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Sample records for therapeutic antibody catumaxomab

  1. Immunological changes in the ascites of cancer patients after intraperitoneal administration of the bispecific antibody catumaxomab (anti-EpCAM×anti-CD3).

    Science.gov (United States)

    Fossati, Marco; Buzzonetti, Alexia; Monego, Giovanni; Catzola, Valentina; Scambia, Giovanni; Fattorossi, Andrea; Battaglia, Alessandra

    2015-08-01

    To explore the effects of intraperitoneal (i.p.) infusion of catumaxomab, a bispecific monoclonal antibody (anti-EpCAM×anti-CD3), on T cells, NK cells and macrophages in ascites of cancer patients and to understand how ascitic immune cells can be activated despite the pervasive immunosuppressive ability of ascites microenvironment. Six patients with malignant ascites received i.p. catumaxomab infusion. Ascitic immune cells were profiled by flow cytometry and gene expression at baseline and after i.p. catumaxomab infusion. In vitro experiments enabled investigations on the adverse effect of ascites microenvironment on catumaxomab-stimulated immune cells. I.p. catumaxomab infusion enhanced the expression of the CD69 and CD38 activation molecules in CD4(+) and CD8(+) T cells, NK cells and macrophages, and favoured CD8(+) T cell accumulation into the peritoneal cavity. An analogous immune cell activation as well as IFN-γ and IL-2 production were induced by catumaxomab in vitro. In vitro experiments showed that the immunosuppressive milieu of ascites abrogated all the immunostimulatory activities of catumaxomab. Adding EpCAM(+) tumour cells to the culture permitted both catumaxomab Fab regions to engage cognate antigens and restored immunostimulatory catumaxomab activity. This is the first demonstration in a clinical setting that i.p. catumaxomab infusion activates NK cells and macrophages in addition to T cells in ascites and favours CD8(+) T cell accumulation into the peritoneal cavity. Moreover, our findings indicate that the concomitant binding of both catumaxomab Fab regions delivers an activation signal that is strong enough to activate immune cells despite the prevailing immunosuppressive environment of malignant ascites. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. The trifunctional antibody catumaxomab for the treatment of malignant ascites due to epithelial cancer: Results of a prospective randomized phase II/III trial

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    Heiss, Markus M; Murawa, Pawel; Koralewski, Piotr; Kutarska, Elzbieta; Kolesnik, Olena O; Ivanchenko, Vladimir V; Dudnichenko, Alexander S; Aleknaviciene, Birute; Razbadauskas, Arturas; Gore, Martin; Ganea-Motan, Elena; Ciuleanu, Tudor; Wimberger, Pauline; Schmittel, Alexander; Schmalfeldt, Barbara; Burges, Alexander; Bokemeyer, Carsten; Lindhofer, Horst; Lahr, Angelika; Parsons, Simon L

    2010-01-01

    Malignant ascites is a common manifestation of advanced cancers, and treatment options are limited. The trifunctional antibody catumaxomab (anti-epithelial cell-adhesion molecule x anti-CD3) represents a targeted immunotherapy for the intraperitoneal (i.p.) treatment of malignant ascites secondary to epithelial cancers. In this phase II/III trial (EudraCT 2004-000723-15; NCT00836654), cancer patients (n = 258) with recurrent symptomatic malignant ascites resistant to conventional chemotherapy were randomized to paracentesis plus catumaxomab (catumaxomab) or paracentesis alone (control) and stratified by cancer type (129 ovarian and 129 nonovarian). Catumaxomab was administered as an i.p. infusion on Days 0, 3, 7 and 10 at doses of 10, 20, 50 and 150 μg, respectively. The primary efficacy endpoint was puncture-free survival. Secondary efficacy parameters included time to next paracentesis, ascites signs and symptoms and overall survival (OS). Puncture-free survival was significantly longer in the catumaxomab group (median 46 days) than the control group (median 11 days) (hazard ratio = 0.254: p < 0.0001) as was median time to next paracentesis (77 versus 13 days; p < 0.0001). In addition, catumaxomab patients had fewer signs and symptoms of ascites than control patients. OS showed a positive trend for the catumaxomab group and, in a prospectively planned analysis, was significantly prolonged in patients with gastric cancer (n = 66; 71 versus 44 days; p = 0.0313). Although adverse events associated with catumaxomab were frequent, they were manageable, generally reversible and mainly related to its immunologic mode of action. Catumaxomab showed a clear clinical benefit in patients with malignant ascites secondary to epithelial cancers, especially gastric cancer, with an acceptable safety profile. PMID:20473913

  3. Antibody Engineering and Therapeutics

    Science.gov (United States)

    Almagro, Juan Carlos; Gilliland, Gary L; Breden, Felix; Scott, Jamie K; Sok, Devin; Pauthner, Matthias; Reichert, Janice M; Helguera, Gustavo; Andrabi, Raiees; Mabry, Robert; Bléry, Mathieu; Voss, James E; Laurén, Juha; Abuqayyas, Lubna; Barghorn, Stefan; Ben-Jacob, Eshel; Crowe, James E; Huston, James S; Johnston, Stephen Albert; Krauland, Eric; Lund-Johansen, Fridtjof; Marasco, Wayne A; Parren, Paul WHI; Xu, Kai Y

    2014-01-01

    The 24th Antibody Engineering & Therapeutics meeting brought together a broad range of participants who were updated on the latest advances in antibody research and development. Organized by IBC Life Sciences, the gathering is the annual meeting of The Antibody Society, which serves as the scientific sponsor. Preconference workshops on 3D modeling and delineation of clonal lineages were featured, and the conference included sessions on a wide variety of topics relevant to researchers, including systems biology; antibody deep sequencing and repertoires; the effects of antibody gene variation and usage on antibody response; directed evolution; knowledge-based design; antibodies in a complex environment; polyreactive antibodies and polyspecificity; the interface between antibody therapy and cellular immunity in cancer; antibodies in cardiometabolic medicine; antibody pharmacokinetics, distribution and off-target toxicity; optimizing antibody formats for immunotherapy; polyclonals, oligoclonals and bispecifics; antibody discovery platforms; and antibody-drug conjugates. PMID:24589717

  4. Therapeutic Recombinant Monoclonal Antibodies

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    Bakhtiar, Ray

    2012-01-01

    During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

  5. A phase I trial of intravenous catumaxomab

    DEFF Research Database (Denmark)

    Mau-Sørensen, Morten; Dittrich, Christian; Dienstmann, Rodrigo

    2015-01-01

    . A reversible decrease in liver function test (prothrombin time) at the 7-µg dose level was considered a DLT. The first patient at 10 µg experienced a fatal hepatic failure related to catumaxomab that led to the termination of the study. CONCLUSIONS: The MTD of weekly intravenous catumaxomab was 7 µg. Major...... design in epithelial cancers with known EpCAM expression. The dose-limiting toxicity (DLT) period consisted of 4 weeks, with weekly intravenous administration of catumaxomab. Key DLTs were ≥grade 3 optimally treated non-hematological toxicity; ≥grade 3 infusion-related reactions refractory to supportive.......5 %). The most common TEAE of grade ≥3 was transient dose-dependent increases in aspartate aminotransferase (56.3 %). The intensity of toxicities decreased with the number of infusions. Also, serum IL-6 increased in a dose-dependent manner and reverted to low or undetectable levels after four infusions...

  6. Palliative treatment of malignant ascites: profile of catumaxomab

    Directory of Open Access Journals (Sweden)

    Lila Ammouri

    2010-05-01

    Full Text Available Lila Ammouri, Eric E PrommerMayo Clinic Hospice and Palliative Medicine Program, Mayo Clinic College of Medicine, Mayo Clinic Hospital, Scottsdale, AZ, USAAbstract: Malignant ascites is the abnormal accumulation of fluid in the peritoneal cavity associated with several intrapelvic and intra-abdominal malignancies. The development of ascites leads to significant symptoms and poor quality of life for the cancer patient. Available therapies for palliation include treatment of the underlying disease, but when there are no treatment options, the use of diuretics, implantation of drainage catheters, and surgical shunting techniques are considered. None of these symptom palliation options affect the course of disease. The development of trifunctional antibodies, which attach to specific overexpressed surface markers on tumor cells, and trigger an immune response leading to cytoreductive effects, represents a new approach to the management of malignant ascites. The purpose of this review is to highlight current therapies for malignant ascites and review data as to the effectiveness of a new trifunctional antibody, catumaxomab.Keywords: catumaxomab, ascites, trifunctional

  7. Avian Diagnostic and Therapeutic Antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, David Sherman [UND SMHS

    2012-12-31

    A number of infectious agents have the potential of causing significant clinical symptomology and even death, but dispite this, the number of incidence remain below the level that supports producing a vaccine. Therapeutic antibodies provide a viable treatment option for many of these diseases. We proposed that antibodies derived from West Nile Virus (WNV) immunized geese would be able to treat WNV infection in mammals and potential humans. We demonstrated that WNV specific goose antibodies are indeed successful in treating WNV infection both prophylactically and therapeutically in a golden hamster model. We demonstrated that the goose derived antibodies are non-reactogenic, i.e. do not cause an inflammatory response with multiple exposures in mammals. We also developed both a specific pathogen free facility to house the geese during the antibody production phase and a patent-pending purification process to purify the antibodies to greater than 99% purity. Therefore, the success of these study will allow a cost effective rapidly producible therapeutic toward clinical testing with the necessary infrastructure and processes developed and in place.

  8. Natural Killer (NK- and T-Cell Engaging Antibody-Derived Therapeutics

    Directory of Open Access Journals (Sweden)

    Christoph Stein

    2012-06-01

    Full Text Available Unmodified antibodies (abs have been successful in the treatment of hematologic malignancies, but less so for the treatment of solid tumors. They trigger anti-tumor effects through their Fc-domains, and one way to improve their efficacy is to optimize their interaction with the effectors through Fc-engineering. Another way to empower abs is the design of bispecific abs and related fusion proteins allowing a narrower choice of effector cells. Here we review frequently chosen classes of effector cells, as well as common trigger molecules. Natural Killer (NK- and T-cells are the most investigated populations in therapeutical approaches with bispecific agents until now. Catumaxomab, the first bispecific ab to receive drug approval, targets the tumor antigen Epithelial Cell Adhesion Molecule (EpCAM and recruits T-cells via a binding site for the cell surface protein CD3. The next generation of recombinant ab-derivatives replaces the broadly reactive Fc-domain by a binding domain for a single selected trigger. Blinatumomab is the first clinically successful member of this class, targeting cancer cells via CD19 and engaging T-cells by CD3. Other investigators have developed related recombinant fusion proteins to recruit effectors, such as NK-cells and macrophages. The first such agents currently in preclinical and clinical development will be discussed.

  9. Theranostics Using Antibodies and Antibody-Related Therapeutics

    NARCIS (Netherlands)

    Moek, Kirsten L; Giesen, Danique; Kok, Iris C; de Groot, Derk Jan A; Jalving, Mathilde; Fehrmann, Rudolf S N; Lub-de Hooge, Marjolijn N; Brouwers, Adrienne H; de Vries, Elisabeth G E

    In theranostics, radiolabeled compounds are used to determine a treatment strategy by combining therapeutics and diagnostics in the same agent. Monoclonal antibodies (mAbs) and antibody-related therapeutics represent a rapidly expanding group of cancer medicines. Theranostic approaches using these

  10. Potential therapeutic roles for antibody mixtures.

    Science.gov (United States)

    Raju, T Shantha; Strohl, William R

    2013-10-01

    With the enormous success of recombinant monoclonal antibodies (rMAbs) as human therapeutics, there are increasing efforts underway to explore new molecular entities that mimic rMAbs to replicate this huge success. In addition to naked intact rMAbs, antibody drug conjugates (ADCs), FAb and F(ab')2 fragments and also Fc fusion proteins have been developed and/or marketed as human therapeutics to treat different human diseases, including life-threatening diseases such as cancer. Several hundreds more intact rMAbs, ADCs, FAb, F(ab')2 fragments and Fc fusion proteins are currently undergoing human clinical trials. In addition to these molecules, new type of antibody fragments such as single-chain Fvs (scFvs), VH, scFv-Fc, scFv-CH, scFAb, scFv-zipper, diabodies, bispecific antibodies and similar types of constructs are also being investigated to be developed as human monotherapeutics. Further, there are quite a few current examples of combinations of biologics being developed. For example, currently, several biopharmaceutical companies are developing combinations of antibody mixtures as human therapeutics. Accordingly, the question posed here is whether it is time to consider the possibility of developing a broader range of combinations of therapeutic biologics. Combinations of small organic molecules have been successfully used as therapeutics for many years to treat many diseases, so the context of using polypharmacology to treat human diseases is not novel. For the past several decades, intravenous immunoglobulins have successfully been used in treating various autoimmune diseases. In this context, several biotechnology companies are exploring the use of combinations of antibody mixtures as human therapeutics. This editorial discusses these current efforts and the potential future role of antibody mixtures as human therapeutics.

  11. IgA as therapeutic antibody

    NARCIS (Netherlands)

    Leusen, Jeanette H W

    2015-01-01

    This review is focused on the promises of IgA as a new therapeutic antibody. For more than 30 years IgG molecules have been used in the clinic in the fields of oncology, hematology, auto immune diseases and infections. However, IgA might be a good alternative, since it recruits different effector

  12. Patent disclosure requirements for therapeutic antibody patents.

    Science.gov (United States)

    De Luca, Carmela; Trifonova, Anastassia

    2017-08-01

    Therapeutic antibodies have grown to become an important product class within the biopharmaceutical market. A prerequisite to their commercialization is adequate patent protection. Disclosure requirements and the types of claims available in different jurisdictions can impact the scope of protection available for antibodies. Areas covered: A comparative review of statutory bases, patent office practices and selected decisions in Canada, the United States and the United Kingdom related to disclosure requirements is provided. Expert opinion: Differences in disclosure requirements exist in different jurisdictions which can impact the type of claims obtained and their survival when attacked in litigation. Including a wide variety of claim types is a key strategy to ensuring therapeutic antibodies are adequately protected. Method of use claims may provide advantages and broader protection in some circumstances and should also be considered.

  13. Distinct Therapeutic Mechanisms of Tau Antibodies

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    Funk, Kristen E.; Mirbaha, Hilda; Jiang, Hong; Holtzman, David M.; Diamond, Marc I.

    2015-01-01

    Tauopathies are neurodegenerative diseases characterized by accumulation of Tau amyloids, and include Alzheimer disease and certain frontotemporal dementias. Trans-neuronal propagation of amyloid mediated by extracellular Tau may underlie disease progression. Consistent with this, active and passive vaccination studies in mouse models reduce pathology, although by unknown mechanisms. We previously reported that intracerebroventricular administration of three anti-Tau monoclonal antibodies (HJ8.5, HJ9.3, and HJ9.4) reduces pathology in a model overexpressing full-length mutant (P301S) human Tau. We now study effects of these three antibodies and a negative control antibody (HJ3.4) on Tau aggregate uptake into BV2 microglial-like cells and primary neurons. Antibody-independent Tau uptake into BV2 cells was blocked by heparin, consistent with a previously described role for heparan sulfate proteoglycans. Two therapeutic antibodies (HJ8.5 and HJ9.4) promoted uptake of full-length Tau fibrils into microglia via Fc receptors. Surprisingly, HJ9.3 promoted uptake of fibrils composed of the Tau repeat domain or Alzheimer disease-derived Tau aggregates, but failed to influence full-length recombinant Tau fibrils. Size fractionation of aggregates showed that antibodies preferentially promote uptake of larger oligomers (n ≥∼20-mer) versus smaller oligomers (n ∼10-mer) or monomer. No antibody inhibited uptake of full-length recombinant fibrils into primary neurons, but HJ9.3 blocked neuronal uptake of Tau repeat domain fibrils and Alzheimer disease-derived Tau. Antibodies thus have multiple potential mechanisms, including clearance via microglia and blockade of neuronal uptake. However these effects are epitope- and aggregate size-dependent. Establishing specific mechanisms of antibody activity in vitro may help in design and optimization of agents that are more effective in vivo. PMID:26126828

  14. Universal influenza virus vaccines and therapeutic antibodies.

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    Nachbagauer, R; Krammer, F

    2017-04-01

    Current influenza virus vaccines are effective when well matched to the circulating strains. Unfortunately, antigenic drift and the high diversity of potential emerging zoonotic and pandemic viruses make it difficult to select the right strains for vaccine production. This problem causes vaccine mismatches, which lead to sharp drops in vaccine effectiveness and long response times to manufacture matched vaccines in case of novel pandemic viruses. To provide an overview of universal influenza virus vaccines and therapeutic antibodies in preclinical and clinical development. PubMed and clinicaltrials.gov were used as sources for this review. Universal influenza virus vaccines that target conserved regions of the influenza virus including the haemagglutinin stalk domain, the ectodomain of the M2 ion channel or the internal matrix and nucleoproteins are in late preclinical and clinical development. These vaccines could confer broad protection against all influenza A and B viruses including drift variants and thereby abolish the need for annual re-formulation and re-administration of influenza virus vaccines. In addition, these novel vaccines would enhance preparedness against emerging influenza virus pandemics. Finally, novel therapeutic antibodies against the same conserved targets are in clinical development and could become valuable tools in the fight against influenza virus infection. Both universal influenza virus vaccines and therapeutic antibodies are potential future options for the control of human influenza infections. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  15. Antibody humanization methods for development of therapeutic applications.

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    Ahmadzadeh, Vahideh; Farajnia, Safar; Feizi, Mohammad Ali Hosseinpour; Nejad, Ramezan Ali Khavari

    2014-04-01

    Recombinant antibody technologies are rapidly becoming available and showing considerable clinical success. However, the immunogenicity of murine-derived monoclonal antibodies is restrictive in cancer immunotherapy. Humanized antibodies can overcome these problems and are considered to be a promising alternative therapeutic agent. There are several approaches for antibody humanization. In this article we review various methods used in the antibody humanization process.

  16. An epithelial cell adhesion molecule- and CD3-bispecific antibody plus activated T-cells can eradicate chemoresistant cancer stem-like pancreatic carcinoma cells in vitro.

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    Umebayashi, Masayo; Kiyota, Akifumi; Koya, Norihiro; Tanaka, Hiroto; Onishi, Hideya; Katano, Mitsuo; Morisaki, Takashi

    2014-08-01

    Cancer stem-like properties of various types of cancer, including pancreatic cancer, one of the most aggressive types, correlate with metastasis, invasion, and therapeutic resistance. More importantly, chemoresistance in cancer stem-like cells (CSLCs) is a critical problem for eradication of pancreatic cancer. Several cell surface markers, such as CD44 and epithelial cell adhesion molecule (EpCAM), are molecular targets on CSLCs of pancreatic carcinoma. In this study, we investigated whether catumaxomab, a clinical-grade bi-specific antibody that binds to both EpCAM on tumor cells and CD3 on T-cells, combined with activated T-cells can eliminate chemoresistant pancreatic CSLCs in vitro. Firstly, we established a CSLC line (MU-PK1) from human pancreatic carcinoma cells derived from a patient with chemoresistant and disseminated pancreatic cancer. These CSLCs were almost completely resistant to gemcitabine-mediated cytotoxicity up to a concentration of 10 μg/ml. The cells expressed high levels of CSLC markers (CD44 and EpCAM) and had significantly higher capacities for sphere formation, invasion, and aldehyde dehydrogenase-1 expression, which are associated with cancer stemness properties. We found that pre-treatment with catumaxomab and subsequent addition of interleukin-2/OKT3 activated autologous T-cells eliminated CSLCs during a short incubation period. Moreover, when MU-PK1 cells were cultured under hypoxic conditions, the CSLCs became more aggressive. However, the combination of cytokine-activated killer T-cells with catumaxomab successfully lysed almost all these cells. In conclusion, catumaxomab combined with activated T-cells may be a potent therapeutic modality to eradicate chemoresistant pancreatic CSLCs. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  17. [A therapeutic Trojan horse: intracellular antibodies].

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    Teillaud, J L

    1999-10-01

    Intracellular immunization is a novel therapeutic approach based on intracellular expression of recombinant antibody fragments, either Fab or single chain Fv (scFv generated by the assembly of the VH with the VL region), targeted to the desired cell compartment (cytosol, nucleus, endoplasmic reticulum ...) using appropriate targeting sequences. Due to their exquisite specificity, these intracellular antibodies can be used to neutralize or modulate the functional activity of the target molecule. Intracellular immunization strategies currently under investigation in the field of oncology are directed against mutated oncogenic molecules such as ErbB-2, p21ras, and p53, as well as against apoptosis-inhibiting molecules such as Bcl-2. The first Phase I clinical trials on intracellular immunization are under way in the United States.

  18. Therapeutic Antibodies to Ganglioside GD2 Evolved from Highly Selective Germline Antibodies

    Directory of Open Access Journals (Sweden)

    Eric Sterner

    2017-08-01

    Full Text Available Antibodies play a crucial role in host defense and are indispensable research tools, diagnostics, and therapeutics. Antibody generation involves binding of genomically encoded germline antibodies followed by somatic hypermutation and in vivo selection to obtain antibodies with high affinity and selectivity. Understanding this process is critical for developing monoclonal antibodies, designing effective vaccines, and understanding autoantibody formation. Prior studies have found that antibodies to haptens, peptides, and proteins evolve from polyspecific germline antibodies. The immunological evolution of antibodies to mammalian glycans has not been studied. Using glycan microarrays, protein microarrays, cell binding studies, and molecular modeling, we demonstrate that therapeutic antibodies to the tumor-associated ganglioside GD2 evolved from highly specific germline precursors. The results have important implications for developing vaccines and monoclonal antibodies that target carbohydrate antigens. In addition, they demonstrate an alternative pathway for antibody evolution within the immune system that is distinct from the polyspecific germline pathway.

  19. Antibody therapeutics - the evolving patent landscape.

    Science.gov (United States)

    Petering, Jenny; McManamny, Patrick; Honeyman, Jane

    2011-09-01

    The antibody patent landscape has evolved dramatically over the past 30 years, particularly in areas of technology relating to antibody modification to reduce immunogenicity in humans or improve antibody function. In some cases antibody techniques that were developed in the 1980s are still the subject of patent protection in the United States or Canada. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Bispecific antibodies: design, therapy, perspectives

    Directory of Open Access Journals (Sweden)

    Sedykh SE

    2018-01-01

    Full Text Available Sergey E Sedykh, Victor V Prinz, Valentina N Buneva, Georgy A Nevinsky Laboratory of Repair Enzymes, Siberian Branch of Russian Academy of Sciences Institute of Chemical Biology and Fundamental Medicine, Novosibirsk State University, Novosibirsk, Russia Abstract: Antibodies (Abs containing two different antigen-binding sites in one molecule are called bispecific. Bispecific Abs (BsAbs were first described in the 1960s, the first monoclonal BsAbs were generated in the 1980s by hybridoma technology, and the first article describing the therapeutic use of BsAbs was published in 1992, but the number of papers devoted to BsAbs has increased significantly in the last 10 years. Particular interest in BsAbs is due to their therapeutic use. In the last decade, two BsAbs – catumaxomab in 2009 and blinatumomab in 2014, were approved for therapeutic use. Papers published in recent years have been devoted to various methods of BsAb generation by genetic engineering and chemical conjugation, and describe preclinical and clinical trials of these drugs in a variety of diseases. This review considers diverse BsAb-production methods, describes features of therapeutic BsAbs approved for medical use, and summarizes the prospects of practical application of promising new BsAbs. Keywords: bispecific antibodies, therapeutic antibodies, monoclonal antibodies

  1. The state-of-play and future of antibody therapeutics.

    Science.gov (United States)

    Elgundi, Zehra; Reslan, Mouhamad; Cruz, Esteban; Sifniotis, Vicki; Kayser, Veysel

    2017-12-01

    It has been over four decades since the development of monoclonal antibodies (mAbs) using a hybridoma cell line was first reported. Since then more than thirty therapeutic antibodies have been marketed, mostly as oncology, autoimmune and inflammatory therapeutics. While antibodies are very efficient, their cost-effectiveness has always been discussed owing to their high costs, accumulating to more than one billion dollars from preclinical development through to market approval. Because of this, therapeutic antibodies are inaccessible to some patients in both developed and developing countries. The growing interest in biosimilar antibodies as affordable versions of therapeutic antibodies may provide alternative treatment options as well potentially decreasing costs. As certain markets begin to capitalize on this opportunity, regulatory authorities continue to refine the requirements for demonstrating quality, efficacy and safety of biosimilar compared to originator products. In addition to biosimilars, innovations in antibody engineering are providing the opportunity to design biobetter antibodies with improved properties to maximize efficacy. Enhancing effector function, antibody drug conjugates (ADC) or targeting multiple disease pathways via multi-specific antibodies are being explored. The manufacturing process of antibodies is also moving forward with advancements relating to host cell production and purification processes. Studies into the physical and chemical degradation pathways of antibodies are contributing to the design of more stable proteins guided by computational tools. Moreover, the delivery and pharmacokinetics of antibody-based therapeutics are improving as optimized formulations are pursued through the implementation of recent innovations in the field. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Receptor antibodies as novel therapeutics for diabetes

    DEFF Research Database (Denmark)

    Ussar, Siegfried; Vienberg, Sara Gry; Kahn, C Ronald

    2011-01-01

    Antibodies to receptors can block or mimic hormone action. Taking advantage of receptor isoforms, co-receptors, and other receptor modulating proteins, antibodies and other designer ligands can enhance tissue specificity and provide new approaches to the therapy of diabetes and other diseases....

  3. Glypican-3 antibodies: a new therapeutic target for liver cancer

    OpenAIRE

    Ho, Mingqian Feng, Mitchell

    2013-01-01

    Glypican-3 (GPC3) is an emerging therapeutic target in hepatocellular carcinoma (HCC), even though the biological function of GPC3 remains elusive. Currently human (MDX-1414 and HN3) and humanized mouse (GC33 and YP7) antibodies that target GPC3 for HCC treatment are under different stages of preclinical or clinical development. Humanized mouse antibody GC33 is being evaluated in a phase II clinical trial. Human antibodies MDX-1414 and HN3 are under different stages of preclinical evaluation....

  4. Monoclonal antibodies: A review of therapeutic applications and ...

    African Journals Online (AJOL)

    The increasing demand for monoclonal antibodies (mAbs) used for diagnostic and therapeutic applications has led to the development of large scale manufacturing processes, with improvements in production achieved through continuous optimization of the inherent systems. The number of monoclonal antibodies (mAbs) ...

  5. Production of therapeutic antibodies in plants.

    Science.gov (United States)

    Nölke, Greta; Fischer, Rainer; Schillberg, Stefan

    2003-10-01

    Antibodies are versatile tools for the diagnosis and treatment of many diseases. Their use has increased dramatically with the advent of recombinant antibody (rAb) technology, allowing the production of immunological reagents with improved and novel properties. The main challenge now lies in achieving cost-effective production on a large scale. Over the past 15 years, the potential of plants for the production of pharmaceutical proteins has become well-established. Plants represent an inexpensive, efficient and safe alternative to traditional systems used for the commercial-scale synthesis of rAbs. This review describes the current status of antibody production in plants, focusing on their advantages compared with other expression systems and the remaining obstacles to widespread acceptance.

  6. Improving the targeting of therapeutics with single-domain antibodies.

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    Turner, Kendrick B; Alves, Nathan J; Medintz, Igor L; Walper, Scott A

    2016-01-01

    The targeted delivery of therapeutic agents greatly increases their effectiveness while simultaneously reducing negative side effects. In the past, targeting of therapeutics has been accomplished with nucleic acids, peptides/proteins, and conventional antibodies. A promising alternative to the conventional antibodies often used in therapeutic targeting are significantly smaller-sized antibody fragments known as single-domain antibodies (sdAbs). Recent advances in the utility of sdAbs for targeting of therapeutic agents along with relevant examples from the literature are discussed. Their advantages when compared to other targeting strategies as well as their challenges and limitations is also covered. The development of sdAb-based targeted therapeutics will likely continue. The identification of novel protein modification techniques will provide more options for sdAb modification (conjugation, immobilization, functionalization), allowing a wider array of therapeutic agents to be successfully targeted and delivered using sdAbs. This will also spur the selection of sdAbs with specificity for other targets having relevance towards therapeutics.

  7. Therapeutic antibodies as a treatment option for dengue fever.

    Science.gov (United States)

    Chan, Kuan Rong; Ong, Eugenia Z; Ooi, Eng Eong

    2013-11-01

    Dengue fever is the most prevalent mosquito-borne viral disease globally with about 100 million cases of acute dengue annually. Severe dengue infection can result in a life-threatening illness. In the absence of either a licensed vaccine or antiviral drug against dengue, therapeutic antibodies that neutralize dengue virus (DENV) may serve as an effective medical countermeasure against severe dengue. However, therapeutic antibodies would need to effectively neutralize all four DENV serotypes. It must not induce antibody-dependent enhancement of DENV infection in monocytes/macrophages through Fc gamma receptor (FcγR)-mediated phagocytosis, which is hypothesized to increase the risk of severe dengue. Here, we review the strategies and technologies that can be adopted to develop antibodies for therapeutic applications. We also discuss the mechanism of antibody neutralization in the cells targeted by DENV that express Fc gamma receptor. These studies have provided significant insight toward the use of therapeutic antibodies as a potentially promising bulwark against dengue.

  8. New structural formats of therapeutic antibodies for rheumatology.

    Science.gov (United States)

    Dumet, Christophe; Pottier, Jérémy; Gouilleux, Valérie; Watier, Hervé

    2018-01-01

    Pharmaceutical companies strive continuously to develop better medications in order to remain competitive. In the arena of monoclonal antibodies and related biologics (fusion proteins containing an IgG Fc fragment), the thrust is not only toward identifying new targets, but also toward developing new molecular formats. Here, new-generation antibodies used to treat rheumatic diseases are discussed, with emphasis on relations linking structure to pharmacological effects and on the improvements expected from the new formats. Isotypic and allotypic antibody diversity has pharmacological implications and is already exploited in commercially available antibodies. Efforts to engineer the Fc fragment of the various immunoglobulin G subclasses are reviewed with reference to abatacept, ixekizumab, other mutated IgG4 antibodies currently in development, sapelizumab, anifrolumab, and tanezumab. Bispecific antibodies are a focus of increasing interest (particularly those binding to both IL-17 and TNFα) and may earn a place in the therapeutic armamentarium as a means of avoiding the use of antibody combinations. However, the construction and production of bispecific antibodies continues to raise major technological challenges. Other molecular formats involve the fusion of antibodies to cytokines or the use of nanobodies and peptibodies. These new formats are at the very early stages of development, and their clinical relevance remains unclear. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  9. DISTINCT ANTIBODY SPECIES: STRUCTURAL DIFFERENCES CREATING THERAPEUTIC OPPORTUNITIES

    Science.gov (United States)

    Muyldermans, Serge; Smider, Vaughn V.

    2016-01-01

    Antibodies have been a remarkably successful class of molecules for binding a large number of antigens in therapeutic, diagnostic, and research applications. Typical antibodies derived from mouse or human sources use the surface formed by complementarity determining regions (CDRs) on the variable regions of the heavy chain/light chain heterodimer, which typically forms a relatively flat binding surface. Alternative species, particularly camelids and bovines, provide a unique paradigm for antigen recognition through novel domains which form the antigen binding paratope. For camelids, heavy chain antibodies bind antigen with only a single heavy chain variable region, in the absence of light chains. In bovines, ultralong CDR-H3 regions form an independently folding minidomain, which protrudes from the surface of the antibody and is diverse in both its sequence and disulfide patterns. The atypical paratopes of camelids and bovines potentially provide the ability to interact with different epitopes, particularly recessed or concave surfaces, compared to traditional antibodies. PMID:26922135

  10. Frontier of therapeutic antibody discovery: The challenges and how to face them

    OpenAIRE

    Lu, Zhi-Jian; Deng, Su-Jun; Huang, Da-Gang; He, Yun; Lei, Ming; Zhou, Li; Jin, Pei

    2012-01-01

    Therapeutic monoclonal antibodies have become an important class of modern medicines. The established technologies for therapeutic antibody discovery such as humanization of mouse antibodies, phage display of human antibody libraries and transgenic animals harboring human IgG genes have been practiced successfully so far, and many incremental improvements are being made constantly. These methodologies are responsible for currently marketed therapeutic antibodies and for the biopharma industry...

  11. Monoclonal Antibodies as Prophylactic and Therapeutic Agents Against Chikungunya Virus.

    Science.gov (United States)

    Clayton, April M

    2016-12-15

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is responsible for considerable epidemics worldwide and recently emerged in the Americas in 2013. CHIKV may cause long-lasting arthralgia after acute infection. With currently no licensed vaccines or antivirals, the design of effective therapies to prevent or treat CHIKV infection is of utmost importance and will be facilitated by increased understanding of the dynamics of chikungunya. In this article, monoclonal antibodies against CHIKV as viable prophylactic and therapeutic agents will be discussed. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  12. Therapeutic Vaccines and Antibodies for Treatment of Orthopoxvirus Infections.

    Science.gov (United States)

    Xiao, Yuhong; Isaacs, Stuart N

    2010-10-01

    Despite the eradication of smallpox several decades ago, variola and monkeypox viruses still have the potential to become significant threats to public health. The current licensed live vaccinia virus-based smallpox vaccine is extremely effective as a prophylactic vaccine to prevent orthopoxvirus infections, but because of safety issues, it is no longer given as a routine vaccine to the general population. In the event of serious human orthopoxvirus infections, it is important to have treatments available for individual patients as well as their close contacts. The smallpox vaccine and vaccinia immune globulin (VIG) were used in the past as therapeutics for patients exposed to smallpox. VIG was also used in patients who were at high risk of developing complications from smallpox vaccination. Thus post-exposure vaccination and VIG treatments may again become important therapeutic modalities. This paper summarizes some of the historic use of the smallpox vaccine and immunoglobulins in the post-exposure setting in humans and reviews in detail the newer animal studies that address the use of therapeutic vaccines and immunoglobulins in orthopoxvirus infections as well as the development of new therapeutic monoclonal antibodies.

  13. Therapeutic Vaccines and Antibodies for Treatment of Orthopoxvirus Infections

    Directory of Open Access Journals (Sweden)

    Stuart N. Isaacs

    2010-10-01

    Full Text Available Despite the eradication of smallpox several decades ago, variola and monkeypox viruses still have the potential to become significant threats to public health. The current licensed live vaccinia virus-based smallpox vaccine is extremely effective as a prophylactic vaccine to prevent orthopoxvirus infections, but because of safety issues, it is no longer given as a routine vaccine to the general population. In the event of serious human orthopoxvirus infections, it is important to have treatments available for individual patients as well as their close contacts. The smallpox vaccine and vaccinia immune globulin (VIG were used in the past as therapeutics for patients exposed to smallpox. VIG was also used in patients who were at high risk of developing complications from smallpox vaccination. Thus post-exposure vaccination and VIG treatments may again become important therapeutic modalities. This paper summarizes some of the historic use of the smallpox vaccine and immunoglobulins in the post-exposure setting in humans and reviews in detail the newer animal studies that address the use of therapeutic vaccines and immunoglobulins in orthopoxvirus infections as well as the development of new therapeutic monoclonal antibodies.

  14. [Development of HPLC analysis methods for therapeutic monoclonal antibodies].

    Science.gov (United States)

    Todoroki, Kenichiro

    2015-01-01

    Therapeutic monoclonal antibody (mAb) preparations are produced from cultured cells; therefore, detailed and multidimensional analyses of their heterogeneities are required. We analyzed five commercially available mAb preparations by high-temperature reversed-phase LC using a wide-pore core-shell column for pluralistic quality assessment. At a highly elevated column temperature, isopropanol with high eluotropic strength coefficients and a wide-pore core-shell type octyl column showed good peak resolution of the investigated mAbs and their related constituents. We used this method to estimate the residual rate of intact mAbs after a heat aggregation treatment and conducted fragmentation analysis by analyzing their pepsin digests. Each peak component was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. All results were compared with those of reversed-phase and size exclusion analyses.

