenic purpura (ITP). Adults with ITP fail to respond to conventional therapies in almost 30% of cases, developing a refractory disease. Rituximab has been successfully used in these patients. We used rituximab at 375 mg/m2, IV, weekly for a total of four doses in 18 adult patients. Complete remission (CR) was considered if the platelet count was >100 × 109/l, partial remission (PR) if platelets were >50 × 109/l, minimal response (MR) if the platelet count was >30 × 109/l and <50 × 109/l, and no response if platelet count remained unchanged. Response was classified as sustained (SR) when it was stable for a minimum of 6 months. Median age was 43.5 years (range, 17 to 70). Median platelet count at baseline was 12.5 × 109/l (range, 3.0 to 26.3). CR was achieved in five patients (28%), PR in five (28%), MR in four (22%), and two patients were classified as therapeutic failures (11%). Two additional patients were lost to follow-up. The median time between rituximab therapy and response was 14 weeks (range, 4 to 32). SR was achieved in 12 patients (67%). There were no severe adverse events during rituximab therapy. During follow-up (median, 26 months; range, 12 to 59), no other immunosuppressive drugs were used. In conclusion, rituximab therapy is effective and safe in adult patients with chronic and refractory ITP. Overall response rate achieved is high, long term, and with no risk of adverse events. PMID:17874322

  14. Cytomegalovirus infection in autologous stem cell transplant recipients in the era of rituximab.

    PubMed

    Jain, Tania; John, Jisha; Kotecha, Aditya; Deol, Abhinav; Saliminia, Tanaz; Revankar, Sanjay; Chandrasekar, Pranatharthi

    2016-08-01

    The incidence of cytomegalovirus (CMV) reactivation/disease after autologous stem cell transplant (ASCT) is much lower than that after allogeneic stem cell transplantation. With the recent use of rituximab during cancer chemotherapy or conditioning regimens prior to transplantation, there has been an increasing concern of opportunistic infections including CMV. In the present study, we reviewed the patients undergoing ASCT from December 2007 to December 2013 to identify those developing CMV reactivation/disease. Out of the 978 patients who underwent ASCT at the Karmanos Cancer Institute, 239 patients were tested for symptomatic CMV reactivation based on clinical suspicion. Of the tested patients, 7/239 (2.9 %) were documented to have CMV reactivation within 90 days of ASCT. The median time to develop CMV viremia was 32 days from transplantation. Of the 239 patients tested, CMV viremia was detected in 3 out of 72 patients who received rituximab as compared to 4 out of 167 patients who did not. Three of these seven viremic patients were treated with anti-viral drugs; viremia resolved in all patients at a median of 24 days. Three patients were found to develop other bacterial and/or fungal infections following CMV viremia. Two of the seven patients died during 1-year follow-up, due to primary disease progression or Candida sepsis. None of the patients developed proven tissue-invasive CMV disease. The study did not evaluate the incidence of asymptomatic CMV infection/reactivation. Despite prior publications based on limited data, rituximab does not appear to contribute to an increased frequency of symptomatic CMV reactivation following ASCT. PMID:27225264

  15. Rituximab for the Treatment of IgG4-Related Tubulointerstitial Nephritis

    PubMed Central

    McMahon, Blaithin A.; Novick, Tessa; Scheel, Paul J.; Bagnasco, Serena; Atta, Mohamed G.

    2015-01-01

    Abstract Immunoglobulin type gamma 4 (IgG4)-related disease is a relatively newly described clinical entity characterized by a distinctive histopathological appearance, increased numbers of IgG4 positive plasma cells and often, but not always, elevated serum IgG4 concentrations. The most common renal manifestation of IgG4-related disease is tubulointerstitial nephritis marked with proteinuria, hematuria, decreased kidney function, hypocomplementemia, and radiologic abnormalities. Renal biopsy characteristics include dense lymphoplasmacytic tubulointerstitial nephritis that stains for IgG4, storiform fibrosis, and immune complex deposition in the interstitium and along tubule basement membranes. Treatment traditionally consists of prolonged glucocorticoids but cases refractory to glucocorticoids have been reported. We report a case of a 58-year-old Caucasian man who presented with fatigue, 50 pound weight loss, dyspnea, lymphadenopathy, and nephromegaly. The patient was first misdiagnosed as chronic interstitial nephritis secondary to renal sarcoid and was treated with repeated doses of prednisone. On his third relapse, he underwent a repeat renal biopsy and a diagnosis of IgG4-tubulointerstitial nephritis was confirmed. He was refractory to treatment with prednisone. The patient received Rituximab and had prompt sustained improvement in renal function. At 1 year post Rituximab treatment, his serum creatinine remains at baseline and imaging study revealed reduction in his kidney size. This is the first case report using Rituximab as a steroid sparing option for refractory IgG4-tubulointerstitial nephritis. More information is needed on the long-term effects of using of B-cell depleting agents for glucocorticoid resistant IgG4-tubulointerstitial nephritis. PMID:26266393

  16. In Vitro Cytotoxicity of Low-Dose-Rate Radioimmunotherapy by the Alpha-Emitting Radioimmunoconjugate Thorium-227-DOTA-Rituximab

    SciTech Connect

    Dahle, Jostein; Krogh, Cecilie; Melhus, Katrine B.; Borrebaek, Jorgen; Larsen, Roy H.; Kvinnsland, Yngve

    2009-11-01

    Purpose: To determine whether the low-dose-rate alpha-particle-emitting radioimmunoconjugate {sup 227}Th-1,4,7,10-p-isothiocyanato-benzyl-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (DOTA)-rituximab can be used to inactivate lymphoma cells growing as single cells and small colonies. Methods and Materials: CD20-positive lymphoma cell lines were treated with {sup 227}Th-DOTA-rituximab for 1-5 weeks. To simulate the in vivo situation with continuous but decreasing supply of radioimmunoconjugates from the blood pool, the cells were not washed after incubation with {sup 227}Th-DOTA-rituximab, but half of the medium was replaced with fresh medium, and cell concentration and cell-bound activity were determined every other day after start of incubation. A microdosimetric model was established to estimate the average number of hits in the nucleus for different localizations of activity. Results: There was a specific targeted effect on cell growth of the {sup 227}Th-DOTA-rituximab treatment. Although the cells were not washed after incubation with {sup 227}Th-DOTA-rituximab, the average contribution of activity in the medium to the mean dose was only 6%, whereas the average contribution from activity on the cells' own surface was 78%. The mean dose rates after incubation with 800 Bq/mL {sup 227}Th-DOTA-rituximab varied from 0.01 to 0.03 cGy/min. The average delay in growing from 10{sup 5} to 10{sup 7} cells/mL was 15 days when the cells were treated with a mean absorbed radiation dose of 2 Gy alpha-particle radiation from {sup 227}Th-DOTA-rituximab, whereas it was 11 days when the cells were irradiated with 6 Gy of X-radiation. The relative biologic effect of the treatment was estimated to be 2.9-3.4. Conclusions: The low-dose-rate radioimmunoconjugate {sup 227}Th-DOTA-rituximab is suitable for inactivation of single lymphoma cells and small colonies of lymphoma cells.

  17. Late Occurrence of PML in a Patient Treated for Lymphoma with Immunomodulatory Chemotherapies, Bendamustine, Rituximab, and Ibritumomab Tiuxetan

    PubMed Central

    Lane, Michael A.; Renga, Vijay; Pachner, Andrew R.; Cohen, Jeffrey A.

    2015-01-01

    PML caused by John Cunningham (JC) virus is a rare but an increasingly recognized entity. With the advent of newer immunomodulatory therapies with monoclonal antibodies, there is an increasing incidence of PML. Initially concern was restricted to patients treated for multiple sclerosis with natalizumab but more case reports are being reported during treatment for other conditions like Crohn's disease and lymphoma with agents such as rituximab. We report the case of a 66-year-old woman who developed PML a year after completion of therapy with rituximab, ibritumomab, and bendamustine. PMID:25705531

  18. Risk of Reverse Seroconversion of Hepatitis B Virus Surface Antigen in Rituximab-Treated Non-Hodgkin Lymphoma Patients

    PubMed Central

    Hsiao, Liang-Tsai; Chiou, Tzeon-Jye; Gau, Jyh-Pyng; Yang, Ching-Fen; Yu, Yuan-Bin; Liu, Chun-Yu; Liu, Jin-Hwang; Chen, Po-Min; Tzeng, Cheng-Hwai; Chan, Yu-Jiun; Yang, Muh-Hwa; Huang, Yi-Hsiang

    2015-01-01

    Abstract Rituximab causes hepatitis B virus (HBV) reactivation in HBV surface antigen (HBsAg)-seronegative patients with CD20-positive B-cell non-Hodgkin lymphoma (CD20+ NHL), especially for those seropositive to the antibody of core antigen (anti-HBc). Clinical hepatitis usually develops after reverse seroconversion of HBsAg (HBV-RS), indicated by the reappearance of HBsAg in serum. Because of the relatively high prevalence of anti-HBc seropositivity in unvaccinated HBsAg-seronegative adults in an HBV hyperendemic area, we aimed to investigate additional factors influencing the development of rituximab-associated HBV-RS. Between January 2000 and December 2010, unvaccinated HBsAg-seronegative adults with CD20+ NHL who had received rituximab-containing therapy but not anti-HBV agents were enrolled. Patients with and without HBV-RS were compared in terms of clinical factors and treatments including the number of cycles of rituximab therapy, and transplantation. Competing risk regression was used to identify the factors associated with HBV-RS. For the 482 patients enrolled, the serological status of anti-HBc was available in 75.9%, with a seropositivity rate of 86.6%. At the last follow-up, a total of 33 (6.85%) patients had HBV-RS, with 95.8% anti-HBc seropositive, 78.9% anti-HBs seropositive, and none anti-HCV seropositive. HBV-RS patients have received more cycles (≥6) and prolonged durations of rituximab therapy, and hematopoietic stem cell transplantation. The overall survival was not different between patients with and those without HBV-RS. At the time of HBV-RS, a total of 25 (78.1%) patients had hepatitis flare, especially when HBV-RS appeared during/after induction therapy (100%, 10 of 10). Three (9.1%) patients had fulminant hepatitis, resulting in death in 1 (3%) patient. A higher rituximab cycle intensity was associated with a higher rate of hepatitis flare at the time of HBV-RS. When death in the absence of HBV-RS was considered as the competing risk

  19. Standard Operating Procedure for In-house Preparation of (131)I-rituximab for Radioimmunotherapy of Non-Hodgkin's Lymphoma.

    PubMed

    Pickford, Matthew D; Turner, J Harvey

    2012-09-01

    A Standard Operating Procedure (SOP) has been formulated for in-house preparation, quality control, dispensing and administration of (131)I-rituximab appropriate for the safe, effective, radioimmunotherapy of non-Hodgkin lymphoma. A decade of experience of semi-automated radioiodination of rituximab in our hospital radiopharmaceutical laboratory was analysed. The methodology was then refined for safe, practical, affordable application to radioimmunotherapy of lymphoma in departments of nuclear medicine in developing countries. This SOP has the potential to be incorporated into good laboratory practice conditions appropriate for local regulatory agency requirements. PMID:23372447

  20. Standard Operating Procedure for In-house Preparation of 131I-rituximab for Radioimmunotherapy of Non-Hodgkin's Lymphoma

    PubMed Central

    Pickford, Matthew D.; Turner, J. Harvey

    2012-01-01

    A Standard Operating Procedure (SOP) has been formulated for in-house preparation, quality control, dispensing and administration of 131I-rituximab appropriate for the safe, effective, radioimmunotherapy of non-Hodgkin lymphoma. A decade of experience of semi-automated radioiodination of rituximab in our hospital radiopharmaceutical laboratory was analysed. The methodology was then refined for safe, practical, affordable application to radioimmunotherapy of lymphoma in departments of nuclear medicine in developing countries. This SOP has the potential to be incorporated into good laboratory practice conditions appropriate for local regulatory agency requirements. PMID:23372447

  1. Protein-losing enteropathy associated with refractory systemic lupus erythematosus with a good response to rituximab.

    PubMed

    Sansinanea, Pierina; Carrica, Sebastián Augusto; Marcos, Josefina; García, Mercedes Argentina

    2016-01-01

    A case is presented of a protein-losing enteropathy (PLE) as the initial manifestation of systemic lupus erythematosus (SLE) in a 17 year-old female patient, who presented with ascites, edema and hypoalbuminemia. The diagnosis of SLE was based on the presence of: malar rash, oral ulcers, thrombocytopenia, antinuclear antibodies, IgM anticardiolipin antibody, and lupus anticoagulant. Renal and liver diseases were ruled out. The PLE diagnosis was confirmed with fecal alpha 1-antitrypsin clearance. The PLE was refractory to different lines of immunosuppressive agents like glucocorticoids, cyclophosphamide, azathioprine, and cyclosporine, showing a satisfactory and sustained response with rituximab, allowing steroid sparing and long term remission. PMID:25818375

  2. Steroid Refractory Autoimmune Haemolytic Anaemia Secondary to Sarcoidosis Successfully Treated with Rituximab and Mycophenolate Mofetil.

    PubMed

    Green, Sarah; Partridge, Erica; Idedevbo, Edore; Borg, Anton

    2016-01-01

    Autoimmune haemolytic anaemia is not a well-recognised complication of sarcoidosis. We describe the case of a 30-year-old female who presented with acute warm haemolytic anaemia and widespread lymphadenopathy. Sarcoidosis was diagnosed on lymph node biopsy and further investigation. The haemolytic anaemia responded only to a high dose of steroids. Evidence regarding treatment of steroid refractory autoimmune haemolysis secondary to sarcoidosis is lacking. Based on the emergent evidence that both disorders share common immunopathogenic mechanisms involving Th1 and Th17 lymphocytes, our patient was given rituximab and mycophenolate mofetil to successfully suppress the haemolysis and sarcoid activity. PMID:27563474

  3. Steroid Refractory Autoimmune Haemolytic Anaemia Secondary to Sarcoidosis Successfully Treated with Rituximab and Mycophenolate Mofetil

    PubMed Central

    Idedevbo, Edore; Borg, Anton

    2016-01-01

    Autoimmune haemolytic anaemia is not a well-recognised complication of sarcoidosis. We describe the case of a 30-year-old female who presented with acute warm haemolytic anaemia and widespread lymphadenopathy. Sarcoidosis was diagnosed on lymph node biopsy and further investigation. The haemolytic anaemia responded only to a high dose of steroids. Evidence regarding treatment of steroid refractory autoimmune haemolysis secondary to sarcoidosis is lacking. Based on the emergent evidence that both disorders share common immunopathogenic mechanisms involving Th1 and Th17 lymphocytes, our patient was given rituximab and mycophenolate mofetil to successfully suppress the haemolysis and sarcoid activity. PMID:27563474

  4. Activity and safety of combined rituximab with chlorambucil in patients with mantle cell lymphoma.

    PubMed

    Bauwens, Deborah; Maerevoet, Marie; Michaux, Lucienne; Théate, Ivan; Hagemeijer, Anne; Stul, Michel; Danse, Etienne; Costantini, Sabrina; Vannuffel, Pascal; Straetmans, Nicole; Vekemans, Marie-Christiane; Deneys, Véronique; Ferrant, Augustin; Van Den Neste, Eric

    2005-11-01

    We evaluated the combination of rituximab with chlorambucil in patients with mantle cell lymphoma (MCL) not eligible for aggressive therapy. Fourteen patients (male/female: 9/5) were included (two newly diagnosed, 12 relapsed/refractory). The toxicities were neutropenia, thrombopenia and infection. Nine (64%) patients responded; five (36%) achieved complete remission and four (29%) achieved partial remission. The median progression-free survival for responders was 26 months (95% CI, 4-48). Marrow polymerase chain reaction negativity was attained in seven responders. These results suggest that this schedule may have notable antitumour activity in patients with MCL, including patients in relapse after autologous stem cell transplantation. PMID:16225653

  5. Consensus statement on the use of rituximab in patients with rheumatoid arthritis

    PubMed Central

    Smolen, J S; Keystone, E C; Emery, P; Breedveld, F C; Betteridge, N; Burmester, G R; Dougados, M; Ferraccioli, G; Jaeger, U; Klareskog, L; Kvien, T K; Martin‐Mola, E; Pavelka, K

    2007-01-01

    A large number of experts experienced in the treatment of rheumatoid arthritis were involved in formulating a consensus statement on the use of B cell‐targeted treatment with rituximab in patients with rheumatoid arthritis. The statement was supported by data from randomised controlled clinical trials and the substantial literature on oncology. The statement underwent three rounds of discussions until its ultimate formulation. It should guide clinicians in the use of this newly approved biological agent in treating patients with rheumatoid arthritis. PMID:17068064

  6. Subcutaneous immunoglobulin in lymphoproliferative disorders and rituximab-related secondary hypogammaglobulinemia: a single-center experience in 61 patients

    PubMed Central

    Compagno, Nicolò; Cinetto, Francesco; Semenzato, Gianpietro; Agostini, Carlo

    2014-01-01

    Intravenous immunoglobulin replacement therapy represents the standard treatment for hypogammaglobulinemia secondary to B-cell lymphoproliferative disorders. Subcutaneous immunoglobulin infusion is an effective, safe and well-tolerated treatment approach in primary immunodeficiencies but no extensive data are available on their use in secondary hypogammaglobulinemia, a frequent phenomenon occurring after treatment with anti-CD20 monoclonal antibodies in lymphoproliferative disorders. In this retrospective study we evaluated efficacy (serum IgG trough levels, incidence of infections per year, need for antibiotics) and safety (number of adverse events) of intravenous (300 mg/kg/4 weeks) versus subcutaneous (75 mg/kg/week) immunoglobulin replacement therapy in 61 patients. In addition, the impact of the infusion methods on quality of life was compared. All patients were treated with subcutaneous immunoglobulin, and 33 out of them had been previously treated with intravenous immunoglobulin. Both treatments appeared to be effective in replacing Ig production deficiency and in reducing the incidence of infectious events and the need for antibiotics. Subcutaneous immunoglobulin obtained a superior benefit when compared to intravenous immunoglobulin achieving higher IgG trough levels, lower incidence of overall infection and need for antibiotics. The incidence of serious bacterial infections was similar with both infusion ways. As expected, a lower number of adverse events was registered with subcutaneous immunoglobulin, compared to intravenous immunoglobulin, with no serious adverse events. Finally, we observed an improvement in health-related quality of life parameters after the switch to subcutaneous immunoglobulin. Our results suggest that subcutaneous immunoglobulin is safe and effective in patients with hypogammaglobulinemia associated to lymphoproliferative disorders. PMID:24682509

  7. Chimeric Antigen Receptor T Cells for Sustained Remissions in Leukemia

    PubMed Central

    Maude, Shannon L.; Frey, Noelle; Shaw, Pamela A.; Aplenc, Richard; Barrett, David M.; Bunin, Nancy J.; Chew, Anne; Gonzalez, Vanessa E.; Zheng, Zhaohui; Lacey, Simon F.; Mahnke, Yolanda D.; Melenhorst, Jan J.; Rheingold, Susan R.; Shen, Angela; Teachey, David T.; Levine, Bruce L.; June, Carl H.; Porter, David L.; Grupp, Stephan A.

    2014-01-01

    BACKGROUND Relapsed acute lymphoblastic leukemia (ALL) is difficult to treat despite the availability of aggressive therapies. Chimeric antigen receptor–modified T cells targeting CD19 may overcome many limitations of conventional therapies and induce remission in patients with refractory disease. METHODS We infused autologous T cells transduced with a CD19-directed chimeric antigen receptor (CTL019) lentiviral vector in patients with relapsed or refractory ALL at doses of 0.76×106 to 20.6×106 CTL019 cells per kilogram of body weight. Patients were monitored for a response, toxic effects, and the expansion and persistence of circulating CTL019 T cells. RESULTS A total of 30 children and adults received CTL019. Complete remission was achieved in 27 patients (90%), including 2 patients with blinatumomab-refractory disease and 15 who had undergone stem-cell transplantation. CTL019 cells proliferated in vivo and were detectable in the blood, bone marrow, and cerebrospinal fluid of patients who had a response. Sustained remission was achieved with a 6-month event-free survival rate of 67% (95% confidence interval [CI], 51 to 88) and an overall survival rate of 78% (95% CI, 65 to 95). At 6 months, the probability that a patient would have persistence of CTL019 was 68% (95% CI, 50 to 92) and the probability that a patient would have relapse-free B-cell aplasia was 73% (95% CI, 57 to 94). All the patients had the cytokine-release syndrome. Severe cytokine-release syndrome, which developed in 27% of the patients, was associated with a higher disease burden before infusion and was effectively treated with the anti–interleukin-6 receptor antibody tocilizumab. CONCLUSIONS Chimeric antigen receptor–modified T-cell therapy against CD19 was effective in treating relapsed and refractory ALL. CTL019 was associated with a high remission rate, even among patients for whom stem-cell transplantation had failed, and durable remissions up to 24 months were observed. (Funded by

  8. Perspectives of ofatumumab as CD20 targeted therapy in rheumatoid arthritis and other autoimmune diseases.

    PubMed

    Pers, Yves Marie; Jorgensen, Christian

    2016-09-01

    Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune condition viewed as a severe destructive disease. The treatment strategies include anti-CD20 monoclonal antibody (mAb)-targeting B cells. Ofatumumab specifically targets a membrane-proximal epitope on the CD20 molecule distinct from other anti-CD20 antibodies including rituximab and ocrelizumab, and bind the epitope located on the large loop of CD20. This explains a more durable B-cell depletion and a different pharmacodynamic. We review the pharmacodynamic of B-cell depletion and analyze the results in RA and other B-cell-mediated autoimmune diseases. The randomized trial in RA showed clinical efficacy comparable to rituximab at week 24. However, structural impact has not been demonstrated. Studies including RA patients refractory to rituximab would be useful to define the optimal strategy of ofatumumab therapy. PMID:27485081

  9. How Chimeric Antigen Receptor Design Affects Adoptive T Cell Therapy.

    PubMed

    Gacerez, Albert T; Arellano, Benjamine; Sentman, Charles L

    2016-12-01

    Chimeric antigen receptor (CAR) T cells have been developed to treat tumors and have shown great success against B cell malignancies. Exploiting modular designs and swappable domains, CARs can target an array of cell surface antigens and, upon receptor-ligand interactions, direct signaling cascades, thereby driving T cell effector functions. CARs have been designed using receptors, ligands, or scFv binding domains. Different regions of a CAR have each been found to play a role in determining the overall efficacy of CAR T cells. Therefore, this review provides an overview of CAR construction and common designs. Each CAR region is discussed in the context of its importance to a CAR's function. Additionally, the review explores how various engineering strategies have been applied to CAR T cells in order to regulate CAR T cell function and activity. J. Cell. Physiol. 231: 2590-2598, 2016. © 2016 Wiley Periodicals, Inc. PMID:27163336

  10. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy

    PubMed Central

    Dai, Hanren; Wang, Yao; Lu, Xuechun

    2016-01-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy. PMID:26819347

  11. The pharmacology of second-generation chimeric antigen receptors.

    PubMed

    van der Stegen, Sjoukje J C; Hamieh, Mohamad; Sadelain, Michel

    2015-07-01

    Second-generation chimeric antigen receptors (CARs) retarget and reprogramme T cells to augment their antitumour efficacy. The combined activating and co-stimulatory domains incorporated in these CARs critically determine the function, differentiation, metabolism and persistence of engineered T cells. CD19-targeted CARs that incorporate CD28 or 4-1BB signalling domains are the best known to date. Both have shown remarkable complete remission rates in patients with refractory B cell malignancies. Recent data indicate that CD28-based CARs direct a brisk proliferative response and boost effector functions, whereas 4-1BB-based CARs induce a more progressive T cell accumulation that may compensate for less immediate potency. These distinct kinetic features can be exploited to further develop CAR-based T cell therapies for a variety of cancers. A new field of immunopharmacology is emerging. PMID:26129802

  12. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy.