  15. Therapeutic monoclonal antibody N-glycosylation - Structure, function and therapeutic potential.

    Science.gov (United States)

    Cymer, Florian; Beck, Hermann; Rohde, Adelheid; Reusch, Dietmar

    2017-11-24

    Therapeutic antibodies (IgG-type) contain several post-translational modifications (PTMs) whereby introducing a large heterogeneity, both structural and functional, into this class of therapeutics. Of these modifications, glycosylation in the fragment crystallizable (Fc) region is the most heterogeneous PTM, which can affect the stability of the molecule and interactions with Fc-receptors in vivo. Hence, the glycoform distribution can affect the mode of action and have implications for bioactivity, safety and efficacy of the drug. Main topics of the manuscript include: What factors influence the (Fc) glycan pattern in therapeutic antibodies and how can these glycans be characterized? How does structure of the Fc-glycan relate to function and what methods are available to characterize those functions? Although heterogeneous in their scope, the different sections are intended to combine current knowledge on structure-function correlations of IgG glycan structures with regard to Fc (effector) functions, as well as basic aspects and methodologies for their assessment. Copyright © 2017. Published by Elsevier Ltd.

  16. Avian Diagnostic and Therapeutic Antibodies to Viral Emerging Pathogens

    Energy Technology Data Exchange (ETDEWEB)

    David Bradley

    2011-03-31

    During the current period the following key objectives were achieved: demonstration of high titer antibody production by geese following immunization with inactived H1N1 virus; completion of the epitope mapping of West Nile Virus-specific goose antibodies and initiation of epitope mapping of H1N1 flu-specific goose antibodies; advancement in scalable purification of goose antibodies.

  17. The antibody response against human and chimeric anti-TNF therapeutic antibodies primarily targets the TNF binding region

    NARCIS (Netherlands)

    van Schie, K. A.; Hart, M. H.; de Groot, E. R.; Kruithof, S.; Aarden, L. A.; Wolbink, G. J.; Rispens, T.

    2015-01-01

    In a subset of patients, anti tumour necrosis factor (TNF) therapeutic antibodies are immunogenic, resulting in the formation of antidrug antibodies (ADAs). Neutralising ADAs compete with TNF for its binding site and reduces the effective serum concentration, causing clinical non-response. It is

  18. Immunogenicity of therapeutic antibodies : Immunological mechanisms & clinical consequences

    NARCIS (Netherlands)

    van Schie, K.A.J.

    2017-01-01

    Monoclonal antibody therapy has revolutionized the treatment of many diseases, including chronic inflammatory diseases and cancer. Antibody therapy can unfortunately also elicit an unwanted immune response, leading to anti-drug antibodies (ADA). It is well known that ADA can lower the level of free

  19. Enzymatic Inactivation of Endogenous IgG by IdeS Enhances Therapeutic Antibody Efficacy.

    Science.gov (United States)

    Järnum, Sofia; Runström, Anna; Bockermann, Robert; Winstedt, Lena; Crispin, Max; Kjellman, Christian

    2017-09-01

    Endogenous plasma IgG sets an immunologic threshold that dictates the activity of tumor-directed therapeutic antibodies. Saturation of cellular antibody receptors by endogenous antibody limits antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Here, we show how enzymatic cleavage of IgG using the bacterial enzyme IdeS can be utilized to empty both high and low affinity Fcγ-receptors and clear the entire endogenous antibody pool. Using in vitro models, tumor animal models as well as ex vivo analysis of sera collected during a previous clinical trial with IdeS, we show how clearing of competing plasma antibody levels with IdeS unblocks cellular antibody receptors. We show that therapeutic antibodies against breast cancer (trastuzumab), colon cancer (cetuximab), and lymphomas (rituximab and alemtuzumab) can be potentiated when endogenous IgG is removed. Overall, IdeS is shown to be a potent tool to reboot the human antibody repertoire and to generate a window to preferentially load therapeutic antibodies onto effector cells and thereby create an armada of dedicated tumor-seeking immune cells. Mol Cancer Ther; 16(9); 1887-97. ©2017 AACR . ©2017 American Association for Cancer Research.

  20. Intracellular trafficking of new anticancer therapeutics: antibody-drug conjugates.

    Science.gov (United States)

    Kalim, Muhammad; Chen, Jie; Wang, Shenghao; Lin, Caiyao; Ullah, Saif; Liang, Keying; Ding, Qian; Chen, Shuqing; Zhan, Jinbiao

    2017-01-01

    Antibody-drug conjugate (ADC) is a milestone in targeted cancer therapy that comprises of monoclonal antibodies chemically linked to cytotoxic drugs. Internalization of ADC takes place via clathrin-mediated endocytosis, caveolae-mediated endocytosis, and pinocytosis. Conjugation strategies, endocytosis and intracellular trafficking optimization, linkers, and drugs chemistry present a great challenge for researchers to eradicate tumor cells successfully. This inventiveness of endocytosis and intracellular trafficking has given considerable momentum recently to develop specific antibodies and ADCs to treat cancer cells. It is significantly advantageous to emphasize the endocytosis and intracellular trafficking pathways efficiently and to design potent engineered conjugates and biological entities to boost efficient therapies enormously for cancer treatment. Current studies illustrate endocytosis and intracellular trafficking of ADC, protein, and linker strategies in unloading and also concisely evaluate practically applicable ADCs.

  1. Production of vaccines and therapeutic antibodies for veterinary applications in transgenic plants: an overview.

    Science.gov (United States)

    Floss, Doreen Manuela; Falkenburg, Dieter; Conrad, Udo

    2007-06-01

    During the past two decades, antibodies, antibody derivatives and vaccines have been developed for therapeutic and diagnostic applications in human and veterinary medicine. Numerous species of dicot and monocot plants have been genetically modified to produce antibodies or vaccines, and a number of diverse transformation methods and strategies to enhance the accumulation of the pharmaceutical proteins are now available. Veterinary applications are the specific focus of this article, in particular for pathogenic viruses, bacteria and eukaryotic parasites. We focus on the advantages and remaining challenges of plant-based therapeutic proteins for veterinary applications with emphasis on expression platforms, technologies and economic considerations.

  2. Glycosylation engineering of therapeutic IgG antibodies: challenges for the safety, functionality and efficacy.

    Science.gov (United States)

    Mimura, Yusuke; Katoh, Toshihiko; Saldova, Radka; O'Flaherty, Roisin; Izumi, Tomonori; Mimura-Kimura, Yuka; Utsunomiya, Toshiaki; Mizukami, Yoichi; Yamamoto, Kenji; Matsumoto, Tsuneo; Rudd, Pauline M

    2017-06-08

    Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex-type oligosaccharide attached to Asn297 of the Fc is essential for antibody effector functions, fucose and outer-arm sugars attached to the core heptasaccharide that generate structural heterogeneity (glycoforms) exhibit unique biological activities. Hence, efficient and quantitative glycan analysis techniques have been increasingly important for the development and quality control of therapeutic antibodies, and glycan profiles of the Fc are recognized as critical quality attributes. In the past decade our understanding of the influence of glycosylation on the structure/function of IgG-Fc has grown rapidly through X-ray crystallographic and nuclear magnetic resonance studies, which provides possibilities for the design of novel antibody therapeutics. Furthermore, the chemoenzymatic glycoengineering approach using endoglycosidase-based glycosynthases may facilitate the development of homogeneous IgG glycoforms with desirable functionality as next-generation therapeutic antibodies. Thus, the Fc glycans are fertile ground for the improvement of the safety, functionality, and efficacy of therapeutic IgG antibodies in the era of precision medicine.

  3. IBC's 23rd Antibody Engineering and 10th Antibody Therapeutics Conferences and the Annual Meeting of The Antibody Society: December 2-6, 2012, San Diego, CA.

    Science.gov (United States)

    Marquardt, John; Begent, Richard H J; Chester, Kerry; Huston, James S; Bradbury, Andrew; Scott, Jamie K; Thorpe, Philip E; Veldman, Trudi; Reichert, Janice M; Weiner, Louis M

    2012-01-01

    Now in its 23rd and 10th years, respectively, the Antibody Engineering and Antibody Therapeutics conferences are the Annual Meeting of The Antibody Society. The scientific program covers the full spectrum of challenges in antibody research and development from basic science through clinical development. In this preview of the conferences, the chairs provide their thoughts on sessions that will allow participants to track emerging trends in (1) the development of next-generation immunomodulatory antibodies; (2) the complexity of the environment in which antibodies must function; (3) antibody-targeted central nervous system (CNS) therapies that cross the blood brain barrier; (4) the extension of antibody half-life for improved efficacy and pharmacokinetics (PK)/pharmacodynamics (PD); and (5) the application of next generation DNA sequencing to accelerate antibody research. A pre-conference workshop on Sunday, December 2, 2012 will update participants on recent intellectual property (IP) law changes that affect antibody research, including biosimilar legislation, the America Invents Act and recent court cases. Keynote presentations will be given by Andreas Plückthun (University of Zürich), who will speak on engineering receptor ligands with powerful cellular responses; Gregory Friberg (Amgen Inc.), who will provide clinical updates of bispecific antibodies; James D. Marks (University of California, San Francisco), who will discuss a systems approach to generating tumor targeting antibodies; Dario Neri (Swiss Federal Institute of Technology Zürich), who will speak about delivering immune modulators at the sites of disease; William M. Pardridge (University of California, Los Angeles), who will discuss delivery across the blood-brain barrier; and Peter Senter (Seattle Genetics, Inc.), who will present his vision for the future of antibody-drug conjugates. For more information on these meetings or to register to attend, please visit www.IBCLifeSciences.com/Antibody

  4. A novel highly potent therapeutic antibody neutralizes multiple human chemokines and mimics viral immune modulation.

    Science.gov (United States)

    Scalley-Kim, Michelle L; Hess, Bruce W; Kelly, Ryan L; Krostag, Anne-Rachel F; Lustig, Kurt H; Marken, John S; Ovendale, Pamela J; Posey, Aaron R; Smolak, Pamela J; Taylor, Janelle D L; Wood, C L; Bienvenue, David L; Probst, Peter; Salmon, Ruth A; Allison, Daniel S; Foy, Teresa M; Raport, Carol J

    2012-01-01

    Chemokines play a key role in leukocyte recruitment during inflammation and are implicated in the pathogenesis of a number of autoimmune diseases. As such, inhibiting chemokine signaling has been of keen interest for the development of therapeutic agents. This endeavor, however, has been hampered due to complexities in the chemokine system. Many chemokines have been shown to signal through multiple receptors and, conversely, most chemokine receptors bind to more than one chemokine. One approach to overcoming this complexity is to develop a single therapeutic agent that binds and inactivates multiple chemokines, similar to an immune evasion strategy utilized by a number of viruses. Here, we describe the development and characterization of a novel therapeutic antibody that targets a subset of human CC chemokines, specifically CCL3, CCL4, and CCL5, involved in chronic inflammatory diseases. Using a sequential immunization approach, followed by humanization and phage display affinity maturation, a therapeutic antibody was developed that displays high binding affinity towards the three targeted chemokines. In vitro, this antibody potently inhibits chemotaxis and chemokine-mediated signaling through CCR1 and CCR5, primary chemokine receptors for the targeted chemokines. Furthermore, we have demonstrated in vivo efficacy of the antibody in a SCID-hu mouse model of skin leukocyte migration, thus confirming its potential as a novel therapeutic chemokine antagonist. We anticipate that this antibody will have broad therapeutic utility in the treatment of a number of autoimmune diseases due to its ability to simultaneously neutralize multiple chemokines implicated in disease pathogenesis.

  5. Antibody-based therapeutics against components of the IGF system

    OpenAIRE

    Feng, Yang; Dimitrov, Dimiter S.

    2012-01-01

    The insulin-like growth factor I (IGF-I) receptor (IGF-1R) is overexpressed in most human neoplasms tested so far. Many tumors in young patients produce high levels of the IGF-1R ligands, IGF-I and IGF-II. Given the complexity of the IGF signaling pathway, its complete inhibition may require combination therapies with antibodies targeting both IGF-1R and IGF-II.

  6. MONOCLONAL ANTIBODIES AND BREAST CANCER. CURRENT THERAPEUTIC PROGRESS

    OpenAIRE

    Collignon, Joëlle; Gennigens, Christine; Rorive, Andrée; Coucke, Philippe; Lifrange, Eric; Maweja, Sylvie; Fillet, Georges; Jerusalem, Guy

    2009-01-01

    About 9,500 new breast cancers are diagnosed in Belgium every year. Improvement of our knowledge of altered molecular events leading to the proliferation of tumor cells has resulted in the development of targeted therapies in subgroups of cancers. One of the first validation of targeted therapy is the anti-HER-2 monoclonal antibody trastuzumab (Herceptin) in patients with overexpression of human epidermal growth factor receptor type 2 (HER2) occurring in 20 to 25% of invasive breast carcinoma...

  7. Therapeutic monoclonal antibodies and derivatives: Historical perspectives and future directions.

    Science.gov (United States)

    Rodgers, Kyla R; Chou, Richard C

    2016-11-01

    Biologics, both monoclonal antibodies (mAbs) and fusion proteins, have revolutionized the practice of medicine. This year marks the 30th anniversary of the Food and Drug Administration approval of the first mAb for human use. In this review, we examine the biotechnological breakthroughs that spurred the explosive development of the biopharmaceutical mAb industry, as well as how critical lessons learned about human immunology informed the development of improved biologics. We also discuss the most common mechanisms of action of currently approved biologics and the indications for which they have been approved to date. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Monoclonal Antibody Shows Promise as Potential Therapeutic for MERS | Poster

    Science.gov (United States)

    A monoclonal antibody has proven effective in preventing Middle Eastern Respiratory Syndrome (MERS) in lab animals, suggesting further development as a potential intervention for the deadly disease in humans, according to new research. MERS is a newly emerged coronavirus first detected in humans in 2012. Most cases have occurred in the Middle East, but the disease has appeared elsewhere. In all, MERS has infected more than 1,700 individuals and killed more than 600, according to the World Health Organization. No vaccines or antiviral therapies currently exist. Several candidate vaccines are being developed, and some have been tested in animal models, a prerequisite to human clinical trials.

  9. Novel drug and soluble target tolerant antidrug antibody assay for therapeutic antibodies bearing the P329G mutation.

    Science.gov (United States)

    Wessels, Uwe; Schick, Eginhard; Ritter, Mirko; Kowalewsky, Frank; Heinrich, Julia; Stubenrauch, Kay

    2017-06-01

    Bridging immunoassays for detection of antidrug antibodies (ADAs) are typically susceptible to high concentrations of residual drug. Sensitive drug-tolerant assays are, therefore, needed. An immune complex assay to detect ADAs against therapeutic antibodies bearing Pro329Gly mutation was established. The assay uses antibodies specific for the Pro329Gly mutation for capture and human soluble Fcγ receptor for detection. When compared with a bridging assay, the new assay showed similar precision, high sensitivity to IgG1 ADA and dramatically improved drug tolerance. However, it was not able to detect early (IgM-based) immune responses. Applied in combination with a bridging assay, the novel assay serves as orthogonal assay for immunogenicity assessment and allows further characterization of ADA responses.

  10. Biosensing Probe for Quality Control Monitoring of the Structural Integrity of Therapeutic Antibodies.

    Science.gov (United States)

    Watanabe, Hideki; Yageta, Seiki; Imamura, Hiroshi; Honda, Shinya

    2016-10-18

    Ideal quality control of therapeutic antibodies involves analytical techniques with high-sensitivity, high-resolution, and high-throughput performance. Few technologies that assess the physicochemical heterogeneity of antibodies, however, meet all the required demands. We developed a biosensing method for the quality control of therapeutic antibodies based on an artificial protein, AF.2A1, which discriminates between the native and the non-native three-dimensional structures of immunoglobulin G (IgG). AF.2A1 specifically recognized non-native IgG spiked into a solution of native IgG, thereby making it possible to detect contamination by a small amount of non-native IgG, which is difficult using conventional size-based separation or spectroscopic techniques. Using AF.2A1 as an analytical probe, we determined the concentration of non-native IgG formed under various pH conditions. The probe was also applicable to accelerated tests of the long-term stability of a therapeutic antibody, allowing monitoring of the formation of non-native IgG at elevated temperatures and extended periods of storage. AF.2A1, a proteinous probe, can be combined with established methods or devices to achieve high-throughput assays and provides the potential for probe-based biosensing for the quality control of therapeutic antibodies.

  11. Lyophilized Silk Fibroin Hydrogels for the Sustained Local Delivery of Therapeutic Monoclonal Antibodies

    Science.gov (United States)

    Guziewicz, Nicholas; Best, Annie; Perez-Ramirez, Bernardo; Kaplan, David L.

    2011-01-01

    The development of sustained delivery systems compatible with protein therapeutics continues to be a significant unmet need. A lyophilized silk fibroin hydrogel matrix (lyogel) for the sustained release of pharmaceutically relevant monoclonal antibodies is described. Sonication of silk fibroin prior to antibody incorporation avoids exposing the antibody to the sol-gel transition inducing shear stress. Fourier Transform Infrared (FTIR) analysis showed no change in silk structural composition between hydrogel and lyogel or with increasing silk fibroin concentration. Antibody release from hydrogels occurred rapidly over 10 days regardless of silk concentration. Upon lyophilization, sustained antibody release was observed over 38 days from lyogels containing 6.2% (w/w) silk fibroin and above. In 3.2% (w/w) silk lyogels, antibody release was comparable to hydrogels. Swelling properties of lyogels followed a similar threshold behavior. Lyogels at 3.2% (w/w) silk recovered approximately 90% of their fluid mass upon rehydration, while approximately 50% fluid recovery was observed at 6.2% (w/w) silk and above. Antibody release was primarily governed by hydrophobic/hydrophilic silk-antibody interactions and secondarily altered by the hydration resistance of the lyogel. Hydration resistance was controlled by altering β-sheet (crystalline) density of the matrix. The antibody released from lyogels maintained biological activity. Silk lyogels offer an advantage as a delivery matrix over other hydrogel materials for the slow release of the loaded protein, making lyogels suitable for long-term sustained release applications. PMID:21216004

  12. Plant expression systems for early stage discovery and development of lead therapeutic antibodies.

    Science.gov (United States)

    Virdi, Vikram; Juarez, Paloma; Depicker, Ann

    2015-12-23

    Antibodies for human clinical applications are predominantly produced in mammalian expression systems, with Chinese hamster ovary (CHO) cells being the gold standard. CHO cells are ideal for the manufacturing of the IgG class of antibodies, but not for the production of complex antibodies like secretory IgAs (SIgAs) and IgMs, which remain unavailable for clinical use. In contrast, plant seeds and leaves hold the promise to produce SIgAs, IgMs and similar complex antibody formats to scalable amounts. Using transient transformation of Nicotiana benthamiana leaves, complex antibody formats can be produced up to milligram amounts in less than a month. Based on these merits, we propose a model for early-phase exploration and designing of innovative antibody formats for therapeutic application. Further in this essay, we elaborate how the model was followed during the selection of novel antibodies for seed-based production. This exploratory model led to the engineering of novel light-chain devoid porcinized-llama antibodies (VHH-Fc) of the IgG (VHH-IgG) and IgA (VHH-IgA) isotypes and also tetravalent dimeric and SIgAs. The proposed strategy may lead to plant-based rapid engineering of innovative antibodies more apt and efficacious for therapy, and in the coarse also add to the understanding of their mode of action.

  13. Nanobodies and Nanobody-Based Human Heavy Chain Antibodies As Antitumor Therapeutics

    Directory of Open Access Journals (Sweden)

    Peter Bannas

    2017-11-01

    -based human heavy chain antibodies as antitumor therapeutics.

  14. Transgenic mouse strains as platforms for the successful discovery and development of human therapeutic monoclonal antibodies.

    Science.gov (United States)

    Green, Larry L

    2014-03-01

    Transgenic mice have yielded seven of the ten currently-approved human antibody drugs, making them the most successful platform for the discovery of fully human antibody therapeutics. The use of the in vivo immune system helps drive this success by taking advantage of the natural selection process that produces antibodies with desirable characteristics. Appropriately genetically-engineered mice act as robust engines for the generation of diverse repertoires of affinity- matured fully human variable regions with intrinsic properties necessary for successful antibody drug development including high potency, specificity, manufacturability, solubility and low risk of immunogenicity. A broad range of mAb drug targets are addressable in these mice, comprising both secreted and transmembrane targets, including membrane multi-spanning targets, as well as human target antigens that share high sequence identity with their mouse orthologue. Transgenic mice can routinely yield antibodies with sub-nanomolar binding affinity for their antigen, with lead candidate mAbs frequently possessing affinities for binding to their target of less than 100 picomolar, without requiring any ex vivo affinity optimization. While the originator transgenic mice platforms are no longer broadly available, a new generation of transgenic platforms is in development for discovery of the next wave of human therapeutic antibodies.

  15. Structural basis for EGF receptor inhibition by the therapeutic antibody IMC-11F8.

    Science.gov (United States)

    Li, Shiqing; Kussie, Paul; Ferguson, Kathryn M

    2008-02-01

    Therapeutic anticancer strategies that target and inactivate the epidermal growth factor receptor (EGFR) are under intense study in the clinic. Here we describe the mechanism of EGFR inhibition by an antibody drug IMC-11F8. IMC-11F8 is a fully human antibody that has similar antitumor potency as the chimeric cetuximab/Erbitux and might represent a safer therapeutic alternative. We report the X-ray crystal structure of the Fab fragment of IMC-11F8 (Fab11F8) in complex with the entire extracellular region and with isolated domain III of EGFR. We compare this to our previous study of the cetuximab/EGFR interaction. Fab11F8 interacts with a remarkably similar epitope, but through a completely different set of interactions. Both the similarities and differences in binding of these two antibodies have important implications for the development of inhibitors that could exploit this same mechanism of EGFR inhibition.

  16. Fast and scalable purification of a therapeutic full-length antibody based on process crystallization.

    Science.gov (United States)

    Smejkal, Benjamin; Agrawal, Neeraj J; Helk, Bernhard; Schulz, Henk; Giffard, Marion; Mechelke, Matthias; Ortner, Franziska; Heckmeier, Philipp; Trout, Bernhardt L; Hekmat, Dariusch

    2013-09-01

    The potential of process crystallization for purification of a therapeutic monoclonal IgG1 antibody was studied. The purified antibody was crystallized in non-agitated micro-batch experiments for the first time. A direct crystallization from clarified CHO cell culture harvest was inhibited by high salt concentrations. The salt concentration of the harvest was reduced by a simple pretreatment step. The crystallization process from pretreated harvest was successfully transferred to stirred tanks and scaled-up from the mL-scale to the 1 L-scale for the first time. The crystallization yield after 24 h was 88-90%. A high purity of 98.5% was reached after a single recrystallization step. A 17-fold host cell protein reduction was achieved and DNA content was reduced below the detection limit. High biological activity of the therapeutic antibody was maintained during the crystallization, dissolving, and recrystallization steps. Crystallization was also performed with impure solutions from intermediate steps of a standard monoclonal antibody purification process. It was shown that process crystallization has a strong potential to replace Protein A chromatography. Fast dissolution of the crystals was possible. Furthermore, it was shown that crystallization can be used as a concentrating step and can replace several ultra-/diafiltration steps. Molecular modeling suggested that a negative electrostatic region with interspersed exposed hydrophobic residues on the Fv domain of this antibody is responsible for the high crystallization propensity. As a result, process crystallization, following the identification of highly crystallizable antibodies using molecular modeling tools, can be recognized as an efficient, scalable, fast, and inexpensive alternative to key steps of a standard purification process for therapeutic antibodies. Copyright © 2013 Wiley Periodicals, Inc.

  17. The safety of therapeutic monoclonal antibodies: implications for cancer therapy including immuno-checkpoint inhibitors.

    Science.gov (United States)

    Demlova, R; Valík, D; Obermannova, R; ZdraŽilová-Dubská, L

    2016-12-21

    Monoclonal antibody-based treatment of cancer has been established as one of the most successful therapeutic strategies for both hematologic malignancies and solid tumors. In addition to targeting cancer antigens antibodies can also modulate immunological pathways that are critical to immune surveillance. Antibody therapy directed against several negative immunologic regulators (checkpoints) is demonstrating significant success in the past few years. Immune checkpoint inhibitors, ipilimumab, pembrolizumab and nivolumab, have shown significant clinical benefit in several malignancies and are already approved for advanced melanoma and squamous NSCLC. Based on their mechanism of action, these agents can exert toxicities that are unlike conventional cytotoxic chemotherapy, whose nature is close to autoimmune diseases - immune related adverse events (irAEs). In this review we focus on the spectrum of irAEs associated with immune checkpoint antibodies, discussing the pharmacological treatment strategy and possible clinical impact.

  18. Neural stem cells as a novel platform for tumor-specific delivery of therapeutic antibodies.

    Directory of Open Access Journals (Sweden)

    Richard T Frank

    Full Text Available BACKGROUND: Recombinant monoclonal antibodies have emerged as important tools for cancer therapy. Despite the promise shown by antibody-based therapies, the large molecular size of antibodies limits their ability to efficiently penetrate solid tumors and precludes efficient crossing of the blood-brain-barrier into the central nervous system (CNS. Consequently, poorly vascularized solid tumors and CNS metastases cannot be effectively treated by intravenously-injected antibodies. The inherent tumor-tropic properties of human neural stem cells (NSCs can potentially be harnessed to overcome these obstacles and significantly improve cancer immunotherapy. Intravenously-delivered NSCs preferentially migrate to primary and metastatic tumor sites within and outside the CNS. Therefore, we hypothesized that NSCs could serve as an ideal cellular delivery platform for targeting antibodies to malignant tumors. METHODS AND FINDINGS: As proof-of-concept, we selected Herceptin (trastuzumab, a monoclonal antibody widely used to treat HER2-overexpressing breast cancer. HER2 overexpression in breast cancer is highly correlated with CNS metastases, which are inaccessible to trastuzumab therapy. Therefore, NSC-mediated delivery of trastuzumab may improve its therapeutic efficacy. Here we report, for the first time, that human NSCs can be genetically modified to secrete anti-HER2 immunoglobulin molecules. These NSC-secreted antibodies assemble properly, possess tumor cell-binding affinity and specificity, and can effectively inhibit the proliferation of HER2-overexpressing breast cancer cells in vitro. We also demonstrate that immunoglobulin-secreting NSCs exhibit preferential tropism to tumor cells in vivo, and can deliver antibodies to human breast cancer xenografts in mice. CONCLUSIONS: Taken together, these results suggest that NSCs modified to secrete HER2-targeting antibodies constitute a promising novel platform for targeted cancer immunotherapy. Specifically

  19. Impact of Depleting Therapeutic Monoclonal Antibodies on the Host Adaptive Immunity: A Bonus or a Malus?

    Science.gov (United States)

    Deligne, Claire; Milcent, Benoît; Josseaume, Nathalie; Teillaud, Jean-Luc; Sibéril, Sophie

    2017-01-01

    Clinical responses to anti-tumor monoclonal antibody (mAb) treatment have been regarded for many years only as a consequence of the ability of mAbs to destroy tumor cells by innate immune effector mechanisms. More recently, it has also been shown that anti-tumor antibodies can induce a long-lasting anti-tumor adaptive immunity, likely responsible for durable clinical responses, a phenomenon that has been termed the vaccinal effect of antibodies. However, some of these anti-tumor antibodies are directed against molecules expressed both by tumor cells and normal immune cells, in particular lymphocytes, and, hence, can also strongly affect the host adaptive immunity. In addition to a delayed recovery of target cells, lymphocyte depleting-mAb treatments can have dramatic consequences on the adaptive immune cell network, its rebound, and its functional capacities. Thus, in this review, we will not only discuss the mAb-induced vaccinal effect that has emerged from experimental preclinical studies and clinical trials but also the multifaceted impact of lymphocytes-depleting therapeutic antibodies on the host adaptive immunity. We will also discuss some of the molecular and cellular mechanisms of action whereby therapeutic mAbs induce a long-term protective anti-tumor effect and the relationship between the mAb-induced vaccinal effect and the immune response against self-antigens.

  20. Impact of Depleting Therapeutic Monoclonal Antibodies on the Host Adaptive Immunity: A Bonus or a Malus?

    Directory of Open Access Journals (Sweden)

    Claire Deligne

    2017-08-01

    Full Text Available Clinical responses to anti-tumor monoclonal antibody (mAb treatment have been regarded for many years only as a consequence of the ability of mAbs to destroy tumor cells by innate immune effector mechanisms. More recently, it has also been shown that anti-tumor antibodies can induce a long-lasting anti-tumor adaptive immunity, likely responsible for durable clinical responses, a phenomenon that has been termed the vaccinal effect of antibodies. However, some of these anti-tumor antibodies are directed against molecules expressed both by tumor cells and normal immune cells, in particular lymphocytes, and, hence, can also strongly affect the host adaptive immunity. In addition to a delayed recovery of target cells, lymphocyte depleting-mAb treatments can have dramatic consequences on the adaptive immune cell network, its rebound, and its functional capacities. Thus, in this review, we will not only discuss the mAb-induced vaccinal effect that has emerged from experimental preclinical studies and clinical trials but also the multifaceted impact of lymphocytes-depleting therapeutic antibodies on the host adaptive immunity. We will also discuss some of the molecular and cellular mechanisms of action whereby therapeutic mAbs induce a long-term protective anti-tumor effect and the relationship between the mAb-induced vaccinal effect and the immune response against self-antigens.

  1. Complement in therapy and disease: Regulating the complement system with antibody-based therapeutics.

    Science.gov (United States)

    Melis, Joost P M; Strumane, Kristin; Ruuls, Sigrid R; Beurskens, Frank J; Schuurman, Janine; Parren, Paul W H I

    2015-10-01

    Complement is recognized as a key player in a wide range of normal as well as disease-related immune, developmental and homeostatic processes. Knowledge of complement components, structures, interactions, and cross-talk with other biological systems continues to grow and this leads to novel treatments for cancer, infectious, autoimmune- or age-related diseases as well as for preventing transplantation rejection. Antibodies are superbly suited to be developed into therapeutics with appropriate complement stimulatory or inhibitory activity. Here we review the design, development and future of antibody-based drugs that enhance or dampen the complement system. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Prion protein-specific antibodies-development, modes of action and therapeutics application.

    Science.gov (United States)

    Rovis, Tihana Lenac; Legname, Giuseppe

    2014-10-01

    Prion diseases or Transmissible Spongiform Encephalopathies (TSEs) are lethal neurodegenerative disorders involving the misfolding of the host encoded cellular prion protein, PrPC. This physiological form of the protein is expressed throughout the body, and it reaches the highest levels in the central nervous system where the pathology occurs. The conversion into the pathogenic isoform denoted as prion or PrPSc is the key event in prion disorders. Prominent candidates for the treatment of prion diseases are antibodies and their derivatives. Anti-PrPC antibodies are able to clear PrPSc from cell culture of infected cells. Furthermore, application of anti-PrPC antibodies suppresses prion replication in experimental animal models. Major drawbacks of immunotherapy are immune tolerance, the risks of neurotoxic side effects, limited ability of compounds to cross the blood-brain barrier and their unfavorable pharmacokinetic. The focus of this review is to recapitulate the current understanding of the molecular mechanisms for antibody mediated anti-prion activity. Although relevant for designing immunotherapeutic tools, the characterization of key antibody parameters shaping the molecular mechanism of the PrPC to PrPSc conversion remains elusive. Moreover, this review illustrates the various attempts towards the development of anti-PrP antibody compounds and discusses therapeutic candidates that modulate PrP expression.

  3. Anti-PD-1 Antibodies as a Therapeutic Strategy in Classical Hodgkin Lymphoma.

    Science.gov (United States)

    Jain, Michael D; Kuruvilla, John

    2017-08-17

    Classical Hodgkin lymphoma (cHL) is defined by malignant Reed-Sternberg (RS) cells that recruit non-malignant immune cells into a supportive tumour microenvironment. In cHL, this is driven, in part, by genomic alterations of the 9p24.1 locus encoding the immune checkpoint ligands PD-L1 and PD-L2. Therapeutic anti-PD-1 antibodies have been developed that competitively inhibit the interaction between PD-1 and its ligands. Clinical trials of anti-PD-1 antibodies in cHL demonstrate high overall response rates but relapses still occur and new clinical challenges exist for toxicity management and response assessment. This review discusses the biological and clinical features of anti-PD-1 antibody therapy in cHL.

  4. In silico selection of therapeutic antibodies for development: Viscosity, clearance, and chemical stability

    Science.gov (United States)

    Sharma, Vikas K.; Patapoff, Thomas W.; Kabakoff, Bruce; Pai, Satyan; Hilario, Eric; Zhang, Boyan; Li, Charlene; Borisov, Oleg; Kelley, Robert F.; Chorny, Ilya; Zhou, Joe Z.; Dill, Ken A.; Swartz, Trevor E.

    2014-01-01

    For mAbs to be viable therapeutics, they must be formulated to have low viscosity, be chemically stable, and have normal in vivo clearance rates. We explored these properties by observing correlations of up to 60 different antibodies of the IgG1 isotype. Unexpectedly, we observe significant correlations with simple physical properties obtainable from antibody sequences and by molecular dynamics simulations of individual antibody molecules. mAbs viscosities increase strongly with hydrophobicity and charge dipole distribution and decrease with net charge. Fast clearance correlates with high hydrophobicities of certain complementarity determining regions and with high positive or high negative net charge. Chemical degradation from tryptophan oxidation correlates with the average solvent exposure time of tryptophan residues. Aspartic acid isomerization rates can be predicted from solvent exposure and flexibility as determined by molecular dynamics simulations. These studies should aid in more rapid screening and selection of mAb candidates during early discovery. PMID:25512516

  5. Specific decrease in solution viscosity of antibodies by arginine for therapeutic formulations.

    Science.gov (United States)

    Inoue, Naoto; Takai, Eisuke; Arakawa, Tsutomu; Shiraki, Kentaro

    2014-06-02

    Unacceptably high viscosity is observed in high protein concentration formulations due to extremely large therapeutic dose of antibodies and volume restriction of subcutaneous route of administration. Here, we show that a protein aggregation suppressor, arginine hydrochloride (ArgHCl), specifically decreases viscosity of antibody formulations. The viscosities of bovine gamma globulin (BGG) solution at 250 mg/mL and human gamma globulin (HGG) solution at 292 mg/mL at a physiological pH were too high for subcutaneous injections, but decreased to an acceptable level (below 50 cP) in the presence of 1,000 mM ArgHCl. ArgHCl also decreased the viscosity of BGG solution at acidic and alkaline pHs. Interestingly, ArgHCl decreased the viscosity of antibody solutions (BGG, HGG, and human immunoglobulin G) but not globular protein solutions (α-amylase and α-chymotrypsin). These results indicate not only high potency of ArgHCl as an excipient to decrease the solution viscosity of high concentration antibodies formulations but also specific interactions between ArgHCl and antibodies.

  6. Prophylactic and therapeutic activity of fully human monoclonal antibodies directed against Influenza A M2 protein

    Directory of Open Access Journals (Sweden)

    Gwerder Myriam

    2009-12-01

    Full Text Available Abstract Influenza virus infection is a prevalent disease in humans. Antibodies against hemagglutinin have been shown to prevent infection and hence hemagglutinin is the major constituent of current vaccines. Antibodies directed against the highly conserved extracellular domain of M2 have also been shown to mediate protection against Influenza A infection in various animal models. Active vaccination is generally considered the best approach to combat viral diseases. However, passive immunization is an attractive alternative, particularly in acutely exposed or immune compromized individuals, young children and the elderly. We recently described a novel method for the rapid isolation of natural human antibodies by mammalian cell display. Here we used this approach to isolate human monoclonal antibodies directed against the highly conserved extracellular domain of the Influenza A M2 protein. The identified antibodies bound M2 peptide with high affinities, recognized native cell-surface expressed M2 and protected mice from a lethal influenza virus challenge. Moreover, therapeutic treatment up to 2 days after infection was effective, suggesting that M2-specific monoclonals have a great potential as immunotherapeutic agents against Influenza infection.