    PubMed

    Dai, Hanren; Wang, Yao; Lu, Xuechun; Han, Weidong

    2016-07-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy. PMID:26819347

  13. Chimeric Antigen Receptors Modified T-Cells for Cancer Therapy

    PubMed Central

    Dai, Hanren; Wang, Yao; Lu, Xuechun

    2016-01-01

    The genetic modification and characterization of T-cells with chimeric antigen receptors (CARs) allow functionally distinct T-cell subsets to recognize specific tumor cells. The incorporation of costimulatory molecules or cytokines can enable engineered T-cells to eliminate tumor cells. CARs are generated by fusing the antigen-binding region of a monoclonal antibody (mAb) or other ligand to membrane-spanning and intracellular-signaling domains. They have recently shown clinical benefit in patients treated with CD19-directed autologous T-cells. Recent successes suggest that the modification of T-cells with CARs could be a powerful approach for developing safe and effective cancer therapeutics. Here, we briefly review early studies, consider strategies to improve the therapeutic potential and safety, and discuss the challenges and future prospects for CAR T-cells in cancer therapy.

  14. Chimeric Antigen Receptor T Cell Therapy in Hematology

    PubMed Central

    Ataca, Pınar; Arslan, Önder

    2015-01-01

    It is well demonstrated that the immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation. Adoptive T cell transfer has been improved to be more specific and potent and to cause less off-target toxicity. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR) and chimeric antigen receptor (CAR) modified T cells. On 1 July 2014, the United States Food and Drug Administration granted ‘breakthrough therapy’ designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the benefits of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical and clinical studies, and the effectiveness and drawbacks of this strategy. PMID:26377367

  15. Chimeric Antigen Receptor T Cell Therapy in Hematology.

    PubMed

    Ataca, Pınar; Arslan, Önder

    2015-12-01

    It is well demonstrated that the immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation. Adoptive T cell transfer has been improved to be more specific and potent and to cause less off-target toxicity. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR) and chimeric antigen receptor (CAR) modified T cells. On 1 July 2014, the United States Food and Drug Administration granted 'breakthrough therapy' designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the benefits of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical and clinical studies, and the effectiveness and drawbacks of this strategy. PMID:26377367

  16. Lymphomatoid granulomatosis treated successfully with rituximab in a renal transplant patient.

    PubMed

    Castrale, Cindy; El Haggan, Wael; Chapon, Françoise; Reman, Oumedaly; Lobbedez, Thierry; Ryckelynck, Jean Philippe; Hurault de Ligny, Bruno

    2011-01-01

    Lymphomatoid granulomatosis (LYG) in renal transplant recipients is rare multisystemic angiocentric lymphoproliferative disorder with significant malignant potential. Here, we describe LYG in a 70-year-old renal allograft recipient who, 4 years after transplantation, on tacrolimus and mycophenolate mofetil and prednisone maintenance immunosuppression, complained of low-grade fever, persistent headache and gait disturbance. The MRI of the brain revealed diffuse periventricular cerebral and cerebellar contrast-enhanced lesions. The CT scan of the thorax showed multiple pulmonary nodular opacities in both lung fields. The patient was diagnosed LYG based on the cerebral biopsy showing perivascular infiltration of CD20-positive B-lymphocytes with granulomatous lesions and immunofluorescence staining with anti-EBV antibodies. With careful reduction of the immunossuppression combined with the use of rituximab, our patient showed a complete disappearance of LYG, and she is clinically well more than 4 years after the diagnosis, with good kidney function. No recurrence has been observed by radiological imaging until now. This is the first report of a durable (>4 years) complete remission of LYG after treatment with rituximab in renal transplantation. PMID:21559262

  17. Rituximab plus liposomal doxorubicin in HIV-infected patients with KSHV-associated multicentric Castleman disease.

    PubMed

    Uldrick, Thomas S; Polizzotto, Mark N; Aleman, Karen; Wyvill, Kathleen M; Marshall, Vickie; Whitby, Denise; Wang, Victoria; Pittaluga, Stefania; O'Mahony, Deirdre; Steinberg, Seth M; Little, Richard F; Yarchoan, Robert

    2014-12-01

    Kaposi sarcoma (KS) herpesvirus-associated multicentric Castleman disease (KSHV-MCD) is a lymphoproliferative disorder, most commonly seen in HIV-infected patients, that has a high mortality if untreated. Concurrent KS is common. Although rituximab has reported activity in KSHV-MCD, its use is often associated with KS progression. Within a natural history study of KSHV-MCD, we prospectively evaluated rituximab 375 mg/m(2) combined with liposomal doxorubicin 20 mg/m(2) (R-Dox) every 3 weeks in 17 patients. Patients received a median of 4 cycles (range 3-9). All received antiretroviral therapy, 11 received consolidation interferon-α, and 6 received consolidation high-dose zidovudine with valganciclovir. Using NCI KSHV-MCD response criteria, major clinical and biochemical responses were attained in 94% and 88% of patients, respectively. With a median 58 months' potential follow-up, 3-year event-free survival was 69% and 3-year overall survival was 81%. During R-Dox therapy, cutaneous KS developed in 1 patient, whereas 5 of 6 patients with it had clinical improvement. R-Dox was associated with significant improvement in anemia and hypoalbuminemia. KSHV viral load, KSHV viral interleukin-6, C-reactive protein, human interleukin-6, and serum immunoglobulin free light chains decreased with therapy. R-Dox is effective in symptomatic KSHV-MCD and may be useful in patients with concurrent KS. This trial was registered at www.clinicaltrials.gov as #NCT00092222. PMID:25331113

  18. Rituximab in the treatment of diffuse large B-cell lymphoma primary of the lung.

    PubMed

    Aviles, Agustin; Nambo, Maria J; Huerta-Guzman, Judith; Silva, Luis; Neri, Natividad

    2013-03-01

    Diffuse large B-cell lymphoma primary of lung (DLBCL-PL) is a rare presentation of extranodal lymphoma, in most cases chemotherapy-based anthracyclines: CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) has been the treatment, with excellent outcome. The addition of rituximab to CHOP (R-CHOP) has been considered the gold standard in the treatment of nodal DLBCL. Thus, we assess in a large number of cases of DLBCL-PL whether the use of R-CHOP could improve survival in this setting of patients. Forty-two patients with DLBCL-PL, stage IE, age 65 years or younger, were treated with standard R-CHOP, no consolidation radiotherapy or maintenance therapy were considered. They were matched with patients who received CHOP alone to assess efficacy and toxicity. Complete response was observed in 35 patients (83%), and 7 patients were considered failure (16%). The study has a median follow-up of 42.8 months. Actuarial curves at 5 years showed that progression-free survival was 88 % and overall survival was 70 %. The results were not statistically different when compared retrospectively with patients who received CHOP alone. Treatment was well tolerated. The addition of rituximab to chemotherapy did not improve outcome in patients with DLBCL-PL. PMID:23394581

  19. Newcastle disease virus, rituximab, and doxorubicin combination as anti-hematological malignancy therapy

    PubMed Central

    Al-Shammari, Ahmed Majeed; Rameez, Huda; Al-Taee, Maha F

    2016-01-01

    Hematological malignancies are important diseases that need more powerful therapeutics. Even with current targeting therapies, such as rituximab and other chemotherapeutic agents, there is a need to develop new treatment strategies. Combination therapy seems the best option to target the tumor cells by different mechanisms. Virotherapy is a very promising treatment modality, as it is selective, safe, and causes cancer destruction. The Iraqi strain of Newcastle disease virus (NDV) has proved to be effective both in vitro and in vivo. In the current work, we tested its ability on anti-hematological tumors and enhanced current treatments with combination therapy, and studied this combination using Chou–Talalay analysis. p53 concentration was measured to evaluate the mechanism of this proposed synergism. The results showed that NDV was synergistic with doxorubicin in low doses on plasmacytoma cells, with no involvement of p53 pathways, but involved p53 when the combination was used on non-Hodgkin lymphoma cells. NDV in combination with rituximab showed enhanced cytotoxicity that was p53-independent. In conclusion, this work proposes a novel combination modality for treatment of some hematological malignancies. PMID:27579294

  20. Outcomes 5 years after response to rituximab therapy in children and adults with immune thrombocytopenia

    PubMed Central

    Mahévas, Matthieu; Lee, Soo Y.; Stasi, Roberto; Cunningham-Rundles, Susanna; Godeau, Bertrand; Kanter, Julie; Neufeld, Ellis; Taube, Tillmann; Ramenghi, Ugo; Shenoy, Shalini; Ward, Mary J.; Mihatov, Nino; Patel, Vinay L.; Bierling, Philippe; Lesser, Martin; Cooper, Nichola; Bussel, James B.

    2012-01-01

    Treatments for immune thrombocytopenic purpura (ITP) providing durable platelet responses without continued dosing are limited. Whereas complete responses (CRs) to B-cell depletion in ITP usually last for 1 year in adults, partial responses (PRs) are less durable. Comparable data do not exist for children and 5-year outcomes are unavailable. Patients with ITP treated with rituximab who achieved CRs and PRs (platelets > 150 × 109/L or 50-150 × 109/L, respectively) were selected to be assessed for duration of their response; 72 adults whose response lasted at least 1 year and 66 children with response of any duration were included. Patients had baseline platelet counts < 30 × 109/L; 95% had ITP of > 6 months in duration. Adults and children each had initial overall response rates of 57% and similar 5-year estimates of persisting response (21% and 26%, respectively). Children did not relapse after 2 years from initial treatment whereas adults did. Initial CR and prolonged B-cell depletion predicted sustained responses whereas prior splenectomy, age, sex, and duration of ITP did not. No novel or substantial long-term clinical toxicity was observed. In summary, 21% to 26% of adults and children with chronic ITP treated with standard-dose rituximab maintained a treatment-free response for at least 5 years without major toxicity. These results can inform clinical decision-making. PMID:22566601

  1. Newcastle disease virus, rituximab, and doxorubicin combination as anti-hematological malignancy therapy.

    PubMed

    Al-Shammari, Ahmed Majeed; Rameez, Huda; Al-Taee, Maha F

    2016-01-01

    Hematological malignancies are important diseases that need more powerful therapeutics. Even with current targeting therapies, such as rituximab and other chemotherapeutic agents, there is a need to develop new treatment strategies. Combination therapy seems the best option to target the tumor cells by different mechanisms. Virotherapy is a very promising treatment modality, as it is selective, safe, and causes cancer destruction. The Iraqi strain of Newcastle disease virus (NDV) has proved to be effective both in vitro and in vivo. In the current work, we tested its ability on anti-hematological tumors and enhanced current treatments with combination therapy, and studied this combination using Chou-Talalay analysis. p53 concentration was measured to evaluate the mechanism of this proposed synergism. The results showed that NDV was synergistic with doxorubicin in low doses on plasmacytoma cells, with no involvement of p53 pathways, but involved p53 when the combination was used on non-Hodgkin lymphoma cells. NDV in combination with rituximab showed enhanced cytotoxicity that was p53-independent. In conclusion, this work proposes a novel combination modality for treatment of some hematological malignancies. PMID:27579294

  2. Rituximab for refractory subcutaneous Sweet's syndrome in chronic lymphocytic leukemia: A case report

    PubMed Central

    HASHEMI, SEYED MEHDI; FAZELI, SEYED AMIRHOSSEIN; VAHEDI, ABDOLBASET; GOLABCHIFARD, REZA

    2016-01-01

    Sweet's syndrome is a neutrophilic dermatosis characterised by sudden onset of fever, neutrophilia, erythematous skin rashes and neutrophilic infiltration of the dermis. Subcutaneous Sweet's syndrome, or Sweet's panniculitis, is an uncommon variant of the classic syndrome, with hypodermal neutrophilic infiltration. The association of Sweet's syndrome with various malignancies has been reported. The most common underlying hematological malignancies are of myeloid origin; however, there have been several reports of the classic Sweet's syndrome in patients with a lymphoproliferative disorder, although the association of subcutaneous Sweet's syndrome with lymphoproliferative disorders has not been well-documented thus far. Herein, we present the case of a 48-year-old man with a 2-year history of chronic lymphocytic leukemia who developed fever and skin rashes, without any evidence of a relapse. The clinical and pathological investigation resulted in the diagnosis of subcutaneous Sweet's syndrome. The patient exhibited no significant response to conventional therapeutic measures; however, following two subsequent doses of rituximab, his general condition and skin rash improved. The follow-up skin biopsy demonstrated dermal neutrophilic infiltrations in conjunction with prior mixed lobular and septal panniculitis, suggesting evolution of subcutaneous Sweet's syndrome to its classic form. To the best of our knowledge, this is one of the first reports of rituximab as a novel biological treatment for Sweet's syndrome. However, further randomized trials are required to evaluate the efficacy and safety of such biological therapies for Sweet's syndrome. PMID:26998300

  3. Chimeric conundra: are nucleomorphs and chromists monophyletic or polyphyletic?

    PubMed Central

    Cavalier-Smith, T; Allsopp, M T; Chao, E E

    1994-01-01

    All algae with chloroplasts located not freely in the cytosol, but inside two extra membranes, probably arose chimerically by the permanent fusion of two different eukaryote cells: a protozoan host and a eukaryotic algal symbiont. Two such groups, cryptomonads (phylum Cryptista) and Chlorarachniophyta, still retain a DNA-containing relic of the nucleus of the algal endosymbiont, known as the nucleomorph, as well as the host nucleus. These two phyla were traditionally assumed to have obtained their chloroplasts separately by two independent symbioses. We have sequenced the nuclear and the nucleomorph 18S rRNA genes of the nonphotosynthetic cryptomonad Chilomonas paramecium. Our phylogenetic analysis suggests that cryptomonad and chlorarachniophyte nucleomorphs may be related to each other and raises the possibility that both phyla may have diverged from a common ancestral chimeric cell that originated by a single endosymbiosis involving an algal endosymbiont related to the ancestor of red algae. But, because of the instability of the molecular trees when different taxa are added, there is insufficient evidence to overturn the traditional view that Chlorarachnion nucleomorphs evolved separately from a relative of green algae. The four phyla that contain chromophyte algae (those with chlorophyll c--i.e., Cryptista, Heterokonta, Haptophyta, Dinozoa) are distantly related to each other and to Chlorarachniophyta on our trees. However, all of the photosynthetic taxa within each of these four phyla radiate from each other very substantially after the radiation of the four phyla themselves. This favors the view that the common ancestor of these four phyla was not photosynthetic and that chloroplasts were implanted separately into each much more recently. This probable polyphyly of the chromophyte algae, if confirmed, would make it desirable to treat Cryptista, Heterokonta, and Haptophyta as separate kingdoms, rather than to group them together in the single kingdom

  4. Chimeric elk/mouse prion proteins in transgenic mice

    PubMed Central

    Tamgüney, Gültekin; Giles, Kurt; Oehler, Abby; Johnson, Natrina L.; DeArmond, Stephen J.

    2013-01-01

    Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). Between codons 169 and 219, six residues distinguish ElkPrP from MoPrP: N169S, T173N, V183I, I202V, I214V and R219K. Using chimeric elk/mouse PrP constructs, we generated 12 Tg mouse lines and determined incubation times after intracerebral inoculation with the mouse-passaged RML scrapie or Elk1P CWD prions. Unexpectedly, one Tg mouse line expressing Elk3M(SNIVVK) exhibited incubation times of <70 days when inoculated with RML prions; a second line had incubation times of <90 days. In contrast, mice expressing full-length ElkPrP had incubation periods of >250 days for RML prions. Tg(Elk3M,SNIVVK) mice were less susceptible to CWD prions than Tg(ElkPrP) mice. Changing three C-terminal mouse residues (202, 214 and 219) to those of elk doubled the incubation time for mouse RML prions and rendered the mice resistant to Elk1P CWD prions. Mutating an additional two residues from mouse to elk at codons 169 and 173 increased the incubation times for mouse prions to >300 days, but made the mice susceptible to CWD prions. Our findings highlight the role of C-terminal residues in PrP that control the susceptibility and replication of prions. PMID:23100369

  5. MRI assessment of suppression of structural damage in patients with rheumatoid arthritis receiving rituximab: results from the randomised, placebo-controlled, double-blind RA-SCORE study

    PubMed Central

    Peterfy, Charles; Emery, Paul; Tak, Paul P; Østergaard, Mikkel; DiCarlo, Julie; Otsa, Kati; Navarro Sarabia, Federico; Pavelka, Karel; Bagnard, Marie-Agnes; Gylvin, Lykke Hinsch; Bernasconi, Corrado; Gabriele, Annarita

    2016-01-01

    Objective To evaluate changes in structural damage and joint inflammation assessed by MRI following rituximab treatment in a Phase 3 study of patients with active rheumatoid arthritis (RA) despite methotrexate (MTX) who were naive to biological therapy. Methods Patients were randomised to receive two infusions of placebo (n=63), rituximab 500 mg (n=62), or rituximab 1000 mg (n=60) intravenously on days 1 and 15. MRI scans and radiographs of the most inflamed hand and wrist were acquired at baseline, weeks 12 (MRI only), 24 and 52. The primary end point was the change in MRI erosion score from baseline at week 24. Results Patients treated with rituximab demonstrated significantly less progression in the mean MRI erosion score compared with those treated with placebo at weeks 24 (0.47, 0.18 and 1.60, respectively, p=0.003 and p=0.001 for the two rituximab doses vs placebo) and 52 (−0.30, 0.11 and 3.02, respectively; p<0.001 and p<0.001). Cartilage loss at 52 weeks was significantly reduced in the rituximab group compared with the placebo group. Other secondary end points of synovitis and osteitis improved significantly with rituximab compared with placebo as early as 12 weeks and improved further at weeks 24 and 52. Conclusions This study demonstrated that rituximab significantly reduced erosion and cartilage loss at week 24 and week 52 in MTX-inadequate responder patients with active RA, suggesting that MRI is a valuable tool for assessing inflammatory and structural damage in patients with established RA receiving rituximab. Trial registration number NCT00578305 PMID:25355728

  6. High response rate and durable remissions following fludarabine and rituximab combination therapy for chronic cold agglutinin disease.

    PubMed

    Berentsen, Sigbjørn; Randen, Ulla; Vågan, Anne Marita; Hjorth-Hansen, Henrik; Vik, Anders; Dalgaard, Jakob; Jacobsen, Eva-Marie; Thoresen, Aud S; Beiske, Klaus; Tjønnfjord, Geir E

    2010-10-28

    Most patients diagnosed with primary chronic cold agglutinin disease (CAD) have a clonal lymphoproliferative bone marrow disorder. Treatment with rituximab is the only well-documented effective therapy, leading to 45%-60% partial responses (PR). Complete responses (CR) are rare, and median response duration is only 11 months. In a prospective multicenter trial, 29 patients received rituximab 375 mg/m(2) on days 1, 29, 57 and 85; and fludarabine orally, 40 mg/m(2) on days 1-5, 29-34, 57-61 and 85-89. Twenty-two patients (76%) responded, 6 (21%) achieving CR and 16 (55%) PR. Among 10 patients nonresponsive to rituximab monotherapy, 1 achieved CR and 6 PR. Median increase in hemoglobin level was 3.1 g/dL among the responders and 4.0 g/dL in those who achieved CR. Lower quartile of response duration was not reached after 33 months. Estimated median response duration was more than 66 months. Grade 3-4 hematologic toxicity occurred in 12 patients (41%). In conclusion, fludarabine and rituximab combination therapy is very efficient in patients with CAD. Toxicity may be a concern, and benefits should be carefully weighed against risks in very old and comorbid patients. It remains to be established whether the combination should be first-line or an efficient second-line therapy in CAD patients requiring treatment. PMID:20634373

  7. Plitidepsin (Aplidin) is a potent inhibitor of diffuse large cell and Burkitt lymphoma and is synergistic with rituximab.

    PubMed

    Barboza, Nora M; Medina, Daniel J; Budak-Alpdogan, Tulin; Aracil, Miguel; Jimeno, José M; Bertino, Joseph R; Banerjee, Debabrata

    2012-01-15

    Plitidepsin (Aplidin), an antitumor agent of marine origin, presently is undergoing phase II/III clinical trials, and has shown promise for the treatment of lymphoma. Here, we describe the antitumor effects of plitidepsin alone and in combination with rituximab and investigated the effects of each drug and the combination on the cell cycle and mechanism of cell death. Several Diffuse Large Cell Lymphoma (DLCL) lines and Burkitt cell lines were tested for sensitivity to plitidepsin and rituximab. All DLCL and Burkitt lymphoma cell lines were inhibited by plitidepsin in nanomolar concentrations, while rituximab sensitivity varied among different cell lines. Ramos and the RL cell lines proved sensitive to rituximab and were used to test the effects of each of the two drugs. The two agents exhibited synergism at all tested concentrations. For in vivo studies, irradiated athymic nude mice were engrafted with the Ramos lymphoma. Treatment was initiated when the tumors were ~0.5 cm in diameter, and toxic and therapeutic effects were monitored. In the in vivo study, additive effects of the combined two drugs, was demonstrated without an increase in host toxicity. The in vitro synergy and the in vivo additive antitumor effects without an increase in host toxicity with two relatively non-marrow suppressive agents encourages further development of this combination for treatment of aggressive B-cell lymphomas. PMID:22336911

  8. Navitoclax (ABT-263) and bendamustine ± rituximab induce enhanced killing of non-Hodgkin's lymphoma tumours in vivo

    PubMed Central

    Ackler, S; Mitten, MJ; Chen, J; Clarin, J; Foster, K; Jin, S; Phillips, DC; Schlessinger, S; Wang, B; Leverson, JD; Boghaert, ER

    2012-01-01

    BACKGROUND AND PURPOSE Bendamustine with or without rituximab provides an effective and more tolerable alternative to the polytherapy cyclophosphamide–doxorubicin–vincristine–prednisolone (CHOP) in the treatment of haematological tumours and is currently approved for the treatment of many haematological malignancies. Navitoclax (ABT-263) is a potent inhibitor of Bcl-2, Bcl-xL and Bcl-w, which has demonstrated efficacy in haematological tumours alone and in combination with other agents. This paper describes the in vivo efficacy of combining either bendamustine or bendamustine plus rituximab (BR) with navitoclax in xenograft models of non-Hodgkin's lymphoma EXPERIMENTAL APPROACH Activity was tested in xenograft models of diffuse large B-cell lymphoma (DoHH-2, SuDHL-4), mantle cell lymphoma (Granta 519) and Burkitt's lymphoma (RAMOS). Activity was also monitored in a systemic model of Granta 519. KEY RESULTS Navitoclax potentiated bendamustine activity in all cell lines tested. Bendamustine activated p53 in Granta 519 tumours, concurrent with activation of caspase 3. Navitoclax also improved responses to bendamustine-rituximab (BR) in a subset of tumours. CONCLUSIONS AND IMPLICATIONS Navitoclax in combination with bendamustine and BR is a viable combination strategy for use in the clinic and demonstrated superior efficacy compared with previously reported data for navitoclax plus CHOP and rituximab-CHOP. PMID:22624727

  9. A phase II trial of extended induction epratuzumab and rituximab for previously untreated follicular lymphoma: CALGB 50701

    PubMed Central

    Grant, Barbara W.; Jung, Sin-Ho; Johnson, Jeffrey L.; Kostakoglu, Lale; His, Eric; Byrd, John C.; Jones, Jeffrey; Leonard, John P.; Martin, S. Eric; Cheson, Bruce D.

    2013-01-01

    Rituximab combined with chemotherapy has improved the survival of previously untreated patients with follicular lymphoma (FL). Nevertheless, many patients neither want nor can tolerate chemotherapy, leading to interest in biological approaches. Epratuzumab is a humanized anti-CD22 monoclonal antibody with efficacy in relapsed FL. Since both rituximab and epratuzumab have single agent activity in FL, we evaluated the antibody combination as initial treatment of patients with FL. Patients and Methods Fifty-nine untreated patients with FL received epratuzumab 360 mg/m2 with rituximab 375 mg/m2 weekly for four induction doses. This combination was continued as extended induction in weeks 12, 20, 28, and 36. Response assessed by CT was correlated with clinical risk factors, FDG-PET findings at week 3, Fcg polymorphisms, immunohistochemical markers, and statin use. Results Therapy was well-tolerated with toxicities similar to expected with rituximab monotherapy. Fifty-two (88.2%) evaluable patients responded, including 25 complete responses (CR)(42.4%), and 27 partial responses (45.8%). At 3 years follow-up, 60% of patients remain in remission. Follicular Lymphoma International Prognostic Index (FLIPI) risk strongly predicted progression-free survival (p=0.022). Conclusions The high response rate and prolonged time to progression observed with this antibody combination are comparable to those observed after standard chemo-immunotherapies and further support the development of biologic, non-chemotherapeutic approaches for these patients. PMID:23922187

  10. Paraneoplastic pemphigus and myasthenia gravis, associated with inflammatory pseudotumor-like follicular dendritic cell sarcoma: response to rituximab.