  7. Laser-induced breakdown detection of temperature-ramp generated aggregates of therapeutic monoclonal antibody.

    Science.gov (United States)

    Menzen, Tim; Friess, Wolfgang; Niessner, Reinhard; Haisch, Christoph

    2015-08-01

    The detection and characterization of protein aggregation is essential during development and quality control of therapeutic proteins, as aggregates are typically inactive and may trigger anti-drug-antibody formation in patients. Especially large multi-domain molecules, such as the important class of therapeutic monoclonal antibodies (mAbs), can form various aggregates that differ in size and morphology. Although particle analysis advanced over the recent years, new techniques and orthogonal methods are highly valued. To our knowledge, the physical principle of laser-induced breakdown detection (LIBD) was not yet applied to sense aggregates in therapeutic protein formulations. We established a LIBD setup to monitor the temperature-induced aggregation of a mAb. The obtained temperature of aggregation was in good agreement with the results from previously published temperature-ramped turbidity and dynamic light scattering measurements. This study demonstrates the promising applicability of LIBD to investigate aggregates from therapeutic proteins. The technique is also adaptive to online detection and size determination, and offers interesting opportunities for morphologic characterization of protein particles and impurities, which will be part of future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Single cycle structure-based humanization of an anti-nerve growth factor therapeutic antibody.

    Science.gov (United States)

    Covaceuszach, Sonia; Marinelli, Sara; Krastanova, Ivet; Ugolini, Gabriele; Pavone, Flaminia; Lamba, Doriano; Cattaneo, Antonino

    2012-01-01

    Most forms of chronic pain are inadequately treated by present therapeutic options. Compelling evidence has accumulated, demonstrating that Nerve Growth Factor (NGF) is a key modulator of inflammatory and nociceptive responses, and is a promising target for the treatment of human pathologies linked to chronic and inflammatory pain. There is therefore a growing interest in the development of therapeutic molecules antagonising the NGF pathway and its nociceptor sensitization actions, among which function-blocking anti-NGF antibodies are particularly relevant candidates.In this respect, the rat anti-NGF αD11 monoclonal antibody (mAb) is a potent antagonist, able to effectively antagonize rodent and human NGF in a variety of in vitro and in vivo systems. Here we show that mAb αD11 displays a significant analgesic effect in two different models of persistent pain in mice, with a remarkable long-lasting activity. In order to advance αD11 mAb towards its clinical application in man, anti-NGF αD11 mAb was humanized by applying a novel single cycle strategy based on the a priori experimental determination of the crystal and molecular structure of the parental Fragment antigen-binding (Fab). The humanized antibody (hum-αD11) was tested in vitro and in vivo, showing that the binding mode and the NGF neutralizing biological activities of the parental antibody are fully preserved, with even a significant affinity improvement. The results firmly establish hum-αD11 as a lead candidate for clinical applications in a therapeutic area with a severe unmet medical need. More generally, the single-cycle structure-based humanization method represents a considerable improvement over the standard humanization methods, which are intrinsically empirical and require several refinement cycles.

  9. Single Cycle Structure-Based Humanization of an Anti-Nerve Growth Factor Therapeutic Antibody

    Science.gov (United States)

    Covaceuszach, Sonia; Marinelli, Sara; Krastanova, Ivet; Ugolini, Gabriele; Pavone, Flaminia; Lamba, Doriano; Cattaneo, Antonino

    2012-01-01

    Most forms of chronic pain are inadequately treated by present therapeutic options. Compelling evidence has accumulated, demonstrating that Nerve Growth Factor (NGF) is a key modulator of inflammatory and nociceptive responses, and is a promising target for the treatment of human pathologies linked to chronic and inflammatory pain. There is therefore a growing interest in the development of therapeutic molecules antagonising the NGF pathway and its nociceptor sensitization actions, among which function-blocking anti-NGF antibodies are particularly relevant candidates. In this respect, the rat anti-NGF αD11 monoclonal antibody (mAb) is a potent antagonist, able to effectively antagonize rodent and human NGF in a variety of in vitro and in vivo systems. Here we show that mAb αD11 displays a significant analgesic effect in two different models of persistent pain in mice, with a remarkable long-lasting activity. In order to advance αD11 mAb towards its clinical application in man, anti-NGF αD11 mAb was humanized by applying a novel single cycle strategy based on the a priori experimental determination of the crystal and molecular structure of the parental Fragment antigen-binding (Fab). The humanized antibody (hum-αD11) was tested in vitro and in vivo, showing that the binding mode and the NGF neutralizing biological activities of the parental antibody are fully preserved, with even a significant affinity improvement. The results firmly establish hum-αD11 as a lead candidate for clinical applications in a therapeutic area with a severe unmet medical need. More generally, the single-cycle structure-based humanization method represents a considerable improvement over the standard humanization methods, which are intrinsically empirical and require several refinement cycles. PMID:22403636

  10. Mammalian cell display technology coupling with AID induced SHM in vitro: an ideal approach to the production of therapeutic antibodies.

    Science.gov (United States)

    Qin, Chang-Fei; Li, Guan-Cheng

    2014-12-01

    Traditional antibody production technology within non-mammalian cell expression systems has shown many unsatisfactory properties for the development of therapeutic antibodies. Nevertheless, mammalian cell display technology reaps the benefits of producing full-length all human antibodies. Together with the developed cytidine deaminase induced in vitro somatic hypermutation technology, mammalian cell display technology provides the opportunity to produce high affinity antibodies that might be ideal for therapeutic application. This review was concentrated on the development of the mammalian cell display technology as well as the activation-induced cytidine deaminase induced in vitro somatic hypermutation technology and their applications for the production of therapeutic antibodies. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. The Impact of Therapeutic Antibodies on the Management of Digestive Diseases: History, Current Practice, and Future Directions.

    Science.gov (United States)

    Sofia, M Anthony; Rubin, David T

    2017-04-01

    The development of therapeutic antibodies represents a revolutionary change in medical therapy for digestive diseases. Beginning with the initial studies that confirmed the pathogenicity of cytokines in inflammatory bowel disease, the development and application of therapeutic antibodies brought challenges and insights into their potential and optimal use. Infliximab was the first biological drug approved for use in Crohn's disease and ulcerative colitis. The lessons learned from infliximab include the importance of immunogenicity and the influence of pharmacokinetics on disease response and outcomes. Building on this foundation, other therapeutic antibodies achieved approval for inflammatory bowel disease and many more are in development for several digestive diseases. In this review, we reflect on the history of therapeutic antibodies and discuss current practice and future directions for the field.

  12. Targeted therapies in hematological malignancies using therapeutic monoclonal antibodies against Eph family receptors.

    Science.gov (United States)

    Charmsaz, Sara; Scott, Andrew M; Boyd, Andrew W

    2017-10-01

    The use of monoclonal antibodies (mAbs) and molecules derived from them has achieved considerable attention and success in recent years, establishing this mode of therapy as an important therapeutic strategy in many cancers, in particular hematological tumors. mAbs recognize cell surface antigens expressed on target cells and mediate their function through various mechanisms such as antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity, or immune system modulation. The efficacy of mAb therapy can be improved when they are conjugated to a highly potent payloads, including cytotoxic drugs and radiolabeled isotopes. The Eph family of proteins has received considerable attention in recent years as therapeutic targets for treatment of both solid and hematological cancers. High expression of Eph receptors on cancer cells compared with low expression levels in normal adult tissues makes them an attractive candidate for cancer immunotherapy. In this review, we detail the modes of action of antibody-based therapies with a focus on the Eph family of proteins as potential targets for therapy in hematological malignancies. Copyright © 2017 ISEH – Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  13. Therapeutic Role for TSP-2 Antibody in a Murine Asthma Model.

    Science.gov (United States)

    Li, Kai; Huang, En Ping; Su, Jin; Zhu, Ping; Lin, Jun; Luo, Shen Qiu; Yang, Cui Lan

    2018-01-27

    Specific immunotherapy, including agonists for Toll-like receptor 2 (TLR2), have been shown to protect from allergies and to have a high immunomodulatory capacity. A new antibody, TSP-2, reactive against an epitope of the extracellular domain of TLR2, was identified. The effect of the antibody on dendritic cells was assessed by immunohistochemistry, Western blot, and flow cytometric analysis. The effect of TSP-2 in a murine asthma model induced with ovalbumin (OVA) was assessed. The model is a form of airway hyperresponsiveness (AHR) and was analyzed by whole-body plethysmography, the measurement of Th1/Th2 cytokines in bronchial alveolar lavage fluid (BALF) and serum by ELISA, and the CCK-8 assay for lymphocyte proliferation. The effect of TSP-2 on the maturation of bone marrow-derived dendritic cells (BMDCs) was assessed by flow cytometric analysis. TSP-2 promoted the maturation of dendritic cells and the proliferation of lymphocyte in vitro and in vivo. The effect of TSP-2 on T helper 1 (Th1)/Th2 cytokine secretion was slightly more powerful than that of Pam3CSK4. TSP-2 antibody reduced AHR and OVA-specific IgE levels in allergic asthma. TSP-2 antibody also reduced lung inflammation and decreased leukocyte numbers in an OVA-sensitized and challenged asthma model. TSP-2 antibody increased OVA-stimulated I-A, CD80, CD86, and MHC-II levels on BMDCs. This study identifies a novel therapeutic strategy for AHR, which uses antibodies reactive against TLR2. It also provides theoretical evidence for the control of allergic asthma by targeting TLR2. © 2018 S. Karger AG, Basel.

  14. Engineered Bovine Antibodies in the Development of Novel Therapeutics, Immunomodulators and Vaccines

    Directory of Open Access Journals (Sweden)

    Madhuri Koti

    2014-05-01

    Full Text Available Some bovine antibodies across all classes are unique, such as the CDR3 of the variable heavy-domain (VH CDR3, which is exceptionally long (up to 66 amino acids, unlike most conventional antibodies where the VH CDR3 loops range from 10 to 25 amino acids. The exceptionally long VH CDR3 is encoded by unusually long germline IGHD genes together with insertion of novel “a” nucleotide rich conserved short nucleotide sequence (CSNS specifically at the IGH V-D junction. Such an exceptionally long VH CDR3 confers unique “knob and stalk” structural architecture where the knob, formed by intra-VH CDR3 disulfide bridges, is separated by 20 Å solvent exposed stalk composed of anti-parallel beta strands. The substitution of the knob with cytokines, such as, erythropoietin and granulocyte colony stimulating factor 3 (granulocyte colony stimulating factor, results in expression of functional fusion proteins with enhanced pharmacokinetics. The beta stranded stalk can be substituted with other rigid structures, for example, repeat alpha helices to form coiled-coil that mimics the beta-stranded stalk and, thus, opens opportunities for insertion of this structure in the CDRs of antibodies across species. Given the versatility of such a structural platform in bovine antibody VH CDR3, it provides the opportunity for the development of new generation of diagnostics, therapeutics, vaccines and immunomodulating drugs.

  15. In vivo imaging using fluorescent antibodies to tumor necrosis factor predicts therapeutic response in Crohn's disease.

    Science.gov (United States)

    Atreya, Raja; Neumann, Helmut; Neufert, Clemens; Waldner, Maximilian J; Billmeier, Ulrike; Zopf, Yurdagül; Willma, Marcus; App, Christine; Münster, Tino; Kessler, Hermann; Maas, Stefanie; Gebhardt, Bernd; Heimke-Brinck, Ralph; Reuter, Eva; Dörje, Frank; Rau, Tilman T; Uter, Wolfgang; Wang, Thomas D; Kiesslich, Ralf; Vieth, Michael; Hannappel, Ewald; Neurath, Markus F

    2014-03-01

    As antibodies to tumor necrosis factor (TNF) suppress immune responses in Crohn's disease by binding to membrane-bound TNF (mTNF), we created a fluorescent antibody for molecular mTNF imaging in this disease. Topical antibody administration in 25 patients with Crohn's disease led to detection of intestinal mTNF(+) immune cells during confocal laser endomicroscopy. Patients with high numbers of mTNF(+) cells showed significantly higher short-term response rates (92%) at week 12 upon subsequent anti-TNF therapy as compared to patients with low amounts of mTNF(+) cells (15%). This clinical response in the former patients was sustained over a follow-up period of 1 year and was associated with mucosal healing observed in follow-up endoscopy. These data indicate that molecular imaging with fluorescent antibodies has the potential to predict therapeutic responses to biological treatment and can be used for personalized medicine in Crohn's disease and autoimmune or inflammatory disorders.

  16. Two-stage chromatographic separation of aggregates for monoclonal antibody therapeutics.

    Science.gov (United States)

    Kumar, Vijesh; Rathore, Anurag S

    2014-11-14

    Aggregates of monoclonal antibody (mAb) therapeutics, due to their perceived impact on immunogenicity, are recognized as a critical quality attribute by the regulatory authorities as well as the industry. Hence, removal of aggregates is a key objective of bioprocessing. At present, this is achieved by a combination of two or more orthogonal chromatographic steps with possible modalities of ion exchange, hydrophobic interaction and mixed mode. A two-stage chromatographic purification process consisting of ion-exchange and hydrophobic interaction modes is proposed in this paper for effective and efficient control of aggregates for a mAb therapeutic. The proposed scheme does not require any intermediate processing of the process stream. Further, baseline separation is achieved for monomer and aggregates resulting in robust performance. This was possible because the proposed operational scheme allowed for an addition of selectivities of the two chromatography modes vs. the traditional two column scheme where part of the separation of aggregates achieved by the first column is lost upon pooling. The proposed process scheme yielded improved separation of aggregates (0% vs. 1-2%) at >95% recovery and reduced overall process time (6h vs. 14 h) for a typical application. Further, clearance of host cell proteins was also shown to have improved with the suggested process scheme. Successful implementation of the proposed scheme has been demonstrated for two different monoclonal antibody therapeutic products. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Purification of the therapeutic antibody trastuzumab from genetically modified plants using safflower Protein A-oleosin oilbody technology.

    Science.gov (United States)

    McLean, Michael D; Chen, Rongji; Yu, Deqiang; Mah, Kor-Zheng; Teat, John; Wang, Haifeng; Zaplachinski, Steve; Boothe, Joseph; Hall, J Christopher

    2012-12-01

    Production of therapeutic monoclonal antibodies using genetically modified plants may provide low cost, high scalability and product safety; however, antibody purification from plants presents a challenge due to the large quantities of biomass that need to be processed. Protein A column chromatography is widely used in the pharmaceutical industry for antibody purification, but its application is limited by cost, scalability and column fouling problems when purifying plant-derived antibodies. Protein A-oleosin oilbodies (Protein A-OB), expressed in transgenic safflower seeds, are relatively inexpensive to produce and provide a new approach for the capture of monoclonal antibodies from plants. When Protein A-OB is mixed with crude extracts from plants engineered to express therapeutic antibodies, the Protein A-OB captures the antibody in the oilbody phase while impurities remain in the aqueous phase. This is followed by repeated partitioning of oilbody phase against an aqueous phase via centrifugation to remove impurities before purified antibody is eluted from the oilbodies. We have developed this purification process to recover trastuzumab, an anti-HER2 monoclonal antibody used for therapy against specific breast-cancers that over express HER2 (human epidermal growth factor receptor 2), from transiently infected Nicotiana benthamiana. Protein A-OB overcomes the fouling problem associated with traditional Protein A chromatography, allowing for the development of an inexpensive, scalable and novel high-resolution method for the capture of antibodies based on simple mixing and phase separation.

  18. Monoclonal Antibodies against Zika Virus: Therapeutics and Their Implications for Vaccine Design.

    Science.gov (United States)

    Wang, Qihui; Yan, Jinghua; Gao, George Fu

    2017-10-15

    Zika virus (ZIKV) has caused global concern due to its association with neurological complications in newborns and adults. Although no vaccines or antivirals against ZIKV infection have been approved to date, hundreds of monoclonal antibodies (MAbs) have been developed in a short period. Here, we first present a complete picture of the ZIKV MAbs and then focus on the neutralizing mechanisms and immune hot spots uncovered through structural studies, which provide insight for therapeutics and vaccine design. Copyright © 2017 American Society for Microbiology.

  19. Therapeutic anti-CD3 monoclonal antibodies: from bench to bedside.

    Science.gov (United States)

    Kuhn, Chantal; Weiner, Howard L

    2016-07-01

    The induction of tolerance is a major goal of immunotherapy. Investigations over the last 20 years have shown that anti-CD3 monoclonal antibodies (mAbs) effectively treat autoimmune disease in animal models and have also shown promise in clinical trials. Tolerance induction by anti-CD3 mAbs is related to the induction of Tregs that control pathogenic autoimmune responses. Here, we review preclinical and clinical studies in which intravenous or mucosal administration of anti-CD3 mAbs has been employed and provide an outlook on future developments to enhance the efficacy of this promising therapeutic approach.

  20. Affinity improvement of a therapeutic antibody by structure-based computational design: generation of electrostatic interactions in the transition state stabilizes the antibody-antigen complex.

    Directory of Open Access Journals (Sweden)

    Masato Kiyoshi

    Full Text Available The optimization of antibodies is a desirable goal towards the development of better therapeutic strategies. The antibody 11K2 was previously developed as a therapeutic tool for inflammatory diseases, and displays very high affinity (4.6 pM for its antigen the chemokine MCP-1 (monocyte chemo-attractant protein-1. We have employed a virtual library of mutations of 11K2 to identify antibody variants of potentially higher affinity, and to establish benchmarks in the engineering of a mature therapeutic antibody. The most promising candidates identified in the virtual screening were examined by surface plasmon resonance to validate the computational predictions, and to characterize their binding affinity and key thermodynamic properties in detail. Only mutations in the light-chain of the antibody are effective at enhancing its affinity for the antigen in vitro, suggesting that the interaction surface of the heavy-chain (dominated by the hot-spot residue Phe101 is not amenable to optimization. The single-mutation with the highest affinity is L-N31R (4.6-fold higher affinity than wild-type antibody. Importantly, all the single-mutations showing increase affinity incorporate a charged residue (Arg, Asp, or Glu. The characterization of the relevant thermodynamic parameters clarifies the energetic mechanism. Essentially, the formation of new electrostatic interactions early in the binding reaction coordinate (transition state or earlier benefits the durability of the antibody-antigen complex. The combination of in silico calculations and thermodynamic analysis is an effective strategy to improve the affinity of a matured therapeutic antibody.

  1. The possibility of using magnetic nanoparticles to increase the therapeutic efficiency of Herceptin antibody.

    Science.gov (United States)

    Rasaneh, Samira; Dadras, Maryam-Rahele

    2015-10-01

    Herceptin is an expensive humanized antibody used for the treatment of early-stage breast cancers. This antibody can cause cardiotoxicity in some patients. In this study, we evaluated the possibility of increasing the therapeutic efficacy of Herceptin by combining magnetic nanoparticles and a permanent magnet for more accumulation in the tumor site. Herceptin magnetic nanoparticles (HMNs) were synthesized and some of their characteristics, such as stability, magnetization, particle size by transmission electron microscopy (TEM), and dynamic light scattering (DLS) technique, were measured. The biodistribution study was checked in mice bearing breast tumor with and without a permanent magnet on the position of the tumor. The therapeutic effects of HMNs were considered in this condition. The size distribution of HMNs determined by the DLS technique was 182±7 nm and the average size by TEM was 100±10 nm. The reductions of 81% and 98% in the mean tumor volume for the group that received HMNs with magnetic field were observed at 42 and 45 days after injection, respectively. The good results in mice indicated that Herceptin-loaded iron oxide nanoparticles with external magnetic field have good potential for use in humans as a targeted drug delivery that needs more investigation.

  2. Biomanufacturing of protective antibodies and other therapeutics in edible plant tissues for oral applications.

    Science.gov (United States)

    Juarez, Paloma; Virdi, Vikram; Depicker, Ann; Orzaez, Diego

    2016-09-01

    Although plant expression systems used for production of therapeutic proteins have the advantage of being scalable at a low price, the downstream processing necessary to obtain pure therapeutic molecules is as expensive as for the traditional Chinese hamster ovary (CHO) platforms. However, when edible plant tissues (EPTs) are used, there is no need for exhaustive purification, because they can be delivered orally as partially purified formulations that are safe for consumption. This economic benefit is especially interesting when high doses of recombinant proteins are required throughout the treatment/prophylaxis period, as is the case for antibodies used for oral passive immunization (OPI). The secretory IgA (SIgA) antibodies, which are highly abundant in the digestive tract and mucosal secretions, and thus the first choice for OPI, have only been successfully produced in plant expression systems. Here, we cover most of the up-to-date examples of EPT-produced pharmaceuticals, including two examples of SIgA aimed at oral delivery. We describe the benefits and drawbacks of delivering partially purified formulations and discuss a number of practical considerations and criteria to take into account when using plant expression systems, such as subcellular targeting, protein degradation, glycosylation patterns and downstream strategies, all crucial for improved yield, high quality and low cost of the final product. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  3. Single pass tangential flow filtration to debottleneck downstream processing for therapeutic antibody production.

    Science.gov (United States)

    Dizon-Maspat, Jemelle; Bourret, Justin; D'Agostini, Anna; Li, Feng

    2012-04-01

    As the therapeutic monoclonal antibody (mAb) market continues to grow, optimizing production processes is becoming more critical in improving efficiencies and reducing cost-of-goods in large-scale production. With the recent trends of increasing cell culture titers from upstream process improvements, downstream capacity has become the bottleneck in many existing manufacturing facilities. Single Pass Tangential Flow Filtration (SPTFF) is an emerging technology, which is potentially useful in debottlenecking downstream capacity, especially when the pool tank size is a limiting factor. It can be integrated as part of an existing purification process, after a column chromatography step or a filtration step, without introducing a new unit operation. In this study, SPTFF technology was systematically evaluated for reducing process intermediate volumes from 2× to 10× with multiple mAbs and the impact of SPTFF on product quality, and process yield was analyzed. Finally, the potential fit into the typical 3-column industry platform antibody purification process and its implementation in a commercial scale manufacturing facility were also evaluated. Our data indicate that using SPTFF to concentrate protein pools is a simple, flexible, and robust operation, which can be implemented at various scales to improve antibody purification process capacity. Copyright © 2011 Wiley Periodicals, Inc.

  4. Serial Killing of Tumor Cells by Human Natural Killer Cells – Enhancement by Therapeutic Antibodies

    Science.gov (United States)

    Bhat, Rauf; Watzl, Carsten

    2007-01-01

    Background Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. Methodology/Principal Findings We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of ‘exhausted’ NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. Conclusion/Significance Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies. PMID:17389917

  5. Serial killing of tumor cells by human natural killer cells--enhancement by therapeutic antibodies.

    Science.gov (United States)

    Bhat, Rauf; Watzl, Carsten

    2007-03-28

    Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of 'exhausted' NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies.

  6. Serial killing of tumor cells by human natural killer cells--enhancement by therapeutic antibodies.

    Directory of Open Access Journals (Sweden)

    Rauf Bhat

    Full Text Available BACKGROUND: Natural killer cells are an important component of the innate immune system. Anti-cancer therapies utilizing monoclonal antibodies also rely on the cytotoxicity of NK cells for their effectiveness. Here, we study the dynamics of NK cell cytotoxicity. METHODOLOGY/PRINCIPAL FINDINGS: We observe that IL-2 activated human NK cells can serially hit multiple targets. Using functional assays, we demonstrate that on an average, a single IL-2 activated NK cell can kill four target cells. Data using live video microscopy suggest that an individual NK cell can make serial contacts with multiple targets and majority of contacts lead to lysis of target cells. Serial killing is associated with a loss of Perforin and Granzyme B content. A large majority of NK cells survive serial killing, and IL-2 can replenish their granular stock and restore the diminished cytotoxicity of 'exhausted' NK cells. IL-2 and IL-15 are equally effective in enhancing the killing frequency of resting NK cells. Significantly, Rituximab, a therapeutic monoclonal antibody increases the killing frequency of both resting and IL-2 activated NK cells. CONCLUSION/SIGNIFICANCE: Our data suggest that NK cell-based therapies for overcoming tumors rely on their serial killing ability. Therefore, strategies augmenting the killing ability of NK cells can boost the immune system and enhance the effectiveness of monoclonal antibody-based therapies.

  7. Antibodies inside of a cell can change its outside: Can intrabodies provide a new therapeutic paradigm?

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    Andrea L.J. Marschall

    2016-01-01

    Full Text Available Challenges posed by complex diseases such as cancer, chronic viral infections, neurodegenerative disorders and many others have forced researchers to think beyond classic small molecule drugs, exploring new therapeutic strategies such as therapy with RNAi, CRISPR/Cas9 or antibody therapies as single or as combination therapies with existing drugs. While classic antibody therapies based on parenteral application can only reach extracellular targets, intracellular application of antibodies could provide specific advantages but is so far little recognized in translational research. Intrabodies allow high specificity and targeting of splice variants or post translational modifications. At the same time off target effects can be minimized by thorough biochemical characterization. Knockdown of cellular proteins by intrabodies has been reported for a significant number of disease-relevant targets, including ErbB-2, EGFR, VEGFR-2, Metalloproteinase MMP2 and MMP9, β-amyloid protein, α-synuclein, HIV gp120, HCV core and many others. This review outlines the recent advances in ER intrabody technology and their potential use in therapy.

  8. Impact of Shed/Soluble targets on the PK/PD of approved therapeutic monoclonal antibodies.

    Science.gov (United States)

    Samineni, Divya; Girish, Sandhya; Li, Chunze

    2016-12-01

    Suboptimal treatment for monoclonal antibodies (mAbs) directed against endogenous circulating soluble targets and the shed extracellular domains (ECD) of the membrane-bound targets is an important clinical concern due to the potential impact of mAbs on the in vivo efficacy and safety. Consequently, there are considerable challenges in the determination of an optimal dose and/or dosing regimen. Areas covered: This review outlines the impact of shed antigen targets from membrane-bound proteins and soluble targets on the PK and/or PD of therapeutic mAbs that have been approved in the last decade. We discuss various bioanalytical techniques that have facilitated the interpretation of the PK/PD properties of therapeutic mAbs and also considered the factors that may impact such measurements. Quantitative approaches include target-mediated PK models and bi- or tri-molecular interaction PK/PD models that describe the relationships between the antibody PK and the ensuing effects on PD biomarkers, to facilitate the mAb PK/PD characterization. Expert commentary: The proper interpretation of PK/PD relationships through the integrated PK/PD modeling and bioanalytical strategy facilitates a mechanistic understanding of the disease processes and dosing regimen optimization, thereby offering insights into developing effective therapeutic regimens. This review provides an overview of the impact of soluble targets or shed ECD on mAb PK/PD properties. We provide examples of quantitative approaches that facilitate the characterization of mAb PK/PD characteristics and their corresponding bioanalytical strategies.

  9. Solid phase-based cross-matching as solution for kidney allograft recipients pretreated with therapeutic antibodies.

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    Schlaf, Gerald; Apel, Susanne; Wahle, Anja; Altermann, Wolfgang W

    2015-01-01

    In order to select recipients without donor-specific anti-HLA antibodies, the complement-dependent cytotoxicity crossmatch (CDC-CM) was established as the standard procedure about 40 years ago. However, the interpretability of this functional assay strongly depends on the vitality of isolated donors' lymphocytes. Since the application of therapeutic antibodies for the immunosuppressive regimen falsifies the outcome of the CDC-crossmatch as a result of these antibodies' complement-activating capacity in the recipients' sera, we looked for an alternative methodical approach. We here present 27 examples of AB0 blood group-incompatible living kidney allograft recipients who, due to their treatment with the humanized chimeric monoclonal anti-CD20 antibody Rituximab, did not present valid outcomes of CDC-based pretransplant cross-matching. Additionally, four cases of posttransplant cross-matching after living kidney allografting and consequent treatment with the therapeutic anti-CD25 antibody Basiliximab (Simulect) due to acute biopsy-proven rejection episodes are presented and compared regarding CDC- and ELISA-based crossmatch outcomes. In all cases, it became evident that the classical CDC-based crossmatch was completely unfeasible for the detection of donor-specific anti-HLA antibodies, whereas ELISA-based cross-matching not requiring vital cells was not artificially affected. We conclude that ELISA-based cross-matching is a valuable tool to methodically circumvent false positive CDC-based crossmatch results in the presence of therapeutically applied antibodies.

  10. Semi-synthetic vNAR libraries screened against therapeutic antibodies primarily deliver anti-idiotypic binders.

    Science.gov (United States)

    Könning, Doreen; Rhiel, Laura; Empting, Martin; Grzeschik, Julius; Sellmann, Carolin; Schröter, Christian; Zielonka, Stefan; Dickgießer, Stephan; Pirzer, Thomas; Yanakieva, Desislava; Becker, Stefan; Kolmar, Harald

    2017-08-29

    Anti-idiotypic binders which specifically recognize the variable region of monoclonal antibodies have proven to be robust tools for pharmacokinetic studies of antibody therapeutics and for the development of cancer vaccines. In the present investigation, we focused on the identification of anti-idiotypic, shark-derived IgNAR antibody variable domains (vNARs) targeting the therapeutic antibodies matuzumab and cetuximab for the purpose of developing specific capturing ligands. Using yeast surface display and semi-synthetic, CDR3-randomized libraries, we identified several highly specific binders targeting both therapeutic antibodies in their corresponding variable region, without applying any counter selections during screening. Importantly, anti-idiotypic vNAR binders were not cross-reactive towards cetuximab or matuzumab, respectively, and comprised good target recognition in the presence of human and mouse serum. When coupled to magnetic beads, anti-idiotypic vNAR variants could be used as efficient capturing tools. Moreover, a two-step procedure involving vNAR-functionalized beads was employed for the enrichment of potentially bispecific cetuximab × matuzumab antibody constructs. In conclusion, semi-synthetic and CDR3-randomized vNAR libraries in combination with yeast display enable the fast and facile identification of anti-idiotypic vNAR domains targeting monoclonal antibodies primarily in an anti-idiotypic manner.

  11. Protocols for the analytical characterization of therapeutic monoclonal antibodies. II - Enzymatic and chemical sample preparation.

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    Bobaly, Balazs; D'Atri, Valentina; Goyon, Alexandre; Colas, Olivier; Beck, Alain; Fekete, Szabolcs; Guillarme, Davy

    2017-08-15

    The analytical characterization of therapeutic monoclonal antibodies and related proteins usually incorporates various sample preparation methodologies. Indeed, quantitative and qualitative information can be enhanced by simplifying the sample, thanks to the removal of sources of heterogeneity (e.g. N-glycans) and/or by decreasing the molecular size of the tested protein by enzymatic or chemical fragmentation. These approaches make the sample more suitable for chromatographic and mass spectrometric analysis. Structural elucidation and quality control (QC) analysis of biopharmaceutics are usually performed at intact, subunit and peptide levels. In this paper, general sample preparation approaches used to attain peptide, subunit and glycan level analysis are overviewed. Protocols are described to perform tryptic proteolysis, IdeS and papain digestion, reduction as well as deglycosylation by PNGase F and EndoS2 enzymes. Both historical and modern sample preparation methods were compared and evaluated using rituximab and trastuzumab, two reference therapeutic mAb products approved by Food and Drug Administration (FDA) and European Medicines Agency (EMA). The described protocols may help analysts to develop sample preparation methods in the field of therapeutic protein analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Defining New Therapeutics Using a More Immunocompetent Mouse Model of Antibody-Enhanced Dengue Virus Infection.

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    Pinto, Amelia K; Brien, James D; Lam, Chia-Ying Kao; Johnson, Syd; Chiang, Cindy; Hiscott, John; Sarathy, Vanessa V; Barrett, Alan D; Shresta, Sujan; Diamond, Michael S

    2015-09-15

    With over 3.5 billion people at risk and approximately 390 million human infections per year, dengue virus (DENV) disease strains health care resources worldwide. Previously, we and others established models for DENV pathogenesis in mice that completely lack subunits of the receptors (Ifnar and Ifngr) for type I and type II interferon (IFN) signaling; however, the utility of these models is limited by the pleotropic effect of these cytokines on innate and adaptive immune system development and function. Here, we demonstrate that the specific deletion of Ifnar expression on subsets of murine myeloid cells (LysM Cre(+) Ifnar(flox/flox) [denoted as Ifnar(f/f) herein]) resulted in enhanced DENV replication in vivo. The administration of subneutralizing amounts of cross-reactive anti-DENV monoclonal antibodies to LysM Cre(+) Ifnar(f/f) mice prior to infection with DENV serotype 2 or 3 resulted in antibody-dependent enhancement (ADE) of infection with many of the characteristics associated with severe DENV disease in humans, including plasma leakage, hypercytokinemia, liver injury, hemoconcentration, and thrombocytopenia. Notably, the pathogenesis of severe DENV-2 or DENV-3 infection in LysM Cre(+) Ifnar(f/f) mice was blocked by pre- or postexposure administration of a bispecific dual-affinity retargeting molecule (DART) or an optimized RIG-I receptor agonist that stimulates innate immune responses. Our findings establish a more immunocompetent animal model of ADE of infection with multiple DENV serotypes in which disease is inhibited by treatment with broad-spectrum antibody derivatives or innate immune stimulatory agents. Although dengue virus (DENV) infects hundreds of millions of people annually and results in morbidity and mortality on a global scale, there are no approved antiviral treatments or vaccines. Part of the difficulty in evaluating therapeutic candidates is the lack of small animal models that are permissive to DENV and recapitulate the clinical features

  13. The Therapeutic Value of Monoclonal Antibodies Directed Against Immunogenic Tumor Glycoproteins

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    Myron Arlen, Philip Arlen, Al Tsang, XuePing Wang, Rishab Gupta

    2010-01-01

    Full Text Available Monoclonal antibodies developed against immunogenic proteins (Tumor Specific Antigens/TSA's that are expressed in human cancers, display a unique behavioral pattern. They appear to serve in a dual role. This includes the early recognition of these immunogenic membrane proteins that can serve as diagnostic markers, and the targeting of such markers for the destruction of the tumor, primarily thru ADCC.The monoclonals (mAbs that we have developed against specific immunogenic tumor membrane proteins have been studied in detail. These tumor proteins, when first defined, were referred to as tumor associated antigens. With the ability of the mAbs to demonstrate therapeutic antitumor activity in those patients with relatively advanced malignancies, the term tumor specific was introduced. Monoclonals that we were able to develop from tumor specific proteins derived from colon and pancreas cancer were found capable of targeting those tumors to induce apoptosis. We were also able to define immunogenic membrane proteins from lung (squamous and adenoCa as well as prostate neoplasms. Monoclonals developed from these tumor antigens are in the initial phases of investigation with regard to their specificity and antitumor activity.Mabs capable of targeting the malignancies noted above were produced following immunization of BALBc mice with the Tumor Specific Antigens. The hybridomas that were screened and found to express the antibodies of interest appeared for the most part as IgG2a's. It became apparent after a short period of time that stability of the Fab CDR loops as well as the therapeutic efficacy of the hybridoma mAbs could be lost. Stability was achieved by chimerization and or humanization. The resulting mAbs were found to switch their isotypes to an IgG1 subsequent to chimerization and or humanization, when expressed in CHO cells. The monoclonals, so produced, were not only more efficient in controlling tumor growth but minimized the development of a

  14. Comparison of two therapeutic protocols in patients with antiphospholipid antibodies and recurrent miscariages

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    Jeremić Katarina

    2005-01-01

    Full Text Available Aim. To compare the effects of two therapeutic protocols for the patients with recurrent miscarriages associated with the presence of antiphospholipid (anticardiolipin antibodies. Methods. A prospective observational study included 20 patients with antiphospholipid antibodies in the first group who received low-molecular heparin and aspirin. The second group of 20 patients, in addition to this therapy, received immunotherapy (intravenous immunoglobulin. Aspirin was administered at the time of a positive pregnancy test, and low molecular heparin not before the fetal heart activity registration by ultrasound. Intravenous immunoglobulin was given prior to the conception or at the beginning of the pregnancy. We compared these groups according to the pregnancy outcomes and the occurrence of complications during pregnancy, using standard statistical tests. Results. The rate of positive gestational outcome in the patients treated with aspirin and low-molecular heparin was 85% (17/20, and in the second group it was 90% (18/20. There was no significant difference in pregnancy outcomes between these groups (p > 0.05, except for the occurrence of preeclampsia and thrombocytopenia, which were recorded only in the aspirin and low-molecular heparin group, but with no statistical significance (p > 0.05 compared to the second group, which received immunoglobulin additionally. Conclusion. There was no significant difference (p > 0.05 in pregnancy outcomes between the two studied therapeutic protocols, but the therapy with aspirin and low-molecular heparin was cheaper and easier to apply than the therapy with immunoglobulins. The results of our study confirmed that the final pathogenic mechanisms in recurrent fetal miscarriages were inflammation and thrombosis of the uteroplacental blood vessels.

  15. Structural characterization of a therapeutic anti-methamphetamine antibody fragment: oligomerization and binding of active metabolites.

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    Eric C Peterson

    Full Text Available Vaccines and monoclonal antibodies (mAb for treatment of (+-methamphetamine (METH abuse are in late stage preclinical and early clinical trial phases, respectively. These immunotherapies work as pharmacokinetic antagonists, sequestering METH and its metabolites away from sites of action in the brain and reduce the rewarding and toxic effects of the drug. A key aspect of these immunotherapy strategies is the understanding of the subtle molecular interactions important for generating antibodies with high affinity and specificity for METH. We previously determined crystal structures of a high affinity anti-METH therapeutic single chain antibody fragment (scFv6H4, K(D = 10 nM in complex with METH and the (+ stereoisomer of 3,4-methylenedioxymethamphetamine (MDMA, or "ecstasy". Here we report the crystal structure of scFv6H4 in homo-trimeric unbound (apo form (2.60Å, as well as monomeric forms in complex with two active metabolites; (+-amphetamine (AMP, 2.38Å and (+-4-hydroxy methamphetamine (p-OH-METH, 2.33Å. The apo structure forms a trimer in the crystal lattice and it results in the formation of an intermolecular composite beta-sheet with a three-fold symmetry. We were also able to structurally characterize the coordination of the His-tags with Ni(2+. Two of the histidine residues of each C-terminal His-tag interact with Ni(2+ in an octahedral geometry. In the apo state the CDR loops of scFv6H4 form an open conformation of the binding pocket. Upon ligand binding, the CDR loops adopt a closed formation, encasing the drug almost completely. The structural information reported here elucidates key molecular interactions important in anti-methamphetamine abuse immunotherapy.

  16. Intracellular reprogramming of expression, glycosylation, and function of a plant-derived antiviral therapeutic monoclonal antibody.

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    Jeong-Hwan Lee

    Full Text Available Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAb(Ps, provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAb(P SO57 with or without an endoplasmic reticulum (ER-retention peptide signal (Lys-Asp-Glu-Leu; KDEL in transgenic tobacco plants (Nicotiana tabacum were analyzed. The expression levels of mAb(P SO57 with KDEL (mAb(PK were significantly higher than those of mAb(P SO57 without KDEL (mAb(P regardless of the transcription level. The Fc domains of both purified mAb(P and mAb(PK and hybridoma-derived mAb (mAb(H had similar levels of binding activity to the FcγRI receptor (CD64. The mAb(PK had glycan profiles of both oligomannose (OM type (91.7% and Golgi type (8.3%, whereas the mAb(P had mainly Golgi type glycans (96.8% similar to those seen with mAb(H. Confocal analysis showed that the mAb(PK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAb(P with KDEL in the ER. Both mAb(P and mAb(PK disappeared with similar trends to mAb(H in BALB/c mice. In addition, mAb(PK was as effective as mAb(H at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAb(P by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant.

  17. Intracellular Reprogramming of Expression, Glycosylation, and Function of a Plant-Derived Antiviral Therapeutic Monoclonal Antibody

    Science.gov (United States)

    Lee, Kyung-Jin; Kim, Young-Kwan; So, Yang-Kang; Ryu, Jae-Sung; Oh, Seung-Han; Han, Yeon-Soo; Ko, Kinarm; Choo, Young-Kug; Park, Sung-Joo; Brodzik, Robert; Lee, Kyoung-Ki; Oh, Doo-Byoung; Hwang, Kyung-A; Koprowski, Hilary; Lee, Yong Seong; Ko, Kisung

    2013-01-01

    Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAbPs), provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAbP SO57 with or without an endoplasmic reticulum (ER)-retention peptide signal (Lys-Asp-Glu-Leu; KDEL) in transgenic tobacco plants (Nicotiana tabacum) were analyzed. The expression levels of mAbP SO57 with KDEL (mAbPK) were significantly higher than those of mAbP SO57 without KDEL (mAbP) regardless of the transcription level. The Fc domains of both purified mAbP and mAbPK and hybridoma-derived mAb (mAbH) had similar levels of binding activity to the FcγRI receptor (CD64). The mAbPK had glycan profiles of both oligomannose (OM) type (91.7%) and Golgi type (8.3%), whereas the mAbP had mainly Golgi type glycans (96.8%) similar to those seen with mAbH. Confocal analysis showed that the mAbPK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAbP with KDEL in the ER. Both mAbP and mAbPK disappeared with similar trends to mAbH in BALB/c mice. In addition, mAbPK was as effective as mAbH at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAbP by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant. PMID:23967055

  18. Protocols for the analytical characterization of therapeutic monoclonal antibodies. I - Non-denaturing chromatographic techniques.

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    Goyon, Alexandre; D'Atri, Valentina; Bobaly, Balazs; Wagner-Rousset, Elsa; Beck, Alain; Fekete, Szabolcs; Guillarme, Davy

    2017-07-15

    Size-, charge- and hydrophobicity-related variants of a biopharmaceutical product have to be deeply characterized for batch consistency and for the assessment of immunogenicity and safety effects. Size exclusion chromatography (SEC) and ion exchange chromatography (IEX) are considered as the gold standard for the analysis of high molecular weight species (HMWS) and charge-related variants, respectively. Hydrophobic interaction chromatography (HIC) has drawn renewed attention to monitor the small drug payload distribution in the cysteine-linked antibody-drug conjugates (ADC). These three chromatographic techniques, namely SEC, HIC and IEX, are historical, non-denaturing and robust approaches widely used for the characterization of biopharmaceutical proteins. Despite the broad spectrum of monoclonal antibodies (mAbs) structures, isoelectric points (pIs) and hydrophobicities, generic protocols can be applied to separate their size-, charge- and hydrophobicity-related variants, using the last generation of chromatographic columns and appropriate mobile phase conditions. Straightforward protocols are described in this manuscript with representative chromatograms of ten distinct Food and Drug Administration (FDA) and European Medicines Agency (EMA) approved therapeutic mAb products to illustrate the performance of the SEC, IEX and HIC methods. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Microencapsulation of therapeutic bispecific antibodies producing cells: immunotherapeutic organoids for cancer management.

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    Saenz del Burgo, Laura; Compte, Marta; Aceves, Mónica; Hernández, Rosa María; Sanz, Laura; Álvarez-Vallina, Luis; Pedraz, Jose Luis

    2015-02-01

    Regardless of the important therapeutic advances developed over the last years for the management of cancer, the fact is that many patients still suffer from a tremendous reduction on their quality of life due to lack of complete selectivity of conventionally administered chemotherapeutic drugs. In the search of more efficacious tumor-targeted therapies, the use of bispecific antibodies (bsAbs) capable of simultaneous binding to tumor-associated antigens and to an activating receptor, such as CD3, has emerged as a promising approach. With the intention to complementing and improving this cancer immunotherapy, human HEK-293 cells have been genetically modified ex vivo to secrete a recombinant anti-CEA (carcinoembryonic antigen) × anti-CD3 bsAb. After encapsulation in alginate-poly-l-lysine microcapsules, bsAb-secreting HEK-293 cells were monitorized for several weeks. This system has proved to be feasible for the maintenance of cell growth and recombinant antibody production giving proof-of-concept of its use as immunotherapeutic organoids in cancer treatment.

  20. An extended range generic immunoassay for total human therapeutic antibodies in preclinical pharmacokinetic studies.

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    Hall, Colin M; Pearson, Josh T; Patel, Vimal; Wienkers, Larry C; Greene, Robert J

    2013-07-31

    Bioanalytical support of discovery programs for human monoclonal antibody therapies involves quantitation by immunoassay. Historically, preclinical samples have been analyzed by the traditional Enzyme-Linked Immuno-Sorbent Assay (ELISA). We investigated transferring our generic ELISA for quantitating human IgG constructs in preclinical serum samples to an automated microfluidics immunoassay platform based on nanoscale streptavidin bead columns. Transfer of our immunoassay to the automated platform resulted in not only the anticipated reduction in analysts' time required for manual manipulation (ELISA) but also a substantial increase in the dynamic range of the immunoassay. The generic nature and wide dynamic range of this automated microcolumn immunoassay permit bioanalytical support of novel therapeutic candidates without the need to develop new, specific assay reagents and minimize the chances that sample reassays will be required due to out of range concentration results. Improved process efficiencies and enhanced workflow during the analysis of preclinical PK samples that enable high throughput assessment of a human monoclonal antibody lead in early discovery programs. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Small amounts of sub-visible aggregates enhance the immunogenic potential of monoclonal antibody therapeutics.

    Science.gov (United States)

    Ahmadi, Maryam; Bryson, Christine J; Cloake, Edward A; Welch, Katie; Filipe, Vasco; Romeijn, Stefan; Hawe, Andrea; Jiskoot, Wim; Baker, Matthew P; Fogg, Mark H

    2015-04-01

    Determine the effect of minute quantities of sub-visible aggregates on the in vitro immunogenicity of clinically relevant protein therapeutics. Monoclonal chimeric (rituximab) and humanized (trastuzumab) antibodies were subjected to fine-tuned stress conditions to achieve low levels (aggregates. The effect of stimulating human dendritic cells (DC) and CD4(+) T cells with the aggregates was measured in vitro using cytokine secretion, proliferation and confocal microscopy. Due to its intrinsic high clinical immunogenicity, aggregation of rituximab had minimal effects on DC activation and T cell responses compared to monomeric rituximab. However, in the case of trastuzumab (low clinical immunogenicity) small quantities of aggregates led to potent CD4(+) T cell proliferation as a result of strong cytokine and co-stimulatory signals derived from DC. Consistent with this, confocal studies showed that stir-stressed rituximab was rapidly internalised and associated with late endosomes of DC. These data link minute amounts of aggregates with activation of the innate immune response, involving DC, resulting in T cell activation. Thus, when protein therapeutics with little or no clinical immunogenicity, such as trastuzumab, contain minute amounts of sub-visible aggregates, they are associated with significantly increased potential risk of clinical immunogenicity.

  2. Epithelial cell-adhesion molecule-directed trifunctional antibody immunotherapy for symptom management of advanced ovarian cancer

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    Eskander RN

    2013-10-01

    Full Text Available Ramez N Eskander, Krishnansu S Tewari Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of California, Irvine, CA, USA Abstract: Despite advances in cytotoxic chemotherapy and surgical cytoreduction, disease recurrence continues to be a troubling problem in patients with advanced-stage epithelial ovarian cancer (EOC. Malignant ascites affects approximately 10% of patients with recurrent EOC and is associated with troublesome symptoms, including abdominal pressure, distension, dyspnea, pelvic pain, and bowel/bladder dysfunction. To date, no effective therapy has been identified for the treatment of malignant ascites in patients with recurrent, advanced-stage ovarian cancer. Recently, immune modulation has gained attention as a novel approach to anti-cancer therapy. This review explores the role of epithelial cell-adhesion molecule (EpCAM-directed immunotherapy, with a specific focus on the mechanism of action of the trifunctional antibody catumaxomab (anti-EpCAM × anti-CD3. In addition, clinical trials exploring the use of catumaxomab in the treatment of malignant ascites in patients with ovarian cancer are reviewed. Keywords: ovarian cancer, immunotherapy, catumaxomab, CD3, EpCAM

  3. Camelid Ig V genes reveal significant human homology not seen in therapeutic target genes, providing for a powerful therapeutic antibody platform

    Science.gov (United States)

    Klarenbeek, Alex; Mazouari, Khalil El; Desmyter, Aline; Blanchetot, Christophe; Hultberg, Anna; de Jonge, Natalie; Roovers, Rob C; Cambillau, Christian; Spinelli, Sylvia; Del-Favero, Jurgen; Verrips, Theo; de Haard, Hans J; Achour, Ikbel

    2015-01-01

    Camelid immunoglobulin variable (IGV) regions were found homologous to their human counterparts; however, the germline V repertoires of camelid heavy and light chains are still incomplete and their therapeutic potential is only beginning to be appreciated. We therefore leveraged the publicly available HTG and WGS databases of Lama pacos and Camelus ferus to retrieve the germline repertoire of V genes using human IGV genes as reference. In addition, we amplified IGKV and IGLV genes to uncover the V germline repertoire of Lama glama and sequenced BAC clones covering part of the Lama pacos IGK and IGL loci. Our in silico analysis showed that camelid counterparts of all human IGKV and IGLV families and most IGHV families could be identified, based on canonical structure and sequence homology. Interestingly, this sequence homology seemed largely restricted to the Ig V genes and was far less apparent in other genes: 6 therapeutically relevant target genes differed significantly from their human orthologs. This contributed to efficient immunization of llamas with the human proteins CD70, MET, interleukin (IL)-1β and IL-6, resulting in large panels of functional antibodies. The in silico predicted human-homologous canonical folds of camelid-derived antibodies were confirmed by X-ray crystallography solving the structure of 2 selected camelid anti-CD70 and anti-MET antibodies. These antibodies showed identical fold combinations as found in the corresponding human germline V families, yielding binding site structures closely similar to those occurring in human antibodies. In conclusion, our results indicate that active immunization of camelids can be a powerful therapeutic antibody platform. PMID:26018625

  4. Characterization of a Type-Common Human Recombinant Monoclonal Antibody to Herpes Simplex Virus with High Therapeutic Potential

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    De Logu, Alessandro; Williamson, R. Anthony; Rozenshteyn, Roman; Ramiro-Ibañez, Fernando; Simpson, Cindy D.; Burton, Dennis R.; Paolo Sanna, Pietro

    1998-01-01

    We report the characterization of a type-common human recombinant monoclonal antibody previously isolated by antigen selection from a phage-displayed combinatorial antibody library established from a herpes simplex virus (HSV)-seropositive individual. Competition with well-characterized murine monoclonal antibodies and immunodetection of gD truncations revealed that this antibody recognizes the group Ib antigenic site of glycoprotein D, a highly conserved and protective type-common determinant. To our knowledge, this is the first human group Ib monoclonal antibody ever described. The antibody also displayed first-order neutralization kinetics and a high neutralization rate constant, was capable of completely inhibiting syncytium formation by a fusogenic strain of HSV type 1, and efficiently neutralized low-passage clinical isolates of both HSV serotypes. Taken together with our earlier observations of the in vivo antiviral activities of this human recombinant antibody in animal models of HSV infection, the present results support the high therapeutic potential of this antibody. PMID:9774565

  5. Correlation of pharmacodynamic activity, pharmacokinetics, and anti-product antibody responses to anti-IL-21R antibody therapeutics following IV administration to cynomolgus monkeys

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    Spaulding Vikki

    2010-04-01

    Full Text Available Abstract Background Anti-IL-21R antibodies are potential therapeutics for the treatment of autoimmune diseases. This study evaluated correlations between the pharmacodynamic (PD activity, pharmacokinetics, and anti-product antibody responses of human anti-IL-21R antibodies Ab-01 and Ab-02 following IV administration to cynomolgus monkeys. Methods The PD assay was based on the ability of recombinant human IL-21 (rhuIL-21 to induce expression of the IL-2RA gene in cynomolgus monkey whole blood samples ex vivo. Monkeys screened for responsiveness to rhuIL-21 stimulation using the PD assay, were given a single 10 mg/kg IV dosage of Ab-01, Ab-02, or a control antibody (3/group, and blood samples were evaluated for PD activity (inhibition of IL-2RA expression for up to 148 days. Anti-IL-21R antibody concentrations and anti-product antibody responses were measured in serum using immunoassays and flow cytometry. Results Following IV administration of Ab-01 and Ab-02 to cynomolgus monkeys, PD activity was observed as early as 5 minutes (first time point sampled. This PD activity had good correlation with the serum concentrations and anti-product antibody responses throughout the study. The mean terminal half-life (t1/2 was ~10.6 and 2.3 days for Ab-01 and Ab-02, respectively. PD activity was lost at ~5-13 weeks for Ab-01 and at ~2 weeks for Ab-02, when serum concentrations were relatively low. The estimated minimum concentrations needed to maintain PD activity were ~4-6 nM for Ab-01 and ~2.5 nM for Ab-02, and were consistent with the respective KD values for binding to human IL-21R. For Ab-01, there was noticeable inter-animal variability in t1/2 values (~6-14 days and the resulting PD profiles, which correlated with the onset of anti-product antibody formation. While all three Ab-01-dosed animals were positive for anti-Ab-01 antibodies, only one monkey (with the shortest t1/2 and the earliest loss of PD activity had evidence of neutralizing anti-Ab-01

  6. Optimization of heavy chain and light chain signal peptides for high level expression of therapeutic antibodies in CHO cells.

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    Ryan Haryadi

    Full Text Available Translocation of a nascent protein from the cytosol into the ER mediated by its signal peptide is a critical step in protein secretion. The aim of this work was to develop a platform technology to optimize the signal peptides for high level production of therapeutic antibodies in CHO cells. A database of signal peptides from a large number of human immunoglobulin (Ig heavy chain (HC and kappa light chain (LC was generated. Most of the HC signal peptides contain 19 amino acids which can be divided into three domains and the LC signal peptides contain 22 amino acids. The signal peptides were then clustered according to sequence similarity. Based on the clustering, 8 HC and 2 LC signal peptides were analyzed for their impacts on the production of 5-top selling antibody therapeutics, namely, Herceptin, Avastin, Remicade, Rituxan, and Humira. The best HC and LC signal peptides for producing these 5 antibodies were identified. The optimized signal peptides for Rituxan is 2-fold better compared to its native signal peptides which are available in the public database. Substitution of a single amino acid in the optimized HC signal peptide for Avastin reduced its production significantly. Mass spectrometry analyses revealed that all optimized signal peptides are accurately removed in the mature antibodies. The results presented in this report are particularly important for the production of these 5 antibodies as biosimilar drugs. They also have the potential to be the best signal peptides for the production of new antibodies in CHO cells.

  7. Antibody

    Science.gov (United States)

    An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples ... microorganisms (bacteria, fungi, parasites, and viruses) and chemicals. Antibodies may be produced when the immune system mistakenly ...

  8. Immunoglobulin Fc heterodimer platform technology: From design to applications in therapeutic antibodies and proteins

    Directory of Open Access Journals (Sweden)

    Ji-Hee Ha

    2016-10-01

    Full Text Available The monospecific and bivalent characteristics of naturally occurring immunoglobulin G (IgG antibodies depend on homodimerization of the fragment crystallizable (Fc regions of two identical heavy chains (HCs and the subsequent assembly of two identical light chains (LCs via disulfide linkages between each HC and LC. Immunoglobulin Fc heterodimers have been engineered through modifications to the CH3 domain interface, with different mutations on each domain such that the engineered Fc fragments, carrying the CH3 variant pair, preferentially form heterodimers rather than homodimers. Many research groups have adopted different strategies to generate Fc heterodimers, with the goal of high heterodimerization yield, while retaining biophysical and biological properties of the wild-type Fc. Based on their ability to enforce heterodimerization between the two different HCs, the established Fc heterodimers have been extensively exploited as a scaffold to generate bispecific antibodies (bsAbs in full-length IgG and IgG-like formats. These have many of the favorable properties of natural IgG antibodies, such as high stability, long serum half-life, low immunogenicity, and immune effector functions. As of July 2016, more than seven heterodimeric Fc-based IgG-format bsAbs are being evaluated in clinical trials. In addition to bsAbs, heterodimeric Fc technology is very promising for the generation of Fc-fused proteins and peptides, as well as cytokines (immunocytokines, which can present the fusion partners in the natural monomeric or heterodimeric form rather than the artificial homodimeric form with wild-type Fc. Here, we present relevant concepts and strategies for the generation of heterodimeric Fc proteins, and their application in the development of bsAbs in diverse formats for optimal biological activity. In addition, we describe wild type Fc-fused monomeric and heterodimeric proteins, along with the difficulties associated with their preparations, and

  9. Optimized nonclinical safety assessment strategies supporting clinical development of therapeutic monoclonal antibodies targeting inflammatory diseases.

    Science.gov (United States)

    Brennan, Frank R; Cauvin, Annick; Tibbitts, Jay; Wolfreys, Alison

    2014-05-01

    An increasing number of immunomodulatory monoclonal antibodies (mAbs) and IgG Fc fusion proteins are either approved or in early-to-late stage clinical trials for the treatment of chronic inflammatory conditions, autoimmune diseases and organ transplant rejection. The exquisite specificity of mAbs, in combination with their multi-functional properties, high potency, long half-life (permitting intermittent dosing and prolonged pharamcological effects), and general lack of off-target toxicity makes them ideal therapeutics. Dosing with mAbs for these severe and debilitating but often non life-threatening diseases is usually prolonged, for several months or years, and not only affects adults, including sensitive populations such as woman of child-bearing potential (WoCBP) and the elderly, but also children. Immunosuppression is usually a therapeutic goal of these mAbs and when administered to patients whose treatment program often involves other immunosuppressive therapies, there is an inherent risk for frank immunosuppression and reduced host defence which when prolonged increases the risk of infection and cancer. In addition when mAbs interact with the immune system they can induce other adverse immune-mediated drug reactions such as infusion reactions, cytokine release syndrome, anaphylaxis, immune-complex-mediated pathology and autoimmunity. An overview of the nonclinical safety assessment and risk mitigation strategies utilized to characterize these immunomodulatory mAbs and Fc fusion proteins to support first-in human (FIH) studies and futher clinical development in inflammatory disease indications is provided. Specific emphasis is placed on the design of studies to qualify animal species for toxicology studies, early studies to investigate safety and define PK/PD relationships, FIH-enabling and chronic toxicology studies, immunotoxicity, developmental, reproductive and juvenile toxicity studies and studies to determine the potential for immunosuppression and

  10. Non-viral adeno-associated virus-based platform for stable expression of antibody combination therapeutics.

    Science.gov (United States)

    Wilmes, Gwendolyn M; Carey, Kimberly L; Hicks, Stuart W; Russell, Hugh H; Stevenson, Jesse A; Kocjan, Paulina; Lutz, Stephen R; Quesenberry, Rachel S; Shulga-Morskoy, Sergey V; Lewis, Megan E; Clark, Ethan; Medik, Violetta; Cooper, Anthony B; Reczek, Elizabeth E

    2014-01-01

    Antibody combination therapeutics (ACTs) are polyvalent biopharmaceuticals that are uniquely suited for the control of complex diseases, including antibiotic resistant infectious diseases, autoimmune disorders and cancers. However, ACTs also represent a distinct manufacturing challenge because the independent manufacture and subsequent mixing of monoclonal antibodies quickly becomes cost prohibitive as more complex mixtures are envisioned. We have developed a virus-free recombinant protein expression platform based on adeno-associated viral (AAV) elements that is capable of rapid and consistent production of complex antibody mixtures in a single batch format. Using both multiplexed immunoassays and cation exchange (CIEX) chromatography, cell culture supernatants generated using our system were assessed for stability of expression and ratios of the component antibodies over time. Cultures expressing combinations of three to ten antibodies maintained consistent expression levels and stable ratios of component antibodies for at least 60 days. Cultures showed remarkable reproducibility following cell banking, and AAV-based cultures showed higher stability and productivity than non-AAV based cultures. Therefore, this non-viral AAV-based expression platform represents a predictable, reproducible, quick and cost effective method to manufacture or quickly produce for preclinical testing recombinant antibody combination therapies and other recombinant protein mixtures.

  11. Antibody therapeutics for treating prostate cancer: where are we now and what comes next?

    Science.gov (United States)

    Vlachostergios, Panagiotis J; Galletti, Giuseppe; Palmer, Jessica; Lam, Linda; Karir, Beerinder S; Tagawa, Scott T

    2017-02-01

    Progress in the understanding of molecular events of carcinogenesis and cancer evolution as well as the identification of tumor antigens has led to the development of different targeted therapeutic approaches, including the use of monoclonal antibodies (mAbs). Prostate cancer (PC) is highly amenable to mAb targeting given the existence of prostate-specific targets and the natural history and localization of metastatic disease. Areas covered: Several aspects of the PC phenotype, including growth factors, angiogenesis mediators, bone microenvironment signals, and immune evasion pathways, have become areas of ongoing investigation in terms of mAb targeting. These are reviewed. The greatest success so far has been the development of mAbs against prostate-specific tumor antigen (PSMA), which opened an opportunity to improve diagnostic accuracy and simultaneously target metastatic disease. Expert opinion: As mAb use in PC continues to evolve, more accurate imaging of the extent of disease and more effective mAb therapies (naked or conjugated with drugs, toxins or radioactive molecules) are emerging. In addition, the combination of mAbs with other treatment modalities is expected to further improve responses and overall survival. Identification of validated biomarkers is necessary for better recognition of patient subgroups who will derive the greatest benefit from mAb therapy.

  12. Llama single-chain antibody that blocks lipopolysaccharide binding and signaling: prospects for therapeutic applications.

    Science.gov (United States)

    El Khattabi, Mohamed; Adams, Hendrik; Heezius, Erik; Hermans, Pim; Detmers, Frank; Maassen, Bram; van der Ley, Peter; Tommassen, Jan; Verrips, Theo; Stam, Jord

    2006-10-01

    Sepsis is a considerable health problem and a burden on the health care system. Endotoxin, or lipopolysaccharide (LPS), present in the outer membrane of gram-negative bacteria, is responsible for more than 50% of the sepsis cases and is, therefore, a legitimate target for therapeutic approaches against sepsis. In this study, we selected and characterized a llama single-chain antibody fragment (VHH) directed to Neisseria meningitidis LPS. The VHH, designated VHH 5G, showed affinity to purified LPS as well as to LPS on the surfaces of the bacteria. Epitope mapping using a panel of N. meningitidis mutants revealed that VHH 5G recognizes an epitope in the inner core of LPS, and as expected, the VHH proved to have broad specificity for LPS from different bacteria. Furthermore, this VHH blocked binding of LPS to target cells of the immune system, resulting in the inhibition of LPS signaling in whole blood. Moreover, it was found to remove LPS efficiently from aqueous solutions, including serum. The selected anti-LPS VHH is a leading candidate for therapies against LPS-mediated sepsis.

  13. Scaling-Up and Production of Therapeutic Antibodies for Preclinical Studies

    OpenAIRE

    Feng, Yang; Dimitrov, Dimiter S

    2009-01-01

    Monoclonal antibodies are increasingly used for treatment of various diseases, mostly cancer therapy and auto-immune diseases. New chimeric, humanized, or fully-human antibodies specific to novel or already validated targets are being developed in many academic labs as well as in commercial entities. A validation of antibodies in preclinical settings is an important component of the road from discovery to clinic. Preparing sufficient amount of high-quality antibodies for preclinical studies i...

  14. Structural Basis for Treating Tumor Necrosis Factor α (TNFα)-associated Diseases with the Therapeutic Antibody Infliximab*

    Science.gov (United States)

    Liang, Shuaiyi; Dai, Jianxin; Hou, Sheng; Su, Lishu; Zhang, Dapeng; Guo, Huaizu; Hu, Shi; Wang, Hao; Rao, Zihe; Guo, Yajun; Lou, Zhiyong

    2013-01-01

    Monoclonal antibody (mAb) drugs have been widely used for treating tumor necrosis factor α (TNFα)-related diseases for over 10 years. Although their action has been hypothesized to depend in part on their ability to bind precursor cell surface TNFα, the precise mechanism and the epitope bound on TNFα remain unclear. In the present work, we report the crystal structure of the infliximab Fab fragment in complex with TNFα at a resolution of 2.6 Å. The key features of the TNFα E-F loop region in this complex distinguish the interaction between infliximab and TNFα from other TNF-receptor structures, revealing the mechanism of TNFα inhibition by overlapping with the TNFα-receptor interface and indicating the crucial role of the E-F loop in the action of this therapeutic antibody. This structure also indicates the formation of an aggregated network for the activation of complement-dependent cytolysis and antibody-dependent cell-mediated cytotoxicity, which result in development of granulomatous infections through TNFα blockage. These results provide the first experimental model for the interaction of TNFα with therapeutic antibodies and offer useful information for antibody optimization by understanding the precise molecular mechanism of TNFα inhibition. PMID:23504311

  15. Serum trough infliximab and anti-infliximab antibodies in a cohort of gastroenterology and rheumatology patients' infliximab therapeutic drug monitoring.

    Science.gov (United States)

    Barlow, Nicola L; Mohammed, Pervaz; Berg, Jonathan D

    2016-07-01

    Infliximab, a monoclonal antibody directed against tumour necrosis factor, is widely used in the treatment of chronic inflammatory conditions including Crohn's disease and rheumatoid arthritis. Its use is limited by development of anti-infliximab antibodies, which can lead to loss of therapeutic efficacy. Serum infliximab and anti-infliximab antibody measurements have recently become routinely available in the UK. The study aimed to assess the clinical utility of antibodies as an adjunct to trough infliximab. Serum trough infliximab was measured in 201 samples from 108 gastroenterology and rheumatology patients on maintenance infliximab therapy. Results were correlated with C-reactive protein concentrations. Total anti-infliximab antibodies were measured in 164 samples. The median (25th-75th percentile) trough infliximab was 3.7 µg/mL (1.2-5.2 µg/mL) and 23% of samples had a concentration ≤1 µg/mL. A notable proportion had positive anti-infliximab antibodies: 84/164 (51%), which subdivided to 85% and 28% with infliximab ≤1 and >1 µg/mL, respectively.Serum C-reactive protein was found to be significantly higher where infliximab was ≤1 compared to >1 µg/mL (10 mg/L [infliximab and C-reactive protein differed depending on antibody status and there was no association between C-reactive protein and the presence or absence of antibodies. Our findings support measurement of anti-infliximab antibodies only in the context of low infliximab concentrations infliximab concentrations. © The Author(s) 2015.

  16. Chimeric antibody c.8B6 to O-acetyl-GD2 mediates the same efficient anti-neuroblastoma effects as therapeutic ch14.18 antibody to GD2 without antibody induced allodynia.

    Directory of Open Access Journals (Sweden)

    Mickaël Terme

    Full Text Available BACKGROUND: Anti-GD2 antibody is a proven therapy for GD2-positive neuroblastoma. Monoclonal antibodies against GD2, such as chimeric mAb ch14.18, have become benchmarks for neuroblastoma therapies. Pain, however, can limit immunotherapy with anti-GD2 therapeutic antibodies like ch14.18. This adverse effect is attributed to acute inflammation via complement activation on GD2-expressing nerves. Thus, new strategies are needed for the development of treatment intensification strategies to improve the outcome of these patients. METHODOLOGY/PRINCIPAL FINDINGS: We established the mouse-human chimeric antibody c.8B6 specific to OAcGD2 in order to reduce potential immunogenicity in patients and to fill the need for a selective agent that can kill neuroblastoma cells without inducing adverse neurological side effects caused by anti-GD2 antibody immunotherapy. We further analyzed some of its functional properties compared with anti-GD2 ch14.18 therapeutic antibody. With the exception of allodynic activity, we found that antibody c.8B6 shares the same anti-neuroblastoma attributes as therapeutic ch14.18 anti-GD2 mAb when tested in cell-based assay and in vivo in an animal model. CONCLUSION/SIGNIFICANCE: The absence of OAcGD2 expression on nerve fibers and the lack of allodynic properties of c.8B6-which are believed to play a major role in mediating anti-GD2 mAb dose-limiting side effects-provide an important rationale for the clinical application of c.8B6 in patients with high-risk neuroblastoma.

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

    Science.gov (United States)

    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. Therapeutic Antibodies: What Have We Learnt from Targeting CD20 and Where Are We Going?

    Directory of Open Access Journals (Sweden)

    Michael J. E. Marshall

    2017-10-01

    Full Text Available Therapeutic monoclonal antibodies (mAbs have become one of the fastest growing classes of drugs in recent years and are approved for the treatment of a wide range of indications, from cancer to autoimmune disease. Perhaps the best studied target is the pan B-cell marker CD20. Indeed, the first mAb to receive approval by the Food and Drug Administration for use in cancer treatment was the CD20-targeting mAb rituximab (Rituxan®. Since its approval for relapsed/refractory non-Hodgkin’s lymphoma in 1997, rituximab has been licensed for use in the treatment of numerous other B-cell malignancies, as well as autoimmune conditions, including rheumatoid arthritis. Despite having a significant impact on the treatment of these patients, the exact mechanisms of action of rituximab remain incompletely understood. Nevertheless, numerous second- and third-generation anti-CD20 mAbs have since been developed using various strategies to enhance specific effector functions thought to be key for efficacy. A plethora of knowledge has been gained during the development and testing of these mAbs, and this knowledge can now be applied to the design of novel mAbs directed to targets beyond CD20. As we enter the “post-rituximab” era, this review will focus on the lessons learned thus far through investigation of anti-CD20 mAb. Also discussed are current and future developments relating to enhanced effector function, such as the ability to form multimers on the target cell surface. These strategies have potential applications not only in oncology but also in the improved treatment of autoimmune disorders and infectious diseases. Finally, potential approaches to overcoming mechanisms of resistance to anti-CD20 therapy are discussed, chiefly involving the combination of anti-CD20 mAbs with various other agents to resensitize patients to treatment.

  19. Aggregation Kinetics for IgG1-Based Monoclonal Antibody Therapeutics.

    Science.gov (United States)

    Singla, A; Bansal, R; Joshi, Varsha; Rathore, Anurag S

    2016-05-01

    Monoclonal antibodies (mAbs) as a class of therapeutic molecules are finding an increasing demand in the biotechnology industry for the treatment of diseases like cancer and multiple sclerosis. A key challenge associated to successful commercialization of mAbs is that from the various physical and chemical instabilities that are inherent to these molecules. Out of all probable instabilities, aggregation of mAbs has been a major problem that has been associated with a change in the protein structure and is a hurdle in various upstream and downstream processes. It can stimulate immune response causing protein misfolding having deleterious and harmful effects inside a cell. Also, the extra cost incurred to remove aggregated mAbs from the rest of the batch is huge. Size exclusion chromatography (SEC) is a major technique for characterizing aggregation in mAbs where change in the aggregates' size over time is estimated. The current project is an attempt to understand the rate and mechanism of formation of higher order oligomers when subjected to different environmental conditions such as buffer type, temperature, pH, and salt concentration. The results will be useful in avoiding the product exposure to conditions that can induce aggregation during upstream, downstream, and storage process. Extended Lumry-Eyring model (ELE), Lumry-Eyring Native Polymerization model (LENP), and Finke-Watzky model (F-W) have been employed in this work to fit the aggregation experimental data and results are compared to find the best fit model for mAb aggregation to connect the theoretical dots with the reality.