    PubMed

    Wang, Lifang; Deng, Hui; Mao, Mei

    2016-08-01

    Paraneoplastic pemphigus (PNP) is an autoimmune blistering disease associated with neoplasms. The disease is most commonly of lymphoproliferative origin and presents high mortality. We describe a patient with PNP and myasthenia gravis associated with inflammatory pseudotumor-like follicular dendritic cell sarcoma, as well as the response to rituximab. PMID:27525088

  11. ChiTaRS 2.1--an improved database of the chimeric transcripts and RNA-seq data with novel sense-antisense chimeric RNA transcripts.

    PubMed

    Frenkel-Morgenstern, Milana; Gorohovski, Alessandro; Vucenovic, Dunja; Maestre, Lorena; Valencia, Alfonso

    2015-01-01

    Chimeric RNAs that comprise two or more different transcripts have been identified in many cancers and among the Expressed Sequence Tags (ESTs) isolated from different organisms; they might represent functional proteins and produce different disease phenotypes. The ChiTaRS 2.1 database of chimeric transcripts and RNA-Seq data (http://chitars.bioinfo.cnio.es/) is the second version of the ChiTaRS database and includes improvements in content and functionality. Chimeras from eight organisms have been collated including novel sense-antisense (SAS) chimeras resulting from the slippage of the sense and anti-sense intragenic regions. The new database version collects more than 29,000 chimeric transcripts and indicates the expression and tissue specificity for 333 entries confirmed by RNA-seq reads mapping the chimeric junction sites. User interface allows for rapid and easy analysis of evolutionary conservation of fusions, literature references and experimental data supporting fusions in different organisms. More than 1428 cancer breakpoints have been automatically collected from public databases and manually verified to identify their correct cross-references, genomic sequences and junction sites. As a result, the ChiTaRS 2.1 collection of chimeras from eight organisms and human cancer breakpoints extends our understanding of the evolution of chimeric transcripts in eukaryotes as well as their functional role in carcinogenic processes. PMID:25414346

  12. [Rituximab therapy in the treatment of anti-neutrophil cytoplasmic antibody (ANCA) -positive interstitial pneumonia: case report].

    PubMed

    Miyaoka, Tokiko; Itabashi, Mitsuyo; Kumon, Saeko; Akiyama, Kenichi; Iwabuchi, Yuko; Kataoka, Hiroshi; Moriyama, Takahito; Takei, Takashi; Nitta, Kosaku

    2016-01-01

    We report a patient treated with rituximab for interstitial pneumonia (IP) associated with microscopic polyangiitis (MPA) and who was undergoing hemodialysis. A 59-year-old woman who had been treated with tacrolimus for 1 year for rheumatic arthritis was referred to the Department of Nephrology for fatigue, fever, weight loss, and rapidly developing renal dysfunction. On the first admission, severe renal dysfunction, proteinuria, hematuria, and an elevated titer of MPO-ANCA were observed, and the woman was diagnosed with rapidly progressive glomerulonephritis because of MPA. At that point, IP was found to be present but not active. Although steroid semipulse therapy following an initial prednisolone (PSL) administration of 40 mg/day, IVCY, and plasma exchange were administered, renal dysfunction did not recover, and the patient required maintenance hemodialysis. Upon discharge, a high titer of MPO-ANCA was continuously observed. Nine months after the initiation of hemodialysis, respiratory discomfort and desaturation developed. Interstitial shadow and ground glass opacity were seen on a CT scan, and the patient was diagnosed with exacerbation of interstitial pneumonia caused by MPA recurrence. At the second admission, acute findings identified by imaging techniques had improved. However, the high titer of MPO-ANCA continued in spite of the steroid semi-pulse therapy following PSL administration, and rituximab corresponding to 200 mg/weekly for 1 month was also administered. The dose of rituximab was decreased subsequently because the patient was judged to be compromised by the hemodialysis. At the same time, internal administration of sulfamethoxazole/trimethoprim was initiated. After the rituximab treatment, MPO-ANCA antibodies gradually decreased, and the respiratory condition improved. Five months after the rituximab treatment, respiratory dysfunction recurred. Based on the CT findings and a high level of β-D-glycan, the patient was diagnosed with ARDS due to

  13. Improvement in Gemcitabine-Induced Thrombotic Microangiopathy with Rituximab in a Patient with Ovarian Cancer: Mechanistic Considerations

    PubMed Central

    Murugapandian, Sangeetha; Bijin, Babitha; Mansour, Iyad; Daheshpour, Sepehr; Pillai, Biju G.; Thajudeen, Bijin; Salahudeen, Abdulla K.

    2015-01-01

    Gemcitabine is a potent and widely used anticancer drug. We report a case of gemcitabine-induced thrombotic microangiopathy (GCI-TMA), a known but not widely recognized complication of gemcitabine use, and our experience of treating GCI-TMA with rituximab. A 74-year-old woman was referred to our clinic for an evaluation of worsening renal function. She has recently been treated for ovarian cancer (diagnosed in 2011) with surgery (tumor debulking and bilateral salpingo-oophorectomy) along with cisplatin chemotherapy in 2012, followed by carboplatin/doxorubicin in 2013 and recent therapy for resistant disease with gemcitabine. Laboratory tests showed anemia, normal platelets and elevated lactate dehydrogenase. A peripheral smear revealed numerous schistocytes, and a kidney biopsy showed acute as well as chronic TMA. The patient continued on gemcitabine therapy, and treatment with plasma exchange was started. Since there was no response to treatment even after 5 sessions of plasma exchange, one dose of rituximab was given, which was associated with a drop in the creatinine level to 2 mg/dl. The pathogenesis of renal injury could be the effect of direct injury to the endothelium mediated by cytokines. Usual treatment includes withdrawing the drug and initiation of treatment with plasmapheresis with or without steroids. In cases resistant to plasmapheresis, treatment with rituximab can be tried. The mechanism of action of rituximab might be due to the reduced production of B-cell-dependent cytokines that drive endothelial dysfunction by depleting B cells. Patients receiving gemcitabine chemotherapy should be monitored for the development of TMA, and early treatment with plasma exchange along with rituximab might benefit these patients who already have a bad prognosis. PMID:26266248

  14. Assessment of flares in lupus patients enrolled in a phase II/III study of rituximab (EXPLORER).

    PubMed

    Merrill, Jt; Buyon, Jp; Furie, Ra; Latinis, Km; Gordon, C; Hsieh, H-J; Brunetta, P

    2011-06-01

    The EXPLORER study was designed to assess the response to rituximab versus placebo in patients with moderate to severe extrarenal systemic lupus erythematosus (SLE) receiving background immunosuppression. The definition of response required reduced clinical activity without subsequent flares over 52 weeks, and the study did not meet its efficacy endpoint. The current exploratory analysis assessed flare rates in patients who achieved initial low disease activity response (British Isles Lupus Assessment Group [BILAG] C or better in all organs) during the study. Exploratory reanalysis of data from the EXPLORER trial was conducted, considering alternative definitions for flare. No difference was found between rituximab and placebo in preventing or delaying moderate to severe flares. However, when severe (BILAG A) flares alone were examined, rituximab reduced the risk of a subsequent first A flare (hazard ratio = 0.61; p = 0.052) and lowered mean ± SD annualized A flare rates (0.86 ± 1.47 vs. 1.41 ± 2.14; p = 0.038). Eighty-four (49.7%) rituximab-treated patients achieved low disease activity without subsequent A flares versus 31 (35.2%) placebo-treated patients (p = 0.027). Prednisone rescue for A flares was similar in rituximab- (24%) and placebo-treated (14%) patients (p = 0.204). This post hoc analysis evaluates the hypothesis that assessment of BILAG A flares may distinguish potential treatment effects with greater sensitivity than assessment of BILAG B flares. PMID:21478286

  15. Diminishing prognostic role of preexisting diabetes mellitus for patients with diffuse large B-cell lymphoma in the rituximab era.

    PubMed

    Lu, Hsueh-Ju; Huang, Yu-Chung; Liu, Chun-Yu; Hung, Man-Hsin; Hu, Ming-Hung; Wu, Chia-Yun; Hong, Ying-Chung; Hsiao, Liang-Tsai; Gau, Jyh-Pyng; Liu, Jin-Hwang; Hsu, Hui-Chi; Chiou, Tzeon-Jye; Tzeng, Cheng-Hwai; Yu, Yuan-Bin

    2013-11-01

    Rituximab reforms the treatment of diffuse large B-cell lymphoma (DLBCL) and the prognostic significance of baseline patient features should be reevaluated. Few population-based studies have investigated the association of diabetes mellitus (DM) and outcomes of lymphoma; however, the results remain inconclusive. From January 1, 2000 to December 31, 2009, a total of 468 consecutive newly diagnosed DLBCL patients receiving first-line chemotherapy with cyclophosphamide, vincristine, doxorubicin, and prednisolone (CHOP) or rituximab plus CHOP (R-CHOP) were enrolled. Pre-existing DM was defined according to medical history, use of antidiabetic medications, or any record of an abnormal hemoglobin A1c test. Progression-free survival (PFS) and overall survival (OS) were estimated and compared using the Kaplan-Meier method with a log-rank test. CHOP was administered in 194 patients, and 274 patients received R-CHOP. DM was identified in 16.2 % (76/468) of patients. Diabetic patients were older and more performance restricted, compared to the non-DM patients in both the CHOP and R-CHOP groups. In the CHOP group, 5-year PFS and OS were inferior in DM patients (PFS, 32.4 vs. 50.0 % (P = 0.039); OS, 38.2 vs. 62.5 % (P = 0.002)). However, outcomes were similar for both DM and non-DM patients in the context of R-CHOP treatment (PFS, 69.0 vs. 57.3 % (P = 0.179); OS, 76.2 vs. 69.8 % (P = 0.586)). The response rate of chemotherapy in DM patients was also improved to a level similar to non-DM patients with rituximab use. In conclusion, the prognostic significance of preexisting DM in DLBCL patients is changing in the rituximab era. The potentially additional benefit of rituximab in DM patients merits further investigation. PMID:23712292

  16. A randomized phase II crossover study of imatinib or rituximab for cutaneous sclerosis after hematopoietic cell transplantation

    PubMed Central

    Arai, Sally; Pidala, Joseph; Pusic, Iskra; Chai, Xiaoyu; Jaglowski, Samantha; Khera, Nandita; Palmer, Jeanne; Chen, George L; Jagasia, Madan H; Mayer, Sebastian A; Wood, William A; Green, Michael; Hyun, Teresa S.; Inamoto, Yoshihiro; Storer, Barry E; Miklos, David B; Shulman, Howard M.; Martin, Paul J; Sarantopoulos, Stefanie; Lee, Stephanie J; Flowers, Mary E D

    2015-01-01

    Purpose Cutaneous sclerosis (CS) occurs in 20% of patients with chronic graft-versus-host disease (GVHD) and can compromise mobility and quality of life. Experimental design We conducted a prospective, multi-center, randomized, two-arm phase II crossover trial of imatinib (200 mg daily) or rituximab (375 mg/m2 intravenously weekly × 4 doses, repeatable after 3 months) for treatment of CS diagnosed within 18 months (NCT01309997). The primary endpoint was significant clinical response (SCR) at 6 months, defined as quantitative improvement in skin sclerosis or joint range of motion. Treatment success was defined as SCR at 6 months without crossover, recurrent malignancy or death. Secondary end points included changes of B cell profiles in blood (BAFF levels and cellular subsets), patient-reported outcomes, and histopathology between responders and non-responders with each therapy. Results SCR was observed in 9 of 35 (26%, 95% CI 13-43%) participants randomized to imatinib and 10 of 37 (27%, 95% CI 14-44%) randomized to rituximab. Six (17%, 95% CI 7-34%) patients in the imatinib arm and 5 (14%, 95% CI 5-29%) in the rituximab arm had treatment success. Higher percentages of activated B cells (CD27+) were seen at enrollment in rituximab-treated patients who had treatment success (p = 0.01), but not in imatinib-treated patients. Conclusion These results support the need for more effective therapies for CS and suggest that activated B cells define a subgroup of patients with CS who are more likely to respond to rituximab. PMID:26378033

  17. Long-Term Maintenance Therapy Using Rituximab-Induced Continuous B-Cell Depletion in Patients with ANCA Vasculitis

    PubMed Central

    Pendergraft, William F.; Cortazar, Frank B.; Wenger, Julia; Murphy, Andrew P.; Rhee, Eugene P.; Laliberte, Karen A.; Niles, John L.

    2014-01-01

    Background and objectives Remission in the majority of ANCA vasculitis patients is not sustained after a single course of rituximab, and risk of relapse warrants development of a successful strategy to ensure durable remission. Design, setting, participants, & measurements A retrospective analysis of ANCA vasculitis patients who underwent maintenance therapy using rituximab-induced continuous B-cell depletion for up to 7 years was performed. Maintenance therapy with rituximab was initiated after achieving remission or converting from other prior maintenance therapy. Continuous B-cell depletion was achieved in all patients by scheduled rituximab administration every 4 months. Disease activity, serologic parameters, adverse events, and survival were examined. Results In the study, 172 patients (mean age=60 years, 55% women, 57% myeloperoxidase–ANCA) treated from April of 2006 to March of 2013 underwent continuous B-cell depletion with rituximab. Median remission maintenance follow-up time was 2.1 years. Complete remission (Birmingham Vasculitis Activity Score [BVAS]=0) was achieved in all patients. Major relapse (BVAS≥3) occurred in 5% of patients and was associated with weaning of other immunosuppression drugs. Remission was reinduced in all patients. Survival mirrored survival of a general age-, sex-, and ethnicity-matched United States population. Conclusion This analysis provides evidence for long-term disease control using continuous B-cell depletion. This treatment strategy in ANCA vasculitis patients also seems to result in survival rates comparable with rates in a matched reference population. These findings suggest that prospective remission maintenance treatment trials using continuous B-cell depletion are warranted. PMID:24626432

  18. Trial Watch

    PubMed Central

    Vacchelli, Erika; Aranda, Fernando; Eggermont, Alexander; Galon, Jérôme; Sautès-Fridman, Catherine; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

    2014-01-01

    In 1997, for the first time in history, a monoclonal antibody (mAb), i.e., the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug Administration for use in cancer patients. Since then, the panel of mAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has not stopped to expand, nowadays encompassing a stunning amount of 15 distinct molecules. This therapeutic armamentarium includes mAbs that target tumor-associated antigens, as well as molecules that interfere with tumor-stroma interactions or exert direct immunostimulatory effects. These three classes of mAbs exert antineoplastic activity via distinct mechanisms, which may or may not involve immune effectors other than the mAbs themselves. In previous issues of OncoImmunology, we provided a brief scientific background to the use of mAbs, all types confounded, in cancer therapy, and discussed the results of recent clinical trials investigating the safety and efficacy of this approach. Here, we focus on mAbs that primarily target malignant cells or their interactions with stromal components, as opposed to mAbs that mediate antineoplastic effects by activating the immune system. In particular, we discuss relevant clinical findings that have been published during the last 13 months as well as clinical trials that have been launched in the same period to investigate the therapeutic profile of hitherto investigational tumor-targeting mAbs. PMID:24605265

  19. A chimeric measles virus with a lentiviral envelope replicates exclusively in CD4+/CCR5+ cells

    SciTech Connect

    Mourez, Thomas; Mesel-Lemoine, Mariana; Combredet, Chantal; Najburg, Valerie; Cayet, Nadege; Tangy, Frederic

    2011-10-25

    We generated a replicating chimeric measles virus in which the hemagglutinin and fusion surface glycoproteins were replaced with the gp160 envelope glycoprotein of simian immunodeficiency virus (SIVmac239). Based on a previously cloned live-attenuated Schwarz vaccine strain of measles virus (MV), this chimera was rescued at high titers using reverse genetics in CD4+ target cells. Cytopathic effect consisted in the presence of large cell aggregates evolving to form syncytia, as observed during SIV infection. The morphology of the chimeric virus was identical to that of the parent MV particles. The presence of SIV gp160 as the only envelope protein on chimeric particles surface altered the cell tropism of the new virus from CD46+ to CD4+ cells. Used as an HIV candidate vaccine, this MV/SIVenv chimeric virus would mimic transient HIV-like infection, benefiting both from HIV-like tropism and the capacity of MV to replicate in dendritic cells, macrophages and lymphocytes.

  20. Single-born marmosets without hemopoietic chimerism: naturally occurring and induced.

    PubMed

    Gengozian, N; Batson, J S

    1975-01-01

    Marmosets have a high frequency of fraternal twinning, and placental vascular anastomoses between the twin fetuses invariably lead to hemopoietic chimerism. The occasional finding of chimerism in single-born marmosets suggested that in a twin pregnancy one fetus had undergone resorption after contributing hemopoietic stem cells to its twin. In this study non-chimeric single-born marmosets were produced by fallopian tube ligation or surgical relocation of one ovary in breeding females. Further, in an examination of hemopoietic cells from over 50 single-born young from nonoperated females, chimerism occurred less frequently than what one would expect if resorption of a co-twin had occurred after a functional anastomosis had been established. PMID:808628

  1. A multicenter randomized open-label study of rituximab plus rhTPO vs rituximab in corticosteroid-resistant or relapsed ITP

    PubMed Central

    Zhou, Hai; Xu, Miao; Qin, Ping; Zhang, Hai-yan; Yuan, Cheng-lu; Zhao, Hong-guo; Cui, Zhong-guang; Meng, Yue-sheng; Wang, Lei; Zhou, Fang; Wang, Xin; Li, Da-qi; Bi, Ke-hong; Zhu, Chuan-sheng; Guo, Cheng-shan; Chu, Xiao-xia; Wu, Qing-chao; Liu, Xin-guang; Dong, Xiao-yuan; Li, Jie; Peng, Jun

    2015-01-01

    This study aimed to compare the efficacy and safety of rituximab (RTX) plus recombinant human thrombopoietin (rhTPO) with RTX alone in patients with immune thrombocytopenia (ITP) who had failed to respond to corticosteroids or relapsed. Recruited patients were randomized at a ratio of 2:1 into 2 groups: the combination group (RTX + rhTPO, n = 77) and the monotherapy group (RTX, n = 38). Overall response was achieved in 79.2% of patients in the combination group vs 71.1% in the monotherapy group (P = .36), and the complete response (CR) rate was 45.4% in the combination group compared with 23.7% in the monotherapy group (P = .026). The combination group had significantly shorter time to response (TTR; median and range, 7 and 4-28 days) compared with the monotherapy group (28 and 4-90 days) (P < .01). There was no difference between these 2 groups in terms of the long-term response (P = .12). Our findings demonstrated that the combination of RTX and rhTPO significantly increased the CR rate and shortened TTR compared with RTX monotherapy in the treatment of corticosteroid-resistant or relapsed ITP but failed to show a beneficial effect on the long-lasting response. This study is registered at www.clinicaltrials.gov as #NCT01525836. PMID:25575541

  2. Comparison of donor chimerism following myeloablative and nonmyeloablative allogeneic hematopoietic SCT.

    PubMed

    Mickelson, D M; Sproat, L; Dean, R; Sobecks, R; Rybicki, L; Kalaycio, M; Pohlman, B; Sweetenham, J; Andresen, S; Bolwell, B; Copelan, E A

    2011-01-01

    Surveillance of hematopoietic chimerism following hematopoietic SCT (HSCT) with nonmyeloablative (NMA) preparative regimens is standard to assess the need for clinical intervention. Monitoring of donor chimerism following HSCT with myeloablative (MA) preparative regimens is, however, not considered useful because engraftment is thought to occur rapidly and consistently. This study compares the timing of donor hematopoietic cell engraftment in patients undergoing NMA conditioning with fludarabine and TBI with those receiving MA conditioning with BU- or TBI-based regimens. Achievement of ≥ 90% donor leukocyte chimerism occurred rapidly and consistently in all three groups and time to achievement of ≥ 90% donor T cells was similar among the three groups (P = 0.57). Achievement of ≥ 90% donor leukocyte chimerism was not associated with risk of acute or chronic GVHD, graft rejection, relapse or all cause mortality in multivariate analyses. Donor T-cell chimerism of ≥ 90% was significantly associated with development of extensive chronic GVHD. The value of routine surveillance of chimerism following any of the preparative regimens used in this study should be reevaluated. PMID:20305699

  3. Targeting duplex DNA with chimeric α,β-triplex-forming oligonucleotides

    PubMed Central

    Kolganova, N. A.; Shchyolkina, A. K.; Chudinov, A. V.; Zasedatelev, A. S.; Florentiev, V. L.; Timofeev, E. N.

    2012-01-01

    Triplex-directed DNA recognition is strictly limited by polypurine sequences. In an attempt to address this problem with synthetic biology tools, we designed a panel of short chimeric α,β-triplex-forming oligonucleotides (TFOs) and studied their interaction with fluorescently labelled duplex hairpins using various techniques. The hybridization of hairpin with an array of chimeric probes suggests that recognition of double-stranded DNA follows complicated rules combining reversed Hoogsteen and non-canonical homologous hydrogen bonding. In the presence of magnesium ions, chimeric TFOs are able to form highly stable α,β-triplexes, as indicated by native gel-electrophoresis, on-array thermal denaturation and fluorescence-quenching experiments. CD spectra of chimeric triplexes exhibited features typically observed for anti-parallel purine triplexes with a GA or GT third strand. The high potential of chimeric α,β-TFOs in targeting double-stranded DNA was demonstrated in the EcoRI endonuclease protection assay. In this paper, we report, for the first time, the recognition of base pair inversions in a duplex by chimeric TFOs containing α-thymidine and α-deoxyguanosine. PMID:22641847

  4. Targeting duplex DNA with chimeric α,β-triplex-forming oligonucleotides.

    PubMed

    Kolganova, N A; Shchyolkina, A K; Chudinov, A V; Zasedatelev, A S; Florentiev, V L; Timofeev, E N

    2012-09-01

    Triplex-directed DNA recognition is strictly limited by polypurine sequences. In an attempt to address this problem with synthetic biology tools, we designed a panel of short chimeric α,β-triplex-forming oligonucleotides (TFOs) and studied their interaction with fluorescently labelled duplex hairpins using various techniques. The hybridization of hairpin with an array of chimeric probes suggests that recognition of double-stranded DNA follows complicated rules combining reversed Hoogsteen and non-canonical homologous hydrogen bonding. In the presence of magnesium ions, chimeric TFOs are able to form highly stable α,β-triplexes, as indicated by native gel-electrophoresis, on-array thermal denaturation and fluorescence-quenching experiments. CD spectra of chimeric triplexes exhibited features typically observed for anti-parallel purine triplexes with a GA or GT third strand. The high potential of chimeric α,β-TFOs in targeting double-stranded DNA was demonstrated in the EcoRI endonuclease protection assay. In this paper, we report, for the first time, the recognition of base pair inversions in a duplex by chimeric TFOs containing α-thymidine and α-deoxyguanosine. PMID:22641847

  5. Deletional and regulatory mechanisms coalesce to drive transplantation tolerance through mixed chimerism.

    PubMed

    Hock, Karin; Mahr, Benedikt; Schwarz, Christoph; Wekerle, Thomas

    2015-09-01

    Establishing donor-specific immunological tolerance could improve long-term outcome by obviating the need for immunosuppressive drug therapy, which is currently required to control alloreactivity after organ transplantation. Mixed chimerism is defined as the engraftment of donor hematopoietic stem cells in the recipient, leading to viable coexistence of both donor and recipient leukocytes. In numerous experimental models, cotransplantation of donor bone marrow (BM) into preconditioned (e.g., through irradiation or cytotoxic drugs) recipients leads to transplantation tolerance through (mixed) chimerism. Mixed chimerism offers immunological advantages for clinical translation; pilot trials have established proof of concept by deliberately inducing tolerance in humans. Widespread clinical application is prevented, however, by the harsh preconditioning currently necessary for permitting BM engraftment. Recently, the immunological mechanisms inducing and maintaining tolerance in experimental mixed chimerism have been defined, revealing a more prominent role for regulation than historically assumed. The evidence from murine models suggests that both deletional and regulatory mechanisms are critical in promoting complete tolerance, encompassing also the minor histocompatibility antigens. Here, we review the current understanding of tolerance through mixed chimerism and provide an outlook on how to realize widespread clinical translation based on mechanistic insights gained from chimerism protocols, including cell therapy with polyclonal regulatory T cells. PMID:26200095

  6. Chimeric Antigens of Toxoplasma gondii: Toward Standardization of Toxoplasmosis Serodiagnosis Using Recombinant Products

    PubMed Central

    Beghetto, Elisa; Spadoni, Andrea; Bruno, Luca; Buffolano, Wilma; Gargano, Nicola

    2006-01-01

    We have evaluated the diagnostic utility of six antigenic regions of the Toxoplasma gondii MIC2, MIC3, M2AP, GRA3, GRA7, and SAG1 gene products, assembled in recombinant chimeric antigens by genetic engineering, in order to replace the soluble, whole-cell tachyzoite extract in serological assays. Serum samples from 100 adults with acquired T. gondii infection and from 30 infants born to mothers with primary toxoplasmosis contracted during pregnancy, of whom 20 were congenitally infected, were included. Immunoglobulin G (IgG) and IgM antibodies against epitopes carried by chimeric antigens were measured by performing parallel enzyme immunoassays (recombinant enzyme-linked immunosorbent assays [Rec-ELISAs]), and the results obtained by standard commercial assays with the whole-cell Toxoplasma antigen and assays with the chimeric antigens were compared. Our results demonstrate that IgG and IgM Rec-ELISAs with individual chimeric antigens have performance characteristics comparable to those of the corresponding commercial assays. Furthermore, we show that IgM-capture assays based on chimeric antigens improve the ability to diagnose congenital toxoplasmosis postnatally compared with the ability to diagnose congenital toxoplasmosis by the use of standard assays. The use of recombinant chimeric antigens is effective in distinguishing T. gondii-infected individuals from T. gondii-uninfected individuals and shows that immunoassays based on recombinant products could provide the basis for standardized commercial tests for the serodiagnosis of toxoplasmosis. PMID:16757610

  7. Prognostic Utility of Routine Chimerism Testing at 2 – 6 Months after Allogeneic Hematopoietic Cell Transplantation

    PubMed Central

    Mossallam, Ghada I.; Kamel, Azza M.; Storer, Barry; Martin, Paul J.

    2009-01-01

    The utility of routine chimerism analysis as a prognostic indicator of subsequent outcomes after allogeneic hematopoietic cell transplantation (HCT) with myeloablative conditioning regimens remains controversial. To address this controversy, routine chimerism test results at 2 – 6 months after HCT with myeloablative conditioning regimens were evaluated for association with subsequent risks of chronic graft versus host disease (GVHD), non-relapse mortality (NRM), relapse and overall mortality. Only 70 (5%) of 1304 patients had <95% donor-derived cells in the marrow. Low donor chimerism in the marrow occurred predominantly among patients with low risk disease as compared to higher risk diseases and was significantly associated with a reduced risk of chronic GVHD. Among 673 patients tested, 164 (24%) had <85% donor-derived T cells in the blood. Low donor T cell chimerism occurred predominantly among patients with low risk disease as compared to higher risk diseases, among those who had conditioning with busulfan as compared to TBI, and among those with lower grades of acute GVHD. Low donor T cell chimerism in the blood was significantly associated with a reduced risk of chronic GVHD, but not with the risks of relapse, NRM or overall mortality. Routine testing of chimerism in the marrow and blood at 2 – 6 months after HCT with myeloablative conditioning regimens may be helpful in documenting engraftment in clinical trials but provides only limited prognostic information in clinical practice. PMID:19203726

  8. Antistaphylococcal activity of bacteriophage derived chimeric protein P128

    PubMed Central

    2012-01-01

    Background Bacterial drug resistance is one of the most significant challenges to human health today. In particular, effective antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA) are urgently needed. A causal relationship between nasal commensal S. aureus and infection has been reported. Accordingly, elimination of nasal S. aureus reduces the risk of infection. Enzymes that degrade bacterial cell walls show promise as antibacterial agents. Bacteriophage-encoded bacterial cell wall-degrading enzymes exhibit intrinsic bactericidal activity. P128 is a chimeric protein that combines the lethal activity of the phage tail-associated muralytic enzyme of Phage K and the staphylococcal cell wall targeting-domain (SH3b) of lysostaphin. Here we report results of in vitro studies evaluating the susceptibility of staphylococcal strains to this novel protein. Results Using the broth microdilution method adapted for lysostaphin, we found that P128 is effective against S. aureus clinical strains including MRSA, methicillin-sensitive S. aureus (MSSA), and a mupirocin-resistant S. aureus. Minimum bactericidal concentrations and minimum inhibitory concentrations of P128 (1-64 μg/mL) were similar across the 32 S. aureus strains tested, demonstrating its bactericidal nature. In time-kill assays, P128 reduced colony-forming units by 99.99% within 1 h and inhibited growth up to 24 h. In an assay simulating topical application of P128 to skin or other biological surfaces, P128 hydrogel was efficacious when layered on cells seeded on solid media. P128 hydrogel was lethal to Staphylococci recovered from nares of healthy people and treated without any processing or culturing steps, indicating its in situ efficacy. This methodology used for in vitro assessment of P128 as an agent for eradicating nasal carriage is unique. Conclusions The novel chimeric protein P128 is a staphylococcal cell wall-degrading enzyme under development for clearance of S. aureus nasal

  9. Corticosteroid-Free Primary Treatment of Chronic Extensive Graft-versus-Host Disease Incorporating Rituximab.

    PubMed

    Solomon, Scott R; Sizemore, Connie A; Ridgeway, Michelle; Zhang, Xu; Smith, Judith; Brown, Stacey; Holland, H Kent; Morris, Lawrence E; Bashey, Asad

    2015-09-01

    Chronic graft-versus-host disease (cGVHD) is a significant determinant of overall outcome and quality of life in survivors of allogeneic hematopoietic cell transplantation. Standard initial therapy of cGVHD is based on prolonged use of corticosteroids and a calcineurin inhibitor and has not changed for over 3 decades, despite limited efficacy and long-term toxicity. Rituximab is an attractive agent for the upfront treatment of cGVHD because of its favorable toxicity profile, efficacy in steroid-refractory cGVHD, and ability to serve as a steroid-sparing agent in autoimmune diseases. We hypothesized that a corticosteroid-free regimen incorporating rituximab would result in improved outcomes when used for the initial treatment of cGVHD. Twenty-five patients (median age, 56 years; range, 29 to 77) with extensive cGVHD were enrolled on a prospective phase II trial. Enrollment was limited to patients with first onset extensive cGVHD requiring systemic immunosuppression and without residual or concurrent acute graft-versus-host disease. cGVHD was classified as de novo, interrupted, and progressive in 12, 11, and 2 patients, respectively. cGVHD severity (National Institutes of Health grade) was mild, moderate, and severe in 3, 14, and 8 patients, respectively. All patients received rituximab 375 mg/m(2) × 4 weekly doses, then 1 dose every 3 months × 4 doses, in addition to mycophenolate mofetil and either tacrolimus or sirolimus. No other systemic immunosuppression was permitted, and only a short-course of steroids (≤4 weeks) was allowed at physician discretion; otherwise, treatment was deemed a failure and patients were treated off study. Twenty-two of 25 patients (88%) responded to treatment. Of the 22 responding patients, the median time to maximum response was 161 days (range, 35 to 300 days) with maximum response being complete in 21 of 22 patients and partial in 1 patient. Excluding the 3 patients taken off study for treatment failure, corticosteroids were used

  10. Drug-induced progressive multifocal leukoencephalopathy: Lessons learned from contrasting natalizumab and rituximab.

    PubMed

    Vermeer, N S; Straus, S M J M; Mantel-Teeuwisse, A K; Hidalgo-Simon, A; Egberts, A C G; Leufkens, H G M; De Bruin, M L

    2015-11-01

    Progressive multifocal leukoencephalopathy (PML) has been identified as a serious adverse drug reaction (ADR) of several immunomodulatory biologicals. In this study, we contrasted the reporting patterns of PML for two biologicals for which the risk was identified at different points in their lifecycle: natalizumab (before reapproval) and rituximab (nine years postapproval). We found that, apart from the differences in clinical characteristics (age, gender, indication, time to event, fatality), which reflect the diversity in context of use, PML reports for natalizumab were more complete and were received sooner after occurrence. This study serves as an important reminder that spontaneous reports should only be used with great caution to quantify and compare safety profiles across products over time. The observed variability in reporting patterns and heterogeneity of PML cases presents challenges to such comparisons. Lumping uncharacterized PML reports together without taking these differences into account may result in biased comparisons and flawed conclusions about differential safety. PMID:26347128

  11. Retroperitoneal fibrosis due to B-cell non-Hodgkin lymphoma: Responding to rituximab!

    PubMed

    Alvarez Argote, Juliana; Bauer, Frank A; Posteraro, Anthony F; Dasanu, Constantin A

    2016-02-01

    Retroperitoneal fibrosis is a rare disease manifesting as chronic soft tissue fibrosis in the retroperitoneum, with potential anatomic and/or functional compromise of adjacent organs. It can be primary (idiopathic) or secondary to other conditions such as cancers, autoimmune disorders, or drugs. We report herein a 66-year-old patient with symptomatic retroperitoneal fibrosis leading to bilateral hydronephrosis and renal failure, in whom, after a complex diagnostic work-up and protracted clinical course, a B-cell non-Hodgkin lymphoma in the retroperitoneal space and several vertebral bodies was identified. The patient was treated with radiation therapy and weekly rituximab infusions, with resolution of hydronephrosis and lower back pain. We include a thorough literature review on etiopathogenesis, diagnosis, therapy, and prognosis of retroperitoneal fibrosis. A meticulous search for malignancy is necessary in this rare condition that, if positive, may have significant therapeutic and prognostic implications. PMID:25013186

  12. Successful use of rituximab in refractory idiopathic thrombocytopenic purpura in a patient with common variable immunodeficiency.

    PubMed

    Al-Ahmad, M; Al-Rasheed, M; Al-Muhani, A

    2010-01-01

    Idiopathic thrombocytopenic purpura (ITP) is a common autoimmune disease in patients with common variable immunodeficiency (CVID). We describe a 36-year-old woman with CVID. The clinical course of her disease was complicated by bronchiectasis, antiphospholipid antibody syndrome, and portal vein thrombosis. She developed recurrent attacks of ITP refractory to high doses of corticosteroid, intravenous immunoglobulin (IVIG), and splenectomy. She received a total of 5 doses of rituximab (375 mg/m2) and achieved an immediate and persistent response. Therapy was well tolerated. Her platelet count remained above 370,000/microL for 8 months of follow-up, despite repeated infections. During this period the patient remained off corticosteroids and on continuous IVIG replacement therapy. PMID:20635793

  13. Clopidogrel-induced refractory thrombotic thrombocytopenic purpura successfully treated with rituximab.

    PubMed

    Khodor, Sara; Castro, Miguel; McNamara, Colin; Chaulagain, Chakra P

    2016-06-01

    Thrombotic thrombocytopenic purpura (TTP) is a multisystem disorder characterized by microvascular aggregation of platelets and fibrin strands causing thrombocytopenia, microangiopathic hemolytic anemia, and organ dysfunction. TTP can develop as a result of a deficiency in ADAMTS13 enzyme activity due to either a genetic defect or, more commonly, the development of anti-ADAMTS13 autoantibodies. TTP can also be associated with pregnancy, organ transplant, lupus, infections, and drugs. Here, we present a case of TTP that developed shortly after the start of clopidogrel treatment for acute ischemic stroke and acute myocardial infarction, and describe the clinical presentation, refractory course of the disease, and successful induction of remission through the use of rituximab in a setting of pre-existing autoimmune diseases. PMID:26684918

  14. Rituximab for the Treatment of Relapses in ANCA-associated Vasculitis

    PubMed Central

    Miloslavsky, EM; Specks, U; Merkel, PA; Seo, P; Spiera, R; Langford, CA; Hoffman, GS; Kallenberg, CGM; St. Clair, EW; Tchao, NK; Viviano, L; Ding, L; Ikle, D; Villarreal, M; Jepson, B; Brunetta, P; Allen, NB; Fervenza, FC; Geetha, D; Keogh, K; Kissin, EY; Monach, PA; Peikert, T; Stegeman, C; Ytterberg, SR; Stone, JH

    2014-01-01

    Introduction Disease relapses are frequent in antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV). We evaluated the outcomes of patients re-treated with rituximab (RTX) and prednisone for severe disease relapses. Methods The Rituximab in AAV trial was a randomized, double-blind, placebo-controlled trial comparing the rates of remission induction among patients treated with RTX (n = 99) and patients treated with cyclophosphamide (CYC) followed by azathioprine (AZA) (n = 98). Prednisone was tapered to discontinuation after 5.5 months. After achieving remission, patients who experienced a severe disease relapse between months 6 and 18 were eligible to receive RTX and prednisone on an open-label basis according to a pre-specified protocol. Investigators remained blinded to the original treatment assignment. Results Twenty-six patients received treatment with RTX for disease relapse after initially achieving remission on their originally assigned treatment. Fifteen patients were initially randomized to RTX and 11 to CYC/AZA. Thirteen (87%) of the patients originally assigned to RTX and 10 (91%) originally assigned to CYC/AZA achieved remission again with open-label RTX, an overall percentage of 88%. Half of the patients treated with open-label RTX were able to discontinue prednisone entirely. Patients in this cohort experienced fewer adverse events compared to the overall study population (4.7 adverse events/patient-year versus 11.8 adverse events/patient-year, respectively). Conclusion Re-treatment of AAV relapses with RTX and glucocorticoids appears to be a safe and effective strategy, regardless of previous treatment. PMID:25047592

  15. Rituximab Injection

    MedlinePlus

    ... with another medication to treat the symptoms of rheumatoid arthritis (RA; a condition in which the body attacks ... and CLL by killing cancer cells. It treats rheumatoid arthritis, granulomatosis with polyangiitis, and microscopic polyangiitis by blocking ...

  16. Rituximab Injection

    MedlinePlus

    ... a condition in which the body attacks its own joints, causing pain, swelling, and loss of function) ... are conditions in which the body attacks its own veins and other blood vessels, which causes damage ...

  17. The impact of MM5 and WRF meteorology over complex terrain on CHIMERE model calculations

    NASA Astrophysics Data System (ADS)

    de Meij, A.; Gzella, A.; Thunis, P.; Cuvelier, C.; Bessagnet, B.; Vinuesa, J. F.; Menut, L.

    2009-01-01

    The objective of this study is to evaluate the impact of meteorological input data on calculated gas and aerosol concentrations. We use two different meteorological models (MM5 and WRF) together with the chemistry transport model CHIMERE. We focus on the Po valley area (Italy) for January and June 2005. Firstly we evaluate the meteorological parameters with observations. The analysis shows that the performance of both models is similar, however some small differences are still noticeable. Secondly, we analyze the impact of using MM5 and WRF on calculated PM10 and O3 concentrations. In general CHIMERE/MM5 and CHIMERE/WRF underestimate the PM10 concentrations for January. The difference in PM10 concentrations for January between CHIMERE/MM5 and CHIMERE/WRF is around a factor 1.6 (PM10 higher for CHIMERE/MM5). This difference and the larger underestimation in PM10 concentrations by CHIMERE/WRF are related to the differences in heat fluxes and the resulting PBL heights calculated by WRF. In general the PBL height by WRF meteorology is a factor 2.8 higher at noon in January than calculated by MM5. This study showed that the difference in microphysics scheme has an impact on the profile of cloud liquid water (CLW) calculated by the meteorological driver and therefore on the production of SO4 aerosol. A sensitivity analysis shows that changing the Noah Land Surface Model (LSM) for the 5-layer soil temperature model, the calculated monthly mean PM10 concentrations increase by 30%, due to the change in the heat fluxes and the resulting PBL heights. For June, PM10 calculated concentrations by CHIMERE/MM5 and CHIMERE/WRF are similar and agree with the observations. Calculated O3 values for June are in general overestimated by a factor 1.3 by CHIMERE/MM5 and CHIMRE/WRF. The reason for this is that daytime NO2 concentrations are a higher than the observations and nighttime NO concentrations (titration effect) are underestimated.

  18. Generation of monoclonal antibodies of desired specificity using chimeric polyomavirus-derived virus-like particles.

    PubMed

    Zvirbliene, A; Samonskyte, L; Gedvilaite, A; Voronkova, T; Ulrich, R; Sasnauskas, K

    2006-04-20

    Foreign protein sequences presented on hamster polyomavirus (HaPyV) major capsid protein VP1-derived virus-like particles (VLPs) have been demonstrated to be highly immunogenic. The current study was aimed to evaluate VP1-derived chimeric VLPs as tools for hybridoma technology to generate monoclonal antibodies (mAbs) of desired specificity. Chimeric VLPs containing inserts of different size and origin were used as immunogens. Chimeric VLPs carrying a 9 amino acid (aa)-long cytotoxic T-cell epitope (STAPPVHNV) of human mucin 1 (MUC1) elicited a strong epitope-specific humoral immune response in mice and promoted the production of MUC1-specific mAbs. From a total of seven mAbs of IgG isotype generated against the chimeric VLPs, two mAbs were directed against the MUC1 epitope and five mAbs against the VP1-carrier. Two out of five anti-VP1 mAbs recognized epitopes located at the previously defined insertion site #2 (aa 223/224), which confirms its surface-exposed localization. Chimeric VLPs carrying a 120-aa long sequence of Puumala hantavirus (PUUV) nucleocapsid protein (NP) promoted the generation of five mAbs of IgG isotype specific to PUUV NP. All mAbs recognized the full-length NP of different PUUV strains. In contrast, no VP1-specific mAbs were obtained. The ability of chimeric VLPs to activate antigen-presenting cells was evaluated by studying the uptake of chimeric VLPs by murine spleen cell-derived dendritic cells (DCs). Efficient uptake of VLPs and activation of murine DCs were demonstrated, which may represent the basis of the strong immunogenicity of chimeric VLPs. In conclusion, chimeric VLPs effectively stimulated the production of IgG antibodies specific for foreign epitopes presented at surface-exposed regions. Thus, chimeric HaPyV VP1-derived VLPs represent efficient immunogens for hybridoma technology and provide a promising alternative to chemical coupling of synthetic peptides to carrier proteins. PMID:16516908

  19. Designing Chimeric Antigen Receptors to Effectively and Safely Target Tumors

    PubMed Central

    Jensen, Michael C.; Riddell, Stanley R.

    2015-01-01

    The adoptive transfer of T cells engineered to express artificial chimeric antigen receptors (CARs) that target a tumor cell surface molecule has emerged as an exciting new approach for cancer immunotherapy. Clinical trials in patients with advanced B cell malignancies treated with CD19-specific CAR-modified T cells (CAR-T) have shown impressive antitumor efficacy, leading to optimism that this approach will be useful for treating common solid tumors. Because CAR-T cells recognize tumor cells independent of their expression of human leukocyte antigen (HLA) molecules, tumors that escape conventional T cells by downregulating HLA and/or mutating components of the antigen processing machinery can be eliminated. The ability to introduce or delete additional genes in T cells has the potential to provide therapeutic cell products with novel attributes that overcome impediments to immune mediated tumor elimination in immunosuppressive tumor microenvironments. This review will discuss recent concepts in the development of effective and safe synthetic CARs for adoptive T cell therapy (ACT). PMID:25621840

  20. Chimeric antigen receptor-modified T cells strike back.

    PubMed

    Frigault, Matthew J; Maus, Marcela V

    2016-07-01

    Chimeric antigen receptors (CARs) are engineered molecules designed to endow a polyclonal T-cell population with the ability to recognize tumor-associated surface antigens. In their simplest form, CARs comprise a targeting moiety in the form of a single-chain variable fragment from an antibody connected to various intracellular signaling domains allowing for T-cell activation. This powerful approach combines the specificity of an antibody with the cytotoxic ability of a T cell. There has been much excitement since early phase trials of CAR-T cells targeting CD19 expressed on B-cell malignancies demonstrated remarkable efficacy in inducing long-term, stable remissions in otherwise relapsed/refractory disease. Despite these successes, we have just begun to understand the intricacies of CAR biology with efforts underway to utilize this platform in the treatment of other, previously refractory malignancies. Challenges currently include identification of viable cancer targets, management strategies for potentially severe and irreversible toxicities and overcoming the immunosuppressive nature of the tumor microenvironment. This review will focus on basic CAR structure and function, previous success and new approaches aimed at the broader application of CAR-T-cell therapy. PMID:27021308

  1. Development of chimeric antigen receptors for multiple myeloma.

    PubMed

    Martínez-Cingolani, Carolina; Bories, Jean Christophe

    2016-04-15

    Multiple myeloma (MM) is a haematologic malignancy characterized by the expansion of monoclonal plasma cells in the bone marrow. It is associated with serum or urine monoclonal protein and organ damage including renal failure, anaemia, hypercalcaemia and bone lesions. Despite recent improvements MM still remains an incurable disease. Previous studies have shown that the adoptive transfer of autologous T-cells modified to express chimeric antigen receptors (CAR) is effective in cases of acute and chronic lymphoid leukaemia. However, the adjustment of CAR-T-cell therapy to MM is hindered by the scarcity of antigens specific to the tumour plasma cells. Most candidate targets are shared by healthy tissues, and entail high risks of toxicity. Therefore several strategies have been proposed to regulate CAR-T-cell function as well as to enhance CAR-T-cell specificity against tumour cells. In this article we summarize the surface markers that have been investigated as targets to eliminate MM plasma cells and the MM-specific CARs that have been developed to date. Then we describe the different CAR-T-cell designs that could be applied in the case of MM to circumvent current problems of toxicity. PMID:27068946

  2. Toxicities of chimeric antigen receptor T cells: recognition and management.

    PubMed

    Brudno, Jennifer N; Kochenderfer, James N

    2016-06-30

    Chimeric antigen receptor (CAR) T cells can produce durable remissions in hematologic malignancies that are not responsive to standard therapies. Yet the use of CAR T cells is limited by potentially severe toxicities. Early case reports of unexpected organ damage and deaths following CAR T-cell therapy first highlighted the possible dangers of this new treatment. CAR T cells can potentially damage normal tissues by specifically targeting a tumor-associated antigen that is also expressed on those tissues. Cytokine release syndrome (CRS), a systemic inflammatory response caused by cytokines released by infused CAR T cells can lead to widespread reversible organ dysfunction. CRS is the most common type of toxicity caused by CAR T cells. Neurologic toxicity due to CAR T cells might in some cases have a different pathophysiology than CRS and requires different management. Aggressive supportive care is necessary for all patients experiencing CAR T-cell toxicities, with early intervention for hypotension and treatment of concurrent infections being essential. Interleukin-6 receptor blockade with tocilizumab remains the mainstay pharmacologic therapy for CRS, though indications for administration vary among centers. Corticosteroids should be reserved for neurologic toxicities and CRS not responsive to tocilizumab. Pharmacologic management is complicated by the risk of immunosuppressive therapy abrogating the antimalignancy activity of the CAR T cells. This review describes the toxicities caused by CAR T cells and reviews the published approaches used to manage toxicities. We present guidelines for treating patients experiencing CRS and other adverse events following CAR T-cell therapy. PMID:27207799

  3. Chimeric Antigen Receptor (CAR)-Engineered Lymphocytes for Cancer Therapy

    PubMed Central

    Ramos, Carlos A.; Dotti, Gianpietro

    2011-01-01

    Introduction Chimeric antigen receptors (CARs) usually combine the antigen binding site of a monoclonal antibody with the signal activating machinery of a T cell, freeing antigen recognition from major histocompatibility complex restriction and thus breaking one of the barriers to more widespread application of cellular therapy. Similar to treatment strategies employing monoclonal antibodies, T cells expressing CARs are highly targeted, but additionally offer the potential benefits of active trafficking to tumor sites, in vivo expansion and long term persistence. Furthermore, gene transfer allows the introduction of countermeasures to tumor immune evasion and of safety mechanisms. Areas covered The authors review the basic structure of so-called first and later generation CARs and their potential advantages over other immune therapy systems. It is described how these molecules can be grafted into immune cells (including retroviral and non-retroviral transduction methods) and strategies to improve the in vivo persistence and function of immune cells expressing CARs are discussed. Examples of tumor associated antigens that have been targeted in preclinical models are presented and clinical experience with these modified cells is summarized. Finally, a discussion on safety issues surrounding CAR gene transfer into T cells and potential solutions to them, are presented. Expert opinion Because of recent advances in immunology, genetics and cell processing, CAR-modified T cells will likely play an increasing role in the cellular therapy of cancer, chronic infections and autoimmune disorders. PMID:21463133

  4. Utilizing Chimeric Antigen Receptors to Direct Natural Killer Cell Activity

    PubMed Central

    Hermanson, David L.; Kaufman, Dan S.