  20. New Strategies for the Next Generation of Matrix-Metalloproteinase Inhibitors: Selectively Targeting Membrane-Anchored MMPs with Therapeutic Antibodies

    Directory of Open Access Journals (Sweden)

    Laetitia Devy

    2011-01-01

    Full Text Available MMP intervention strategies have met with limited clinical success due to severe toxicities. In particular, treatment with broad-spectrum MMP-inhibitors (MMPIs caused musculoskeletal pain and inflammation. Selectivity may be essential for realizing the clinical potential of MMPIs. Here we review discoveries pinpointing membrane-bound MMPs as mediators of mechanisms underlying cancer and inflammation and as possible therapeutic targets for prevention/treatment of these diseases. We discuss strategies to target these therapeutic proteases using highly selective inhibitory agents (i.e., human blocking antibodies against individual membrane-bound MMPs.

  1. Human antibodies to the dengue virus E-dimer epitope have therapeutic activity against Zika virus infection.

    Science.gov (United States)

    Fernandez, Estefania; Dejnirattisai, Wanwisa; Cao, Bin; Scheaffer, Suzanne M; Supasa, Piyada; Wongwiwat, Wiyada; Esakky, Prabagaran; Drury, Andrea; Mongkolsapaya, Juthathip; Moley, Kelle H; Mysorekar, Indira U; Screaton, Gavin R; Diamond, Michael S

    2017-11-01

    The Zika virus (ZIKV) epidemic has resulted in congenital abnormalities in fetuses and neonates. Although some cross-reactive dengue virus (DENV)-specific antibodies can enhance ZIKV infection in mice, those recognizing the DENV E-dimer epitope (EDE) can neutralize ZIKV infection in cell culture. We evaluated the therapeutic activity of human monoclonal antibodies to DENV EDE for their ability to control ZIKV infection in the brains, testes, placentas, and fetuses of mice. A single dose of the EDE1-B10 antibody given 3 d after ZIKV infection protected against lethality, reduced ZIKV levels in brains and testes, and preserved sperm counts. In pregnant mice, wild-type or engineered LALA variants of EDE1-B10, which cannot engage Fcg receptors, diminished ZIKV burden in maternal and fetal tissues, and protected against fetal demise. Because neutralizing antibodies to EDE have therapeutic potential against ZIKV, in addition to their established inhibitory effects against DENV, it may be possible to develop therapies that control disease caused by both viruses.

  2. A Therapeutic Antibody against West Nile Virus Neutralizes Infection by Blocking Fusion within Endosomes

    NARCIS (Netherlands)

    Thompson, Bruce S.; Moesker, Bastiaan; Smit, Jolanda M.; Wilschut, Jan; Diamond, Michael S.; Fremont, Daved H.

    Defining the precise cellular mechanisms of neutralization by potently inhibitory antibodies is important for understanding how the immune system successfully limits viral infections. We recently described a potently inhibitory monoclonal antibody (MAb E16) against the envelope (E) protein of West

  3. Therapeutic intradermal delivery of tumor necrosis factor-alpha antibodies using tip-loaded dissolvable microneedle arrays.

    Science.gov (United States)

    Korkmaz, Emrullah; Friedrich, Emily E; Ramadan, Mohamed H; Erdos, Geza; Mathers, Alicia R; Burak Ozdoganlar, O; Washburn, Newell R; Falo, Louis D

    2015-09-01

    Tumor necrosis factor-alpha (TNF-α) specific antibodies (anti-TNF-α Ab) have been shown to be potent TNF inhibitors and effective therapeutics for a range of inflammatory diseases. Typically, these drugs are administered systemically, but systemic dosing sufficient to achieve locally effective concentrations in peripheral tissues has been associated with systemic immunosuppression and related adverse events. Here, we evaluated the use of tip-loaded dissolvable microneedle arrays (MNAs) for localized intradermal delivery of anti-TNF-α Ab. MNAs with obelisk shape microneedles that incorporate the antibody cargo in the needle tips were created from carboxymethylcellulose (CMC) using a micromilling/spin-casting fabrication method. We found that anti-TNF-α Ab integrated into MNAs using this room temperature fabrication process maintained conformationally dependent TNF-α binding activity. Further, these MNAs efficiently delivered anti-TNF-α antibodies to the dermis of human skin with clinically applicable release profiles. To evaluate MNA delivered anti-TNF-α Ab function, we applied anti-TNF-α Ab containing MNAs to established psoriasiform lesions on the skin of mice. MNA anti-TNF-α Ab treatment reduced key biomarkers of psoriasiform inflammation including epidermal thickness and IL-1β expression. Taken together, these results demonstrate efficient and biologically effective MNA delivery of anti-TNF-α Ab to the intradermal microenvironment of the skin in mice and humans, and support the development of MNA mediated antibody delivery for clinical applications. Tumor necrosis factor-alpha (TNF-α) specific antibodies (anti-TNF-α Ab) have been shown to be potent TNF inhibitors and effective therapeutics for a range of inflammatory diseases. Typically, these drugs are administered systemically, but systemic dosing sufficient to achieve locally effective concentrations in peripheral tissues has been associated with systemic immunosuppression and related adverse

  4. Clinical management of multiple sclerosis and neuromyelitis optica with therapeutic monoclonal antibodies: approved therapies and emerging candidates.

    Science.gov (United States)

    Dubey, Divyanshu; Kieseier, Bernd C; Hartung, Hans Peter; Hemmer, Bernhard; Miller-Little, William A; Stuve, Olaf

    2015-01-01

    Therapeutic monoclonal antibodies (mAbs) are a relatively novel class of drugs that has substantially advanced immunotherapy for patients with multiple sclerosis. The advantage of these agents is that they bind specifically and exclusively to predetermined proteins or cells. Natalizumab was the first mAb in neurology to obtain approval. It is also considered one of the most potent options for annualized relapse rate reduction among available therapeutic options. Alemtuzumab is currently also approved in several countries. Several mAbs have been tested in clinical studies in multiple sclerosis. Here, we review the history of drug development of therapeutic mAbs and their classification. Furthermore, we outline the putative mechanisms of action, clinical evidence and safety of approved mAbs and those in different stages of clinical development in multiple sclerosis and neuromyelitis optica.

  5. CD4+ levels control the odds of induction of humoral immune responses to tracer doses of therapeutic antibodies.

    Science.gov (United States)

    Srinivasula, Sharat; Gabriel, Erin; Kim, Insook; DeGrange, Paula; St Claire, Alexis; Mallow, Candace; Donahue, Robert E; Paik, Chang; Lane, H C; Di Mascio, Michele

    2017-01-01

    Rapidly increasing number of therapeutic antibodies are being repurposed to imaging probes for noninvasive diagnosis, as well as monitoring during treatment or disease recurrence. Though antibody-based imaging involves tracer doses (~3 log lower than therapeutic doses), and immune responses are severely reduced in patients with impaired immunity, formation of anti-tracer antibodies (ATA) has been observed hampering further diagnostic monitoring. Here, we explored the potential to develop humoral responses to intravenously administered tracer dose of a monoclonal antibody F(ab΄)2 fragment, and associated with host related immune measures in 49 rhesus macaques categorized into healthy (uninfected controls), SIV-progressors, SIV non-progressors, or total body irradiated (TBI). Antibody fragment administered in tracer amount (~100μg) induced immune responses with significantly lower odds in SIV-progressors or TBI macaques (P<0.005) as compared to healthy animals. Peripheral blood (PB) CD4+ cell counts, but not CD20+ cell levels, were associated with significantly higher risk of developing a humoral response (P<0.001). Doubling the PB CD4+ counts is associated with an odds ratio of developing an immune response of 1.73. Among SIV-infected animals, CD4+ cell count was a stronger predictor of immune response than plasma SIV-RNA levels. Both SIV-progressors and TBI macaques showed higher odds of responses with increasing CD4+ counts, however when compared to healthy or SIV non-progressors with similar CD4+ count, they were still functionally incompetent in generating a response (P<0.01). Moreover, presence of ATA in systemic circulation altered the in vivo biodistribution by increasing hepatic uptake and decreasing plasma radiotracer clearance, with minimal to no binding detected in targeted tissues.

  6. Lysyl oxidase like-4 monoclonal antibody demonstrates therapeutic effect against head and neck squamous cell carcinoma cells and xenografts.

    Science.gov (United States)

    Görögh, Tibor; Quabius, Elgar S; Heidebrecht, Hans; Nagy, Andreas; Muffels, Till; Haag, Jochen; Ambrosch, Petra; Hoffmann, Markus

    2016-05-15

    A new member of the lysyl oxidase (LOX) family, lysyl oxidase-like 4 (LOXL4), is overexpressed in head and neck squamous cell carcinoma (HNSCC) compared to normal squamous epithelium. A monoclonal antibody (mAb) derived from fusion of Balb/c mouse splenocytes immunized with LOXL4 specific peptide was used to evaluate its therapeutic efficacy in 15 HNSCC cell lines associated with LOXL4 overexpression. For xenograft experiments 41 severe combined immunodeficient (SCID) mice were used to analyze LOXL4-mAb mediated tumor regression. Cell viability was analyzed using cytotoxicity-, and clonogenic-assays. Significant suppression of tumor cell growth was observed in 12 out of 15 (80%) tumor cell lines after 48 hr exposure to the mAb (LD50 of 15 µg/ml to 45 µg/ml). The effect induced by the antibody could be blocked by pre-incubation of the antibody with the peptide used for immunization of the mice and antibody generation, indicating that the effect of the antibody is specific. In mice inoculated with HNSCC cells, i.v. injections of the LOXL4-mAb resulted within 70 days in extensive tumor destruction in all treated animals whereas no tumor regression occurred in control animals. In mice pre-immunized i.v. with LOXL4-mAb and subsequently injected with HNSCC cells, tumor development was considerably delayed in contrast to non LOXL4-mAb pre-immunized animals. These results demonstrate that the LOXL4-mAb has potent antitumor activity and suggest its suitability as a therapeutic immune agent applicable to HNSCC exhibiting tumor specific upregulation of LOXL4. © 2016 UICC.

  7. Pre-Clinical Development of a Humanized Anti-CD47 Antibody with Anti-Cancer Therapeutic Potential.

    Directory of Open Access Journals (Sweden)

    Jie Liu

    Full Text Available CD47 is a widely expressed cell surface protein that functions as a regulator of phagocytosis mediated by cells of the innate immune system, such as macrophages and dendritic cells. CD47 serves as the ligand for a receptor on these innate immune cells, SIRP-alpha, which in turn delivers an inhibitory signal for phagocytosis. We previously found increased expression of CD47 on primary human acute myeloid leukemia (AML stem cells, and demonstrated that blocking monoclonal antibodies directed against CD47 enabled the phagocytosis and elimination of AML, non-Hodgkin's lymphoma (NHL, and many solid tumors in xenograft models. Here, we report the development of a humanized anti-CD47 antibody with potent efficacy and favorable toxicokinetic properties as a candidate therapeutic. A novel monoclonal anti-human CD47 antibody, 5F9, was generated, and antibody humanization was carried out by grafting its complementarity determining regions (CDRs onto a human IgG4 format. The resulting humanized 5F9 antibody (Hu5F9-G4 bound monomeric human CD47 with an 8 nM affinity. Hu5F9-G4 induced potent macrophage-mediated phagocytosis of primary human AML cells in vitro and completely eradicated human AML in vivo, leading to long-term disease-free survival of patient-derived xenografts. Moreover, Hu5F9-G4 synergized with rituximab to eliminate NHL engraftment and cure xenografted mice. Finally, toxicokinetic studies in non-human primates showed that Hu5F9-G4 could be safely administered intravenously at doses able to achieve potentially therapeutic serum levels. Thus, Hu5F9-G4 is actively being developed for and has been entered into clinical trials in patients with AML and solid tumors (ClinicalTrials.gov identifier: NCT02216409.

  8. Pre-Clinical Development of a Humanized Anti-CD47 Antibody with Anti-Cancer Therapeutic Potential.

    Science.gov (United States)

    Liu, Jie; Wang, Lijuan; Zhao, Feifei; Tseng, Serena; Narayanan, Cyndhavi; Shura, Lei; Willingham, Stephen; Howard, Maureen; Prohaska, Susan; Volkmer, Jens; Chao, Mark; Weissman, Irving L; Majeti, Ravindra

    2015-01-01

    CD47 is a widely expressed cell surface protein that functions as a regulator of phagocytosis mediated by cells of the innate immune system, such as macrophages and dendritic cells. CD47 serves as the ligand for a receptor on these innate immune cells, SIRP-alpha, which in turn delivers an inhibitory signal for phagocytosis. We previously found increased expression of CD47 on primary human acute myeloid leukemia (AML) stem cells, and demonstrated that blocking monoclonal antibodies directed against CD47 enabled the phagocytosis and elimination of AML, non-Hodgkin's lymphoma (NHL), and many solid tumors in xenograft models. Here, we report the development of a humanized anti-CD47 antibody with potent efficacy and favorable toxicokinetic properties as a candidate therapeutic. A novel monoclonal anti-human CD47 antibody, 5F9, was generated, and antibody humanization was carried out by grafting its complementarity determining regions (CDRs) onto a human IgG4 format. The resulting humanized 5F9 antibody (Hu5F9-G4) bound monomeric human CD47 with an 8 nM affinity. Hu5F9-G4 induced potent macrophage-mediated phagocytosis of primary human AML cells in vitro and completely eradicated human AML in vivo, leading to long-term disease-free survival of patient-derived xenografts. Moreover, Hu5F9-G4 synergized with rituximab to eliminate NHL engraftment and cure xenografted mice. Finally, toxicokinetic studies in non-human primates showed that Hu5F9-G4 could be safely administered intravenously at doses able to achieve potentially therapeutic serum levels. Thus, Hu5F9-G4 is actively being developed for and has been entered into clinical trials in patients with AML and solid tumors (ClinicalTrials.gov identifier: NCT02216409).

  9. Development and characterization of a pre-treatment procedure to eliminate human monoclonal antibody therapeutic drug and matrix interference in cell-based functional neutralizing antibody assays.

    Science.gov (United States)

    Xu, Weifeng; Jiang, Hao; Titsch, Craig; Haulenbeek, Jonathan R; Pillutla, Renuka C; Aubry, Anne-Françoise; DeSilva, Binodh S; Arnold, Mark E; Zeng, Jianing; Dodge, Robert W

    2015-01-01

    Biological therapeutics can induce an undesirable immune response resulting in the formation of anti-drug antibodies (ADA), including neutralizing antibodies (NAbs). Functional (usually cell-based) NAb assays are preferred to determine NAb presence in patient serum, but are often subject to interferences from numerous serum factors, such as growth factors and disease-related cytokines. Many functional cell-based NAb assays are essentially drug concentration assays that imply the presence of NAbs by the detection of small changes in functional drug concentration. Any drug contained in the test sample will increase the total amount of drug in the assay, thus reducing the sensitivity of NAb detection. Biotin-drug Extraction with Acid Dissociation (BEAD) has been successfully applied to extract ADA, thereby removing drug and other interfering factors from human serum samples. However, to date there has been no report to estimate the residual drug level after BEAD treatment when the drug itself is a human monoclonal antibody; mainly due to the limitation of traditional ligand-binding assays. Here we describe a universal BEAD optimization procedure for human monoclonal antibody (mAb) drugs by using a LC-MS/MS method to simultaneously measure drug (a mutant human IgG4), NAb positive control (a mouse IgG), and endogenous human IgGs as an indicator of nonspecific carry-over in the BEAD eluate. This is the first report demonstrating that residual human mAb drug level in clinical sample can be measured after BEAD pre-treatment, which is critical for further BEAD procedure optimization and downstream immunogenicity testing. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Therapeutic Anti-Methamphetamine Antibody Fragment-Nanoparticle Conjugates: Synthesis and In Vitro Characterization

    OpenAIRE

    Nanaware-Kharade, Nisha; Gonzalez, Guillermo A.; Lay, Jackson O.; Hendrickson, Howard P.; Peterson, Eric C.

    2012-01-01

    Treatments specific to the medical problems caused by methamphetamine (METH) abuse are greatly needed. Towards this goal, we are developing new multivalent anti-METH antibody fragment-nanoparticle conjugates with customizable pharmacokinetic properties. We have designed a novel anti-METH single chain antibody fragment with an engineered terminal cysteine (scFv6H4Cys). Generation 3 (G3) polyamidoamine dendrimer nanoparticles were chosen for conjugation due to their monodisperse properties and ...

  11. A generic sample preparation approach for LC–MS/MS bioanalysis of therapeutic monoclonal antibodies in serum applied to Infliximab

    Directory of Open Access Journals (Sweden)

    Anne J. Kleinnijenhuis

    2015-01-01

    Full Text Available In this study, we developed a generic bioanalytical workflow providing sensitive, specific, and accurate absolute quantification of therapeutic monoclonal antibodies in serum. The workflow involves magnetic beads coated with protein A to pull-down therapeutic monoclonal antibodies with affinity for protein A from the biological matrix, followed by tryptic digestion and LC-MS/MS quantification of a unique signature peptide, considering of course the matrix of interest and other present mAbs, if applicable. The feasibility of this approach was demonstrated for Infliximab (trade name Remicade in rat serum. The assigned signature peptide was monitored in the selected reaction monitoring (SRM mode. Assay variability was determined to be below 20%, except at the QC low level, which was provided through optimization of the sample preparation and monitoring of the LC-MS/MS using a stable isotope labeled signature peptide as internal standard. The 100 ng/ml lower limit of quantification using only 25 μl sample volume, is generally considered as sufficient for pharmaceutical development purposes for monoclonal antibodies.

  12. In vivo imaging using fluorescent antibodies to tumor necrosis factor predicts therapeutic response in Crohn’s disease

    Science.gov (United States)

    Atreya, Raja; Neumann, Helmut; Neufert, Clemens; Waldner, Maximilian J; Billmeier, Ulrike; Zopf, Yurdagül; Willma, Marcus; App, Christine; Münster, Tino; Kessler, Hermann; Maas, Stefanie; Gebhardt, Bernd; Heimke-Brinck, Ralph; Reuter, Eva; Dörje, Frank; Rau, Tilman T; Uter, Wolfgang; Wang, Thomas D; Kiesslich, Ralf; Vieth, Michael; Hannappel, Ewald; Neurath, Markus F

    2015-01-01

    As antibodies to tumor necrosis factor (TNF) suppress immune responses in Crohn’s disease by binding to membrane-bound TNF (mTNF), we created a fluorescent antibody for molecular mTNF imaging in this disease. Topical antibody administration in 25 patients with Crohn’s disease led to detection of intestinal mTNF+ immune cells during confocal laser endomicroscopy. Patients with high numbers of mTNF+ cells showed significantly higher short-term response rates (92%) at week 12 upon subsequent anti-TNF therapy as compared to patients with low amounts of mTNF+ cells (15%). This clinical response in the former patients was sustained over a follow-up period of 1 year and was associated with mucosal healing observed in follow-up endoscopy. These data indicate that molecular imaging with fluorescent antibodies has the potential to predict therapeutic responses to biological treatment and can be used for personalized medicine in Crohn’s disease and autoimmune or inflammatory disorders. PMID:24562382

  13. Rational Design of Dual Agonist-Antibody Fusions as Long-acting Therapeutic Hormones.

    Science.gov (United States)

    Liu, Yan; Wang, Ying; Zhang, Yong; Liu, Tao; Jia, Haiqun; Zou, Huafei; Fu, Qiangwei; Zhang, Yuhan; Lu, Lucy; Chao, Elizabeth; Parker, Holly; Nguyen-Tran, Van; Shen, Weijun; Wang, Danling; Schultz, Peter G; Wang, Feng

    2016-11-18

    Recent studies have suggested that modulation of two or more signaling pathways can achieve substantial weight loss and glycemic stability. We have developed an approach to the generation of bifunctional antibody agonists that activate leptin receptor and GLP-1 receptor. Leptin was fused into the complementarity determining region 3 loop of the light chain alone, or in combination with exendin-4 (EX4) fused at the N-terminus of the heavy chain of Herceptin. The antibody fusions exhibit similar or increased in vitro activities on their cognate receptors, but 50-100-fold longer circulating half-lives in rodents compared to the corresponding native peptides/proteins. The efficacy of the leptin/EX4 dual antibody fusion on weight loss, especially fat mass loss, was enhanced in ob/ob mice and DIO mice compared to the antibody fusion of either EX4 or leptin alone. This work demonstrates the versatility of this combinatorial fusion strategy for generating dual antibody agonists with long half-lives.

  14. Utility of the P19 suppressor of gene-silencing protein for production of therapeutic antibodies in Nicotiana expression hosts.

    Science.gov (United States)

    Garabagi, Freydoun; Gilbert, Erin; Loos, Andreas; McLean, Michael D; Hall, J Christopher

    2012-12-01

    To study how the P19 suppressor of gene-silencing protein can be used effectively for the production of therapeutic glycoproteins, the following factors were examined: the genetic elements used for expressing recombinant proteins; the effect of different P19 concentrations; compatibility of P19 with various Nicotiana tabacum cultivars for transgenic expression; the glycan profile of a recombinant therapeutic glycoprotein co-expressed with P19 in an RNAi-based glycomodified Nicotiana benthamiana expression host. The coding sequences for the heavy and light chains of trastuzumab were cloned into five plant expression vectors (102-106) containing different 5' and 3' UTRs, designated as vector sets 102-106 mAb. The P19 protein of Tomato bushy stunt virus (TBSV) was also cloned into vector 103, which contained the Cauliflower mosaic virus (CaMV) 35S promoter and 5'UTR together with the terminator region of the nopaline synthase gene of Agrobacterium. Transient expression of the antibody vectors resulted in different levels of trastuzumab accumulation, the highest being 105 and 106 mAb at about 1% of TSP. P19 increased the concentration of trastuzumab approximately 15-fold (to about 2.3% of TSP) when co-expressed with 103 mAb but did not affect antibody levels with vectors 102 and 106 mAb. When 103 mAb was expressed together with P19 in different N. tabacum cultivars, all except Little Crittenden showed a marked discolouring of the infiltrated areas of the leaf and decreased antibody expression. Co-expression of P19 also abolished antibody accumulation in crosses between N. tabacum cv. I-64 and Little Crittenden, indicating a dominant mode of inheritance for the observed P19-induced responses. © 2012 The Authors Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  15. Selection of therapeutic H5N1 monoclonal antibodies following IgVH repertoire analysis in mice.

    Science.gov (United States)

    Gray, Sean A; Moore, Margaret; VandenEkart, Emily J; Roque, Richard P; Bowen, Richard A; Van Hoeven, Neal; Wiley, Steven R; Clegg, Christopher H

    2016-07-01

    The rapid rate of influenza virus mutation drives the emergence of new strains that inflict serious seasonal epidemics and less frequent, but more deadly, pandemics. While vaccination provides the best protection against influenza, its utility is often diminished by the unpredictability of new pathogenic strains. Consequently, efforts are underway to identify new antiviral drugs and monoclonal antibodies that can be used to treat recently infected individuals and prevent disease in vulnerable populations. Next Generation Sequencing (NGS) and the analysis of antibody gene repertoires is a valuable tool for Ab discovery. Here, we describe a technology platform for isolating therapeutic monoclonal antibodies (MAbs) by analyzing the IgVH repertoires of mice immunized with recombinant H5N1 hemagglutinin (rH5). As an initial proof of concept, 35 IgVH genes were selected using a CDRH3 search algorithm and co-expressed in a murine IgG2a expression vector with a panel of germline murine kappa genes. Culture supernatants were then screened for antigen binding. Seventeen of the 35 IgVH MAbs (49%) bound rH5VN1203 in preliminary screens and 8 of 9 purified MAbs inhibited 3 heterosubtypic strains of H5N1 virus when assayed by HI. Two of these MAbs demonstrated prophylactic and therapeutic activity in virus-challenged mice. This is the first example in which an NGS discovery platform has been used to isolate anti-influenza MAbs with relevant therapeutic activity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Therapeutic Effectiveness of Anti-RAGE Antibody Administration in a Rat Model of Crush Injury.

    Science.gov (United States)

    Matsumoto, Hisatake; Matsumoto, Naoya; Shimazaki, Junya; Nakagawa, Junichiro; Imamura, Yukio; Yamakawa, Kazuma; Yamada, Tomoki; Ikeda, Mitsunori; Hiraike, Hiroko; Ogura, Hiroshi; Shimazu, Takeshi

    2017-09-25

    Crush injury patients often have systemic inflammatory response syndrome that leads to multiple organ failure. Receptor for advanced glycation endproducts (RAGE) functions as a pattern recognition receptor that regulates inflammation. We evaluated the effects of anti-RAGE antibody in a crush injury model. Pressure was applied to both hindlimbs of rats for 6 h by 3.0-kg blocks and then released. Animals were randomly divided into the sham (RAGE-Sh) group, crush (RAGE-Ctrl) group or anti-RAGE antibody-treated crush (RAGE-Tx) group. Samples were collected at 3, 6 and 24 h after releasing pressure. In the RAGE-Ctrl group, fluorescent immunostaining in the lung showed upregulated RAGE expression at 3 h. The serum soluble RAGE (sRAGE) level, which reflects the amount of RAGE expression in systemic tissue, increased at 6 h. Serum interleukin 6 (IL-6; systemic inflammation marker) increased immediately at 3 h. Histological analysis revealed lung injury at 6 and 24 h. Administration of anti-RAGE antibody before releasing compression inhibited upregulated RAGE expression in the lung alveoli, suppressed RAGE-associated mediators sRAGE and IL6, attenuated the lung damage and improved the 7-day survival rate. Collectively, our results indicated that the use of anti-RAGE antibody before releasing compression is associated with a favourable prognosis following crush injury.

  17. Drug: D09207 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ecularly targeted agents Monoclonal antibody Catumaxomab [ATC:L01XC09] D09207 Catumaxomab (INN) CAS: 509077-98-9 PubChem: 96025887 ... ...r CD3 [HSA:915 916 917] [KO:K06450 K06451 K06452] Catumaxomab [ATC:L01XC09] D09207 Catumaxomab (INN) Antineoplastics [BR:br08308] Mol

  18. Therapeutic administration of a recombinant human monoclonal antibody reduces the severity of chikungunya virus disease in rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Rebecca Broeckel

    2017-06-01

    Full Text Available Chikungunya virus (CHIKV is a mosquito-borne virus that causes a febrile syndrome in humans associated with acute and chronic debilitating joint and muscle pain. Currently no licensed vaccines or therapeutics are available to prevent or treat CHIKV infections. We recently isolated a panel of potently neutralizing human monoclonal antibodies (mAbs, one (4N12 of which exhibited prophylactic and post-exposure therapeutic activity against CHIKV in immunocompromised mice. Here, we describe the development of an engineered CHIKV mAb, designated SVIR001, that has similar antigen binding and neutralization profiles to its parent, 4N12. Because therapeutic administration of SVIR001 in immunocompetent mice significantly reduced viral load in joint tissues, we evaluated its efficacy in a rhesus macaque model of CHIKV infection. Rhesus macaques that were treated after infection with SVIR001 showed rapid elimination of viremia and less severe joint infiltration and disease compared to animals treated with SVIR002, an isotype control mAb. SVIR001 reduced viral burden at the site of infection and at distant sites and also diminished the numbers of activated innate immune cells and levels of pro-inflammatory cytokines and chemokines. SVIR001 therapy; however, did not substantively reduce the induction of CHIKV-specific B or T cell responses. Collectively, these results show promising therapeutic activity of a human anti-CHIKV mAb in rhesus macaques and provide proof-of-principle for its possible use in humans to treat active CHIKV infections.

  19. Anti-MMP-9 Antibody: A Promising Therapeutic Strategy for Treatment of Inflammatory Bowel Disease Complications with Fibrosis.

    Science.gov (United States)

    Goffin, Laurence; Fagagnini, Stefania; Vicari, Alain; Mamie, Céline; Melhem, Hassan; Weder, Bruce; Lutz, Christian; Lang, Silvia; Scharl, Michael; Rogler, Gerhard; Chvatchko, Yolande; Hausmann, Martin

    2016-09-01

    Despite medical treatments or surgical options, more than one-third of patients with Crohn's disease suffer from recurring fistulae. Matrix metalloprotease 9 (MMP-9), a type IV collagenase that cleaves components of the extracellular matrix leading to tissue remodeling, is upregulated in crypt abscesses and around fistulae suggesting an important role for this enzyme in fistula formation. Our aims were (1) to correlate serum levels of MMP-9 degradation products in patients with CD with the presence of fistulae and (2) to investigate the impact of selective MMP-9 inhibition in a mouse model of intestinal fibrosis. Serum MMP-9 degradation products were quantified in subjects affected with nonstricturing and nonpenetrating CD (n = 50), stricturing CD (n = 41), penetrating CD (n = 22), CD with perianal fistula (n = 29), and healthy controls (n = 10). Therapeutic efficacy of anti-MMP-9 monoclonal antibodies was assessed in a heterotopic xenograft model of intestinal fibrosis. C3M, an MMP-9 degradation product of collagen III, demonstrated the highest serum levels in patients with penetrating CD and differentiated penetrating CD from other CD subgroups and healthy controls, P = 0.0005. Anti-MMP-9 treatments reduced collagen deposition and hydroxyproline content in day-14 intestinal grafts indicating reduced fibrosis. The serologic biomarker C3M can discriminate penetrating CD from other CD subgroups and could serve as marker for the development of penetrating CD. Anti-MMP-9 antibody has therapeutic potential to prevent intestinal fibrosis in CD complications.

  20. Therapeutically targeting glypican-2 via single-domain antibody-based chimeric antigen receptors and immunotoxins in neuroblastoma.

    Science.gov (United States)

    Li, Nan; Fu, Haiying; Hewitt, Stephen M; Dimitrov, Dimiter S; Ho, Mitchell

    2017-08-08

    Neuroblastoma is a childhood cancer that is fatal in almost half of patients despite intense multimodality treatment. This cancer is derived from neuroendocrine tissue located in the sympathetic nervous system. Glypican-2 (GPC2) is a cell surface heparan sulfate proteoglycan that is important for neuronal cell adhesion and neurite outgrowth. In this study, we find that GPC2 protein is highly expressed in about half of neuroblastoma cases and that high GPC2 expression correlates with poor overall survival compared with patients with low GPC2 expression. We demonstrate that silencing of GPC2 by CRISPR-Cas9 or siRNA results in the inhibition of neuroblastoma tumor cell growth. GPC2 silencing inactivates Wnt/β-catenin signaling and reduces the expression of the target gene N-Myc, an oncogenic driver of neuroblastoma tumorigenesis. We have isolated human single-domain antibodies specific for GPC2 by phage display technology and found that the single-domain antibodies can inhibit active β-catenin signaling by disrupting the interaction of GPC2 and Wnt3a. To explore GPC2 as a potential target in neuroblastoma, we have developed two forms of antibody therapeutics, immunotoxins and chimeric antigen receptor (CAR) T cells. Immunotoxin treatment was demonstrated to inhibit neuroblastoma growth in mice. CAR T cells targeting GPC2 eliminated tumors in a disseminated neuroblastoma mouse model where tumor metastasis had spread to multiple clinically relevant sites, including spine, skull, legs, and pelvis. This study suggests GPC2 as a promising therapeutic target in neuroblastoma.

  1. Therapeutic potential and challenges of targeting receptor tyrosine kinase ROR1 with monoclonal antibodies in B-cell malignancies.

    Directory of Open Access Journals (Sweden)

    Jiahui Yang

    Full Text Available Based on its selective cell surface expression in chronic lymphocytic leukemia (CLL and mantle cell lymphoma (MCL, receptor tyrosine kinase ROR1 has recently emerged as a promising target for therapeutic monoclonal antibodies (mAbs. To further assess the suitability of ROR1 for targeted therapy of CLL and MCL, a panel of mAbs was generated and its therapeutic utility was investigated.A chimeric rabbit/human Fab library was generated from immunized rabbits and selected by phage display. Chimeric rabbit/human Fab and IgG1 were investigated for their capability to bind to human and mouse ROR1, to mediate antibody-dependent cellular cytotoxicity (ADCC, complement-dependent cytotoxicity (CDC, and internalization, and to agonize or antagonize apoptosis using primary CLL cells from untreated patients as well as MCL cell lines. A panel of mAbs demonstrated high affinity and specificity for a diverse set of epitopes that involve all three extracellular domains of ROR1, are accessible on the cell surface, and mediate internalization. The mAb with the highest affinity and slowest rate of internalization was found to be the only mAb that mediated significant, albeit weak, ADCC. None of the mAbs mediated CDC. Alone, they did not enhance or inhibit apoptosis.Owing to its relatively low cell surface density, ROR1 may be a preferred target for armed rather than naked mAbs. Provided is a panel of fully sequenced and thoroughly characterized anti-ROR1 mAbs suitable for conversion to antibody-drug conjugates, immunotoxins, chimeric antigen receptors, and other armed mAb entities for preclinical and clinical studies.

  2. Intracellular trafficking of new anticancer therapeutics: antibody–drug conjugates

    OpenAIRE

    Kalim M; Chen J.; Wang S.; Lin C.; Ullah S; Liang K; Ding Q; Chen S; Zhan JB

    2017-01-01

    Muhammad Kalim,1 Jie Chen,1 Shenghao Wang,1 Caiyao Lin,1 Saif Ullah,1 Keying Liang,1 Qian Ding,1 Shuqing Chen,2 Jinbiao Zhan1 1Department of Biochemistry and Genetics, School of Medicine, 2Department of Pharmaceutical Analysis, College of Pharmaceutical Science, Zhejiang University, Hangzhou, People’s Republic of China Abstract: Antibody–drug conjugate (ADC) is a milestone in targeted cancer therapy that comprises of monoclonal antibodies chemically linked to cytotoxic d...

  3. The value of non-human primates in the development of therapeutic monoclonal antibodies

    NARCIS (Netherlands)

    Van Meer, P.J.K.|info:eu-repo/dai/nl/34153790X; Kooijman, M.|info:eu-repo/dai/nl/322905788; Van Der Laan, J.W.|info:eu-repo/dai/nl/374879966; Moors, E.H.M.|info:eu-repo/dai/nl/20241664X; Schellekens, H.|info:eu-repo/dai/nl/068406762

    2011-01-01

    The pharmaceutical industry is increasingly focusing on the development of biological therapeutics. These molecules generally cause no off-target toxicity and are highly species specific. Therefore, non-human primates (NHPs) are often the only relevant species in which to conduct regulatory safety

  4. Bulky Polar Additives That Greatly Reduce the Viscosity of Concentrated Solutions of Therapeutic Monoclonal Antibodies.

    Science.gov (United States)

    Larson, Alyssa M; Weight, Alisha K; Love, Kevin; Bonificio, Amanda; Wescott, Charles R; Klibanov, Alexander M

    2017-05-01

    The viscosity of concentrated aqueous solutions of 3 clinical monoclonal antibodies (mAbs), Erbitux®, Herceptin®, and Rituxan®, has been reduced up to over 10-fold by adding certain bulky polar additives instead of saline at isotonic levels. Because these additives are also found not to compromise mAbs' stability against aggregation induced by stresses, a drug-delivery modality switch from intravenous infusions to more convenient and inexpensive parenteral options like subcutaneous injections may become possible. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  5. Therapeutic antitumor efficacy of monoclonal antibody against Claudin-4 for pancreatic and ovarian cancers.