    2015-01-01

    Natural killer (NK) cells represent an attractive lymphocyte population for cancer immunotherapy due to their ability to lyse tumor targets without prior sensitization and without need for human leukocyte antigens-matching. Chimeric antigen receptors (CARs) are able to enhance lymphocyte targeting and activation toward diverse malignancies. CARs consist of an external recognition domain (typically a small chain variable fragment) directed at a specific tumor antigen that is linked with one or more intracellular signaling domains that mediate lymphocyte activation. Most CAR studies have focused on their expression in T cells. However, use of CARs in NK cells is starting to gain traction because they provide a method to redirect these cells more specifically to target refractory cancers. CAR-mediated anti-tumor activity has been demonstrated using NK cell lines, as well as NK cells isolated from peripheral blood, and NK cells produced from human pluripotent stem cells. This review will outline the CAR constructs that have been reported in NK cells with a focus on comparing the use of different signaling domains in combination with other co-activating domains. PMID:25972867

  5. Current status of chimeric antigen receptor therapy for haematological malignancies.

    PubMed

    Maude, Shannon; Barrett, David M

    2016-01-01

    The field of adoptive cell transfer includes chimeric antigen receptor (CAR) engineered T cells, constructs that emerged from basic research into principles of immunology and have transformed into clinically effective therapies for haematological malignancies. T cells engineered to express these artificial receptors hold great promise, but also carry significant risk. While permanent genetic modification of mature T cells appears safe, modulating their in vivo function is difficult, partly because the robust response can trigger other arms of the immune system. Suicide systems and toxicity management with cytokine blockade or signal transduction modulators have emerged as a new frontier in this field, a far cry from early problems getting CAR T cells to work at all. Currently, clinical trials in patients with relapsed or refractory B cell malignancies treated with CD19-specific CAR T cells have induced durable remissions in adults and children. Results from these trials indicate that more work needs to be done to understand biomarkers of efficacy, the role of T cell persistence and how to integrate this care into standard practice. Cell therapy will not be a 'one size fits all' class of medicine, and here we will discuss the development of this therapy and important questions for its future. PMID:26560054

  6. Protective and immunological behavior of chimeric yellow fever dengue vaccine.

    PubMed

    Halstead, Scott B; Russell, Philip K

    2016-03-29

    Clinical observations from the third year of the Sanofi Pasteur chimeric yellow fever dengue tetravalent vaccine (CYD) trials document both protection and vaccination-enhanced dengue disease among vaccine recipients. Children who were 5 years-old or younger when vaccinated experienced a DENV disease resulting in hospitalization at 5 times the rate of controls. On closer inspection, hospitalized cases among vaccinated seropositives, those at highest risk to hospitalized disease accompanying a dengue virus (DENV) infection, were greatly reduced by vaccination. But, seronegative individuals of all ages after being vaccinated were only modestly protected from mild to moderate disease throughout the entire observation period despite developing neutralizing antibodies at high rates. Applying a simple epidemiological model to the data, vaccinated seronegative individuals of all ages were at increased risk of developing hospitalized disease during a subsequent wild type DENV infection. The etiology of disease in placebo and vaccinated children resulting in hospitalization during a DENV infection, while clinically similar are of different origin. The implications of the observed mixture of DENV protection and enhanced disease in CYD vaccinees are discussed. PMID:26873054

  7. Pancreas-protective effect of rituximab for acute-onset type 1 diabetes in the honeymoon period: a case report

    PubMed Central

    Kurozumi, Akira; Okada, Yosuke; Arao, Tadashi; Miyazaki, Yusuke; Yoshikawa, Maiko; Torimoto, Keiichi; Kubo, Satoshi; Nakayamada, Shingo

    2016-01-01

    Summary A randomized controlled study of rituximab demonstrated that the drug protects pancreatic function in patients with acute-onset type 1 diabetes mellitus (AOT1DM). However, the mechanism of this protective effect is poorly understood. We examined the effects of rituximab in two patients with AOT1DM in the honeymoon period and the mechanism of these effects. Case 1 was a 40-year-old man and Case 2 was a 45-year-old man, both diagnosed with AOT1DM. Various tests indicated intact capacity for endogenous insulin secretion and that they were in the honeymoon phase of AOT1DM. Treatment with rituximab protected against pancreatic β-cell damage and maintained somewhat the endogenous insulin secretion. In Case 2, HbA1c level was maintained below 6.5% up to 24 months after treatment. However, in Case 1, the patient showed a gradual increase in HbA1c level starting around 9 months but fell at 12 months to >9.0% and required an insulin dose about twice greater than that of Case 2. High spleen tyrosine kinase (Syk) levels were recorded in the two patients before rituximab administration and after the treatment, the levels were further increased in Case 1, but decreased in Case 2. Both patients require continuous careful follow-up for glycemic control, insulin secretion capacity, and adverse reactions in the future. Although the clinical relevance of high Syk levels in AOT1DM patients remains unclear, the difference in the change in Syk level between the two patients may explain the different clinical courses. Learning points We described the pancreas-protective effect of rituximab in two patients with acute-onset type 1 diabetes mellitus in the honeymoon period and investigated the possible mechanism of action. The present study demonstrated that treatment with rituximab maintained endogenous insulin secretion capacity for 2 years in the two patients. The phosphorylated-spleen tyrosine kinase (p-Syk) data suggest that the differences in HbA1c level and the required

  8. Successful Treatment of Life-Threatening Interstitial Lung Disease Secondary to Antisynthetase Syndrome Using Rituximab: A Case Report and Review of the Literature.

    PubMed

    Dasa, Osama; Ruzieh, Mohammed; Oraibi, Omar

    2016-01-01

    We are presenting a case of antisynthetase syndrome (ASS) that manifested with severe interstitial pneumonitis in the presence of anti-Jo-1 and Ro (SSA) antibodies. Our patient developed respiratory failure with high oxygen requirements despite treatment by high-dose steroids. The patient was then treated with rituximab. This treatment led to significant improvement in the patient condition, with resolution of the ground glass opacities on high-resolution computerized tomography and near normalization of pulmonary function tests. In this communication, we performed a literature review and summarized previous reports pertinent to using of rituximab to treat interstitial lung disease (ILD) secondary to ASS by searching the PubMed database from 1980 to 2014. We were able to find 14 reports that included total of 45 patients with ILD secondary to ASS. A significant improvement in ILD was reported in the majority of reported patients who received rituximab, while there was only 1 mortality-related to Pneumocystis jirovecii pneumonia. Rituximab treatment was tolerated well in the majority of cases. It is our conclusion that rituximab can be considered a therapeutic option in ILD secondary to ASS based on our experience with this case and the currently available evidence in the literature. Nevertheless, there is a need for additional controlled studies to assess the efficacy and safety of rituximab in ILD secondary to ASS compared with other immunosuppressive regimens. PMID:25830868

  9. Impact of hematopoietic chimerism at day +14 on engraftment after unrelated donor umbilical cord blood transplantation for hematologic malignancies

    PubMed Central

    Moscardó, Federico; Sanz, Jaime; Senent, Leonor; Cantero, Susana; de la Rubia, Javier; Montesinos, Pau; Planelles, Dolores; Lorenzo, Ignacio; Cervera, Jose; Palau, Javier; Sanz, Miguel A.; Sanz, Guillermo F.

    2009-01-01

    Background Cord blood transplant is a feasible treatment alternative for adult patients with hematologic malignancies lacking a suitable HLA-matched donor. However, the kinetics of myeloid recovery is slow, and primary graft failure cannot be detected easily early after transplantation. We investigated the impact of hematopoietic chimerism status from unselected marrow cells 14 days after transplantation on predicting engraftment after a cord blood transplant. Design and Methods Seventy-one adult patients with hematologic malignancies undergoing single-unit unrelated donor cord blood transplantation after a myeloablative conditioning regimen were included in the study. All patients received conditioning regimens based on busulfan, thiotepa and antithymocyte globulin. Chimerism status was assessed analyzing short tandem repeat polymorphisms. Results The cumulative incidence of myeloid engraftment at 1 month was significantly lower in patients with mixed chimerism than in those with complete donor chimerism (55% vs. 94%; p<0.0001). For patients achieving myeloid recovery, the median time of engraftment was 16 days when donor chimerism at day + 14 was higher than 90%, compared with 24 days when donor chimerism was below this level (p<0.001). A donor chimerism level of 65% was found to be the best cut-off point for predicting primary graft failure, with a sensitivity of 97% and a specificity of 80%. The incidence of primary graft failure was 67% for patients with less than 65% donor chimerism at day +14 as compared to only 2% for those with more than 65% donor chimerism (p<0.001). Patients with mixed chimerism also had a lower cumulative incidence of platelet engraftment than those with complete chimerism (62% vs. 89%; p=0.01). Conclusions Donor-recipient chimerism status at day +14 predicts engraftment after a single-unit cord blood transplant in adults. PMID:19483157

  10. Obinutuzumab for relapsed or refractory indolent non-Hodgkin’s lymphomas

    PubMed Central

    Gabellier, Ludovic; Cartron, Guillaume

    2016-01-01

    The use of anti-CD20 monoclonal antibodies (mAbs), such as rituximab, in CD20-positive B-cell malignancies has dramatically improved the outcome of chronic lymphoid leukemia and non-Hodgkin’s lymphomas (NHL). However, the occurrence of relapse and development of rituximab-refractory disease highlight the need to develop novel anti-CD20 mAbs, with improved mechanisms of action. Obinutuzumab is the first humanized type II glycoengineered anti-CD20 mAb. In vitro and in vivo data suggested several differences compared with rituximab, including a low level of complement-dependent cytotoxicity and an increased direct nonapoptotic cell death. Moreover, the glycoengineered Fc-linked nonfucosylated oligosaccharide enhanced the Fc–Fcγ receptor (FcγR) IIIa interaction, resulting in improved antibody-dependent cellular cytotoxicity and phagocytosis. Preclinical models suggested that these differences translate into superior survival in murine lymphoma models. Phase I/II trials in monotherapy in relapsed or refractory B-cell NHL demonstrated that obinutuzumab has an acceptable safety profile, infusion-related reactions being the most common adverse event. In rituximab-refractory indolent NHL, the recent randomized phase III GADOLIN study demonstrated an improved median progression-free survival for patients treated with obinutuzumab plus bendamustine rather than bendamustine alone. Further trials are ongoing to determine the role of obinutuzumab as a first-line agent in the treatment of follicular lymphoma. PMID:27054024

  11. Patterns and kinetics of T-cell chimerism after allo transplant with alemtuzumab-based conditioning: mixed chimerism protects from GVHD, but does not portend disease recurrence.

    PubMed

    van Besien, Koen; Dew, Alexander; Lin, Shang; Joseph, Loren; Godley, Lucy A; Larson, Richard A; Odenike, Toyosi; Rich, Elizabeth; Stock, Wendy; Wickrema, Amittha; Artz, Andrew S

    2009-11-01

    We analyzed the kinetics of CD3 chimerism in 120 consecutive allogeneic hematopoietic cell transplantation (HCT) recipients receiving alemtuzumab-based conditioning. Fifty-two received fludarabine/melphalan, 44 received fludarabine/busulfan, and 24 received clofarabine/melphalan in addition to alemtuzumab. Post-transplant GVHD prophylaxis consisted of tacrolimus. No prophylactic donor lymphocyte infusion or other interventions were used for mixed donor chimerism (MDC). Bone marrow (BM) and/or peripheral blood (PB) samples were obtained at 30 days, 100 days, 180 days, and 1 year following HCT. On Day 30, 15% of assessable patients had MDC in the CD3 compartment. This had increased to 50% by Day 100, and to 63% by Day 180. MDC predicted for a lower risk of acute (p = 0.08) and particularly of chronic GVHD (p = 0.01). MDC was not associated with subsequent relapse or TRM (p = 0.67 and 0.72, respectively). A decline of more than 15% in CD3 chimerism between Day 30 and Day 180 predicted for a 40% risk of subsequent disease recurrence. The observation of MDC after alemtuzumab conditioning does not by itself constitute a risk factor for relapse and should not be used to guide therapeutic intervention. By contrast, declining donor chimerism between Day 30 and Day 180 is associated with a somewhat increased risk of disease recurrence. The high incidence of MDC after alemtuzumab containing conditioning contributes to the low risk of acute and chronic GVHD. PMID:19821799

  12. Evidence for Kidney Rejection after Combined Bone Marrow and Renal Transplantation Despite Ongoing Whole-blood Chimerism in Rhesus Macaques

    PubMed Central

    Ramakrishnan, Swetha K; Page, Andrew; Farris, Alton B.; Singh, Karnail; Leopardi, Frank; Hamby, Kelly; Sen, Sharon; Polnett, Aneesah; Deane, Taylor; Song, Mingqing; Stempora, Linda; Strobert, Elizabeth; Kirk, Allan D.; Larsen, Christian P.; Kean, Leslie S.

    2012-01-01

    Although there is evidence linking hematopoietic chimerism-induction and solid organ transplant tolerance, the mechanistic requirements for chimerism-induced tolerance are not clearly elucidated. To address this, we used an MHC-defined primate model to determine the impact of impermanent, T cell-poor, mixed-chimerism on renal allograft survival. We compared two cohorts: one receiving a bone marrow + renal transplant (“BMT/renal”) and one receiving only a renal transplant. Both cohorts received maintenance immunosuppression with CD28/CD40-directed costimulation blockade and sirolimus. As previously demonstrated, this transplant strategy consistently induced compartmentalized donor chimerism, (significant whole-blood chimerism, lacking T cell chimerism). This chimerism was not sufficient to prolong renal allograft acceptance: the BMT/renal mean survival time (MST, 76 days) was not significantly different than the renal transplant alone MST (85 days, p= 0. 46), with histopathology documenting T-cell mediated rejection. Flow cytometric analysis revealed significant enrichment for CD28-/CD95+ CD4+ and CD8+ Tem cells in the rejected kidney, suggesting a link between CD28-negative Tem and costimulation blockade-resistant rejection. These results suggest that in some settings, transient T cell-poor chimerism is not sufficient to induce tolerance to a concurrently placed renal allograft and that the presence of this chimerism per se is not an independent biomarker to identify tolerance. PMID:22642491

  13. Application of chimeric glucanase comprising mutanase and dextranase for prevention of dental biofilm formation.

    PubMed

    Otsuka, Ryoko; Imai, Susumu; Murata, Takatoshi; Nomura, Yoshiaki; Okamoto, Masaaki; Tsumori, Hideaki; Kakuta, Erika; Hanada, Nobuhiro; Momoi, Yasuko

    2015-01-01

    Water-insoluble glucan (WIG) produced by mutans streptococci, an important cariogenic pathogen, plays an important role in the formation of dental biofilm and adhesion of biofilm to tooth surfaces. Glucanohydrolases, such as mutanase (α-1,3-glucanase) and dextranase (α-1,6-glucanase), are able to hydrolyze WIG. The purposes of this study were to construct bi-functional chimeric glucanase, composed of mutanase and dextranase, and to examine the effects of this chimeric glucanase on the formation and decomposition of biofilm. The mutanase gene from Paenibacillus humicus NA1123 and the dextranase gene from Streptococcus mutans ATCC 25175 were cloned and ligated into a pE-SUMOstar Amp plasmid vector. The resultant his-tagged fusion chimeric glucanase was expressed in Escherichia coli BL21 (DE3) and partially purified. The effects of chimeric glucanase on the formation and decomposition of biofilm formed on a glass surface by Streptococcus sobrinus 6715 glucosyltransferases were then examined. This biofilm was fractionated into firmly adherent, loosely adherent, and non-adherent WIG fractions. Amounts of WIG in each fraction were determined by a phenol-sulfuric acid method, and reducing sugars were quantified by the Somogyi-Nelson method. Chimeric glucanase reduced the formation of the total amount of WIG in a dose-dependent manner, and significant reductions of WIG in the adherent fraction were observed. Moreover, the chimeric glucanase was able to decompose biofilm, being 4.1 times more effective at glucan inhibition of biofilm formation than a mixture of dextranase and mutanase. These results suggest that the chimeric glucanase is useful for prevention of dental biofilm formation. PMID:25411090

  14. Cryo-electron Microscopy Structures of Chimeric Hemagglutinin Displayed on a Universal Influenza Vaccine Candidate

    PubMed Central

    Tran, Erin E. H.; Podolsky, Kira A.; Bartesaghi, Alberto; Kuybeda, Oleg; Grandinetti, Giovanna; Wohlbold, Teddy John; Tan, Gene S.; Nachbagauer, Raffael; Palese, Peter; Krammer, Florian

    2016-01-01

    ABSTRACT Influenza viruses expressing chimeric hemagglutinins (HAs) are important tools in the quest for a universal vaccine. Using cryo-electron tomography, we have determined the structures of a chimeric HA variant that comprises an H1 stalk and an H5 globular head domain (cH5/1 HA) in native and antibody-bound states. We show that cH5/1 HA is structurally different from native HA, displaying a 60° rotation between the stalk and head groups, leading to a novel and unexpected “open” arrangement of HA trimers. cH5/1N1 viruses also display higher glycoprotein density than pH1N1 or H5N1 viruses, but despite these differences, antibodies that target either the stalk or head domains of hemagglutinins still bind to cH5/1 HA with the same consequences as those observed with native H1 or H5 HA. Our results show that a large range of structural plasticity can be tolerated in the chimeric spike scaffold without disrupting structural and geometric aspects of antibody binding. Importance Chimeric hemagglutinin proteins are set to undergo human clinical trials as a universal influenza vaccine candidate, yet no structural information for these proteins is available. Using cryo-electron tomography, we report the first three-dimensional (3D) visualization of chimeric hemagglutinin proteins displayed on the surface of the influenza virus. We show that, unexpectedly, the chimeric hemagglutinin structure differs from those of naturally occurring hemagglutinins by displaying a more open head domain and a dramatically twisted head/stalk arrangement. Despite this unusual spatial relationship between head and stalk regions, virus preparations expressing the chimeric hemagglutinin are fully infectious and display a high glycoprotein density, which likely helps induction of a broadly protective immune response. PMID:27006464

  15. Antigenic properties of a transport-competent influenza HA/HIV Env chimeric protein

    SciTech Connect

    Ye Ling; Sun Yuliang; Lin Jianguo; Bu Zhigao; Wu Qingyang; Jiang, Shibo; Steinhauer, David A.; Compans, Richard W.; Yang Chinglai . E-mail: chyang@emory.edu

    2006-08-15

    The transmembrane subunit (gp41) of the HIV Env glycoprotein contains conserved neutralizing epitopes which are not well-exposed in wild-type HIV Env proteins. To enhance the exposure of these epitopes, a chimeric protein, HA/gp41, in which the gp41 of HIV-1 89.6 envelope protein was fused to the C-terminus of the HA1 subunit of the influenza HA protein, was constructed. Characterization of protein expression showed that the HA/gp41 chimeric proteins were expressed on cell surfaces and formed trimeric oligomers, as found in the HIV Env as well as influenza HA proteins. In addition, the HA/gp41 chimeric protein expressed on the cell surface can also be cleaved into 2 subunits by trypsin treatment, similar to the influenza HA. Moreover, the HA/gp41 chimeric protein was found to maintain a pre-fusion conformation. Interestingly, the HA/gp41 chimeric proteins on cell surfaces exhibited increased reactivity to monoclonal antibodies against the HIV Env gp41 subunit compared with the HIV-1 envelope protein, including the two broadly neutralizing monoclonal antibodies 2F5 and 4E10. Immunization of mice with a DNA vaccine expressing the HA/gp41 chimeric protein induced antibodies against the HIV gp41 protein and these antibodies exhibit neutralizing activity against infection by an HIV SF162 pseudovirus. These results demonstrate that the construction of such chimeric proteins can provide enhanced exposure of conserved epitopes in the HIV Env gp41 and may represent a novel vaccine design strategy for inducing broadly neutralizing antibodies against HIV.

  16. Comprehensive Exploration of Novel Chimeric Transcripts in Clear Cell Renal Cell Carcinomas Using Whole Transcriptome Analysis

    PubMed Central

    Gotoh, Masahiro; Ichikawa, Hitoshi; Arai, Eri; Chiku, Suenori; Sakamoto, Hiromi; Fujimoto, Hiroyuki; Hiramoto, Masaki; Nammo, Takao; Yasuda, Kazuki; Yoshida, Teruhiko; Kanai, Yae

    2014-01-01

    The aim of this study was to clarify the participation of expression of chimeric transcripts in renal carcinogenesis. Whole transcriptome analysis (RNA sequencing) and exploration of candidate chimeric transcripts using the deFuse program were performed on 68 specimens of cancerous tissue (T) and 11 specimens of non-cancerous renal cortex tissue (N) obtained from 68 patients with clear cell renal cell carcinomas (RCCs) in an initial cohort. As positive controls, two RCCs associated with Xp11.2 translocation were analyzed. After verification by reverse transcription (RT)-PCR and Sanger sequencing, 26 novel chimeric transcripts were identified in 17 (25%) of the 68 clear cell RCCs. Genomic breakpoints were determined in five of the chimeric transcripts. Quantitative RT-PCR analysis revealed that the mRNA expression levels for the MMACHC, PTER, EPC2, ATXN7, FHIT, KIFAP3, CPEB1, MINPP1, TEX264, FAM107A, UPF3A, CDC16, MCCC1, CPSF3, and ASAP2 genes, being partner genes involved in the chimeric transcripts in the initial cohort, were significantly reduced in 26 T samples relative to the corresponding 26 N samples in the second cohort. Moreover, the mRNA expression levels for the above partner genes in T samples were significantly correlated with tumor aggressiveness and poorer patient outcome, indicating that reduced expression of these genes may participate in malignant progression of RCCs. As is the case when their levels of expression are reduced, these partner genes also may not fully function when involved in chimeric transcripts. These data suggest that generation of chimeric transcripts may participate in renal carcinogenesis by inducing dysfunction of tumor-related genes. PMID:25230976

  17. Rituximab does not improve clinical outcome in a randomized phase 3 trial of CHOP with or without rituximab in patients with HIV-associated non-Hodgkin lymphoma: AIDS-Malignancies Consortium Trial 010

    PubMed Central

    Kaplan, Lawrence D.; Lee, Jeannette Y.; Ambinder, Richard F.; Sparano, Joseph A.; Cesarman, Ethel; Chadburn, Amy; Levine, Alexandra M.; Scadden, David T.

    2005-01-01

    The addition of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy results in significant improvement in clinical outcome for individuals with non–HIV-associated aggressive B-cell lymphoma. To assess the potential risks and benefits of the addition of rituximab to CHOP for HIV-associated non-Hodgkin lymphoma (HIV-NHL) 150 patients receiving CHOP for HIV-NHL were randomized (2:1) to receive 375 mg/m2 rituximab with each chemotherapy cycle (n = 99) or no immunotherapy (n = 50) in a multicenter phase 3 trial. The complete response rate (CR + CRu) was 57.6% for R-CHOP and 47% for CHOP (P = .147). With a median follow-up of 137 weeks, time to progression, progression-free survival, and overall survival times were 125, 45, and 139 weeks, respectively, for R-CHOP and 85, 38, and 110 weeks, respectively, for CHOP (P = not significant, all comparisons). Treatment-related infectious deaths occurred in 14% of patients receiving R-CHOP compared with 2% in the chemotherapy-alone group (P = .035). Of these deaths, 60% occurred in patients with CD4 counts less than 50/mm3. Progression-free survival was significantly influenced by CD4+ count (P < .001) and International Prognostic Index score (P = .022), but not bcl-2 status. The addition of rituximab to CHOP in patients with HIV-NHL may be associated with improved tumor responses. However, these benefits may be offset by an increase in infectious deaths, particularly in those individuals with CD4+ lymphocyte counts less than 50/mm3. PMID:15914552

  18. Yttrium-90-ibritumomab tiuxetan radioimmunotherapy: a new treatment approach for B-cell non-Hodgkin's lymphoma.

    PubMed

    Witzig, Thomas E

    2004-02-01

    This article will review the clinical development of ibritumomab tiuxetan, a yttrium-90-conjugated monoclonal antibody to CD20, for patients with relapsed B-cell non-Hodgkin's lymphomas. Ibritumomab is the murine parent anti-CD20 antibody that was engineered to make the human chimeric antibody rituximab. Tiuxetan is an MX-DTPA chelator that is linked to ibritumomab to form ibritumomab tiuxetan. Since yttrium-90 ((90)Y) is a pure beta emitter and cannot be used for patient imaging, indium-111 ((111)In) is chelated to ibritumomab tiuxetan for tumor and normal organ imaging in clinical practice and for dosimetry in clinical trials. (90)Y-ibritumomab tiuxetan is the form used for therapy. This review discusses the clinical trials that have demonstrated the efficacy of ibritumomab tiuxetan and summarizes the safety data in patients with relapsed B-cell non-Hodgkin's lymphomas. Two phase I trials of (90)Y-ibritumomab tiuxetan were conducted to establish the toxicity profile and the maximum tolerated single dose that could be administered to outpatients without the use of stem cells or prophylactic growth factors. In the first trial, cold ibritumomab was used prior to ibritumomab tiuxetan; the second trial used the human chimeric antibody rituximab. The phase I trials determined that in patients with a platelet count of greater than or equal to 150 x 10(9)/l, a schedule of intravenous rituximab 250 mg/m(2) on days 1 and 8, and 0.4 mCi/ kg of intravenous (90)Y-ibritumomab tiuxetan on day 8 was safe and efficacious and did not require stem cells. A dose of 0.3 mCi/kg was recommended for patients with a baseline platelet count of 100,000- 149,000 x 10(6)/l. Adverse events were primarily hematologic, and nonhematologic adverse events were primarily due to rituximab. There was no normal organ toxicity. The overall response rate was 67% for all patients and 82% in patients with low-grade non-Hodgkin's lymphomas. A subsequent phase III trial randomized 143 eligible patients to

  19. Granulomatosis with polyangiitis (Wegener's granulomatosis) with hard palate and bronchial perforations treated with rituximab - a case report.

    PubMed

    Kosałka, Joanna; Bazan-Socha, Stanisława; Zugaj, Anna; Ignacak, Maria; Zuk, Joanna; Sokołowska, Barbara; Musiał, Jacek

    2014-01-01

    We present a case of a 57-year-old woman suffering from granulomatosis with polyangiitis (GPA), who in the seventh months of immunosuppressive treatment (cyclophosphamide) progressed with new pulmonary changes and perforations of the hard palate and bronchi. Rituximab was introduced resulting in B-cell depletion and disappearance of anti-PR3 antibody. Palatal holes have substantially diminished and all bronchial perforations disappeared, covered by fibrous tissue. In the fourth month after rituximab administration, large scarring obstruction of the right main bronchus with upper and middle lobes atelectasis emerged. Because of increasing dyspnoea, stenotic bronchus was re-opened by bronchoscopy. Intervention was complicated by bilateral pneumothorax and later, on the seventh day, by fatal pulmonary bleeding. To our knowledge, this is the first report of GPA refractory to cyclophosphamide complicated by palatal and bronchial perforations. PMID:25133814

  20. An update on the evidence for the efficacy and safety of rituximab in the management of neuromyelitis optica

    PubMed Central

    Collongues, Nicolas; de Seze, Jérôme

    2016-01-01

    Neuromyelitis optica spectrum disorders (NMOSDs) is a new concept which includes classical neuromyelitis optica (NMO) and partial forms of NMO such as recurrent optic neuritis with positive aquaporin-4 antibodies (AQP4) or brainstem symptoms (intractable hiccups or vomiting). This disease is clearly distinguished from multiple sclerosis (MS) and the therapeutic approach is clearly different. Rituximab is actually considered to be one of the most efficient treatments of NMOSD, even if class I studies are clearly lacking. In the present review, we describe the state of the art about rituximab treatment in NMOSD, including adults and children, plus its efficacy and tolerance and we also underline the questions that should be addressed in the near future. PMID:27134673

  1. An update on the evidence for the efficacy and safety of rituximab in the management of neuromyelitis optica.

    PubMed

    Collongues, Nicolas; de Seze, Jérôme

    2016-05-01

    Neuromyelitis optica spectrum disorders (NMOSDs) is a new concept which includes classical neuromyelitis optica (NMO) and partial forms of NMO such as recurrent optic neuritis with positive aquaporin-4 antibodies (AQP4) or brainstem symptoms (intractable hiccups or vomiting). This disease is clearly distinguished from multiple sclerosis (MS) and the therapeutic approach is clearly different. Rituximab is actually considered to be one of the most efficient treatments of NMOSD, even if class I studies are clearly lacking. In the present review, we describe the state of the art about rituximab treatment in NMOSD, including adults and children, plus its efficacy and tolerance and we also underline the questions that should be addressed in the near future. PMID:27134673

  2. Progressive multifocal leukoencephalopathy (PML) in a patient with lymphoma treated with rituximab: A case report and literature review.

    PubMed

    Al-Tawfiq, Jaffar A; Banda, Ramzi W; Daabil, Riyadh A; Dawamneh, M F

    2015-01-01

    Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease caused by reactivation of a latent JC polyoma virus. The first cases of PML were described 50 years ago in patients with lymphoma. PML typically occurs in immunocompromised individuals, particularly those infected with HIV. We present a 52-year-old male with lymphoma who was treated with R-CHOP (R: Rituximab; C: Cyclophosphamide; H: Doxorubicin; O: Vincristine; P: Prednisone). After six cycles of therapy, the patients developed tonic-clonic seizure. MRI of the brain showed multiple brain lesions. The pathology of a brain biopsy was diagnostic for PML. We review radiographic and histopathological features of the disease. The literature on PML and its association with immunosuppressant agents is reviewed, and the impact of rituximab and other biological agents in the setting is highlighted. PMID:25666327

  3. Improvement of paraneoplastic limbic encephalitis after systemic treatment with rituximab in a patient with B-cell chronic lymphocytic leukemia.

    PubMed

    Nogai, Hendrik; Israel-Willner, Heike; Zschenderlein, Rolf; Pezzutto, Antonio

    2013-01-01

    Limbic encephalitis is an inflammatory disease of the central nervous system characterized by diverse neurologic symptoms including mnestic disturbances, hallucinations, and seizures as well as behavioral symptoms like depression, personality changes, and acute confusional states resembling dementia. Several antibodies have been described in the pathogenesis of limbic encephalitis. It is often a paraneoplastic syndrome associated with small cell lung cancer, breast cancer, or Hodgkin's lymphoma among others. Here, we report a patient with B-cell chronic lymphocytic leukemia (B-CLL), presenting with otherwise unexplained neurologic symptoms consistent with limbic encephalitis. Despite intensive diagnostic procedures, no causing agent could be identified. Pleocytosis consisting of T cells was detected in the cerebrospinal fluid (CSF). We initiated anti-B-cell therapy with Rituximab for B-CLL with quick and durable resolution of symptoms. We speculate that disruption of interaction between autoreactive T and malignant B cells is responsible for the therapeutic effect of Rituximab. PMID:23984126

  4. An optimization of protocol for mixed chimerism induction in mice model.

    PubMed

    Baśkiewicz-Masiuk, M; Grymuła, K; Pius, E; Hałasa, M; Dziedziejko, V; Schmidt, Ch; Walczak, M; Machaliński, B

    2009-01-01

    Studies on mixed chimerism are currently focused primarily on obtaining less toxic conditioning protocols. With these issues in mind, we have undertaken the attempt to optimize the procedure of mixed chimerism induction in mice. In order to reduce toxicity, we used decreasing doses of total body irradiation (TBI) together with combination of blocking antibodies. We also tried to eliminate immunosuppression (cyclophosphamide - CP) treatment after bone marrow transplantation. B6.SJL-PtprcaPep3b mice were injected with 20-30 x 106 bone marrow cells from Balb C mice. Mice were treated with TBI (3 - 1.5 - 0 Gy) on "-1" day of the experiment and blocking antibodies against CD40L ("0", and "4" days) and additionally anti-CD8 ("-2" day) and/or anti-NK1.1 ("-3" day). Mice in certain groups also received CP (175 mg/kg) on "2" day. Presence of mixed chimerism was assessed in peripheral blood cells by flow cytometry on the 1st, 2nd, 3rd, 4th, 6th and 8th weeks of the experiment by detecting of CD45.1 (characteristic for B6.SJL-PtprcaPep3b strain) and CD45.2 (characteristic for Balb C strain) antigens expression. We also analyzed the percentage of peripheral blood CD8 T-cells (CD3e/CD8a) and NK cells (Ly-49D/NK1.1). We found that reduction of TBI dose and elimination of CP decrease the rate of mixed chimerism formation. The highest percentage of donor cells was obtained in the group of animals treated with 3 Gy of TBI, CP and combination of anti-CD40L, anti-CD8, and anti-NK1.1 antibodies. The 3 Gy TBI was necessary to induce stable mixed chimerism, but it could be obtained without the CP use. The percentage of CD3e/CD8a and Ly-49D/NK1.1 cells was significantly lower in the groups of mice treated by corresponding antibodies. Moreover, we observed the lowest number of peripheral blood Ly-49D/NK1.1 cells in the group of animals with highest mixed chimerism. Our experiments in mice model can help in better understanding of mixed chimerism phenomenon and in selecting the method of

  5. Advances in chimeric antigen receptor immunotherapy for neuroblastoma.

    PubMed

    Heczey, Andras; Louis, Chrystal U

    2013-12-01

    Neuroblastoma (NBL) is the most common extracranial pediatric solid tumor and has heterogeneous biology and behavior. Patients with high-risk disease have poor prognosis despite complex multimodal therapy; therefore, novel curative approaches are needed. Immunotherapy is a novel therapeutic approach that harnesses the inherent activity of the immune system to control and eliminate malignant cells. One form of immunotherapy uses chimeric antigen receptors (CAR) to target tumor-associated antigens. CARs are derived from the antigen-binding domain of a monoclonal antibody (MAb) coupled with the intracellular signaling portion of the T cell receptor. CARs can combine the specificity and effectiveness of MAbs with the active bio-distribution, direct cytotoxicity, and long-term persistence of T cells. NBL provides an attractive target for CAR immunotherapy as many of its tumor-associated antigens are not expressed at significant levels on normal tissues, thus decreasing potential treatment related toxicity. Two previous clinical trials utilizing L1-cell adhesion molecule (L1-CAM) and disialoganglioside (GD2) specific CARs (GD2-CAR) have demonstrated safety and anti-tumor efficacy in heavily pretreated relapsed/refractory neuroblastoma patients. Based on these promising results and on improved techniques that can further potentiate CAR therapies, two clinical trials are currently investigating the use of GD2-CARs in children with NBL. Several approaches may further enhance anti-tumor activity and persistence of CAR modified cells, and if these can be safely translated into the clinic, CAR-based immunotherapy could become a viable adjunct or potential alternative to conventional treatment options for patients with NBL. PMID:24333408

  6. Endosymbiotic gene transfer from prokaryotic pangenomes: Inherited chimerism in eukaryotes

    PubMed Central

    Ku, Chuan; Nelson-Sathi, Shijulal; Roettger, Mayo; Garg, Sriram; Hazkani-Covo, Einat; Martin, William F.

    2015-01-01

    Endosymbiotic theory in eukaryotic-cell evolution rests upon a foundation of three cornerstone partners—the plastid (a cyanobacterium), the mitochondrion (a proteobacterium), and its host (an archaeon)—and carries a corollary that, over time, the majority of genes once present in the organelle genomes were relinquished to the chromosomes of the host (endosymbiotic gene transfer). However, notwithstanding eukaryote-specific gene inventions, single-gene phylogenies have never traced eukaryotic genes to three single prokaryotic sources, an issue that hinges crucially upon factors influencing phylogenetic inference. In the age of genomes, single-gene trees, once used to test the predictions of endosymbiotic theory, now spawn new theories that stand to eventually replace endosymbiotic theory with descriptive, gene tree-based variants featuring supernumerary symbionts: prokaryotic partners distinct from the cornerstone trio and whose existence is inferred solely from single-gene trees. We reason that the endosymbiotic ancestors of mitochondria and chloroplasts brought into the eukaryotic—and plant and algal—lineage a genome-sized sample of genes from the proteobacterial and cyanobacterial pangenomes of their respective day and that, even if molecular phylogeny were artifact-free, sampling prokaryotic pangenomes through endosymbiotic gene transfer would lead to inherited chimerism. Recombination in prokaryotes (transduction, conjugation, transformation) differs from recombination in eukaryotes (sex). Prokaryotic recombination leads to pangenomes, and eukaryotic recombination leads to vertical inheritance. Viewed from the perspective of endosymbiotic theory, the critical transition at the eukaryote origin that allowed escape from Muller’s ratchet—the origin of eukaryotic recombination, or sex—might have required surprisingly little evolutionary innovation. PMID:25733873

  7. Endosymbiotic gene transfer from prokaryotic pangenomes: Inherited chimerism in eukaryotes.

    PubMed

    Ku, Chuan; Nelson-Sathi, Shijulal; Roettger, Mayo; Garg, Sriram; Hazkani-Covo, Einat; Martin, William F

    2015-08-18

    Endosymbiotic theory in eukaryotic-cell evolution rests upon a foundation of three cornerstone partners--the plastid (a cyanobacterium), the mitochondrion (a proteobacterium), and its host (an archaeon)--and carries a corollary that, over time, the majority of genes once present in the organelle genomes were relinquished to the chromosomes of the host (endosymbiotic gene transfer). However, notwithstanding eukaryote-specific gene inventions, single-gene phylogenies have never traced eukaryotic genes to three single prokaryotic sources, an issue that hinges crucially upon factors influencing phylogenetic inference. In the age of genomes, single-gene trees, once used to test the predictions of endosymbiotic theory, now spawn new theories that stand to eventually replace endosymbiotic theory with descriptive, gene tree-based variants featuring supernumerary symbionts: prokaryotic partners distinct from the cornerstone trio and whose existence is inferred solely from single-gene trees. We reason that the endosymbiotic ancestors of mitochondria and chloroplasts brought into the eukaryotic--and plant and algal--lineage a genome-sized sample of genes from the proteobacterial and cyanobacterial pangenomes of their respective day and that, even if molecular phylogeny were artifact-free, sampling prokaryotic pangenomes through endosymbiotic gene transfer would lead to inherited chimerism. Recombination in prokaryotes (transduction, conjugation, transformation) differs from recombination in eukaryotes (sex). Prokaryotic recombination leads to pangenomes, and eukaryotic recombination leads to vertical inheritance. Viewed from the perspective of endosymbiotic theory, the critical transition at the eukaryote origin that allowed escape from Muller's ratchet--the origin of eukaryotic recombination, or sex--might have required surprisingly little evolutionary innovation. PMID:25733873

  8. Faith-based perspectives on the use of chimeric organisms for medical research.

    PubMed

    Degeling, Chris; Irvine, Rob; Kerridge, Ian

    2014-04-01

    Efforts to advance our understanding of neurodegenerative diseases involve the creation chimeric organisms from human neural stem cells and primate embryos--known as prenatal chimeras. The existence of potential mentally complex beings with human and non-human neural apparatus raises fundamental questions as to the ethical permissibility of chimeric research and the moral status of the creatures it creates. Even as bioethicists find fewer reasons to be troubled by most types of chimeric organisms, social attitudes towards the non-human world are often influenced by religious beliefs. In this paper scholars representing eight major religious traditions provide a brief commentary on a hypothetical case concerning the development and use of prenatal human-animal chimeric primates in medical research. These commentaries reflect the plurality and complexity within and between religious discourses of our relationships with other species. Views on the moral status and permissibility of research on neural human animal chimeras vary. The authors provide an introduction to those who seek a better understanding of how faith-based perspectives might enter into biomedical ethics and public discourse towards forms of biomedical research that involves chimeric organisms. PMID:24293125

  9. Low dose busulfan facilitates chimerism and tolerance in a murine model.

    PubMed

    Anam, Khairul; Black, Alfred T; Hale, Douglas A

    2006-01-01

    T cell depletion, sirolimus and "mega" dose donor specific bone marrow (DSBM) infusion promotes stable multilineage chimerism and indefinite survival of skin allografts in completely mismatched mice. The purpose of this study is to determine whether the addition of low dose busulfan can reduce the amount of DSBM required while preserving efficacy. C57BL/6 recipients of BALB/c skin allografts were treated with alphaCD4 and alphaCD8 monoclonal antibodies, DSBM, sirolimus and various doses of busulfan. The kinetics and phenotype of chimerism and the presence of clonal deletion of alloreactive T-cells were defined using flow cytometry. In vitro reactivity was determined using mixed lymphocyte culture. Second skin grafts confirmed the presence of tolerance. All doses of busulfan resulted in engraftment when combined with this regimen using a reduced dose of donor marrow. The level, kinetics and character of chimerism observed were dose related. Chimerism was associated with indefinite allograft acceptance (>200 days). Tolerance was documented both in vitro/in vivo and was associated with clonal deletion. Addition of a single low dose of busulfan to an established tolerance protocol reduced the required DSBM dose by over 80% while still promoting comparable levels of donor chimerism and donor-specific tolerance. PMID:16431286

  10. Recognition of base pair inversions in duplex by chimeric (alpha,beta) triplex-forming oligonucleotides.

    PubMed

    Timofeev, Edward N; Goryaeva, Baira V; Florentiev, Vladimir L

    2006-10-01

    DNA recognition by triplex-forming oligonucleotides (TFOs) is usually limited by homopurine-homopyrimidine sequence in duplexes. Modifications of the third strand may overcome this limitation. Chimeric alpha-beta TFOs are expected to form triplex DNA upon binding to non-regular sequence duplexes. In the present study we describe binding properties of chimeric alpha-beta oligodeoxynucleotides in the respect to short DNA duplexes with one, three, and five base pair inversions. Non-natural chimeric TFO's contained alpha-thymidine residues inside (GT) or (GA) core sequences. Modified residues were addressed to AT/TA inversions in duplexes. It was found in the non-denaturing gel-electrophoresis experiments that single or five adjacent base pair inversions in duplexes may be recognized by chimeric alpha-beta TFO's at 10 degrees C and pH 7.8. Three dispersed base pair inversions in the double stranded DNA prevented triplex formation by either (GT) or (GA) chimeras. Estimation of thermal stability of chimeric alpha-beta triplexes showed decrease in T(m) values as compared with unmodified complexes. PMID:16928141

  11. Immunomodulatory Effects of Mixed Hematopoietic Chimerism: Immune Tolerance in Canine Model of Lung Transplantation

    PubMed Central

    Nash;, Richard A.; Yunosov;, Murad; Abrams;, Kraig; Hwang;, Billanna; Castilla-Llorente;, Cristina; Chen;, Peter; Farivar;, Alexander S.; Georges;, George E.; Hackman;, Robert C.; Lamm;, Wayne J.E.; Lesnikova;, Marina; Ochs;, Hans D.; Randolph-Habecker;, Julie; Ziegler;, Stephen F.; Storb;, Rainer; Storer;, Barry; Madtes;, David K.; Glenny;, Robb; Mulligan, Michael S.