    Science.gov (United States)

    Suzuki, Masayo; Kato-Nakano, Mariko; Kawamoto, Shinobu; Furuya, Akiko; Abe, Yuzuru; Misaka, Hirofumi; Kimoto, Naoya; Nakamura, Kazuyasu; Ohta, So; Ando, Hiroshi

    2009-09-01

    Claudin-4 (CLDN4) is a tetraspanin transmembrane protein of tight junction structure and is highly expressed in pancreatic and ovarian cancers. In this study, we aimed to generate an anti-Claudin-4 monoclonal antibody (mAb) and evaluate its antitumor efficacy in vitro and in vivo. To isolate specific mAb, we generated CLDN3, 4, 5, 6, and 9, expressing Chinese hamster ovary (CHO) cells, and then used them as positive and negative targets through cell-based screening. As a result, we succeeded in isolating KM3900 (IgG2a), which specifically bound to CLDN4, from BXSB mice immunized with pancreatic cancer cells. Immunoprecipitation and flow cytometry analysis revealed that KM3900 recognized the conformational structure and bound to extracellular loop 2 of CLDN4. Furthermore, binding of KM3900 was detected on CLDN4-expressing pancreatic and ovarian cancer cells, but not on negative cells. Next, we made the mouse-human chimeric IgG1 (KM3934) and evaluated its antitumor efficacy. KM3934 induced dose-dependent antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity in vitro, and significantly inhibited tumor growth in MCAS or CFPAC-1 xenograft SCID mice in vivo (P < 0.05). These results suggest that mAb therapy against CLDN4 is promising for pancreatic and ovarian cancers.

  6. Expression and characterization of a therapeutic monoclonal antibody in mammalian cells

    OpenAIRE

    Costa, A. R. [UNESP

    2013-01-01

    Doctoral dissertation for PhD degree in Biomedical Engineering The advent of therapeutic recombinant proteins has revolutionized modern medicine. Since the approval of recombinant insulin in 1982 to treat diabetes, many other recombinant proteins have emerged for a diversity of previously incurable conditions. In these years, the manufacturing processes have greatly evolved, but have also often disregarded product quality, an issue only recently addressed and currently a maj...

  7. Therapeutic anti-methamphetamine antibody fragment-nanoparticle conjugates: synthesis and in vitro characterization.

    Science.gov (United States)

    Nanaware-Kharade, Nisha; Gonzalez, Guillermo A; Lay, Jackson O; Hendrickson, Howard P; Peterson, Eric C

    2012-09-19

    Treatments specific to the medical problems caused by methamphetamine (METH) abuse are greatly needed. Toward this goal, we are developing new multivalent anti-METH antibody fragment-nanoparticle conjugates with customizable pharmacokinetic properties. We have designed a novel anti-METH single chain antibody fragment with an engineered terminal cysteine (scFv6H4Cys). Generation 3 (G3) polyamidoamine dendrimer nanoparticles were chosen for conjugation due to their monodisperse properties and multiple amine functional groups. ScFv6H4Cys was conjugated to G3 dendrimers via a heterobifunctional PEG cross-linker that is reactive to a free amine on one end and a thiol group on the other. PEG modified dendrimers were synthesized by reacting the PEG cross-linker with dendrimers in a stoichiometric ratio of 11:1, which were further reacted with 3-fold molar excess of anti-METH scFv6H4Cys. This reaction resulted in a heterogeneous mix of G3-PEG-scFv6H4Cys conjugates (dendribodies) with three to six scFv6H4Cys conjugated to each dendrimer. The dendribodies were separated from the unreacted PEG modified dendrimers and scFv6H4Cys using affinity chromatography. A detailed in vitro characterization of the PEG modified dendrimers and the dendribodies was performed to determine size, purity, and METH binding function. The dendribodies were found to have affinity for METH identical to that of the unconjugated scFv6H4Cys in saturation binding assays, whereas the PEG modified dendrimers had no affinity for METH. These data suggest that an anti-METH scFv can be successfully conjugated to a PEG modified dendrimer nanoparticle with no adverse effects on METH binding properties. This study is a critical step toward preclinical characterization and development of a novel nanomedicine for the treatment of METH abuse.

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

    Science.gov (United States)

    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. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Therapeutic monoclonal antibodies: scFv patents as a marker of a new class of potential biopharmaceuticals

    Directory of Open Access Journals (Sweden)

    Manuela Berto Pucca

    2011-03-01

    Full Text Available Monoclonal antibodies represent the fastest growing class of biopharmaceutical products and have a host of applications in medical research, diagnosis, therapy, and basic science. The production of recombinant monoclonal antibodies has revolutionized the generation of immunoglobulins, and their use represents a strategic breakthrough, affecting the global pharmaceutical market for therapeutic proteins. In the present work, a review of scFv, and the number of related patents, has been carried out. The results show that several countries have scFv patents, most notably the United States, China and United Kingdom. The target of these scFv antibodies was also assessed and the results demonstrate that most are directed toward cancer therapy.Anticorpos monoclonais representam a classe de maior crescimento em produtos de biofármacos e possuem várias aplicações em pesquisa médica, diagnóstico, terapias e ciência básica. A produção de anticorpos monoclonais recombinantes revolucionou a geração de imunoglobulinas e sua utilização implica em avanço estratégico, afetando o mercado farmacêutico global de proteínas terapêuticas. No presente trabalho, uma revisão sobre scFv e a relação do seu número de patentes foi analisada. Os resultados mostram que vários países apresentam patentes de scFv com destaque para os Estados Unidos, China e Reino Unido. Os alvos desses anticorpos também foram avaliados e as análises revelaram que a maioria é destinado a terapias contra o câncer.

  10. Therapeutic Activity of Agonistic, Human Anti-CD40 Monoclonal Antibodies Requires Selective FcγR Engagement.

    Science.gov (United States)

    Dahan, Rony; Barnhart, Bryan C; Li, Fubin; Yamniuk, Aaron P; Korman, Alan J; Ravetch, Jeffrey V

    2016-06-13

    While engagement of the inhibitory Fcγ-receptor (FcγR) IIB is an absolute requirement for in vivo antitumor activity of agonistic mouse anti-CD40 monoclonal antibodies (mAbs), a similar requirement for human mAbs has been disputed. By using a mouse model humanized for its FcγRs and CD40, we revealed that FcγRIIB engagement is essential for the activity of human CD40 mAbs, while engagement of the activating FcγRIIA inhibits this activity. By engineering Fc variants with selective enhanced binding to FcγRIIB, but not to FcγRIIA, significantly improved antitumor immunity was observed. These findings highlight the necessity of optimizing the Fc domain for this class of therapeutic antibodies by using appropriate preclinical models that accurately reflect the unique affinities and cellular expression of human FcγR. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Guardians at the gate: Biosimilar and patent reform legislation could fundamentally change the guards for therapeutic monoclonal antibodies--Part 2.

    Science.gov (United States)

    McCabe, Kevin W

    2009-01-01

    Patent protection and FDA exclusivities are the two principal forms of protection available to companies that develop therapeutic monoclonal antibodies. Propo-sed changes to both forms of protection are currently being debated in the United States Congress. Specifically, Congress is presently debating both biosimilar and patent reform legislations. Although no bill has yet passed, it is expected that patent reform legislation should pass this year. It is less likely that a biosimilar bill will pass this year. However, when legislations are enacted, the changes will significantly impact the business of therapeutic monoclonal antibodies.

  12. A Novel Platform for the Potentiation of Therapeutic Antibodies Based on Antigen-Dependent Formation of IgG Hexamers at the Cell Surface

    DEFF Research Database (Denmark)

    de Jong, R. N.; Beurskens, F. J.; Verploegen, S.

    2016-01-01

    ) for therapeutic antibody potentiation. We identified mutations that enhanced hexamer formation and complement activation by IgG1 antibodies against a range of targets on cells from hematological and solid tumor indications. IgG1 backbones with preferred mutations E345K or E430G conveyed a strong ability to induce...... conditional complement-dependent cytotoxicity (CDC) of cell lines and chronic lymphocytic leukemia (CLL) patient tumor cells, while retaining regular pharmacokinetics and biopharmaceutical developability. Both mutations potently enhanced CDC- and antibody-dependent cellular cytotoxicity (ADCC) of a type II CD...

  13. Quantitative structural characterization of local N-glycan microheterogeneity in therapeutic antibodies by energy-resolved oxonium ion monitoring.

    Science.gov (United States)

    Toyama, Atsuhiko; Nakagawa, Hidewaki; Matsuda, Koichi; Sato, Taka-Aki; Nakamura, Yusuke; Ueda, Koji

    2012-11-20

    Site-specific characterization of glycoform heterogeneity currently requires glycan structure assignment and glycopeptide quantification in two independent experiments. We present here a new method combining multiple reaction monitoring mass spectrometry with energy-resolved structural analysis, which we termed "energy-resolved oxonium ion monitoring". We demonstrated that monitoring the yields of oligosaccharide-derived fragment ions (oxonium ions) over a wide range of collision induced dissociation (CID) energy applied to a glycopeptide precursor exhibits a glycan structure-unique fragmentation pattern. In the analysis of purified immunoglobulin glycopeptides, the energy-resolved oxonium ion profile was shown to clearly distinguish between isomeric glycopeptides. Moreover, limit of detection (LOD) of glycopeptide detection was 30 attomole injection, and quantitative dynamic range spanned 4 orders magnitude. Therefore, both quantification of glycopeptides and assignment of their glycan structures were achieved by a simple analysis procedure. We assessed the utility of this method for characterizing site-specific N-glycan microheterogeneity on therapeutic antibodies, including validation of lot-to-lot glycoform variability. A significant change in the degree of terminal galactosylation was observed in different production lots of trastuzumab and bevacizumab. Cetuximab Fab glycosylation, previously known to cause anaphylaxis, was also analyzed, and several causative antigens including Lewis X motifs were quantitatively detected. The data suggests that energy-resolved oxonium ion monitoring could fulfill the regulatory requirement on the routine quality control analysis of forthcoming biosimilar therapeutics.

  14. Amino acid interaction networks provide a new lens for therapeutic antibody discovery and anti-viral drug optimization.

    Science.gov (United States)

    Viswanathan, Karthik; Shriver, Zachary; Babcock, Gregory J

    2015-04-01

    Identification of epitopes on viral proteins for the design/identification of broadly-neutralizing monoclonal antibodies (bnAbs) or specific immunogens for vaccine development is hampered by target amino acid diversity. Recently, bnAbs have been isolated for variable viruses by screening B cells from infected individuals for neutralization breadth. Epitope mapping and structural analysis of bnAbs revealed, while some of these bnAbs target glycan moieties, most target protein regions that are conserved in sequence and/or structure. However, almost universally viruses develop mutations that allow escape from neutralization suggesting protein function may not be dependent on the observed conservation. An alternative method for identification of conserved amino acid sequences utilizes an amino acid network-based approach. Calculation of a significant interaction network (SIN) score allows for selection of amino acids that are conserved and constrained within the protein system. Amino acids with high SIN scores are predicted to mutate at lower frequency due to the impact mutation has on the structure/function of a protein. By ascertaining regions of high SIN score, therapeutics can be appropriately designed to target these regions of low mutability. Further, the use of atomic interaction networks to examine protein structure and protein-protein interfaces can complement existing structure-based computational approaches for therapeutic engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Designed Amino Acid Feed in Improvement of Production and Quality Targets of a Therapeutic Monoclonal Antibody.

    Directory of Open Access Journals (Sweden)

    Fatemeh Torkashvand

    Full Text Available Cell culture feeds optimization is a critical step in process development of pharmaceutical recombinant protein production. Amino acids are the basic supplements of mammalian cell culture feeds with known effect on their growth promotion and productivity. In this study, we reported the implementation of the Plackett-Burman (PB multifactorial design to screen the effects of amino acids on the growth promotion and productivity of a Chinese hamster ovary DG-44 (CHO-DG44 cell line producing bevacizumab. After this screening, the amino acid combinations were optimized by the response surface methodology (RSM to determine the most effective concentration in feeds. Through this strategy, the final monoclonal antibody (mAb titre was enhanced by 70%, compared to the control group. For this particular cell line, aspartic acid, glutamic acid, arginine and glycine had the highest positive effects on the final mAb titre. Simultaneously, the impact of the designed amino acid feed on some critical quality attributes of bevacizumab was examined in the group with highest productivity. The product was analysed for N-glycan profiles, charge variant distribution, and low molecular weight forms. The results showed that the target product quality has been improved using this feeding strategy. It was shown how this strategy could significantly diminish the time and number of experiments in identifying the most effective amino acids and related concentrations in target product enhancement. This model could be successfully applied to other components of culture media and feeds.

  16. Medulloblastoma: evaluation of proliferative index by monoclonal antibody Mib-1, its prognostic correlation and therapeutic implications

    Directory of Open Access Journals (Sweden)

    Ferrari Antonio Fernandes

    2003-01-01

    Full Text Available In the past few years, the monoclonal antibody MIB-1 has been used by researchers in order to retrospectively study paraffin imbibed tumor fragments. The medulloblastoma is the most common malignant central nervous system tumor in childhood. The objectives were: determination of the mean Mib-1 LI value from these patients, as well as the prognostic value of the method.This retrospective study represents an analysis of the cellular proliferation index of posterior fossa medulloblastomas collected from 22 patients at A.C. Camargo Hospital, from January 1990 to December 1999. The histopathological diagnosis was confirmed by H&E and proliferative index (LI was achived with Mib-1 which detects proliferating cells during G1, G2, S and M phases.The results demostrated that the mean Mib-1 was 30,1%, and ranged from 5,2% to 62,0%.In conclusion, this method has prognostic value, has to be used as routine for patients harboring medulloblastomas and the ones who have PI greater than the mean value found in this study, should be treated aggressively.

  17. Generation and analysis of novel plant-derived antibody-based therapeutic molecules against West Nile virus.

    Directory of Open Access Journals (Sweden)

    Junyun He

    Full Text Available Previously, our group engineered a plant-derived monoclonal antibody (MAb (pHu-E16 that efficiently treated West Nile virus (WNV infection in mice. In this study, we developed several pHu-E16 variants to improve its efficacy. These variants included a single-chain variable fragment (scFv of pHu-E16 fused to the heavy chain (HC constant domains (CH(1-3 of human IgG (pHu-E16scFv-CH(1-3 and a tetravalent molecule (Tetra pHu-E16 assembled from pHu-E16scFv-CH(1-3 with a second pHu-E16scFv fused to the light chain (LC constant region. pHu-E16scFv-CH(1-3 and Tetra pHu-E16 were efficiently expressed and assembled in plants. To assess the impact of differences in N-linked glycosylation on pHu-E16 variant assembly and function, we expressed additional pHu-E16 variants with various combinations of HC and LC components. Our study revealed that proper pairing of HC and LC was essential for the complete N-glycan processing of antibodies in both plant and animal cells. Associated with their distinct N-glycoforms, pHu-E16, pHu-E16scFv-CH(1-3 and Tetra pHu-E16 exhibited differential binding to C1q and specific Fcγ receptors (FcγR. Notably, none of the plant-derived Hu-E16 variants showed antibody-dependent enhancement (ADE activity in CD32A+ human cells, suggesting the potential of plant-produced antibodies to minimize the adverse effect of ADE. Importantly, all plant-derived MAb variants exhibited at least equivalent in vitro neutralization and in vivo protection in mice compared to mammalian cell-produced Hu-E16. This study demonstrates the capacity of plants to express and assemble a large, complex and functional IgG-like tetravalent mAb variant and also provides insight into the relationship between MAb N-glycosylation, FcγR and C1q binding, and ADE. These new insights may allow the development of safer and cost effective MAb-based therapeutics for flaviviruses, and possibly other pathogens.

  18. Generation and analysis of novel plant-derived antibody-based therapeutic molecules against West Nile virus.

    Science.gov (United States)

    He, Junyun; Lai, Huafang; Engle, Michael; Gorlatov, Sergey; Gruber, Clemens; Steinkellner, Herta; Diamond, Michael S; Chen, Qiang

    2014-01-01

    Previously, our group engineered a plant-derived monoclonal antibody (MAb) (pHu-E16) that efficiently treated West Nile virus (WNV) infection in mice. In this study, we developed several pHu-E16 variants to improve its efficacy. These variants included a single-chain variable fragment (scFv) of pHu-E16 fused to the heavy chain (HC) constant domains (CH(1-3)) of human IgG (pHu-E16scFv-CH(1-3)) and a tetravalent molecule (Tetra pHu-E16) assembled from pHu-E16scFv-CH(1-3) with a second pHu-E16scFv fused to the light chain (LC) constant region. pHu-E16scFv-CH(1-3) and Tetra pHu-E16 were efficiently expressed and assembled in plants. To assess the impact of differences in N-linked glycosylation on pHu-E16 variant assembly and function, we expressed additional pHu-E16 variants with various combinations of HC and LC components. Our study revealed that proper pairing of HC and LC was essential for the complete N-glycan processing of antibodies in both plant and animal cells. Associated with their distinct N-glycoforms, pHu-E16, pHu-E16scFv-CH(1-3) and Tetra pHu-E16 exhibited differential binding to C1q and specific Fcγ receptors (FcγR). Notably, none of the plant-derived Hu-E16 variants showed antibody-dependent enhancement (ADE) activity in CD32A+ human cells, suggesting the potential of plant-produced antibodies to minimize the adverse effect of ADE. Importantly, all plant-derived MAb variants exhibited at least equivalent in vitro neutralization and in vivo protection in mice compared to mammalian cell-produced Hu-E16. This study demonstrates the capacity of plants to express and assemble a large, complex and functional IgG-like tetravalent mAb variant and also provides insight into the relationship between MAb N-glycosylation, FcγR and C1q binding, and ADE. These new insights may allow the development of safer and cost effective MAb-based therapeutics for flaviviruses, and possibly other pathogens.

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

    Science.gov (United States)

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

    2016-01-01

    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.

  20. Therapeutic monoclonal antibodies and the need for targeted pharmacovigilance in India.

    Science.gov (United States)

    Kalaivani, M; Singh, Abhishank; Kalaiselvan, V

    2015-01-01

    A growing number of innovative mAb therapeutics are on the global market, and biosimilar versions have now also been approved, including in India. Although efficacy and safety is demonstrated prior to approval, targeted pharmacovigilance is essential for the identification and assessment of risk for any mAb products. We analyzed the ADR data related to mAbs reported to the NCC-PvPI through the spontaneous reporting system Vigiflow during April 2011 to February 2014 to identify mAbs with the highest number of ADR including fatal/serious ADR. Only 0.72% reports were related to mAbs. Although 15 mAbs are approved in the country, only 6 mAbs were reported through Vigiflow. Rituximab was highly reported, and no fatal/serious ADR related to any mAbs were reported during the study period. Our study shows that PvPI is effective and robust system in the detection and assessment of risks associated with the use of mAbs.

  1. Dextrose-mediated aggregation of therapeutic monoclonal antibodies in human plasma: Implication of isoelectric precipitation of complement proteins

    Science.gov (United States)

    Luo, Shen; Zhang, Baolin

    2015-01-01

    Many therapeutic monoclonal antibodies (mAbs) are clinically administered through intravenous infusion after mixing with a diluent, e.g., saline, 5% dextrose. Such a clinical setting increases the likelihood of interactions among mAb molecules, diluent, and plasma components, which may adversely affect product safety and efficacy. Avastin® (bevacizumab) and Herceptin® (trastuzumab), but not Remicade® (infliximab), were shown to undergo rapid aggregation upon dilution into 5% dextrose when mixed with human plasma in vitro; however, the biochemical pathways leading to the aggregation were not clearly defined. Here, we show that dextrose-mediated aggregation of Avastin or Herceptin in plasma involves isoelectric precipitation of complement proteins. Using mass spectrometry, we found that dextrose-induced insoluble aggregates were composed of mAb itself and multiple abundant plasma proteins, namely complement proteins C3, C4, factor H, fibronectin, and apolipoprotein. These plasma proteins, which are characterized by an isoelectronic point of 5.5–6.7, lost solubility at the resulting pH in the mixture with formulated Avastin (pH 6.2) and Herceptin (pH 6.0). Notably, switching formulation buffers for Avastin (pH 6.2) and Remicade (pH 7.2) reversed their aggregation profiles. Avastin formed little, if any, insoluble aggregates in dextrose-plasma upon raising the buffer pH to 7.2 or above. Furthermore, dextrose induced pH-dependent precipitation of plasma proteins, with massive insoluble aggregates being detected at pH 6.5–6.8. These data show that isoelectric precipitation of complement proteins is a prerequisite of dextrose-induced aggregation of mAb in human plasma. This finding highlights the importance of assessing the compatibility of a therapeutic mAb with diluent and human plasma during product development. PMID:26338058

  2. Dextrose-mediated aggregation of therapeutic monoclonal antibodies in human plasma: Implication of isoelectric precipitation of complement proteins.

    Science.gov (United States)

    Luo, Shen; Zhang, Baolin

    2015-01-01

    Many therapeutic monoclonal antibodies (mAbs) are clinically administered through intravenous infusion after mixing with a diluent, e.g., saline, 5% dextrose. Such a clinical setting increases the likelihood of interactions among mAb molecules, diluent, and plasma components, which may adversely affect product safety and efficacy. Avastin® (bevacizumab) and Herceptin® (trastuzumab), but not Remicade® (infliximab), were shown to undergo rapid aggregation upon dilution into 5% dextrose when mixed with human plasma in vitro; however, the biochemical pathways leading to the aggregation were not clearly defined. Here, we show that dextrose-mediated aggregation of Avastin or Herceptin in plasma involves isoelectric precipitation of complement proteins. Using mass spectrometry, we found that dextrose-induced insoluble aggregates were composed of mAb itself and multiple abundant plasma proteins, namely complement proteins C3, C4, factor H, fibronectin, and apolipoprotein. These plasma proteins, which are characterized by an isoelectronic point of 5.5-6.7, lost solubility at the resulting pH in the mixture with formulated Avastin (pH 6.2) and Herceptin (pH 6.0). Notably, switching formulation buffers for Avastin (pH 6.2) and Remicade (pH 7.2) reversed their aggregation profiles. Avastin formed little, if any, insoluble aggregates in dextrose-plasma upon raising the buffer pH to 7.2 or above. Furthermore, dextrose induced pH-dependent precipitation of plasma proteins, with massive insoluble aggregates being detected at pH 6.5-6.8. These data show that isoelectric precipitation of complement proteins is a prerequisite of dextrose-induced aggregation of mAb in human plasma. This finding highlights the importance of assessing the compatibility of a therapeutic mAb with diluent and human plasma during product development.

  3. From therapeutic antibodies to chimeric antigen receptors (CARs): making better CARs based on antigen-binding domain.

    Science.gov (United States)

    Wu, Yanling; Jiang, Shibo; Ying, Tianlei

    2016-12-01

    A variety of approaches are being pursued to improve the safety and antitumor potency of chimeric antigen receptor (CAR) T-cell therapy. However, most engineering efforts have thus far been focused on its intracellular signaling domain, while its extracellular antigen-binding domain has received less attention. Areas covered: Herein, the authors summarize the current knowledge of CAR T-cell therapy. Accordingly, they focus on its antigen-binding domain, discuss key considerations for selecting an optimal single-chain variable fragment (scFv) when designing a CAR, and suggest potential directions aimed at developing the next-generation CARs. Expert opinion: The extracellular region of CARs can play a decisive role in their safety and efficacy. Instead of directly translating an available therapeutic mAb to a scFv-based CAR construct, the authors suggest that various CAR-displayed scFvs with different affinity, specificity and binding epitopes against an individual target molecule should be generated and evaluated side-by-side. Incorporating new antibody formats that possess characteristics superior to those of scFvs may be one way to engineer safer and more effective CARs. The authors expect that further CAR engineering will enable us to target more antigens involved in hematological and solid malignancies with minimal side effects to serve unmet clinical needs.

  4. Crystal clear: visualizing the intervention mechanism of the PD-1/PD-L1 interaction by two cancer therapeutic monoclonal antibodies.

    Science.gov (United States)

    Tan, Shuguang; Chen, Danqing; Liu, Kefang; He, Mengnan; Song, Hao; Shi, Yi; Liu, Jun; Zhang, Catherine W-H; Qi, Jianxun; Yan, Jinghua; Gao, Shan; Gao, George F

    2016-12-01

    Antibody-based PD-1/PD-L1 blockade therapies have taken center stage in immunotherapies for cancer, with multiple clinical successes. PD-1 signaling plays pivotal roles in tumor-driven T-cell dysfunction. In contrast to prior approaches to generate or boost tumor-specific T-cell responses, antibody-based PD-1/PD-L1 blockade targets tumor-induced T-cell defects and restores pre-existing T-cell function to modulate antitumor immunity. In this review, the fundamental knowledge on the expression regulations and inhibitory functions of PD-1 and the present understanding of antibody-based PD-1/PD-L1 blockade therapies are briefly summarized. We then focus on the recent breakthrough work concerning the structural basis of the PD-1/PD-Ls interaction and how therapeutic antibodies, pembrolizumab targeting PD-1 and avelumab targeting PD-L1, compete with the binding of PD-1/PD-L1 to interrupt the PD-1/PD-L1 interaction. We believe that this structural information will benefit the design and improvement of therapeutic antibodies targeting PD-1 signaling.

  5. A Novel Platform for the Potentiation of Therapeutic Antibodies Based on Antigen-Dependent Formation of IgG Hexamers at the Cell Surface.

    Directory of Open Access Journals (Sweden)

    Rob N de Jong

    2016-01-01

    Full Text Available IgG antibodies can organize into ordered hexamers on cell surfaces after binding their antigen. These hexamers bind the first component of complement C1 inducing complement-dependent target cell killing. Here, we translated this natural concept into a novel technology platform (HexaBody technology for therapeutic antibody potentiation. We identified mutations that enhanced hexamer formation and complement activation by IgG1 antibodies against a range of targets on cells from hematological and solid tumor indications. IgG1 backbones with preferred mutations E345K or E430G conveyed a strong ability to induce conditional complement-dependent cytotoxicity (CDC of cell lines and chronic lymphocytic leukemia (CLL patient tumor cells, while retaining regular pharmacokinetics and biopharmaceutical developability. Both mutations potently enhanced CDC- and antibody-dependent cellular cytotoxicity (ADCC of a type II CD20 antibody that was ineffective in complement activation, while retaining its ability to induce apoptosis. The identified IgG1 Fc backbones provide a novel platform for the generation of therapeutics with enhanced effector functions that only become activated upon binding to target cell-expressed antigen.

  6. Crystal clear: visualizing the intervention mechanism of the PD-1/PD-L1 interaction by two cancer therapeutic monoclonal antibodies

    Directory of Open Access Journals (Sweden)

    Shuguang Tan

    2016-11-01

    Full Text Available Abstract Antibody-based PD-1/PD-L1 blockade therapies have taken center stage in immunotherapies for cancer, with multiple clinical successes. PD-1 signaling plays pivotal roles in tumor-driven T-cell dysfunction. In contrast to prior approaches to generate or boost tumor-specific T-cell responses, antibody-based PD-1/PD-L1 blockade targets tumor-induced T-cell defects and restores pre-existing T-cell function to modulate antitumor immunity. In this review, the fundamental knowledge on the expression regulations and inhibitory functions of PD-1 and the present understanding of antibody-based PD-1/PD-L1 blockade therapies are briefly summarized. We then focus on the recent breakthrough work concerning the structural basis of the PD-1/PD-Ls interaction and how therapeutic antibodies, pembrolizumab targeting PD-1 and avelumab targeting PD-L1, compete with the binding of PD-1/PD-L1 to interrupt the PD-1/PD-L1 interaction. We believe that this structural information will benefit the design and improvement of therapeutic antibodies targeting PD-1 signaling.

  7. C-type lectin-like molecule-1 (CLL1)-targeted TRAIL augments the tumoricidal activity of granulocytes and potentiates therapeutic antibody-dependent cell-mediated cytotoxicity.

    Science.gov (United States)

    Wiersma, Valerie R; de Bruyn, Marco; Shi, Ce; Gooden, Marloes J M; Wouters, Maartje C A; Samplonius, Douwe F; Hendriks, Djoke; Nijman, Hans W; Wei, Yunwei; Zhou, Jin; Helfrich, Wijnand; Bremer, Edwin

    2015-01-01

    The therapeutic effect of anti-cancer monoclonal antibodies stems from their capacity to opsonize targeted cancer cells with subsequent phagocytic removal, induction of antibody-dependent cell-mediated cytotoxicity (ADCC) or induction of complement-mediated cytotoxicity (CDC). The major immune effector cells involved in these processes are natural killer (NK) cells and granulocytes. The latter and most prevalent blood cell population contributes to phagocytosis, but is not effective in inducing ADCC. Here, we report that targeted delivery of the tumoricidal protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to granulocyte marker C-type lectin-like molecule-1 (CLL1), using fusion protein CLL1:TRAIL, equips granulocytes with high levels of TRAIL. Upon CLL1-selective binding of this fusion protein, granulocytes acquire additional TRAIL-mediated cytotoxic activity that, importantly, potentiates antibody-mediated cytotoxicity of clinically used therapeutic antibodies (e.g., rituximab, cetuximab). Thus, CLL1:TRAIL could be used as an adjuvant to optimize the clinical potential of anticancer antibody therapy by augmenting tumoricidal activity of granulocytes.

  8. Antiviral Functions of Human Immunodeficiency Virus Type 1 (HIV-1)-Specific IgG Antibodies: Effects of Antiretroviral Therapy and Implications for Therapeutic HIV-1 Vaccine Design.

    Science.gov (United States)

    French, Martyn A; Tjiam, M Christian; Abudulai, Laila N; Fernandez, Sonia

    2017-01-01

    . As HIV-1 infects cells in GCs and induces GC dysfunction, which may persist during ART, strategies for boosting HIV-1-specific IgG antibody responses should include early commencement of ART and possibly the use of particular antiretroviral drugs to optimize drug levels in lymphoid follicles. Finally, enhancing particular functions of HIV-1-specific IgG antibody responses by using adjuvants or cytokines to modulate the IgG subclass content of the antibody response might be investigated in NHP models of HIV-1 infection and during trials of therapeutic vaccines in HIV patients.

  9. Estimation of dose requirements for sustained in vivo activity of a therapeutic human anti-CD20 antibody

    NARCIS (Netherlands)

    Bleeker, Wim K.; Munk, Martin E.; Mackus, Wendy J. M.; van den Brakel, Jeroen H. N.; Pluyter, Marielle; Glennie, Martin J.; van de Winkel, Jan G. J.; Parren, Paul W. H. I.

    We evaluated the dose requirements for sustained in vivo activity of ofatumumab, a human anti-CD20 antibody under development for the treatment of B cell-mediated diseases. In a mouse xenograft model, a single dose, resulting in an initial plasma antibody concentration of 5 mu g/ml, which was

  10. Antibody-mediated phagocytosis contributes to the anti-tumor activity of the therapeutic antibody daratumumab in lymphoma and multiple myeloma

    DEFF Research Database (Denmark)

    Overdijk, M. B.; Verploegen, S.; Bogels, M.

    2015-01-01

    in MM and other hematological tumors, led us to investigate the contribution of antibody-dependent, macrophage-mediated phagocytosis to DARA's mechanism of action. Live cell imaging revealed that DARA efficiently induced macrophage-mediated phagocytosis, in which individual macrophages rapidly...

  11. Amelioration of murine passive immune thrombocytopenia by IVIg and a therapeutic monoclonal CD44 antibody does not require the Myd88 signaling pathway.

    Directory of Open Access Journals (Sweden)

    Andrew R Crow

    Full Text Available Immune thrombocytopenia (ITP is an autoimmune bleeding disorder characterized by a low platelet count and the production of anti-platelet antibodies. The majority of ITP patients have antibodies to platelet integrin α(IIbβ₃ (GPIIbIIIa which can direct platelet phagocytosis by macrophages. One effective treatment for patients with ITP is intravenous immunoglobulin (IVIg which rapidly reverses thrombocytopenia. The exact mechanism of IVIg action in human patients is unclear, although in mouse models of passive ITP, IVIg can rapidly increase platelet counts in the absence of adaptive immunity. Another antibody therapeutic that can similarly increase platelet counts independent of adaptive immunity are CD44 antibodies. Toll-like receptors (TLRs are pattern recognition receptors which play a central role in helping direct the innate immune system. Dendritic cells, which are notable for their expression of TLRs, have been directly implicated in IVIg function as an initiator cell, while CD44 can associate with TLR2 and TLR4. We therefore questioned whether IVIg, or the therapeutic CD44 antibody KM114, mediate their ameliorative effects in a manner dependent upon normal TLR function. Here, we demonstrate that the TLR4 agonist LPS does not inhibit IVIg or KM114 amelioration of antibody-induced thrombocytopenia, and that these therapeutics do not ameliorate LPS-induced thrombocytopenia. IVIg was able to significantly ameliorate murine ITP in C3H/HeJ mice which have defective TLR4. All known murine TLRs except TLR3 utilize the Myd88 adapter protein to drive TLR signaling. Employing Myd88 deficient mice, we found that both IVIg and KM114 ameliorate murine ITP in Myd88 deficient mice to the same extent as normal mice. Thus both IVIg and anti-CD44 antibody can mediate their ameliorative effects in murine passive ITP independent of the Myd88 signaling pathway. These data help shed light on the mechanism of action of IVIg and KM114 in the amelioration of

  12. Broadly neutralizing human monoclonal JC polyomavirus VP1–specific antibodies as candidate therapeutics for progressive multifocal leukoencephalopathy

    Science.gov (United States)

    Jelcic, Ivan; Combaluzier, Benoit; Jelcic, Ilijas; Faigle, Wolfgang; Senn, Luzia; Reinhart, Brenda J.; Ströh, Luisa; Nitsch, Roger M.; Stehle, Thilo; Sospedra, Mireia; Grimm, Jan; Martin, Roland

    2016-01-01

    In immunocompromised individuals, JC polyomavirus (JCPyV) may mutate and gain access to the central nervous system resulting in progressive multifocal leukoencephalopathy (PML), an often fatal opportunistic infection for which no treatments are currently available. Despite recent progress, the contribution of JCPyV-specific humoral immunity to controlling asymptomatic infection throughout life and to eliminating JCPyV from the brain is poorly understood. We examined antibody responses against JCPyV major capsid protein VP1 (viral protein 1) variants in the serum and cerebrospinal fluid (CSF) of healthy donors (HDs), JCPyV-positive multiple sclerosis patients treated with the anti-VLA-4 monoclonal antibody natalizumab (NAT), and patients with NAT-associated PML. Before and during PML, CSF antibody responses against JCPyV VP1 variants show “recognition holes”; however, upon immune reconstitution, CSF antibody titers rise, then recognize PML-associated JCPyV VP1 variants, and may be involved in elimination of the virus. We therefore reasoned that the memory B cell repertoire of individuals who recovered from PML could be a source for the molecular cloning of broadly neutralizing antibodies for passive immunization. We generated a series of memory B cell-derived JCPyV VP1-specific human monoclonal antibodies from HDs and a patient with NAT-associated PML-immune reconstitution inflammatory syndrome (IRIS). These antibodies exhibited diverse binding affinity, cross-reactivity with the closely related BK polyomavirus, recognition of PML-causing VP1 variants, and JCPyV neutralization. Almost all antibodies with exquisite specificity for JCPyV, neutralizing activity, recognition of all tested JCPyV PML variants, and high affinity were derived from one patient who had recovered from PML. These antibodies are promising drug candidates for the development of a treatment of PML. PMID:26400911

  13. Towards Protein Crystallization as a Process Step in Downstream Processing of Therapeutic Antibodies: Screening and Optimization at Microbatch Scale

    Science.gov (United States)

    Zang, Yuguo; Kammerer, Bernd; Eisenkolb, Maike; Lohr, Katrin; Kiefer, Hans

    2011-01-01

    Crystallization conditions of an intact monoclonal IgG4 (immunoglobulin G, subclass 4) antibody were established in vapor diffusion mode by sparse matrix screening and subsequent optimization. The procedure was transferred to microbatch conditions and a phase diagram was built showing surprisingly low solubility of the antibody at equilibrium. With up-scaling to process scale in mind, purification efficiency of the crystallization step was investigated. Added model protein contaminants were excluded from the crystals to more than 95%. No measurable loss of Fc-binding activity was observed in the crystallized and redissolved antibody. Conditions could be adapted to crystallize the antibody directly from concentrated and diafiltrated cell culture supernatant, showing purification efficiency similar to that of Protein A chromatography. We conclude that crystallization has the potential to be included in downstream processing as a low-cost purification or formulation step. PMID:21966480

  14. Towards protein crystallization as a process step in downstream processing of therapeutic antibodies: screening and optimization at microbatch scale.

    Directory of Open Access Journals (Sweden)

    Yuguo Zang

    Full Text Available Crystallization conditions of an intact monoclonal IgG4 (immunoglobulin G, subclass 4 antibody were established in vapor diffusion mode by sparse matrix screening and subsequent optimization. The procedure was transferred to microbatch conditions and a phase diagram was built showing surprisingly low solubility of the antibody at equilibrium. With up-scaling to process scale in mind, purification efficiency of the crystallization step was investigated. Added model protein contaminants were excluded from the crystals to more than 95%. No measurable loss of Fc-binding activity was observed in the crystallized and redissolved antibody. Conditions could be adapted to crystallize the antibody directly from concentrated and diafiltrated cell culture supernatant, showing purification efficiency similar to that of Protein A chromatography. We conclude that crystallization has the potential to be included in downstream processing as a low-cost purification or formulation step.

  15. Antithyroglobulin antibody

    Science.gov (United States)

    Thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Hypothyroidism - thyroglobulin antibody; Thyroiditis - thyroglobulin antibody; Graves disease - thyroglobulin antibody; Underactive thyroid - thyroglobulin antibody

  16. Comprehensive Analysis of the Therapeutic IgG4 Antibody Pembrolizumab: Hinge Modification Blocks Half Molecule Exchange In Vitro and In Vivo.

    Science.gov (United States)

    Yang, Xiaoyu; Wang, Fengqiang; Zhang, Ying; Wang, Larry; Antonenko, Svetlana; Zhang, Shuli; Zhang, Yi Wei; Tabrizifard, Mohammad; Ermakov, Grigori; Wiswell, Derek; Beaumont, Maribel; Liu, Liming; Richardson, Daisy; Shameem, Mohammed; Ambrogelly, Alexandre

    2015-12-01

    IgG4 antibodies are evolving as an important class of cancer immunotherapies. However, human IgG4 can undergo Fab arm (half molecule) exchange with other IgG4 molecules in vivo. The hinge modification by a point mutation (S228P) prevents half molecule exchange of IgG4. However, the experimental confirmation is still expected by regulatory agencies. Here, we report for the first time the extensive analysis of half molecule exchange for a hinge-modified therapeutic IgG4 molecule, pembrolizumab (Keytruda) targeting programmed death 1 (PD1) receptor that was approved for advanced melanoma. Studies were performed in buffer or human serum using multiple exchange partners including natalizumab (Tysabri) and human IgG4 pool. Formation of bispecific antibodies was monitored by fluorescence resonance energy transfer, exchange with Fc fragments, mixed mode chromatography, immunoassays, and liquid chromatography-mass spectrometry. The half molecule exchange was also examined in vivo in SCID (severe combined immunodeficiency) mice. Both in vitro and in vivo results indicate that the hinge modification in pembrolizumab prevented half molecule exchange, whereas the unmodified counterpart anti-PD1 wt showed active exchange activity with other IgG4 antibodies or self-exchange activity with its own molecules. Our work, as an example expected for meeting regulatory requirements, contributes to establish without ambiguity that hinge-modified IgG4 antibodies are suitable for biotherapeutic applications. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. Review article: is there an optimal therapeutic regimen for antimitochondrial antibody-negative primary biliary cirrhosis (autoimmune cholangitis)?

    Science.gov (United States)

    Gisbert, J P; Jones, E A; Pajares, J M; Moreno-Otero, R

    2003-01-01

    Testing for antimitochondrial antibodies is the most useful laboratory procedure in the diagnosis of primary biliary cirrhosis; nevertheless, 5-10% of patients with typical features of primary biliary cirrhosis do not have detectable antimitochondrial antibodies, their condition being referred to as antimitochondrial antibody-negative primary biliary cirrhosis or "autoimmune cholangitis". Uncertainty exists whether antimitochondrial antibody-positive and -negative primary biliary cirrhosis represent distinct entities. We reviewed studies that compared: (i) the clinical, laboratory and histological characteristics of antimitochondrial antibody-positive and -negative primary biliary cirrhosis; (ii) the response to treatment of both conditions; and (iii) the response of autoimmune cholangitis to ursodeoxycholic acid and immunosuppressive therapy. Antimitochondrial antibody-positive and -negative primary biliary cirrhosis were characterized by similar clinical, laboratory and histological abnormalities, clinical course and survival. Antimitochondrial antibody status did not seem to affect the response to ursodeoxycholic acid. At present, the efficacy of therapies for autoimmune cholangitis has not been established in controlled trials. Of 52 patients with autoimmune cholangitis treated with ursodeoxycholic acid in 13 uncontrolled studies, 83% had serum biochemical improvement. Also, a favourable effect of immunosuppressive drugs occurred in 57% of 54 patients with autoimmune cholangitis in 17 uncontrolled studies. Each of these trials included very few patients and most evaluated the effects of treatment on surrogate markers of disease only. No marker that consistently distinguished patients who would respond favourably to ursodeoxycholic acid or immunosuppression was apparent. Consequently, treatment is, at present, empirical. However, ursodeoxycholic acid may be given when histology reveals bile duct lesions, whereas immunosuppressive therapy should probably be

  18. Modulating Therapeutic Activity and Toxicity of Pyrrolobenzodiazepine Antibody-Drug Conjugates with Self-Immolative Disulfide Linkers.

    Science.gov (United States)

    Pillow, Thomas H; Schutten, Melissa; Yu, Shang-Fan; Ohri, Rachana; Sadowsky, Jack; Poon, Kirsten Achilles; Solis, Willy; Zhong, Fiona; Del Rosario, Geoffrey; Go, Mary Ann T; Lau, Jeffrey; Yee, Sharon; He, Jintang; Liu, Luna; Ng, Carl; Xu, Keyang; Leipold, Douglas D; Kamath, Amrita V; Zhang, Donglu; Masterson, Luke; Gregson, Stephen J; Howard, Philip W; Fang, Fan; Chen, Jinhua; Gunzner-Toste, Janet; Kozak, Katherine K; Spencer, Susan; Polakis, Paul; Polson, Andrew G; Flygare, John A; Junutula, Jagath R

    2017-05-01

    A novel disulfide linker was designed to enable a direct connection between cytotoxic pyrrolobenzodiazepine (PBD) drugs and the cysteine on a targeting antibody for use in antibody-drug conjugates (ADCs). ADCs composed of a cysteine-engineered antibody were armed with a PBD using a self-immolative disulfide linker. Both the chemical linker and the antibody site were optimized for this new bioconjugation strategy to provide a highly stable and efficacious ADC. This novel disulfide ADC was compared with a conjugate containing the same PBD drug, but attached to the antibody via a peptide linker. Both ADCs had similar efficacy in mice bearing human tumor xenografts. Safety studies in rats revealed that the disulfide-linked ADC had a higher MTD than the peptide-linked ADC. Overall, these data suggest that the novel self-immolative disulfide linker represents a valuable way to construct ADCs with equivalent efficacy and improved safety. Mol Cancer Ther; 16(5); 871-8. ©2017 AACR . ©2017 American Association for Cancer Research.

  19. Development of a novel anti-human aspartyl-(asparaginyl) β-hydroxylase monoclonal antibody with diagnostic and therapeutic potential.

    Science.gov (United States)

    Huyan, Ting; Li, Qi; Dong, Dan-Dan; Yang, Hui; Xue, Xiao-Ping; Huang, Qing-Sheng

    2017-03-01

    Human aspartyl-(asparaginyl)-β-hydroxylase (HAAH) has recently been the subject of several studies, as it was previously observed to be overexpressed in numerous types of carcinoma cells and tissues in patient tumor samples. HAAH has been implicated in tumor invasion and metastasis, indicating that it may be an important target and biomarker for tumor diagnosis and treatment. However, the immunological tools currently available for the study of this protein, including monoclonal antibodies, are limited, as is the present knowledge regarding the role of HAAH in tumor therapy and diagnosis. In the present study, a recombinant C-terminal domain of HAAH was expressed in Pichia pastoris and a novel monoclonal antibody (mAb) targeting HAAH (HAAH-C) was constructed. Immunofluorescence and antibody-dependent cellular cytotoxicity (ADCC) assays were used to demonstrate the specificity and ADCC activity of this antibody. The results demonstrated that this anti-C-terminal HAAH mAB, in combination with an existing anti-N terminal HAAH mAb, exhibited a high response to native HAAH from carcinoma cell culture supernatant, as measured with a double antibody sandwich enzyme-linked immunosorbent assay. This validated novel mAB-HAAH-C may prompt further studies into the underlying mechanisms of HAAH, and the exploration of its potential in tumor diagnosis and therapy.

  20. Buffer-free therapeutic antibody preparations provide a viable alternative to conventionally buffered solutions: from protein buffer capacity prediction to bioprocess applications.

    Science.gov (United States)

    Bahrenburg, Sven; Karow, Anne R; Garidel, Patrick

    2015-04-01

    Protein therapeutics, including monoclonal antibodies (mAbs), have significant buffering capacity, particularly at concentrations>50 mg/mL. This report addresses pH-related issues critical to adoption of self-buffered monoclonal antibody formulations. We evaluated solution conditions with protein concentrations ranging from 50 to 250 mg/mL. Samples were both buffer-free and conventionally buffered with citrate. Samples were non-isotonic or adjusted for isotonicity with NaCl or trehalose. Studies included accelerated temperature stability tests, shaking stability studies, and pH changes in infusion media as protein concentrate is added. We present averaged buffering slopes of capacity that can be applied to any mAb and present a general method for calculating buffering capacity of buffer-free, highly concentrated antibody liquid formulations. In temperature stability tests, neither buffer-free nor conventionally buffered solution conditions showed significant pH changes. Conventionally buffered solutions showed significantly higher opalescence than buffer-free ones. In general, buffer-free solution conditions showed less aggregation than conventionally buffered solutions. Shaking stability tests showed no differences between buffer-free and conventionally buffered solutions. "In-use" preparation experiments showed that pH in infusion bag medium can rapidly approximate that of self-buffered protein concentrate as concentrate is added. In summary, the buffer capacity of proteins can be predicted and buffer-free therapeutic antibody preparations provide a viable alternative to conventionally buffered solutions. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. The Central Role for Microenvironment in B-Cell Malignancies: Recent Insights into Synergistic Effects of its Therapeutic Targeting and Anti-CD20 Antibodies.

    Science.gov (United States)

    Ahmadzadeh, Vahideh; Tofigh, Roghaye; Farajnia, Safar; Pouladi, Nasser

    2016-01-01

    Most B-cell-related disorders can be cured with conventional agents; however, relapse is common, creating a need for additional therapeutic options. In agreement, recent biomarker studies corroborate the role played by functional crosstalk between malignant B cells and microenvironment which have added texture to clinical outcome. Here we outline the essential role of the tumor-associated niche in B-cell Lymphoma/Leukemia pathogenesis, in an attempt to optimize the use of microenvironment-targeted drugs and anti-CD20 antibodies in the various subsets.

  2. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    DEFF Research Database (Denmark)

    Da Roit, F.; Engelberts, P. J.; Taylor, R. P.

    2015-01-01

    The novel Bruton tyrosine kinase inhibitor ibrutinib and phosphatidyl-4-5-biphosphate 3-kinase-delta inhibitor idelalisib are promising drugs for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma, either alone or in combination with anti-CD20 antibodies. We investigate......M were weaker than those observed with ibrutinib at the same concentration. We conclude that the design of combined treatment schedules of anti-CD20 antibodies with these kinase inhibitors should consider the multiple negative interactions between these two classes of drugs....

  3. Isotype Diversification of IgG Antibodies to HIV Gag Proteins as a Therapeutic Vaccination Strategy for HIV Infection

    Directory of Open Access Journals (Sweden)

    Sonia Fernandez

    2013-08-01

    Full Text Available The development of vaccines to treat and prevent human immunodeficiency virus (HIV infection has been hampered by an incomplete understanding of “protective” immune responses against HIV. Natural control of HIV-1 infection is associated with T-cell responses against HIV-1 Gag proteins, particularly CD8+ T-cell responses restricted by “protective” HLA-B alleles, but other immune responses also contribute to immune control. These immune responses appear to include IgG antibodies to HIV-1 Gag proteins, interferon-a-dependant natural killer (NK cell responses and plasmacytoid dendritic cell (pDC responses. Here, it is proposed that isotype diversification of IgG antibodies against HIV-1 Gag proteins, to include IgG2, as well as IgG3 and IgG1 antibodies, will broaden the function of the antibody response and facilitate accessory cell responses against HIV-1 by NK cells and pDCs. We suggest that this should be investigated as a vaccination strategy for HIV-1 infection.

  4. Glycosylation profiling of a therapeutic recombinant monoclonal antibody with two N-linked glycosylation sites using liquid chromatography coupled to a hybrid quadrupole time-of-flight mass spectrometer.

    Science.gov (United States)

    Lim, Amareth; Reed-Bogan, Angelia; Harmon, Bryan J

    2008-04-15

    Monoclonal antibodies have been used increasingly as therapeutic agents to target various diseases. Although most monoclonal antibodies have only one N-linked glycosylation site in the Fc region, N-linked glycosylation sites in the Fab region have also been observed. Because glycosylation of a monoclonal antibody can have a significant impact on its effector function, efficacy, clearance, and immunogenicity, it is essential to assess the glycosylation profile during cell line and clone selection studies and to assess the impact of cell culture conditions on the glycoform distribution during process optimization studies to ensure that the antibody is being produced with appropriate and consistent glycosylation. This article describes a liquid chromatography-mass spectrometry-based approach, in combination with papain digestion and partial reduction, to obtain site-specific glycosylation profile information for a therapeutic monoclonal antibody with two N-linked glycosylation sites in the heavy chain.

  5. Immunoliposome co-delivery of bufalin and anti-CD40 antibody adjuvant induces synergetic therapeutic efficacy against melanoma

    National Research Council Canada - National Science Library

    Li, Ying; Yuan, Jiani; Yang, Qian; Cao, Wei; Zhou, Xuanxuan; Xie, Yanhua; Tu, Honghai; Zhang, Ya; Wang, Siwang

    2014-01-01

    .... The purpose of this study was to design and evaluate immunoliposome co-delivery of bufalin and anti-CD40 to induce synergetic therapeutic efficacy while eliminating systemic side effects. Bufalin liposomes (BFL...

  6. A screening tool for therapeutic monoclonal antibodies: Identifying the most stable protein and its best formulation based on thioflavin T binding.

    Science.gov (United States)

    Kayser, Veysel; Chennamsetty, Naresh; Voynov, Vladimir; Helk, Bernhard; Forrer, Kurt; Trout, Bernhardt L

    2012-01-01

    The lack of a fast selection method to identify the most stable protein is one of the major challenges for developing successful therapeutic protein formulations more rapidly. The swift and accurate detection of small amounts of aggregates is another problem since aggregates may trigger an immunological response and the aggregation decreases the biological activity of the antibody. Here we present an alternative method for initial screening of the aggregation propensity of proteins, using monoclonal antibodies (mAb) as an example and thioflavin T (ThT) binding. The major advantage of ThT binding is the short duration of testing compared with size-exclusion chromatography (SEC) measurements that can take 6 months or more even under accelerated conditions. The tendency to aggregate of each therapeutic human mAb probed with the ThT assay, together with SEC, is employed to formulate the ranking of mAb aggregation. ThT binding can determine the propensity of proteins to aggregate in a few days, illustrating that ThT binding would be a valuable screening tool. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A novel two-component Tobacco mosaic virus-based vector system for high-level expression of multiple therapeutic proteins including a human monoclonal antibody in plants.

    Science.gov (United States)

    Roy, Gourgopal; Weisburg, Sangeetha; Rabindran, Shailaja; Yusibov, Vidadi

    2010-09-15

    Expression of multiple therapeutic proteins from Tobacco mosaic virus (TMV)-based vectors was not successful when plants were coinoculated with a mixture of two TMV vectors engineered to express two foreign genes individually. Here, we have engineered and developed a defective RNA (dRNA)-based TMV vector (dRT-V) that utilizes two components of the same virus, with the dRNA component depending on the helper virus for replication. Agrobacterium-mediated coinoculation of Nicotiana benthamiana plants with both components of the dRT-V resulted in high-level expression of a human growth hormone and a lichenase-fused lethal factor protein of Bacillus anthracis. Furthermore, both heavy and light chains were expressed and assembled into a monoclonal antibody (mAb) specific to the protective antigen of B. anthracis, and the average yield of the purified antibody obtained was 120 mg/kg of fresh tissue. Our data suggest that dRT-V has a potential for rapid, cost-effective, large-scale manufacturing of multiple therapeutic proteins including mAbs in response to any biological emergencies. Copyright 2010 Elsevier Inc. All rights reserved.

  8. Feasibility study of semi-selective protein precipitation with salt-tolerant copolymers for industrial purification of therapeutic antibodies.

    Science.gov (United States)

    Capito, Florian; Bauer, Johann; Rapp, Almut; Schröter, Christian; Kolmar, Harald; Stanislawski, Bernd

    2013-11-01

    We present a feasibility study for an antibody capturing process from clarified cell culture fluid using semi-selective protein precipitation with salt-tolerant copolymers. Protein precipitation is mediated by hydrophobic and electrostatic interactions with the copolymer that can be customized for the respective target. Precipitation yield with different copolymers at ionic strength of 2-22.5 mS cm⁻¹ and pH 5.0-pH 5.7 was evaluated using pure monoclonal antibody solutions. Optimized parameters were used to elucidate yield and purity of various antibodies precipitated at physiological conditions from cell culture fluid of CHO, NS0, and SP2/0 cell culture fluid. Precipitated protein was easily redissolved in small volume, enabling concentrating monoclonal antibodies (mAb) more than 40-fold and up to 100-fold, while residual polymer was removed to >98% using cationic polymer attached to silica flakes. mAb recovery of >90% and host cell protein clearance of >80% were achieved, not requiring any pre-dilution of cell culture fluid. Precipitation showed no impact on mAb binding affinity when compared to non-precipitated mAb. The obtained yield and purity were lower compared to a protein A based purification and loss of mAb was factor 1.5-3.0 higher. Yet, for high titer mAb purification processes being implemented in the future, precipitation is an attractive option due to its ease of scalability and cost-effectiveness. © 2013 Wiley Periodicals, Inc.

  9. Anti-transforming growth factor antibody at low but not high doses limits cyclosporine-mediated nephrotoxicity without altering rat cardiac allograft survival: potential of therapeutic applications.

    Science.gov (United States)

    Khanna, Ashwani K; Plummer, Matthew S; Hilton, Gail; Pieper, Galen M; Ledbetter, Steven

    2004-12-21

    Long-term treatment of cardiac transplant recipients with cyclosporine results in a progressive decline in kidney function in a large number of patients. This complication is one of the most important prognostic parameters that determine the outcome of cardiac transplantation. Transforming growth factor-beta (TGF-beta) is one of the most potent mediators of the fibrogenic effects of cyclosporine. With the use of an experimental rodent model, heterotopic heart transplantation was performed, creating histocompatibility-disparate allografts. Because TGF-beta in part mediates both the immunosuppressive and nephrotoxic effects of cyclosporine, recipients were treated with cyclosporine with and without anti-TGF-beta antibody to determine whether anti-TGF-beta antibody could reduce the nephrotoxic effects of cyclosporine. Intrarenal expression of TGF-beta, collagen, fibronectin, matrix metalloproteinase-2, and tissue inhibitor of metalloproteinase-2 was studied with the use of reverse transcription-polymerase chain reaction. Intrarenal expression of TGF-beta protein was studied by immunohistochemistry and with the use of ELISA to quantify circulating levels of TGF-beta protein in plasma. Cyclosporine-induced graft survival (immunosuppressive effect) was abrogated with a higher concentration (2.5 mg/kg) of anti-TGF-beta antibody, whereas a lower concentration (1 mg/kg) inhibited both cyclosporine-induced expression of fibrogenic molecules and renal toxicity. These results provide credence to the pivotal role of TGF-beta in immunosuppression-associated renal toxicity in recipients of cardiac transplantation. Furthermore, these findings support a potentially significant therapeutic use of optimal concentration of anti-TGF-beta antibody to ameliorate cyclosporine-associated nephrotoxicity in cardiac transplant recipients.

  10. Enhanced antibody responses elicited by a CpG adjuvant do not improve the protective effect of an aldrithiol-2-inactivated simian immunodeficiency virus therapeutic AIDS vaccine.

    Science.gov (United States)

    Wang, Yichuan; Blozis, Shelley A; Lederman, Michael; Krieg, Arthur; Landay, Alan; Miller, Christopher J

    2009-04-01

    The potential benefit of using unmethylated CpG oligoribodeoxynucleotides (ODN) as an adjuvant in a therapeutic simian immunodeficiency virus (SIV) vaccine consisting of AT2-inactivated SIVmac239 was evaluated in SIV-infected rhesus macaques receiving antiretroviral therapy (ART). We hypothesized that using CpG ODN as an adjuvant in therapeutic vaccination would enhance SIV-specific immune responses and suppress SIV replication after ART was stopped. To test our hypothesis, we immunized chronically SIV-infected rhesus macaques receiving ART with one of the following therapeutic vaccines: (i) AT2-inactivated SIVmac239, (ii) CpG10103 plus AT2-inactivated SIVmac239, (iii) CpG10103, and (iv) saline. While immunization with CpG plus AT2-SIVmac239 significantly increased SIV-specific immunoglobulin G (IgG) antibody titers, the mean plasma viral RNA (vRNA) level in these animals after ART did not differ from those of saline-treated animals. The AT2-inactivated SIVmac239-immunized animal group had a significantly higher mean SIV-specific gamma interferon T-cell response after three immunizations and lower plasma vRNA levels for 6 weeks after ART was withdrawn compared to the saline-treated animal group. Compared to the saline control group, the animal group treated with CpG alone had a significantly higher mean SIV-specific lymphocyte proliferation index and a higher rate of plasma vRNA rebound after ART. These results demonstrate that while the use of CpG as an adjuvant enhances SIV-specific antibody responses, this does not improve the control of SIV replication after ART is stopped. The lack of benefit may be related to the high levels of SIV-specific lymphocyte proliferation in the CpG adjuvant group.

  11. Therapeutic efficacy of c-kit-targeted radioimmunotherapy using 90Y-labeled anti-c-kit antibodies in a mouse model of small cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Chisato Yoshida

    Full Text Available UNLABELLED: Small cell lung cancer (SCLC is an aggressive tumor and prognosis remains poor. Therefore, the development of more effective therapy is needed. We previously reported that high levels of an anti-c-kit antibody (12A8 accumulated in SCLC xenografts. In the present study, we evaluated the efficacy of two antibodies (12A8 and 67A2 for radioimmunotherapy (RIT of an SCLC mouse model by labeling with the (90Y isotope. METHODS: (111In- or (125I-labeled antibodies were evaluated in vitro by cell binding, competitive inhibition and cellular internalization assays in c-kit-expressing SY cells and in vivo by biodistribution in SY-bearing mice. Therapeutic efficacy of (90Y-labeled antibodies was evaluated in SY-bearing mice upto day 28 and histological analysis was conducted at day 7. RESULTS: [(111In]12A8 and [(111In]67A2 specifically bound to SY cells with high affinity (8.0 and 1.9 nM, respectively. 67A2 was internalized similar to 12A8. High levels of [(111In]12A8 and [(111In]67A2 accumulated in tumors, but not in major organs. [(111In]67A2 uptake by the tumor was 1.7 times higher than for [(111In]12A8. [(90Y]12A8, but not [(90Y]67A2, suppressed tumor growth in a dose-dependent manner. Tumors treated with 3.7 MBq of [(90Y]12A8, and 1.85 and 3.7 MBq of [(90Y]67A2 (absorbed doses were 21.0, 18.0 and 35.9 Gy, respectively almost completely disappeared approximately 2 weeks after injection, and regrowth was not observed except for in one mouse treated with 1.85 MBq [(90Y]67A2. The area of necrosis and fibrosis increased depending on the RIT effect. Apoptotic cell numbers increased with increased doses of [(90Y]12A8, whereas no dose-dependent increase was observed following [(90Y]67A2 treatment. Body weight was temporarily reduced but all mice tolerated the RIT experiments well. CONCLUSION: Treatment with [(90Y]12A8 and [(90Y]67A2 achieved a complete therapeutic response when SY tumors received an absorbed dose greater than 18 Gy and thus are

  12. Therapeutic targeting of tumor growth and angiogenesis with a novel anti-S100A4 monoclonal antibody.

    Directory of Open Access Journals (Sweden)

    Jose Luis Hernández

    Full Text Available S100A4, a member of the S100 calcium-binding protein family secreted by tumor and stromal cells, supports tumorigenesis by stimulating angiogenesis. We demonstrated that S100A4 synergizes with vascular endothelial growth factor (VEGF, via the RAGE receptor, in promoting endothelial cell migration by increasing KDR expression and MMP-9 activity. In vivo overexpression of S100A4 led to a significant increase in tumor growth and vascularization in a human melanoma xenograft M21 model. Conversely, when silencing S100A4 by shRNA technology, a dramatic decrease in tumor development of the pancreatic MiaPACA-2 cell line was observed. Based on these results we developed 5C3, a neutralizing monoclonal antibody against S100A4. This antibody abolished endothelial cell migration, tumor growth and angiogenesis in immunodeficient mouse xenograft models of MiaPACA-2 and M21-S100A4 cells. It is concluded that extracellular S100A4 inhibition is an attractive approach for the treatment of human cancer.

  13. Improving tumor targeting and therapeutic potential of Salmonella VNP20009 by displaying cell surface CEA-specific antibodies.

    Science.gov (United States)

    Bereta, Michal; Hayhurst, Andrew; Gajda, Mariusz; Chorobik, Paulina; Targosz, Marta; Marcinkiewicz, Janusz; Kaufman, Howard L

    2007-05-22

    Genetically modified Salmonella typhimurium VNP20009 (VNP) is a useful vehicle for cancer therapy and vaccine development but exhibits limited tumor targeting in vivo. We engineered a novel VNP derivative that expressed carcinoembryonic antigen (CEA)-specific single chain antibody fragments (scFv) on the cell surface to increase tumor-specific targeting. There was significant scFv cell surface display visualized by flow cytometry and confocal microscopy when cells were probed with fluorescently labeled CEA. Atomic force microscopy (AFM) measurements on whole bacteria confirmed binding of unlabeled CEA to the displayed scFv. The modified VNP strain exhibited increased localization in the upper gastrointestinal tract of CEA transgenic mice and accumulated in CEA-expressing tumors. Furthermore, treatment with a single dose of the VNP derivative inhibited growth of MC38CEA tumors and was associated with local accumulation of CD3(+) T cells and CD11b(+) macrophages. The display of antibody fragments on the surface of VNP represents a novel strategy for both targeting CEA-expressing tumors and increasing the immunogenicity of Salmonella-based vaccines for cancer.

  14. Anti-CD47 Antibody As a Targeted Therapeutic Agent for Human Lung Cancer and Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Xiubao Ren

    2017-04-01

    Full Text Available Accumulating evidence indicates that a small subset of cancer cells, termed the tumor-initiating cells or cancer stem cells (CSCs, construct a reservoir of self-sustaining cancer cells with the characteristic ability to self-renew and maintain the tumor mass. The CSCs play an important role in the tumor initiation, development, relapse, metastasis, and the ineffectiveness of conventional cancer therapies. CD47 is a ligand for signal-regulatory protein-α expressed on phagocytic cells and functions to inhibit phagocytosis. This study was to explore if the expression of CD47 is the mechanism used by lung cancer cells, especially CSCs, to escape phagocytosis in vitro and in vivo. Here, we selected CD133 as the marker for lung CSCs according to previous reports. We analyzed lung cancer and matched adjacent normal (non-tumor tissue and revealed that CD47 is overexpressed on lung cancer cells, especially on lung CSCs. The mRNA expression levels of CD47 and CD133 correlated with a decreased probability of survival for multiple types of lung cancer. Blocking CD47 function with anti-CD47 antibodies enabled macrophage phagocytosis of lung cancer cells and lung CSCs. Anti-CD47 antibodies inhibited tumor growth in immunodeficient mouse xenotransplantation models established with lung cancer cells or lung CSCs and improved survival in tumor-bearing animals. These data indicate that CD47 is a valid target for cancer therapies, especially for anti-CSC therapies.

  15. Combination of SDS-PAGE and intact mass analysis for rapid determination of heterogeneities in monoclonal antibody therapeutics.

    Science.gov (United States)

    Yamada, Hideaki; Matsumura, Chiemi; Yamada, Keita; Teshima, Koichiro; Hiroshima, Takashi; Kinoshita, Mitsuhiro; Suzuki, Shigeo; Kakehi, Kazuaki

    2017-05-01

    mAbs are currently mainstream in biopharmaceuticals, and their market has been growing due to their high target specificity. Characterization of heterogeneities in mAbs is performed to secure their quality and safety by physicochemical analyses. However, they require time-consuming task, which often strain the resources of drug development in pharmaceuticals. Rapid and direct method to determine the heterogeneities should be a powerful tool for pharmaceutical analysis. Considering the advantages of electrophoresis and MS, this study addresses the combination of SDS-PAGE and intact mass analysis, which provides direct, rapid, and orthogonal determination of heterogeneities in mAb therapeutics. mAb therapeutics that migrated in SDS-PAGE were recovered from gel by treatment with SDC-containing buffer. Usage of SDC-containing buffer as extraction solvent and ethanol-based staining solution enhanced the recovery of intact IgG from SDS-PAGE gels. Recovery of mAbs reached more than 86% with 0.2% SD. The heterogeneities, especially N-glycan variants in the recovered mAb therapeutics, were clearly determined by intact mass analysis. We believe that the study is important in pharmaceuticals‧ perspective since orthogonal combination of gel electrophoresis and intact mass analysis should be pivotal role for rapid and precise characterization of mAbs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Effects of Prophylactic and Therapeutic Paracetamol Treatment during Vaccination on Hepatitis B Antibody Levels in Adults: Two Open-Label, Randomized Controlled Trials

    Science.gov (United States)

    Doedée, Anne M. C. M.; Boland, Greet J.; Pennings, Jeroen L. A.; de Klerk, Arja; Berbers, Guy A. M.; van der Klis, Fiona R. M.; de Melker, Hester E.; van Loveren, Henk; Janssen, Riny

    2014-01-01

    Worldwide, paracetamol is administered as a remedy for complaints that occur after vaccination. Recently published results indicate that paracetamol inhibits the vaccination response in infants when given prior to vaccination. The goal of this study was to establish whether paracetamol exerts similar effects in young adults. In addition, the effect of timing of paracetamol intake was investigated. In two randomized, controlled, open-label studies 496 healthy young adults were randomly assigned to three groups. The study groups received paracetamol for 24 hours starting at the time of (prophylactic use) - or 6 hours after (therapeutic use) the primary (0 month) and first booster (1 month) hepatitis B vaccination. The control group received no paracetamol. None of the participants used paracetamol around the second booster (6 months) vaccination. Anti-HBs levels were measured prior to and one month after the second booster vaccination on ADVIA Centaur XP. One month after the second booster vaccination, the anti-HBs level in the prophylactic paracetamol group was significantly lower (p = 0.048) than the level in the control group (4257 mIU/mL vs. 5768 mIU/mL). The anti-HBs level in the therapeutic paracetamol group (4958 mIU/mL) was not different (p = 0.34) from the level in the control group. Only prophylactic paracetamol treatment, and not therapeutic treatment, during vaccination has a negative influence on the antibody concentration after hepatitis B vaccination in adults. These findings prompt to consider therapeutic instead of prophylactic treatment to ensure maximal vaccination efficacy and retain the possibility to treat pain and fever after vaccination. Trial Registration Controlled-Trials.com ISRCTN03576945 PMID:24897504

  17. Total Body Irradiation Mitigates Inflammation and Extends the Therapeutic Time Window for Anti-Ricin Antibody Treatment against Pulmonary Ricinosis in Mice

    Directory of Open Access Journals (Sweden)

    Yoav Gal

    2017-09-01

    Full Text Available Ricin, a highly toxic plant-derived toxin, is considered a potential weapon in biowarfare and bioterrorism due to its pronounced toxicity, high availability, and ease of preparation. Pulmonary exposure to ricin results in the generation of an acute edematous inflammation followed by respiratory insufficiency and death. Massive neutrophil recruitment to the lungs may contribute significantly to ricin-mediated morbidity. In this study, total body irradiation (TBI served as a non-pharmacological tool to decrease the potential neutrophil-induced lung injury. TBI significantly postponed the time to death of intranasally ricin-intoxicated mice, given that leukopenia remained stable following intoxication. This increase in time to death coincided with a significant reduction in pro-inflammatory marker levels, and led to marked extension of the therapeutic time window for anti-ricin antibody treatment.

  18. Therapeutic Antibodies Targeting CSF1 Impede Macrophage Recruitment in a Xenograft Model of Tenosynovial Giant Cell Tumor

    Directory of Open Access Journals (Sweden)

    Hongwei Cheng

    2010-01-01

    Full Text Available Tenosynovial giant cell tumor is a neoplastic disease of joints that can cause severe morbidity. Recurrences are common following local therapy, and no effective medical therapy currently exists. Recent work has demonstrated that all cases overexpress macrophage colony-stimulating factor (CSF1, usually as a consequence of an activating gene translocation, resulting in an influx of macrophages that form the bulk of the tumor. New anti-CSF1 drugs have been developed; however there are no preclinical models suitable for evaluation of drug benefits in this disease. In this paper, we describe a novel renal subcapsular xenograft model of tenosynovial giant cell tumor. Using this model, we demonstrate that an anti-CSF1 monoclonal antibody significantly inhibits host macrophage infiltration into this tumor. The results from this model support clinical trials of equivalent humanized agents and anti-CSF1R small molecule drugs in cases of tenosynovial giant cell tumor refractory to conventional local therapy.

  19. Therapeutic mechanism and efficacy of the antibody-drug conjugate BAY 79-4620 targeting human carbonic anhydrase 9.

    Science.gov (United States)

    Petrul, Heike M; Schatz, Christoph A; Kopitz, Charlotte C; Adnane, Lila; McCabe, Timothy J; Trail, Pamela; Ha, Sha; Chang, Yong S; Voznesensky, Andrei; Ranges, Gerald; Tamburini, Paul P

    2012-02-01

    Carbonic anhydrase IX (CAIX) is a cell surface glycoprotein that is expressed in many different tumors and yet restricted in normal tissues to the gastrointestinal tract. It is upregulated by hypoxia and correlates with tumor grade and poor survival in several tumor indications. Monoclonal antibodies (mAb) with single digit nanomolar binding affinity for CAIX were derived by panning with the recombinant ectodomain of CAIX against the MorphoSys HUCAL Gold library of human Fabs. Highest affinity Fabs were converted to full-length IgGs and subjected to further characterization based upon their avidity and selectivity for CAIX, their capacity to undergo internalization in CAIX-expressing cell lines, and their selective localization to CAIX-positive human xenografted tumors when administered to mice as fluorescent conjugates. Through this selection process, the 3ee9 mAb was identified, which upon conjugation to monomethyl auristatin E through a self-immolative enzyme-cleavable linker yielded the potent and selective CAIX antibody-drug conjugate CAIX-ADC (BAY 79-4620). In preclinical human xenograft models in mice representing several tumor indications, BAY 79-4620 showed potent antitumor efficacy and in some models showed partial and complete tumor shrinkage even following a single dose. The mechanism of action was shown by histology to involve the sequelae of events typical of antitubulin agents. Efficacy in murine preclinical models correlated semiquantitatively, with CAIX expression levels as determined by immunohistochemistry and ELISA. These preclinical data collectively support the development of BAY 79-4620 for the treatment of cancer patients with CAIX overexpressing tumors.