    2010-01-01

    Long-term survival after lung transplantation is limited by acute and chronic graft rejection. Induction of immune tolerance by first establishing mixed hematopoietic chimerism (MC) is a promising strategy to improve outcomes. In a preclinical canine model, stable MC was established in recipients after reduced-intensity conditioning and hematopoietic cell transplantation from a DLA-identical donor. Delayed lung transplantation was performed from the stem cell donor without pharmacological immunosuppression. Lung graft survival without loss of function was prolonged in chimeric (n=5) vs. nonchimeric (n=7) recipients (p≤0.05, Fisher’s test). There were histological changes consistent with low grade rejection in 3/5 of the lung grafts in chimeric recipients at ≥1 year. Chimeric recipients after lung transplantation had a normal immune response to a T-dependent antigen. Compared to normal dogs, there were significant increases of CD4+INFγ+, CD4+IL-4+ and CD8+ INFγ+ T-cell subsets in the blood (p <0.0001 for each of the 3 T-cell subsets). Markers for regulatory T-cell subsets including foxP3, IL10 and TGFβ were also increased in CD3+ T cells from the blood and peripheral tissues of chimeric recipients after lung transplantation. Establishing MC is immunomodulatory and observed changes were consistent with activation of both the effector and regulatory immune response. PMID:19422333

  12. Theoretical design of a new chimeric protein for the treatment of breast cancer.

    PubMed

    Soleimani, Meysam; Mahnam, Karim; Mirmohammad-Sadeghi, Hamid; Sadeghi-Aliabadi, Hojjat; Jahanian-Najafabadi, Ali

    2016-01-01

    p28 and NRC peptides are two anticancer peptides with various mechanisms have shown to be effective against breast cancer. Therefore, it seems that construction of a chimeric protein containing the two peptides might cause synergistic cytotoxic effects. However, since the two peptides bear opposite charges, production of a chimeric protein in which the two moieties do not intervene each other is difficult. In this study, our goal was to find a suitable peptide linker for the new chimeric protein in a manner that none of the peptides intervene the other's function. We selected some linkers with different characteristics and lengths and created a small library of the chimeric proteins harboring these linkers. Homology modeling and molecular dynamic simulation revealed that (PA)5P and (EAAAK)3 linkers can separate the p28 and NRC peptides effectively. Thus, the chimeric protein linked with (PA)5P or (EAAAK)3 linkers might show synergistic and stronger anticancer effects than the separate peptide moieties because they could exert their cytotoxic effects freely which is not influenced by the other part. PMID:27499788

  13. Gamma-irradiation depletes endogenous germ cells and increases donor cell distribution in chimeric chickens.

    PubMed

    Park, Kyung Je; Kang, Seok Jin; Kim, Tae Min; Lee, Young Mok; Lee, Hyung Chul; Song, Gwonhwa; Han, Jae Yong

    2010-12-01

    The production of chimeric birds is an important tool for the investigation of vertebrate development, the conservation of endangered birds, and the development of various biotechnological applications. This study examined whether gamma (γ)-irradiation depletes endogenous primordial germ cells and enhances the efficiency of somatic chimerism in chickens. An optimal irradiation protocol for stage X embryos was determined after irradiation at various doses (0, 100, 300, 500, 600, 700, and 2,000 rad). Exposure to 500 rad of γ-irradiation for 73 s significantly decreased the number of primordial germ cells (P < 0.0001). Somatic chimera hatchlings were then produced by transferring blastodermal cells from a Korean Oge into either an irradiated (at 500 rad) or intact stage X White Leghorn embryo. An analysis of feather color pattern and polymerase chain reaction-based species-specific amplification of various tissues of the hatchlings confirmed chimerism in most organs of the chick produced from the irradiated recipient; a lesser degree of chimerism was observed in the non-irradiated control recipient. In conclusion, the exposure of chick embryos to an optimized dose of γ-irradiation effectively depleted germ cells and yielded greater somatic chimerism than non-irradiated control embryos. This technique can be applied to interspecies reproduction or the production of transgenic birds. PMID:21057980

  14. Theoretical design of a new chimeric protein for the treatment of breast cancer

    PubMed Central

    Soleimani, Meysam; Mahnam, Karim; Mirmohammad-Sadeghi, Hamid; Sadeghi-Aliabadi, Hojjat; Jahanian-Najafabadi, Ali

    2016-01-01

    p28 and NRC peptides are two anticancer peptides with various mechanisms have shown to be effective against breast cancer. Therefore, it seems that construction of a chimeric protein containing the two peptides might cause synergistic cytotoxic effects. However, since the two peptides bear opposite charges, production of a chimeric protein in which the two moieties do not intervene each other is difficult. In this study, our goal was to find a suitable peptide linker for the new chimeric protein in a manner that none of the peptides intervene the other’s function. We selected some linkers with different characteristics and lengths and created a small library of the chimeric proteins harboring these linkers. Homology modeling and molecular dynamic simulation revealed that (PA)5P and (EAAAK)3 linkers can separate the p28 and NRC peptides effectively. Thus, the chimeric protein linked with (PA)5P or (EAAAK)3 linkers might show synergistic and stronger anticancer effects than the separate peptide moieties because they could exert their cytotoxic effects freely which is not influenced by the other part. PMID:27499788

  15. Generation and evaluation of a chimeric classical swine fever virus expressing a visible marker gene.

    PubMed

    Li, Yongfeng; Wang, Xiao; Sun, Yuan; Li, Lian-Feng; Zhang, Lingkai; Li, Su; Luo, Yuzi; Qiu, Hua-Ji

    2016-03-01

    Classical swine fever virus (CSFV) is a noncytopathogenic virus, and the incorporation of an enhanced green fluorescent protein (EGFP) tag into the viral genome provides a means of direct monitoring of viral infection without immunostaining. It is well established that the 3' untranslated region (3'-UTR) of the CSFV plays an important role in viral RNA replication. Although CSFV carrying a reporter gene and chimeric CSFV have been generated and evaluated, a chimeric CSFV with a visible marker has not yet been reported. Here, we generated and evaluated a chimeric virus containing the EGFP tag and the 3'-UTR from vaccine strain HCLV (C-strain) in the genetic background of the highly virulent CSFV Shimen strain. The chimeric marker CSFV was fluorescent and had an approximately 100-fold lower viral titer, lower replication level of viral genome, and weaker fluorescence intensity than the recombinant CSFV with only the EGFP tag or the parental virus. Furthermore, the marker chimera was avirulent and displayed no viremia in inoculated pigs, which were completely protected from lethal CSFV challenge as early as 15 days post-inoculation. The chimeric marker virus was visible in vitro and attenuated in vitro and in vivo, which suggests that CSFV can be engineered to produce attenuated variants with a visible marker to facilitate in vitro studies of CSFV infection and replication and to develop of novel vaccines against CSF. PMID:26614259

  16. Chimeric spider silk proteins mediated by intein result in artificial hybrid silks.

    PubMed

    Lin, Senzhu; Chen, Gefei; Liu, Xiangqin; Meng, Qing

    2016-07-01

    Hybrid silks hold a great potential as specific biomaterials due to its controlled mechanical properties. To produce fibers with tunable properties, here we firstly made chimeric proteins in vitro, called W2C4CT and W2C8CT, with ligation of MaSp repetitive modules (C) with AcSp modules (W) by intein trans splicing technology from smaller precursors without final yield reduction. Intein mediated chimeric proteins form fibers at a low concentration of 0.4 mg/mL in 50 mM K3 PO4 pH 7.5 just drawn by hand. Hybrid fibers show smoother surface, and also have stronger chemical resistance as compared with fibers from W2CT (W fibers) and mixture of W2CT/C8CT (MHF8 fibers). Fibers from chimeric protein W2C4CT (HFH4) have improved mechanical properties than W fibers; however, with more C modules W2C8CT fibers (HFH8) properties decreased, indicates the length proportion of various modules is very important and should be optimized for fibers with specific properties. Generally, hybrid silks generated via chimeric proteins, which can be simplified by intein trans splicing, has greater potential to produce fibers with tunable properties. Our research shows that intein mediated directional protein ligation is a novel way to make large chimeric spider silk proteins and hybrid silks. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 385-392, 2016. PMID:26948769

  17. [Successful treatment with rituximab in a patient with splenic marginal zone B-cell lymphoma accompanied by cold agglutinin disease].

    PubMed

    Yasuyama, Masako; Kawauchi, Kiyotaka; Otsuka, Kuniaki; Tamura, Hiroyuki; Fujibayashi, Mariko

    2014-01-01

    An 81-year-old man was admitted to our hospital due to dyspnea in July 2008. A physical examination revealed marked splenomegaly, and the results of laboratory tests were as follows: hemoglobin (Hb)=7.0 g/dL, Ret=6.4%, WBC=24,100/μL (Ly: 20,003/μL), indirect bilirubin=3.6 mg/dL, LDH=232 IU/L. The cold agglutinin titer was 1 : 8,192, and a direct antiglobulin test was positive. A PET scan showed abnormal accumulation in the spleen and bone marrow. A bone marrow aspirate examination and biopsy demonstrated diffuse involvement of abnormal lymphocytes that were found to be positive for CD20 and negative for CD5, CD10, and cyclin D1. The immunoglobulin genes were clonally rearranged. Based on these findings, splenic marginal zone B-cell lymphoma (SMZL) associated with cold agglutinin disease (CAD) was diagnosed. Because the patient refused splenectomy, he was treated with four cycles of rituximab therapy (375 mg/kg, once a week). The Hb level and lymphocyte count subsequently normalized and the splenomegaly resolved. One year later, he relapsed and was again treated with rituximab therapy with complete remission. CAD accompanied by SMZL is very rare. Rituximab may be chosen as an alternative and effective therapeutic option in patients with SMZL-particularly those with autoimmune hemolytic anemia. PMID:25749330

  18. Phase II trial of weekly bortezomib in combination with rituximab in untreated patients with Waldenström Macroglobulinemia.

    PubMed

    Ghobrial, Irene M; Xie, Wanling; Padmanabhan, Swaminathan; Badros, Ashraf; Rourke, Meghan; Leduc, Renee; Chuma, Stacey; Kunsman, Janet; Warren, Diane; Poon, Tiffany; Harris, Brianna; Sam, Amy; Anderson, Kenneth C; Richardson, Paul G; Treon, Steven P; Weller, Edie; Matous, Jeffrey

    2010-09-01

    This study aimed to determine the activity and safety of weekly bortezomib and rituximab in patients with untreated Waldenström Macroglobulinemia (WM). Patients with no prior therapy and symptomatic disease were eligible. Patients received bortezomib IV weekly at 1.6 mg/m(2) on days 1, 8, 15, q 28 days × 6 cycles, and rituximab 375 mg/m(2) weekly on cycles 1 and 4. Primary endpoint was the percent of patients with at least a minor response (MR). Twenty-six patients were treated. At least MR was observed in 23/26 patients (88%) (95% CI: 70-98%) with 1 complete response (4%), 1 near-complete response (4%), 15 partial remission (58%), and 6 MR (23%). Using IgM response evaluated by nephlometry, all 26 patients (100%) achieved at least MR or better. The median time to progression has not been reached, with an estimated 1-year event free rate of 79% (95% CI: 53, 91%). Common grade 3 and 4 therapy related adverse events included reversible neutropenia in 12%, anemia in 8%, and thrombocytopenia in 8%. No grade 3 or 4 neuropathy occurred. The combination of weekly bortezomib and rituximab exhibited significant activity and minimal neurological toxicity in patients with untreated WM. PMID:20652865

  19. Clinical experience with lenalidomide alone or in combination with rituximab in indolent B-cell and mantle cell lymphomas.

    PubMed

    Ruan, J; Shah, B; Martin, P; Schuster, S J

    2016-07-01

    Lenalidomide is an oral immunomodulatory drug with significant activity in indolent B-cell and mantle cell lymphomas. Lenalidomide has a manageable safety profile whether administered as a single agent or in combination with rituximab. The combination of lenalidomide with rituximab, known as the 'R(2)' regimen, enhances efficacy over what has been shown with monotherapy and has demonstrated activity in patients considered resistant to rituximab. Tolerability of these regimens has been consistent among studies. Asymptomatic neutropenia is the most common grade 3/4 adverse event, typically managed by dose interruption, followed by dose reduction once neutrophils have recovered. Nonhematologic toxicities (e.g. fatigue) are generally low-grade, manageable with concomitant treatment, and/or lenalidomide dose modification. More frequent with R(2), immune-related symptoms such as rash and tumor flare are important to recognize as lenalidomide-associated treatment effects in patients with lymphoma who require supportive care and potential dose modifications. Severe tumor flare reactions with painful lymphadenopathy are not typically observed outside of chronic lymphocytic leukemia/small lymphocytic lymphoma. Venous thromboembolism is uncommon in lymphomas, though prophylaxis is recommended. The general safety profile, differences between lenalidomide monotherapy and R(2) treatment, and optimal strategies for managing adverse events are discussed here. PMID:27052651

  20. Low-Dose Rituximab Therapy for Antibody-Mediated Rejection in a Highly Sensitized Heart-Transplant Recipient

    PubMed Central

    Aggarwal, Ashim; Pyle, Joseph; Hamilton, John; Bhat, Geetha

    2012-01-01

    Antibody-mediated rejection is the B-cell–mediated production of immunoglobulin G antibody against the transplanted heart. The currently available therapies for antibody-mediated rejection have had marginal success, and chronic manifestations of rejection can result in an increased risk of graft vasculopathy and perhaps require repeat transplantation. Rituximab, a monoclonal antibody directed against the CD20 receptor of B-lymphocytes and approved as therapy for lymphoma, can be used in heart-transplant patients for the management of antibody-mediated rejection. We present the case of a 52-year-old woman with high allosensitization (pre-transplantation panel reactive antibody level, 72%) who underwent successful orthotopic heart transplantation. Postoperatively, her acute antibody-mediated rejection with concomitant cellular rejection was successfully treated with low-dose rituximab. The patient died 5 months later because of multiple other medical problems. The present case suggests a role for low-dose rituximab as therapy for antibody-mediated rejection in heart-transplant patients. PMID:23304051

  1. CD20-Targeting Immunotherapy Promotes Cellular Senescence in B-Cell Lymphoma.

    PubMed

    Däbritz, J Henry M; Yu, Yong; Milanovic, Maja; Schönlein, Martin; Rosenfeldt, Mathias T; Dörr, Jan R; Kaufmann, Andreas M; Dörken, Bernd; Schmitt, Clemens A

    2016-05-01

    The CD20-targeting monoclonal antibody rituximab is an established component of immunochemotherapeutic regimens against B-cell lymphomas, where its coadministration with conventional anticancer agents has significantly improved long-term outcome. However, the cellular mechanisms by which rituximab exerts its antilymphoma activity are only partially understood. We show here that rituximab induces typical features of cellular senescence, a long-term growth arrest of viable cells with distinct biologic properties, in established B-cell lymphoma cell lines as well as primary transformed B cells. In addition, rituximab-based immunotherapy sensitized lymphoma cells to senescence induction by the chemotherapeutic compound adriamycin (a.k.a. doxorubicin), and, to a lesser extent, by the antimicrotubule agent vincristine. Anti-CD20 treatment further enhanced secretion of senescence-associated cytokines, and augmented the DNA damage response signaling cascade triggered by adriamycin. As the underlying prosenescence mechanism, we found intracellular reactive oxygen species (ROS) levels to be elevated in response to rituximab, and, in turn, the ROS scavenger N-acetylcysteine to largely abrogate rituximab-mediated senescence. Our results, further supported by gene set enrichment analyses in a clinical data set of chronic lymphocytic leukemia patient samples exposed to a rituximab-containing treatment regimen, provide important mechanistic insights into the biologic complexity of anti-CD20-evoked tumor responses, and unveil cellular senescence as a hitherto unrecognized effector principle of the antibody component in lymphoma immunochemotherapy. Mol Cancer Ther; 15(5); 1074-81. ©2016 AACR. PMID:26880268

  2. Rituximab extended schedule or retreatment trial for low tumour burden non-follicular indolent B-cell non-Hodgkin lymphomas: Eastern Cooperative Oncology Group Protocol E4402.

    PubMed

    Williams, Michael E; Hong, Fangxin; Gascoyne, Randy D; Wagner, Lynne I; Krauss, John C; Habermann, Thomas M; Swinnen, Lode J; Schuster, Stephen J; Peterson, Christopher G; Sborov, Mark D; Martin, S Eric; Weiss, Matthias; Ehmann, W Christopher; Horning, Sandra J; Kahl, Brad S

    2016-06-01

    The rituximab extended schedule or retreatment trial (RESORT; E4402) was a phase 3 randomized prospective trial comparing maintenance rituximab (MR) versus a retreatment (RR) dosing strategy in asymptomatic, low tumour burden indolent lymphoma. A planned exploratory sub-study compared the two strategies for small lymphocytic (SLL) and marginal zone lymphomas (MZL). Patients responding to rituximab weekly × 4 were randomized to MR (single dose rituximab every 3 months until treatment failure) or RR (rituximab weekly × 4) at the time of each progression until treatment failure. The primary endpoint was time to treatment failure (TTTF). Patients with SLL (n = 57), MZL (n = 71) and unclassifiable small B-cell lymphoma (n = 3) received induction rituximab. The overall response rate (ORR) was 40% [95% confidence interval (CI) 31-49%; SLL ORR 22·8%; MZL ORR 52·1%]; all 52 responders were randomized. At a median of 4·3 years from randomization, treatment failure occurred in 18/23 RR and 15/29 MR. The median TTTF was 1·4 years for RR and 4·8 years for MR (P = 0·012); median time to first cytotoxic therapy was 6·3 years for RR and not reached for MR (P = 0·0002). Survival did not differ (P = 0·72). In low tumour burden SLL and MZL patients responding to rituximab induction, MR significantly improved TTTF as compared with RR. PMID:26970533

  3. Impact of dose intensity on outcome of fludarabine, cyclophosphamide, and rituximab regimen given in the first-line therapy for chronic lymphocytic leukemia

    PubMed Central

    Bouvet, Emmanuelle; Borel, Cécile; Obéric, Lucie; Compaci, Gisèle; Cazin, Bruno; Michallet, Anne-Sophie; Laurent, Guy; Ysebaert, Loic

    2013-01-01

    Fludarabine-cyclophosphamide-rituximab is the most efficient first-line treatment for chronic lymphocytic leukemia patients. Many dose adjustments of the original MD Anderson Cancer Center regimen have been proposed. However, whether fludarabine-cyclophosphamide-rituximab relative dose intensity may have an impact on outcome has not yet been investigated. We retrospectively assessed relative dose intensity in 106 community-based patients included in our regional healthcare network from 2004-11, all receiving fludarabine-cyclophosphamide-rituximab as first-line treatment outside clinical trials. Dose reductions were observed in 51.4% of patients, mainly decided by the individual physician and not based on recommendations (52.7%), while there were fewer reports of toxicity or dose reduction because of impaired renal function. Progression-free survival was significantly reduced in patients who had a reduction in dose intensity of more than 20% in fludarabine-cyclophosphamide and/or rituximab. Multivariate analysis showed dose of rituximab had a significant impact on minimal residual disease and progression-free survival. Although prophylactic granulocyte-colony stimulating factor significantly reduced the rate of grade 3-4 neutropenia and febrile neutropenia, it had no impact on relative dose intensity and outcome. This study shows that, in routine clinical practice, there is low adherence to the original MD Anderson Cancer Center fludarabine-cyclophosphamide-rituximab schedule, and that the decision to modify dosage was mostly taken by the individual physician and was based on anticipated toxicity. This study shows that reduction of fludarabine-cyclophosphamide and, more importantly, of rituximab doses seriously interferes with progression-free survival. PMID:23065520

  4. Efficacy and safety of front-line therapy with fludarabine-cyclophosphamide-rituximab regimen for chronic lymphocytic leukemia outside clinical trials: the Israeli CLL Study Group experience.

    PubMed

    Herishanu, Yair; Goldschmidt, Neta; Bairey, Osnat; Ruchlemer, Rosa; Fineman, Riva; Rahimi-Levene, Naomi; Shvidel, Lev; Tadmor, Tamar; Ariel, Aviv; Braester, Andrea; Shapiro, Mika; Joffe, Erel; Polliack, Aaron

    2015-05-01

    This study aimed to evaluate the efficacy and safety of the fludarabine-cyclophosphamide-rituximab regimen for young physically fit patients with chronic lymphocytic leukemia in the "real-life" setting. We specifically focused on the impact of dose reduction on patient outcomes. The patient cohort consisted of 128 patients with chronic lymphocytic leukemia (≤ 70 years) treated at 10 Israeli centers with front-line fludarabine-cyclophosphamide-rituximab. We defined reduced chemotherapy as two-thirds or less of the total indicated dose. Patients treated with rituximab were divided into two groups and compared: those who received full dosages of 375 mg/m(2) or 500 mg/m(2), and patients given less than six cycles with either dose. Overall and clinical complete response rates (92.8% and 70.4%), as well as toxicities and overall survival (median not reached at 6 years), were similar to other reported clinical trials, but progression-free survival was shorter (42.5 months). Almost 50% of patients had some dose reduction of chemotherapy, 21% receiving less than two-thirds of the indicated dose, while close to 30% did not complete six cycles of rituximab. Reduced doses of chemotherapy and rituximab were independently associated with shorter progression-free survival (hazard ratio 3.6, P<0.0001 for reduced chemotherapy; hazard ratio 2.5, P=0.003 for incomplete-treatment with rituximab). Achieving a complete response was associated with longer overall survival but was not linked to the given dose of chemoimmunotherapy. In younger physically fit patients, front-line fludarabine-cyclophosphamide-rituximab therapy in the "real-life" setting achieves long remissions (albeit shorter than in clinical trials) and prolonged overall survival. However, dose reductions are commonly administered and may impact outcome. PMID:25661442

  5. Impact of Fc gamma-receptor polymorphisms on the response to rituximab treatment in children and adolescents with mature B cell lymphoma/leukemia.

    PubMed

    Burkhardt, Birgit; Yavuz, Deniz; Zimmermann, Martin; Schieferstein, Jutta; Kabickova, Edita; Attarbaschi, Andishe; Lisfeld, Jasmin; Reiter, Alfred; Makarova, Olga; Worch, Jennifer; Bonn, Bettina R; Damm-Welk, Christine

    2016-09-01

    Recent studies in adult lymphoma patients have indicated a correlation between polymorphisms of Fc gamma-receptors (FcγRs, encoded by the respective FCGR genes) and the response to rituximab treatment. In vitro, cells expressing FcγRIIIa-158V mediate antibody-dependent cellular cytotoxicity (ADCC) more efficiently than cells expressing FcγRIIIa-158F. The impact of the FCGR2A-131HR polymorphism is unclear. In this study, the FCGR polymorphisms FCGR3A-158VF and FCGR2A-131HR were analyzed in pediatric patients with mature aggressive B cell non-Hodgkin lymphoma/leukemia (B-NHL). Pediatric patients received a single dose of rituximab monotherapy. Response was evaluated on day 5 followed by standard chemotherapy for B-NHL. Among 105 evaluable patients, a response to rituximab was observed in 21 % of those homozygous for FcγRIIa-131RR (5/24) compared to 48 % of patients who were HH and HR FcγRIIa-131 allele carriers (18/34 and 21/47, respectively; p = 0.044). Among patients with the FCGR3A-158 polymorphism, those homozygous for the FF genotype had a significantly favorable rituximab response rate of 59 % (22/37) compared to 32 % in patients who were FcγRIIIa-158VV and FcγRIIIa-VF allele carriers (2/9 and 20/59, respectively; p = 0.022). A stringent phase II response evaluation of children and adolescents with B-NHL after one dose of rituximab monotherapy showed a significant association between the rituximab response rate and FCGR polymorphisms. These findings support the hypothesis that FCGR polymorphisms represent patient-specific parameters that influence the response to rituximab. PMID:27376362

  6. CHIMERIC SINDBIS/EASTERN EQUINE ENCEPHALITIS VACCINE CANDIDATES ARE HIGHLY ATTENUATED AND IMMUNOGENIC IN MICE

    PubMed Central

    Wang, Eryu; Petrakova, Olga; Adams, A. Paige; Aguilar, Patricia V.; Kang, Wenli; Paessler, Slobodan; Volk, Sara M.; Frolov, Ilya; Weaver, Scott C.

    2007-01-01

    We developed chimeric Sindbis (SINV)/Eastern equine encephalitis (EEEV) viruses and investigated their potential for use as live virus vaccines against EEEV. One vaccine candidate contained structural protein genes from a typical North American EEEV strain, while the other had structural proteins from a naturally attenuated Brazilian isolate. Both chimeric viruses replicated efficiently in mammalian and mosquito cell cultures and were highly attenuated in mice. Vaccinated mice did not develop detectable disease or viremia, but developed high titers of neutralizing antibodies. Upon challenge with EEEV, mice vaccinated with >104PFU of the chimeric viruses were completely protected from disease. These findings support the potential use of these SIN/EEEV chimeras as safe and effective vaccines. PMID:17904699

  7. Biosimilar monoclonal antibodies in lymphoma: a critical appraisal.

    PubMed

    Rioufol, Catherine; Salles, Gilles

    2015-05-01

    Rituximab, an anti-CD20 monoclonal antibody, revolutionized the treatment of lymphoma. Although newer generation anti-CD20 monoclonal antibodies are being examined, patent expiries and patient demand have fueled the development of rituximab biosimilars. The development of such agents is both an important and difficult undertaking. By definition, although they aim to have safety and efficacy comparable with their reference agents, biosimilars are not exact replicas of those agents, and small changes in nonclinical and preclinical properties may ultimately affect in vivo activity. Consideration must be given to the complex mechanisms of action, sensitive patient populations that may be treated, and appropriate clinical trial endpoints. Furthermore, extrapolation of indications is multifaceted, deserving close examination. This review represents a critical look at biosimilars in lymphoma and their safety, efficacy and long-term effects on patient outcomes. PMID:25818308

  8. In vitro and in vivo properties of human/mouse chimeric monoclonal antibody specific for common acute lymphocytic leukemia antigen

    SciTech Connect

    Saga, T.; Endo, K.; Koizumi, M.; Kawamura, Y.; Watanabe, Y.; Konishi, J.; Ueda, R.; Nishimura, Y.; Yokoyama, M.; Watanabe, T. )

    1990-06-01

    A human/mouse chimeric monoclonal antibody specific for a common acute lymphocytic leukemia antigen was efficiently obtained by ligating human heavy-chain enhancer element to the chimeric heavy- and light-chain genes. Cell binding and competitive inhibition assays of both radioiodine and indium-111- (111In) labeled chimeric antibodies demonstrated in vitro immunoreactivity identical with that of the parental murine monoclonal antibodies. The biodistribution of the radiolabeled chimeric antibody in tumor-bearing nude mice was similar to that of the parental murine antibody. Tumor accumulation of radioiodinated parental and chimeric antibodies was lower than that of {sup 111}In-labeled antibodies, probably because of dehalogenation of the radioiodinated antibodies. Indium-111-labeled chimeric antibody clearly visualized xenografted tumor. These results suggest that a human/mouse chimeric antibody can be labeled with {sup 111}In and radioiodine without the loss of its immunoreactivity, and that chimeric antibody localizes in vivo in the same way as the parental murine antibody.

  9. Silkworms transformed with chimeric silkworm/spider silk genes spin composite silk fibers with improved mechanical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of a spider silk manufacturing process is of great interest. piggyBac vectors were used to create transgenic silkworms encoding chimeric silkworm/spider silk proteins. The silk fibers produced by these animals were composite materials that included chimeric silkworm/spider silk prote...

  10. Structure-Function Analysis of Peroxisomal ATP-binding Cassette Transporters Using Chimeric Dimers*

    PubMed Central

    Geillon, Flore; Gondcaille, Catherine; Charbonnier, Soëli; Van Roermund, Carlo W.; Lopez, Tatiana E.; Dias, Alexandre M. M.; Pais de Barros, Jean-Paul; Arnould, Christine; Wanders, Ronald J.; Trompier, Doriane; Savary, Stéphane

    2014-01-01

    ABCD1 and ABCD2 are two closely related ATP-binding cassette half-transporters predicted to homodimerize and form peroxisomal importers for fatty acyl-CoAs. Available evidence has shown that ABCD1 and ABCD2 display a distinct but overlapping substrate specificity, although much remains to be learned in this respect as well as in their capability to form functional heterodimers. Using a cell model expressing an ABCD2-EGFP fusion protein, we first demonstrated by proximity ligation assay and co-immunoprecipitation assay that ABCD1 interacts with ABCD2. Next, we tested in the pxa1/pxa2Δ yeast mutant the functionality of ABCD1/ABCD2 dimers by expressing chimeric proteins mimicking homo- or heterodimers. For further structure-function analysis of ABCD1/ABCD2 dimers, we expressed chimeric dimers fused to enhanced GFP in human skin fibroblasts of X-linked adrenoleukodystrophy patients. These cells are devoid of ABCD1 and accumulate very long-chain fatty acids (C26:0 and C26:1). We checked that the chimeric proteins were correctly expressed and targeted to the peroxisomes. Very long-chain fatty acid levels were partially restored in transfected X-linked adrenoleukodystrophy fibroblasts regardless of the chimeric construct used, thus demonstrating functionality of both homo- and heterodimers. Interestingly, the level of C24:6 n-3, the immediate precursor of docosahexaenoic acid, was decreased in cells expressing chimeric proteins containing at least one ABCD2 moiety. Our data demonstrate for the first time that both homo- and heterodimers of ABCD1 and ABCD2 are functionally active. Interestingly, the role of ABCD2 (in homo- and heterodimeric forms) in the metabolism of polyunsaturated fatty acids is clearly evidenced, and the chimeric dimers provide a novel tool to study substrate specificity of peroxisomal ATP-binding cassette transporters. PMID:25043761

  11. Yellow Fever/Japanese Encephalitis Chimeric Viruses: Construction and Biological Properties

    PubMed Central

    Chambers, Thomas J.; Nestorowicz, Ann; Mason, Peter W.; Rice, Charles M.

    1999-01-01

    A system has been developed for generating chimeric yellow fever/Japanese encephalitis (YF/JE) viruses from cDNA templates encoding the structural proteins prM and E of JE virus within the backbone of a molecular clone of the YF17D strain. Chimeric viruses incorporating the proteins of two JE strains, SA14-14-2 (human vaccine strain) and JE Nakayama (JE-N [virulent mouse brain-passaged strain]), were studied in cell culture and laboratory mice. The JE envelope protein (E) retained antigenic and biological properties when expressed with its prM protein together with the YF capsid; however, viable chimeric viruses incorporating the entire JE structural region (C-prM-E) could not be obtained. YF/JE(prM-E) chimeric viruses grew efficiently in cells of vertebrate or mosquito origin compared to the parental viruses. The YF/JE SA14-14-2 virus was unable to kill young adult mice by intracerebral challenge, even at doses of 106 PFU. In contrast, the YF/JE-N virus was neurovirulent, but the phenotype resembled parental YF virus rather than JE-N. Ten predicted amino acid differences distinguish the JE E proteins of the two chimeric viruses, therefore implicating one or more residues as virus-specific determinants of mouse neurovirulence in this chimeric system. This study indicates the feasibility of expressing protective antigens of JE virus in the context of a live, attenuated flavivirus vaccine strain (YF17D) and also establishes a genetic system for investigating the molecular basis for neurovirulence determinants encoded within the JE E protein. PMID:10074160

  12. Functionalization of scaffolds with chimeric anti-BMP-2 monoclonal antibodies for osseous regeneration

    PubMed Central

    Ansari, Sahar; Moshaverinia, Alireza; Pi, Sung Hee; Han, Alexander; Abdelhamid, Alaa I.; Zadeh, Homayoun H.

    2013-01-01

    Recent studies have demonstrated the ability of murine anti-BMP-2 monoclonal antibodies (mAb) immobilized on an absorbable collagen sponge (ACS) to mediate de novo bone formation, a process termed antibody mediated osseous regeneration (AMOR). The objectives of this study were to assess the efficacy of a newly generated chimeric anti-BMP-2 mAb in mediating AMOR, as well as to evaluate the suitability of different biomaterials as scaffolds to participate in AMOR. Chimeric anti-BMP-2 mAb was immobilized on 4 biomaterials, namely, titanium microbeads (Ti), alginate hydrogel, macroporous biphasic calcium phosphate (MBCP) and ACS, followed by surgical implantation into rat critical-size calvarial defects. Animals were sacrificed after 8 weeks and the degree of bone fill was assessed using micro-CT and histomorphometry. Results demonstrated local persistence of chimeric anti-BMP-2 mAb up to 8 weeks, as well as significant de novo bone regeneration in sites implanted with chimeric anti-BMP-2 antibody immobilized on each of the 4 scaffolds. Ti and MBCP showed the highest volume of bone regeneration, presumably due to their resistance to compression. Alginate and ACS also mediated de novo bone formation, though significant volumetric shrinkage was noted. In vitro assays demonstrated cross-reactivity of chimeric anti-BMP-2 mAb with BMP-4 and BMP-7. Immune complex of anti-BMP-2 mAb with BMP-2 induced osteogenic differentiation of C2C12 cells in vitro, involving expression of RUNX2 and phosphorylation of Smad1. The present data demonstrated the ability of chimeric anti- BMP-2 mAb to functionalize different biomaterial with varying characteristics to mediate osteogenesis. PMID:24055525

  13. Generation and Developmental Characteristics of Porcine Tetraploid Embryos and Tetraploid/diploid Chimeric Embryos

    PubMed Central

    He, Wenteng; Kong, Qingran; Shi, Yongqian; Xie, Bingteng; Jiao, Mingxia; Huang, Tianqing; Guo, Shimeng; Hu, Kui; Liu, Zhonghua

    2013-01-01

    The aim of this study was to optimize electrofusion conditions for generating porcine tetraploid (4n) embryos and produce tetraploid/diploid (4n/2n) chimeric embryos. Different electric field intensities were tested and 2 direct current (DC) pulses of 0.9 kV/cm for 30 μs was selected as the optimum condition for electrofusion of 2-cell embryos to produce 4n embryos. The fusion rate of 2-cell embryos and the development rate to blastocyst of presumably 4n embryos, reached 85.4% and 28.5%, respectively. 68.18% of the fused embryos were found to be 4n as demonstrated by fluorescent in situ hybridization (FISH). Although the number of blastomeres in 4n blastocysts was significantly lower than in 2n blastocysts (P < 0.05), there was no significant difference in developmental rates of blastocysts between 2n and 4n embryos (P > 0.05), suggesting that the blastocyst forming capacity in 4n embryos is similar to those in 2n embryos. Moreover, 4n/2n chimeric embryos were obtained by aggregation of 4n and 2n embryos. We found that the developmental rate and cell number of blastocysts of 4-cell (4n)/4-cell (2n) chimeric embryos were significantly higher than those of 2-cell (4n)/4-cell (2n), 4-cell (4n)/8-cell (2n), 4-cell (4n)/2-cell (2n) chimeric embryos (P < 0.05). Consistent with mouse chimeras, the majority of 4n cells contribute to the trophectoderm (TE), while the 2n cells are mainly present in the inner cell mass (ICM) of porcine 4n/2n chimeric embryos. Our study established a feasible and efficient approach to produce porcine 4n embryos and 4n/2n chimeric embryos. PMID:24120753

  14. Interspecies chimeric complementation for the generation of functional human tissues and organs in large animal hosts.

    PubMed

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-01

    The past decade's rapid progress in human pluripotent stem cell (hPSC) research has generated hope for meeting the rising demand of organ donation, which remains the only effective cure for end-stage organ failure, a major cause of death worldwide. Despite the potential, generation of transplantable organs from hPSCs using in vitro differentiation is far-fetched. An in vivo interspecies chimeric complementation strategy relying on chimeric-competent hPSCs and zygote genome editing provides an auspicious alternative for providing unlimited organ source for transplantation. PMID:26820411

  15. Low absolute lymphocyte count and addition of rituximab confer high risk for interstitial pneumonia in patients with diffuse large B-cell lymphoma.

    PubMed

    Huang, Yu-Chung; Liu, Chia-Jen; Liu, Chun-Yu; Pai, Jih-Tung; Hong, Ying-Chung; Teng, Hao-Wei; Hsiao, Liang-Tsai; Chao, Ta-Chung; Gau, Jyh-Pyng; Liu, Jin-Hwang; Hsu, Hui-Chi; Chiou, Tzeon-Jye; Chen, Po-Min; Yu, Yuan-Bin; Tzeng, Cheng-Hwai

    2011-10-01

    Several small-scale studies have reported pulmonary toxicity among patients with diffuse large B-cell lymphoma (DLBCL) receiving rituximab-containing chemotherapy, though whether the use of rituximab predisposes to interstitial pneumonia (IP) remains unclear. This retrospective study was intended to identify the characteristics and risk factors of IP in patients with DLBCL. Between 2000 and 2009, 529 consecutive patients with DLBCL receiving first-line tri-weekly COP- or CHOP-based chemotherapy with or without rituximab were enrolled as subjects. IP was defined as diffuse pulmonary interstitial infiltrates found on computed tomography scans in conjunction with respiratory symptoms. IP was observed in 26 patients (4.9%), six of whom were confirmed with Pneumocystis jirovecii pneumonia. The median number of chemotherapy courses before IP was four cycles. Using multivariate analysis, absolute lymphocyte count less than 1×10(9)/l at diagnosis [odds ratio (OR) 2.75, p=0.014] and the addition of rituximab to chemotherapy (OR 4.56, p=0.003) were identified as independent risk factors for IP. In conclusion, the incidence of IP is increased in patients with DLBCL receiving rituximab-containing chemotherapy. Specific subgroups with lymphopenia at diagnosis may justify close scrutiny to detect pulmonary complications. PMID:21647583

  16. Rituximab is a safe and effective long-term treatment for children with steroid and calcineurin inhibitor-dependent idiopathic nephrotic syndrome.

    PubMed

    Ravani, Pietro; Ponticelli, Alessandro; Siciliano, Chiara; Fornoni, Alessia; Magnasco, Alberto; Sica, Felice; Bodria, Monica; Caridi, Gianluca; Wei, Changli; Belingheri, Mirco; Ghio, Luciana; Merscher-Gomez, Sandra; Edefonti, Alberto; Pasini, Andrea; Montini, Giovanni; Murtas, Corrado; Wang, Xiangyu; Muruve, Daniel; Vaglio, Augusto; Martorana, Davide; Pani, Antonello; Scolari, Francesco; Reiser, Jochen; Ghiggeri, Gian M

    2013-11-01

    In children with idiopathic nephrotic syndrome, rituximab can maintain short-term remission with withdrawal of prednisone and calcineurin inhibitors. Long-term effects including the number of repeated infusions to maintain remission are unknown. To test this, we treated 46 consecutive children with idiopathic nephrotic syndrome lasting for at least 1 year (mean 6.3 years), maintained in remission with oral prednisone and calcineurin inhibitors. They received 1-5 rituximab courses during a median follow-up of 3 years. Oral agents were tapered after each infusion, and completely withdrawn within 45 days. Rituximab was well tolerated. Six-month probabilities of remission were 48% after the first infusion and 37% after subsequent infusions. One- and 2-year-remission probabilities were, respectively, 20 and 10%. Median time intervals between complete oral-agent withdrawal and relapse were 5.6 and 8.5 months, respectively, following the first and subsequent courses. The time to reconstitution of CD20 cells correlated with the duration of remission, but was not associated with variation in FcyR, CD20, or SMPDL-3B polymorphisms. Podocyte Src phosphorylation was normal. Thus, rituximab can be safely and repeatedly used as a prednisone and calcineurin inhibitor-sparing therapy in a considerable proportion of children with dependent forms of idiopathic nephrotic syndrome. Further study is needed to identify patients who will benefit most from rituximab therapy. PMID:23739238

  17. Tubular and endothelial chimerism in renal allografts using fluorescence and chromogenic in situ hybridization (FISH, CISH) technology.

    PubMed

    Varga, Zsuzsanna; Gaspert, Ariana; Behnke, Silvia; von Teichman, Adriana; Fritzsche, Florian; Fehr, Thomas

    2012-04-01

    The role of endothelial and tubular chimerism in renal allograft adaptation and rejection varies in different studies. We addressed the correlation between different clinico-pathological settings and sex-chromosomal endothelial and/or tubular chimerism in renal allografts. We examined the presence or absence of the X and Y chromosomes by fluorescence and chromogenic in situ hybridization (FISH, CISH) methodology on paraffin embedded kidney biopsies in 16 gender mismatched renal transplants (1 to 12 years post-transplantation). Twelve patients were male, four female. Four groups were selected: (i) Vascular calcineurin inhibitor toxicity without rejection; (ii) T-cell mediated vascular rejection; (iii) antibody mediated rejection; and (iv) C4d-positivity in AB0-incompatible transplants with or without rejection. Twelve non-transplant kidney biopsies (8 female, 4 male) were used as controls. Tubular chimerism was detected more frequently (69%) than endothelial chimerism (12%) in renal transplants. One of 12 control patients had tubular and endothelial chimeric cells (8%). The Y chromosome occurred in 8/12 male recipients (67%) in tubular epithelial cells and in 5/12 male recipients (42%) in endothelial cells. Double X chromosomes were detected in 3/4 female recipients in tubular epithelium. Tubular chimerism occurred more often with endothelial chimerism and capillaritis without correlation with other parameters, such as rejection. Combined Y chromosomal tubular and lymphatic endothelial chimerism correlated with T-cell mediated vascular rejection in two out of three patients (66%). Combined Y chromosomal tubular and peritubular capillary chimerism correlated with antibody mediated C4d+ rejection in one out of two patients (50%). Tubular and/or endothelial chimerism occur frequently in gender mismatched renal allografts and, when combined, this is associated with T-cell mediated rejection. PMID:22449229

  18. Immunologic effects of rituximab on the human spleen in immune thrombocytopenia

    PubMed Central

    Audia, Sylvain; Samson, Maxime; Guy, Julien; Janikashvili, Nona; Fraszczak, Jennifer; Trad, Malika; Ciudad, Marion; Leguy, Vanessa; Berthier, Sabine; Petrella, Tony; Aho-Glélé, Serge; Martin, Laurent; Maynadié, Marc; Lorcerie, Bernard; Rat, Patrick; Cheynel, Nicolas; Katsanis, Emmanuel; Larmonier, Nicolas

    2011-01-01

    Immune thrombocytopenia (ITP) is an autoimmune disease with a complex pathogenesis. As in many B cell–related autoimmune diseases, rituximab (RTX) has been shown to increase platelet counts in some ITP patients. From an immunologic standpoint, the mode of action of RTX and the reasons underlying its limited efficacy have yet to be elucidated. Because splenectomy is a cornerstone treatment of ITP, the immune effect of RTX on this major secondary lymphoid organ was investigated in 18 spleens removed from ITP patients who were treated or not with RTX. Spleens from ITP individuals had follicular hyperplasia consistent with secondary follicles. RTX therapy resulted in complete B-cell depletion in the blood and a significant reduction in splenic B cells, but these patients did not achieve remission. Moreover, whereas the percentage of circulating regulatory T cells (Tregs) was similar to that in controls, splenic Tregs were reduced in ITP patients. Interestingly, the ratio of proinflammatory Th1 cells to suppressive Tregs was increased in the spleens of patients who failed RTX therapy. These results indicate that although B cells are involved in ITP pathogenesis, RTX-induced total B-cell depletion is not correlated with its therapeutic effects, which suggests additional immune-mediated mechanisms of action of this drug. PMID:21876120

  19. Cladribine plus rituximab is an effective therapy for newly diagnosed mantle cell lymphoma.

    PubMed

    Spurgeon, Stephen E; Pindyck, Talia; Okada, Craig; Chen, Yiyi; Chen, Zunqiu; Mater, Elana; Abbi, Kamal; Epner, Elliot M

    2011-08-01

    Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma that is incurable with standard chemotherapy. There is no consensus on the best initial therapy, especially for elderly patients, who are not candidates for aggressive treatment approaches. Current National Comprehensive Cancer Network (NCCN) treatment guidelines include rituximab (R) plus cladribine for the initial treatment of MCL. However, few data are available to substantiate this recommendation. Therefore, to further define the role of R-cladribine for the initial treatment of MCL, we performed a retrospective chart review of 31 patients with MCL (median age, 67) treated with R-cladribine. The majority of responding patients also received R maintenance. The overall response rate was 87%, with 61% of patients achieving a complete remission (CR/CRu). The estimated median follow-up was 32.5 months, median PFS was 37.5 months, and median OS was 85.2 months. One of 19 (5.3%) subjects in CR/CRu relapsed (median follow-up of 23 months). CR/CRu was associated with improved survival (p < 0.0001), while a high mantle cell international prognostic index (MIPI) was associated with worse survival (p = 0.05). There was one toxic death (neutropenic pseudomonal sepsis) related to treatment. R-cladribine is an effective therapy for previously untreated MCL, and these results validate the use of R-cladribine for the initial treatment of MCL. PMID:21623691

  20. [Rituximab (MabThera)--a new biological medicine in rheumatoid arthritis therapy].

    PubMed

    Nemec, P

    2007-11-01

    Rheumatoid arthritis (RA) is a serious, chronic, inflammatory disorder that damages the joints. The chronic destructive process causes pain to patients with RA and leads to the development of permanent disability. At present, great emphasis is placed on timely and effective therapy for RA, which is able to halt or slow the development of the disorder. At present we do not have any means of curing RA, the main objective for treatment is to induce remission of the disorder and prevent structural damage to the joints and the development of permanent disability. The relatively frequent failure of disease modifying medications (DMARDs) lead to efforts to find new resources for the treatment of RA. So called biological medicines were recently introduced into therapeutic use. These were mainly TNFalpha blockers. Experience has shown that approximately a third of patients with RA do not respond even to treatment with such medicines. Rituximab (MabThera), a monoclonal antibody against CD20 positive B-lymphocytes, is a new biological medicine approved for RA therapy. It represents a new hope for patients with active RA, for whom earlier therapy with TNFa blockers has failed. PMID:18277630

  1. Rituximab, cyclophosphamide-fractionated, vincristine, doxorubicin and dexamethasone alternating with rituximab, methotrexate and cytarabine overcomes risk features associated with inferior outcomes in treatment of newly diagnosed, high-risk diffuse large B-cell lymphoma.

    PubMed

    Mato, Anthony; Feldman, Tatyana; Zielonka, Tania; Singavi, Arun; Gadaletta, Gabriella; Waksmundzki, Kathryn; Bhattacharyya, Pritish; Chow, Kar Fai; Yang, Xiao; Panush, David; Agress, Harry; Rosario, Maria; Howlett, Christina; Pecora, Andrew; Goy, Andre

    2013-12-01

    Subtypes of diffuse large B-cell lymphoma (DLBCL) that have inferior outcomes after front-line therapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) have been identified. While it is agreed that R-CHOP is probably not adequate in these patients, there is no standard treatment approach for patients with DLBCL with high-risk features. We present results of a retrospective cohort study of high-risk DLBCL (defined as having at least one unfavorable risk factor: non-germinal center [GC] subtype by immunohistochemistry [IHC], Ki-67 ≥ 80%, high International Prognostic Index [IPI], c-MYC rearrangement) treated with R-HCVAD/R-MTX-AraC (rituximab, cyclophosphamide-fractionated, vincristine, doxorubicin and dexamethasone alternating with rituximab, methotrexate and cytarabine; R-HCVAD) as front-line therapy. With a median follow-up of 25.3 months, the 3-year PFS and OS estimates are 79% (95% confidence interval [CI], 65-88%) and 76% (95% CI, 61-86%), respectively, which are higher than those for historical comparisons with R-CHOP data for high-risk patients. These data are in accord with other recent reports of dose-intense front-line therapy of high-risk DLBCL. This analysis represents the largest reported cohort of patients with DLBCL treated with R-HCVAD. These data suggest that R-HCVAD can overcome traditional poor risk features such as high IPI, high Ki-67 and non-GC IHC pattern. Future work will focus on identifying molecular markers for failure in patients with DLBCL treated with dose-intensive regimens. PMID:23488604

  2. SAT Type Foot-and-Mouth Disease (FMD) Chimeric Vaccine Elicits Protection in Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent development of infectious cDNA clone technology for foot-and-mouth disease (FMD), Southern African Territories (SAT) viruses has provided a valuable tool for genetic and biological characterization of field and laboratory strains. Recombinant chimeric viruses, containing the capsid-coding...

  3. Alloreactive Regulatory T Cells Allow the Generation of Mixed Chimerism and Transplant Tolerance

    PubMed Central

    Ruiz, Paulina; Maldonado, Paula; Hidalgo, Yessia; Sauma, Daniela; Rosemblatt, Mario; Bono, Maria Rosa

    2015-01-01

    The induction of donor-specific transplant tolerance is one of the main goals of modern immunology. Establishment of a mixed chimerism state in the transplant recipient has proven to be a suitable strategy for the induction of long-term allograft tolerance; however, current experimental recipient preconditioning protocols have many side effects, and are not feasible for use in future therapies. In order to improve the current mixed chimerism induction protocols, we developed a non-myeloablative bone-marrow transplant (NM-BMT) protocol using retinoic acid (RA)-induced alloantigen-specific Tregs, clinically available immunosuppressive drugs, and lower doses of irradiation. We demonstrate that RA-induced alloantigen-specific Tregs in addition to a NM-BMT protocol generates stable mixed chimerism and induces tolerance to allogeneic secondary skin allografts in mice. Therefore, the establishment of mixed chimerism through the use of donor-specific Tregs rather than non-specific immunosuppression could have a potential use in organ transplantation. PMID:26635810

  4. Exploration of genetically encoded voltage indicators based on a chimeric voltage sensing domain

    PubMed Central

    Mishina, Yukiko; Mutoh, Hiroki; Song, Chenchen; Knöpfel, Thomas

    2014-01-01

    Deciphering how the brain generates cognitive function from patterns of electrical signals is one of the ultimate challenges in neuroscience. To this end, it would be highly desirable to monitor the activities of very large numbers of neurons while an animal engages in complex behaviors. Optical imaging of electrical activity using genetically encoded voltage indicators (GEVIs) has the potential to meet this challenge. Currently prevalent GEVIs are based on the voltage-sensitive fluorescent protein (VSFP) prototypical design or on the voltage-dependent state transitions of microbial opsins. We recently introduced a new VSFP design in which the voltage-sensing domain (VSD) is sandwiched between a fluorescence resonance energy transfer pair of fluorescent proteins (termed VSFP-Butterflies) and also demonstrated a series of chimeric VSD in which portions of the VSD of Ciona intestinalis voltage-sensitive phosphatase are substituted by homologous portions of a voltage-gated potassium channel subunit. These chimeric VSD had faster sensing kinetics than that of the native Ci-VSD. Here, we describe a new set of VSFPs that combine chimeric VSD with the Butterfly structure. We show that these chimeric VSFP-Butterflies can report membrane voltage oscillations of up to 200 Hz in cultured cells and report sensory evoked cortical population responses in living mice. This class of GEVIs may be suitable for imaging of brain rhythms in behaving mammalians. PMID:25324718

  5. Chimeric Ply187 endolysin kills Staphylococcus aureus more effectively than the parental enzyme.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peptidoglycan hydrolases are an effective new source of antimicrobials. A chimeric fusion protein of the Ply187 endopeptidase domain and LysK SH3b cell wall binding domain is a potent agent against Staphylococcus aureus in three functional assays....

  6. Reco