  20. Development of a therapeutic monoclonal antibody that targets secreted fatty acid-binding protein aP2 to treat type 2 diabetes.

    Science.gov (United States)

    Burak, M Furkan; Inouye, Karen E; White, Ariel; Lee, Alexandra; Tuncman, Gurol; Calay, Ediz S; Sekiya, Motohiro; Tirosh, Amir; Eguchi, Kosei; Birrane, Gabriel; Lightwood, Daniel; Howells, Louise; Odede, Geofrey; Hailu, Hanna; West, Shauna; Garlish, Rachel; Neale, Helen; Doyle, Carl; Moore, Adrian; Hotamisligil, Gökhan S

    2015-12-23

    The lipid chaperone aP2/FABP4 has been implicated in the pathology of many immunometabolic diseases, including diabetes in humans, but aP2 has not yet been targeted for therapeutic applications. aP2 is not only an intracellular protein but also an active adipokine that contributes to hyperglycemia by promoting hepatic gluconeogenesis and interfering with peripheral insulin action. Serum aP2 levels are markedly elevated in mouse and human obesity and strongly correlate with metabolic complications. These observations raise the possibility of a new strategy to treat metabolic disease by targeting serum aP2 with a monoclonal antibody (mAb) to aP2. We evaluated mAbs to aP2 and identified one, CA33, that lowered fasting blood glucose, improved systemic glucose metabolism, increased systemic insulin sensitivity, and reduced fat mass and liver steatosis in obese mouse models. We examined the structure of the aP2-CA33 complex and resolved the target epitope by crystallographic studies in comparison to another mAb that lacked efficacy in vivo. In hyperinsulinemic-euglycemic clamp studies, we found that the antidiabetic effect of CA33 was predominantly linked to the regulation of hepatic glucose output and peripheral glucose utilization. The antibody had no effect in aP2-deficient mice, demonstrating its target specificity. We conclude that an aP2 mAb-mediated therapeutic constitutes a feasible approach for the treatment of diabetes. Copyright © 2015, American Association for the Advancement of Science.

  1. Anti-LeY antibody enhances therapeutic efficacy of celecoxib against gastric cancer by downregulation of MAPKs/COX-2 signaling pathway: correlation with clinical study.

    Science.gov (United States)

    Aziz, Faisal; Yang, Xuesong; Wang, Xiaoqi; Yan, Qiu

    2015-07-01

    Helicobacter pylori (H. pylori) is a major causative agent for the induction of chronic gastritis, gastric ulcer and gastric cancer. Celecoxib (COX-2 inhibitor) inhibits gastric cancer cell proliferation, but with low treatment efficacy, limiting its applications. It is important to develop a better strategy to improve the efficacy of celecoxib. Lewis Y (LeY) is a difucosylated oligosaccharide, highly expressed in 60-90% of human epithelial cancers, including gastric cancer. We previously found that H. pylori infection was associated with high level of LeY in gastric cancer. Herein, we analyzed the correlation between H. pylori and cyclo-oxygenase-2 (COX-2), LeY, gastric markers (CA724 and GRN) in gastric patient's tissue and serum samples by IHC and ELISA. Furthermore, we treated the primary gastric cancer cells with celecoxib, anti-LeY antibody or the combination, and analyzed their therapeutic efficacy on CA724, GRN and COX-2 expression by Western blot, flow cytometry and ELISA. We found that gastric cancer had significantly high expression of H. pylori, COX-2, CA724, and GRN compared to gastric ulcers and chronic gastritis (P LeY (R--0.861), CA724 (R--0.714) and GRN (R--0.664) (P LeY antibody enhances the cancer cell proliferation inhibitory effects of celecoxib, which might be a new feasible way for gastric cancer therapy.

  2. New blocking antibodies impede adhesion, migration and survival of ovarian cancer cells, highlighting MFGE8 as a potential therapeutic target of human ovarian carcinoma.

    Directory of Open Access Journals (Sweden)

    Lorenzo Tibaldi

    Full Text Available Milk Fat Globule--EGF--factor VIII (MFGE8, also called lactadherin, is a secreted protein, which binds extracellularly to phosphatidylserine and to αvβ3 and αvβ5 integrins. On human and mouse cells expressing these integrins, such as endothelial cells, phagocytes and some tumors, MFGE8/lactadherin has been shown to promote survival, epithelial to mesenchymal transition and phagocytosis. A protumoral function of MFGE8 has consequently been documented for a few types of human cancers, including melanoma, a subtype of breast cancers, and bladder carcinoma. Inhibiting the functions of MFGE8 could thus represent a new type of therapy for human cancers. Here, we show by immunohistochemistry on a collection of human ovarian cancers that MFGE8 is overexpressed in 45% of these tumors, and we confirm that it is specifically overexpressed in the triple-negative subtype of human breast cancers. We have established new in vitro assays to measure the effect of MFGE8 on survival, adhesion and migration of human ovarian and triple-negative breast cancer cell lines. Using these assays, we could identify new MFGE8-specific monoclonal antibodies, which efficiently blocked these three tumor-promoting effects of MFGE8. Our results suggest future use of MFGE8-blocking antibodies as new anti-cancer therapeutics in subgroups of ovarian carcinoma, and triple-negative breast carcinoma patients.

  3. Therapeutic Effects of Monoclonal Antibody against Dengue Virus NS1 in a STAT1 Knockout Mouse Model of Dengue Infection.

    Science.gov (United States)

    Wan, Shu-Wen; Chen, Pei-Wei; Chen, Chin-Yu; Lai, Yen-Chung; Chu, Ya-Ting; Hung, Chia-Yi; Lee, Han; Wu, Hsuan Franziska; Chuang, Yung-Chun; Lin, Jessica; Chang, Chih-Peng; Wang, Shuying; Liu, Ching-Chuan; Ho, Tzong-Shiann; Lin, Chiou-Feng; Lee, Chien-Kuo; Wu-Hsieh, Betty A; Anderson, Robert; Yeh, Trai-Ming; Lin, Yee-Shin

    2017-10-15

    Dengue virus (DENV) is the causative agent of dengue fever, dengue hemorrhagic fever, and dengue shock syndrome and is endemic to tropical and subtropical regions of the world. Our previous studies showed the existence of epitopes in the C-terminal region of DENV nonstructural protein 1 (NS1) which are cross-reactive with host Ags and trigger anti-DENV NS1 Ab-mediated endothelial cell damage and platelet dysfunction. To circumvent these potentially harmful events, we replaced the C-terminal region of DENV NS1 with the corresponding region from Japanese encephalitis virus NS1 to create chimeric DJ NS1 protein. Passive immunization of DENV-infected mice with polyclonal anti-DJ NS1 Abs reduced viral Ag expression at skin inoculation sites and shortened DENV-induced prolonged bleeding time. We also investigated the therapeutic effects of anti-NS1 mAb. One mAb designated 2E8 does not recognize the C-terminal region of DENV NS1 in which host-cross-reactive epitopes reside. Moreover, mAb 2E8 recognizes NS1 of all four DENV serotypes. We also found that mAb 2E8 caused complement-mediated lysis in DENV-infected cells. In mouse model studies, treatment with mAb 2E8 shortened DENV-induced prolonged bleeding time and reduced viral Ag expression in the skin. Importantly, mAb 2E8 provided therapeutic effects against all four serotypes of DENV. We further found that mAb administration to mice as late as 1 d prior to severe bleeding still reduced prolonged bleeding time and hemorrhage. Therefore, administration with a single dose of mAb 2E8 can protect mice against DENV infection and pathological effects, suggesting that NS1-specific mAb may be a therapeutic option against dengue disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  4. Prophylactic and therapeutic testing of Nicotiana-derived RSV-neutralizing human monoclonal antibodies in the cotton rat model.

    Science.gov (United States)

    Zeitlin, Larry; Bohorov, Ognian; Bohorova, Natasha; Hiatt, Andrew; Kim, Do H; Pauly, Michael H; Velasco, Jesus; Whaley, Kevin J; Barnard, Dale L; Bates, John T; Crowe, James E; Piedra, Pedro A; Gilbert, Brian E

    2013-01-01

    Severe lower respiratory tract infection in infants and small children is commonly caused by respiratory syncytial virus (RSV). Palivizumab (Synagis(®)), a humanized IgG1 monoclonal antibody (mAb) approved for RSV immunoprophylaxis in at-risk neonates, is highly effective, but pharmacoeconomic analyses suggest its use may not be cost-effective. Previously described potent RSV neutralizers (human Fab R19 and F2-5; human IgG RF-1 and RF-2) were produced in IgG format in a rapid and inexpensive Nicotiana-based manufacturing system for comparison with palivizumab. Both plant-derived (palivizumab-N) and commercial palivizumab, which is produced in a mouse myeloma cell line, showed protection in prophylactic (p plant-derived human mAbs directed against alternative epitopes displayed neutralizing activity, but conferred less protection in vivo than palivizumab-N or palivizumab. Palivizumab remains one of the most efficacious RSV mAbs described to date. Production in plants may reduce manufacturing costs and improve the pharmacoeconomics of RSV immunoprophylaxis and therapy.

  5. Evaluation of the therapeutic efficacy of a VEGFR2-blocking antibody using sodium-iodide symporter molecular imaging in a tumor xenograft model

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Su-Jin; Lee, Chang-Moon; Kim, Eun-Mi [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Uhm, Tai-Boong [Faculty of Biological Science, Chonbuk National University, Jeonju-si, jeonbuk 561-756 (Korea, Republic of); Jeong, Hwan-Jeong, E-mail: jayjeong@chonbuk.ac.k [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Kim, Dong Wook; Lim, Seok Tae; Sohn, Myung-Hee [Department of Nuclear Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of); Cyclotron Research Center, Chonbuk National University Hospital, Jeonju-si, Jeonbuk 561-712 (Korea, Republic of)

    2011-01-15

    Purpose: Vascular endothelial growth factor receptor 2-blocking antibody (DC101) has inhibitory effects on tumor growth and angiogenesis in vivo. The human sodium/iodide symporter (hNIS) gene has been shown to be a useful molecular imaging reporter gene. Here, we investigated the evaluation of therapeutic efficacy by molecular imaging in reporter gene transfected tumor xenografts using a gamma imaging system. Methods: The hNIS gene was transfected into MDA-MB-231 cells using Lipofectamine. The correlation between the number of MDA-MB-231-hNIS cells and the uptake of {sup 99m}Tc-pertechnetate or {sup 125}I was investigated in vitro by gamma imaging and counting. MDA-MB-231-hNIS cells were injected subcutaneously into mice. When the tumor volume reached 180-200 mm{sup 3}, we randomly assigned five animals to each of three groups representing different tumor therapies; no DC101 (control), 100 {mu}g, or 150 {mu}g DC101/mouse. One week and 2 weeks after the first injection of DC101, gamma imaging was performed. Mice were sacrificed 2 weeks after the first injection of DC101. The tumor tissues were used for reverse transcriptase-polymerase chain reaction (RT-PCR) and CD31 staining. Results: Uptake of {sup 125}I and {sup 99m}Tc-pertechnetate into MDA-MB-231-hNIS cells in vitro showed correlation with the number of cells. In DC101 treatment groups, the mean tumor volume was smaller than that of the control mice. Furthermore, tumor uptake of {sup 125}I was lower than in the controls. The CD31 staining and RT-PCR assay results showed that vessel formation and expression of the hNIS gene were significantly reduced in the tumor tissues of treatment groups. Conclusion: This study demonstrated the power of molecular imaging using a gamma imaging system for evaluating the therapeutic efficacy of an antitumor treatment. Molecular imaging systems may be useful in evaluation and development of effective diagnostic and/or therapeutic antibodies for specific target molecules.

  6. Different adaptations of IgG effector function in human and nonhuman primates and implications for therapeutic antibody treatment.

    Science.gov (United States)

    Warncke, Max; Calzascia, Thomas; Coulot, Michele; Balke, Nicole; Touil, Ratiba; Kolbinger, Frank; Heusser, Christoph

    2012-05-01

    Safety of human therapeutic Abs is generally assessed in nonhuman primates. Whereas IgG1 shows identical FcγR interaction and effector function profile in both species, fundamental differences in the IgG2 and IgG4 Ab subclasses were found between the two species. Granulocytes, the main effector cells against IgG2- and IgG4-opsonized bacteria and parasites, do not express FcγRIIIb, but show higher levels of FcγRII in cynomolgus monkey. In humans, IgG2 and IgG4 adapted a silent Fc region with weak binding to FcγR and effector functions, whereas, in contrast, cynomolgus monkey IgG2 and IgG4 display strong effector function as well as differences in IgG4 Fab arm exchange. To balance this shift toward activation, the cynomolgus inhibitory FcγRIIb shows strongly increased affinity for IgG2. In view of these findings, in vitro and in vivo results for human IgG2 and IgG4 obtained in the cynomolgus monkey have to be cautiously interpreted, whereas effector function-related effects of human IgG1 Abs are expected to be predictable for humans.

  7. Therapeutic anti-IgE monoclonal antibody single chain variable fragment (scFv) safety and immunomodulatory effects after one time injection in four dogs.

    Science.gov (United States)

    Hammerberg, Bruce; Eguiluz-Hernandez, Sitka

    2017-02-01

    The therapeutic monoclonal antibody omalizumab that is specific for IgE has proven to be an effective addition to the treatment of allergic disease in humans. The aims of this study were to demonstrate the safety and immunomodulating effects of a single injection of a monoclonal antibody single chain variable fragments (scFv) specific for canine IgE in normal dogs. Three normal dogs were bled for EDTA whole blood samples for 112 days post-injection (dpi). A fourth dog was monitored for 28 days. Anti-IgE scFv was pegylated to minimize scFv dimerization. Four normal dogs were injected once subcutaneously with anti-IgE scFv at 1 mg/kg. Flow cytometry was performed on whole blood. Plasma levels of IgE were measured by ELISA. None of the four dogs showed signs of anaphylaxis. All dogs demonstrated decreases in IgE(+) cells in lymphocyte-gated events by 14 dpi. Dogs C and D returned to pre-injection levels by 21 days, whereas dogs A and B remained below pre-injection levels until Day 112. Similar differences were seen in IgE-bearing granulocyte-gated cells. Free plasma IgE decreased below pre-injection levels by 47% in Dog A and by 52% in Dog B at 112 days. Dogs C and D did not change by more than 32% from preinjection levels. A single injection of monomeric, pegylated scFv with high affinity for dog IgE was demonstrated to be safe. Marked reduction in IgE-bearing lymphocytes and granulocytes accompanied by reduced "free" plasma IgE level in two of four dogs is analogous to omalizumab in humans. © 2016 ESVD and ACVD.

  8. Therapeutic effects of anti-CD115 monoclonal antibody in mouse cancer models through dual inhibition of tumor-associated macrophages and osteoclasts.

    Directory of Open Access Journals (Sweden)

    Laetitia Fend

    Full Text Available Tumor progression is promoted by Tumor-Associated Macrophages (TAMs and metastasis-induced bone destruction by osteoclasts. Both myeloid cell types depend on the CD115-CSF-1 pathway for their differentiation and function. We used 3 different mouse cancer models to study the effects of targeting cancer host myeloid cells with a monoclonal antibody (mAb capable of blocking CSF-1 binding to murine CD115. In mice bearing sub-cutaneous EL4 tumors, which are CD115-negative, the anti-CD115 mAb depleted F4/80(+ CD163(+ M2-type TAMs and reduced tumor growth, resulting in prolonged survival. In the MMTV-PyMT mouse model, the spontaneous appearance of palpable mammary tumors was delayed when the anti-CD115 mAb was administered before malignant transition and tumors became palpable only after termination of the immunotherapy. When administered to mice already bearing established PyMT tumors, anti-CD115 treatment prolonged their survival and potentiated the effect of chemotherapy with Paclitaxel. As shown by immunohistochemistry, this therapeutic effect correlated with the depletion of F4/80(+CD163(+ M2-polarized TAMs. In a breast cancer model of bone metastasis, the anti-CD115 mAb potently blocked the differentiation of osteoclasts and their bone destruction activity. This resulted in the inhibition of cancer-induced weight loss. CD115 thus represents a promising target for cancer immunotherapy, since a specific blocking antibody may not only inhibit the growth of a primary tumor through TAM depletion, but also metastasis-induced bone destruction through osteoclast inhibition.

  9. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  10. Formulation development of therapeutic monoclonal antibodies using high-throughput fluorescence and static light scattering techniques: role of conformational and colloidal stability.

    Science.gov (United States)

    Goldberg, Deborah S; Bishop, Steven M; Shah, Ambarish U; Sathish, Hasige A

    2011-04-01

    In this work, we describe the application of two different high-throughput screening (HTS) techniques that can be used to determine protein stability during early formulation development. Differential scanning fluorescence (DSF) and differential static light scattering (DSLS) are used to determine the conformational and colloidal stability of therapeutic monoclonal antibodies (mAbs) during thermal denaturation in a high-throughput fashion. DSF utilizes SYPRO Orange, a polarity-sensitive extrinsic fluorescent probe, to monitor protein unfolding. We found that melting temperatures determined by DSF have a linear correlation with melting temperatures of the first domain unfolding determined by differential scanning calorimetry, establishing DSF as a reliable method for measuring thermal stability. The DSLS method employs static light scattering to evaluate protein stability during thermal denaturation in a 384-well format. Overall comparison between mAb aggregation under typical accelerated stress conditions (40°C) and the thermal stability obtained by DSF and DSLS is also presented. Both of these HTS methods are cost effective with high-throughput capability and can be implemented in any laboratory. Combined with other emerging HTS techniques, DSF and DSLS could be powerful tools for mAb formulation optimization. Copyright © 2010 Wiley-Liss, Inc.

  11. The future of monoclonal antibody technology

    OpenAIRE

    Zider, Alexander; Drakeman, Donald L

    2010-01-01

    With the rapid growth of monoclonal antibody-based products, new technologies have emerged for creating modified forms of antibodies, including fragments, conjugates and multi-specific antibodies. We created a database of 450 therapeutic antibodies in development to determine which technologies and indications will constitute the “next generation” of antibody products. We conclude that the antibodies of the future will closely resemble the antibodies that have already been approved for commer...

  12. Expression of recombinant Antibodies

    Directory of Open Access Journals (Sweden)

    André eFrenzel

    2013-07-01

    Full Text Available Recombinant antibodies are highly specific detection probes in research, diagnostics and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines and transgenic plants are promising to obtain antibodies with human-like post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications.

  13. Expression of Recombinant Antibodies

    Science.gov (United States)

    Frenzel, André; Hust, Michael; Schirrmann, Thomas

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines, and transgenic plants are promising to obtain antibodies with “human-like” post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications. PMID:23908655

  14. Antibodies and Selection of Monoclonal Antibodies.

    Science.gov (United States)

    Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

    Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

  15. Human monoclonal antibodies: the residual challenge of antibody immunogenicity.

    Science.gov (United States)

    Waldmann, Herman

    2014-01-01

    One of the major reasons for seeking human monoclonal antibodies has been to eliminate immunogenicity seen with rodent antibodies. Thus far, there has yet been no approach which absolutely abolishes that risk for cell-binding antibodies. In this short article, I draw attention to classical work which shows that monomeric immunoglobulins are intrinsically tolerogenic if they can be prevented from creating aggregates or immune complexes. Based on these classical studies two approaches for active tolerization to therapeutic antibodies are described.

  16. Expression of Recombinant Antibodies

    OpenAIRE

    André eFrenzel; Michael eHust; Thomas eSchirrmann

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transg...

  17. Antimitochondrial antibody

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003529.htm Antimitochondrial antibody To use the sharing features on this page, please enable JavaScript. Antimitochondrial antibodies (AMA) are substances ( antibodies ) that form against mitochondria. ...

  18. Therapeutic IMC-C225 antibody inhibits breast cancer cell invasiveness via Vav2-dependent activation of RhoA GTPase.

    Science.gov (United States)

    Molli, Poonam R; Adam, Liana; Kumar, Rakesh

    2008-10-01

    Abnormalities in the expression and signaling pathways downstream of epidermal growth factor receptor (EGFR) contribute to progression, invasion, and maintenance of the malignant phenotype in human cancers. Accordingly, biological agents, such as the EGFR-blocking antibody IMC-C225 have promising anticancer potential and are currently in various stages of clinical development. Because use of IMC-C225 is limited, at present, only for treatment of cancer with high EGFR expression, the goal of the present study was to determine the effect of IMC-C225 on the invasiveness of breast cancer cells with high and low levels of EGFR expression. The effect of IMC-C225 on invasion was studied using breast cancer cell lines with high and low levels of EGFR expression. The addition of EGF led to progressive stress fiber dissolution. In contrast, cells treated with IMC-C225 showed reduced invasiveness and increased stress-fiber formation. Interestingly, IMC-C225 pretreatment was accompanied by EGFR phosphorylation, as detected using an anti-phosphorylated tyrosine antibody (PY99), which correlated with phosphorylation of Vav2 guanine nucleotide exchange factor and activation of RhoA GTPase irrespective of EGFR level, and Vav2 interacted with EGFR only in IMC-C225-treated cells. The underlying mechanism involved an enhanced interaction between beta1 integrins and EGFR upon IMC-C225 treatment. Here, we defined a new mechanism for IMC-C225 that cross-links integrins with EGFR, leading to activation of RhoA and inhibition of breast cancer cell invasion irrespective of the level of EGFR in the cells, thus providing a rationale for using IMC-C225 in the metastatic setting independent of the levels of EGFR.

  19. Complete Removal of Extracellular IgG Antibodies in a Randomized Dose-Escalation Phase I Study with the Bacterial Enzyme IdeS – A Novel Therapeutic Opportunity

    Science.gov (United States)

    Winstedt, Lena; Järnum, Sofia; Nordahl, Emma Andersson; Olsson, Andreas; Runström, Anna; Bockermann, Robert; Karlsson, Christofer; Malmström, Johan; Palmgren, Gabriella Samuelsson; Malmqvist, Ulf; Björck, Lars; Kjellman, Christian

    2015-01-01

    IdeS is a streptococcal protease that cleaves IgG antibodies into F(ab’)2 and Fc fragments with a unique degree of specificity, thereby providing a novel treatment opportunity of IgG-driven autoimmune conditions and antibody mediated transplant rejection. Here we report the results from a first in man, double blinded and randomized study with single ascending doses of IdeS in healthy, male subjects. Twenty healthy subjects were given intravenous single ascending doses of IdeS. With impressive efficacy IdeS cleaved the entire plasma IgG-pool only minutes after dosing. IgG reached nadir 6-24 hours after dosing and then slowly recovered. The half-life of IdeS was 4.9 (±2.8) hours at 0.24 mg/kg with the main fraction eliminated during 24 hours. Already two hours after IdeS-dosing, the phagocytic capacity of IgG/IgG-fragments was reduced to background levels. Importantly, IdeS has the capacity to inactivate Fc-mediated effector function in vivo, was considered safe with no serious adverse events, and without dose limiting toxicity in this study. The complete, rapid, but temporary removal of IgG provides a new potent therapeutic opportunity in IgG-mediated pathogenic conditions. Trial Registration ClinicalTrials.gov NCT01802697 PMID:26177518

  20. The Effects of Light-Accelerated Degradation on the Aggregation of Marketed Therapeutic Monoclonal Antibodies Evaluated by Size-Exclusion Chromatography With Diode Array Detection.

    Science.gov (United States)

    Hernández-Jiménez, José; Salmerón-García, Antonio; Cabeza, José; Vélez, Celia; Capitán-Vallvey, Luis Fermín; Navas, Natalia

    2016-04-01

    Research into the effects that exposure to light can have on therapeutic proteins is essential for ensuring the quality and safety of the medicines in which they are used. It is important to understand the effects of light on aggregation to help avoid undesirable colloidal instabilities, both in the original medicines and in the formats in which they are finally administered. In this study, 5 marketed therapeutic mAbs, namely bevacizumab, cetuximab, infliximab, rituximab, and trastuzumab, were investigated for this purpose. The medicines and 2 diluted preparations in 0.9 NaCl (2 mg/mL and 5 mg/mL)-commonly used in clinical practice-were subjected to controlled light-accelerated degradation. The formation of aggregates was monitored by size-exclusion chromatography. The results indicated that light induced protein aggregation. This process of protein damage was influenced above all by mAb concentration, although the particular characteristics of each mAb were also important. Photodegradation also produced the fragmentation of the mAbs. The damage caused to the mAbs as a result of light-induced aggregation and/or fragmentation was demonstrated both in the medicines and in the diluted preparation forms. These findings should be carefully considered when handling the medicines for administration and when recommending beyond-use dates in normal hospital conditions. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  1. A truncated receptor-binding domain of MERS-CoV spike protein potently inhibits MERS-CoV infection and induces strong neutralizing antibody responses: implication for developing therapeutics and vaccines.

    Directory of Open Access Journals (Sweden)

    Lanying Du

    Full Text Available An emerging respiratory infectious disease with high mortality, Middle East respiratory syndrome (MERS, is caused by a novel coronavirus (MERS-CoV. It was first reported in 2012 in Saudi Arabia and has now spread to eight countries. Development of effective therapeutics and vaccines is crucial to save lives and halt the spread of MERS-CoV. Here, we show that a recombinant protein containing a 212-amino acid fragment (residues 377-588 in the truncated receptor-binding domain (RBD: residues 367-606 of MERS-CoV spike (S protein fused with human IgG Fc fragment (S377-588-Fc is highly expressed in the culture supernatant of transfected 293T cells. The purified S377-588-Fc protein efficiently binds to dipeptidyl peptidase 4 (DPP4, the receptor of MERS-CoV, and potently inhibited MERS-CoV infection, suggesting its potential to be further developed as a therapeutic modality for treating MERS-CoV infection and saving the patients' lives. The recombinant S377-588-Fc is able to induce in the vaccinated mice strong MERS-CoV S-specific antibodies, which blocks the binding of RBD to DPP4 receptor and effectively neutralizes MERS-CoV infection. These findings indicate that this truncated RBD protein shows promise for further development as an effective and safe vaccine for the prevention of MERS-CoV infection.

  2. Therapeutic vaccine using a monoclonal antibody against a 70-kDa glycoprotein in mice infected with highly virulent Sporothrix schenckii and Sporothrix brasiliensis.

    Science.gov (United States)

    de Almeida, José Roberto Fogaça; Kaihami, Gilberto Hideo; Jannuzzi, Grasielle Pereira; de Almeida, Sandro Rogerio

    2015-01-01

    Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungi that comprise the Sporothrix complex. The latter are widely distributed in nature, developing a saprophytic mycelial form on plant debris and soil. Formerly, the S. schenckii species was thought to be the only species capable of causing sporotrichosis. However, in recent years, the existence of a group of highly genotypically and phenotypically variable species has been reported as etiologic agents of this mycosis. Recently, it has become important to study aspects such as virulence and the immune response against key members of the Sporothrix complex and to observe the presence of glycoprotein (gp) 70 and efficacy of the P6E7 monoclonal antibody against more virulent strains. The data presented here demonstrate that the strain isolated from a case of feline sporotrichosis, that is, strain 5110 (American Type Culture Collection MYA-4823) is the most virulent and the only one able to secrete gp70. This glycoprotein is apparently an important factor in the virulence of Sporothrix spp. because treatment with MAb P6E7 resulted in the reduction of fungal burden in the analyzed organs. Additional studies of the role of gp70 in modulating the immune response of the host are needed to understand the pathology of sporotrichosis. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Quantitative analysis of the CD4+ T cell response to therapeutic antibodies in healthy donors using a novel T cell:PBMC assay.

    Science.gov (United States)

    Schultz, Heidi S; Reedtz-Runge, Stine Louise; Bäckström, B Thomas; Lamberth, Kasper; Pedersen, Christian R; Kvarnhammar, Anne M

    2017-01-01

    Many biopharmaceuticals (BPs) are known to be immunogenic in the clinic, which can result in modified pharmacokinetics, reduced efficacy, allergic reactions and anaphylaxis. During recent years, several technologies to predict immunogenicity have been introduced, but the predictive value is still considered low. Thus, there is an unmet medical need for optimization of such technologies. The generation of T cell dependent high affinity anti-drug antibodies plays a key role in clinical immunogenicity. This study aimed at developing and evaluating a novel in vitro T cell:PBMC assay for prediction of the immunogenicity potential of BPs. To this end, we assessed the ability of infliximab (anti-TNF-α), rituximab (anti-CD20), adalimumab (anti-TNF-α) and natalizumab (anti-α4-integrin), all showing immunogenicity in the clinic, to induce a CD4+ T cells response. Keyhole limpet hemocyanin (KLH) and cytomegalovirus pp65 protein (CMV) were included as neo-antigen and recall antigen positive controls, respectively. By analyzing 26 healthy donors having HLA-DRB1 alleles matching the European population, we calculated the frequency of responding donors, the magnitude of the response, and the frequency of BP-specific T cells, as measured by 3[H]-thymidine incorporation and ELISpot IL-2 secretion. KLH and CMV demonstrated a strong T cell response in all the donors analyzed. The frequency of responding donors to the BPs was 4% for infliximab, 8% for adalimumab, 19% for rituximab and 27% for natalizumab, which is compared to and discussed with their respective observed clinical immunogenicity. This study further complements predictive immunogenicity testing by quantifying the in vitro CD4+ T cell responses to different BPs. Even though the data generated using this modified method does not directly translate to the clinical situation, a high sensitivity and immunogenic potential of most BPs is demonstrated.

  4. r84, a novel therapeutic antibody against mouse and human VEGF with potent anti-tumor activity and limited toxicity induction.

    Directory of Open Access Journals (Sweden)

    Laura A Sullivan

    2010-08-01

    Full Text Available Vascular endothelial growth factor (VEGF is critical for physiological and pathological angiogenesis. Within the tumor microenvironment, VEGF functions as an endothelial cell survival factor, permeability factor, mitogen, and chemotactic agent. The majority of these functions are mediated by VEGF-induced activation of VEGF receptor 2 (VEGFR2, a high affinity receptor tyrosine kinase expressed by endothelial cells and other cell types in the tumor microenvironment. VEGF can also ligate other cell surface receptors including VEGFR1 and neuropilin-1 and -2. However, the importance of VEGF-induced activation of these receptors in tumorigenesis is still unclear. We report the development and characterization of r84, a fully human monoclonal antibody that binds human and mouse VEGF and selectively blocks VEGF from interacting with VEGFR2 but does not interfere with VEGF:VEGFR1 interaction. Selective blockade of VEGF binding to VEGFR2 by r84 is shown through ELISA, receptor binding assays, receptor activation assays, and cell-based functional assays. Furthermore, we show that r84 has potent anti-tumor activity and does not alter tissue histology or blood and urine chemistry after chronic high dose therapy in mice. In addition, chronic r84 therapy does not induce elevated blood pressure levels in some models. The ability of r84 to specifically block VEGF:VEGFR2 binding provides a valuable tool for the characterization of VEGF receptor pathway activation during tumor progression and highlights the utility and safety of selective blockade of VEGF-induced VEGFR2 signaling in tumors.

  5. Therapeutic effects of antigen affinity-purified polyclonal anti-receptor of advanced glycation end-product (RAGE) antibodies on cholestasis-induced liver injury in rats.

    Science.gov (United States)

    Xia, Peng; Deng, Qing; Gao, Jin; Yu, Xiaolan; Zhang, Yang; Li, Jingjing; Guan, Wen; Hu, Jianjun; Tan, Quanhui; Zhou, Liang; Han, Wei; Yuan, Yunsheng; Yu, Yan

    2016-05-15

    Cholestasis leads to acute hepatic injury, fibrosis/cirrhosis, inflammation, and duct proliferation. We investigated whether blocking receptor of advanced glycation end-products (RAGE) with polyclonal anti-RAGE antibodies (anti-RAGE) could regulate acute liver injury and fibrosis in a rat bile duct ligation (BDL) model. Male Wister rats received 0.5mg/kg rabbit anti-RAGE or an equal amount of rabbit IgG by subcutaneous injection twice a week after BDL. Samples of liver tissue and peripheral blood were collected at 14 days after BDL. Serum biochemistry and histology were used to analyze the degree of liver injury. Quantitative real-time PCR (qPCR) and immunohistochemical staining were used to further analyze liver injury. Anti-RAGE improved the gross appearance of the liver and the rat survival rate. Liver tissue histology and relevant serum biochemistry indicated that anti-RAGE attenuated liver necrosis, inflammation, liver fibrosis, and duct proliferation in the BDL model. qPCR and western blotting showed significant reductions in interleukin-1β expression levels in the liver by treatment with anti-RAGE. Anti-RAGE also significantly reduced the mRNA levels of α1(1) collagen (Col1α1) and cholesterol 7α-hydroxylase, and the ratio of tissue inhibitor of matrix metalloproteinase-1 to matrix metalloproteinases (MMPs) in the liver. In addition, anti-RAGE regulated the transcriptional level of Col1α1 and MMP-9 in transforming growth factor-β-induced activated LX-2 cells in vitro. Anti-RAGE was found to inhibit hepatic stellate cell proliferation in vivo and in vitro. Therefore, anti-RAGE can protect the liver from injury induced by BDL in rats. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Production of antibodies and antibody fragments in plants.

    Science.gov (United States)

    Peeters, K; De Wilde, C; De Jaeger, G; Angenon, G; Depicker, A

    2001-03-21

    Our current knowledge allows the generation of transgenic plants that efficiently produce heterologous proteins from plant, bacterial, fungal or animal origin. Among all types of recombinant proteins, antibodies are particularly attractive because of their ability to specifically recognize and bind virtually any type of antigen. Plants show several advantages as a large-scale antibody production system: they can be grown easily and inexpensively in large quantities that can be harvested, stored and processed by using existing infrastructures. Isolation and purification of plant-made antibodies, if necessary, allow fundamental, industrial, and therapeutical applications. In the past, we and others have successfully generated antibody-producing plants. The maximal accumulation levels of antibodies and antibody fragments that we observed are 1-5% of the extracted proteins. Currently, several biotechnological companies grow field crops to produce antibodies for ex planta applications on an industrial scale.

  7. The role of more than 40 years of improvement in protein A chromatography in the growth of the therapeutic antibody industry.

    Science.gov (United States)

    Bolton, Glen R; Mehta, Krunal K

    2016-09-01

    Protein A chromatography has been used as the mAb capture step in the majority of FDA submissions. In this study, the performance of protein A chromatography, as indicated by capacity, operational flow rate, and productivity (rate of mAb production per liter of resin) was examined over its full history to gain insights into the reasons for its consistent use. Protein A productivity and capacity have increased 4.3 and 5.5% a year, respectively, since 1978. In contrast, protein A operational flow rate increased between 1978 and 2001 and then remained constant or declined as further improvements provided only marginal benefits. The productivity of protein A resin and also the mAb bioreactor titer (14% growth) rapidly improved starting in about 1990 to economically provide material for clinical trials. Technology improvement is typically driven by product sales. The sales of protein A resin, as indicated by sales of protein A ligand (21% growth), have closely paralleled the sales of mAbs (20% growth). Both increased rapidly in 2000 after the first major mAb therapeutics were approved and the markets were developed. It is likely that alternatives to protein A chromatography have not been implemented because of the order of magnitude improvement in protein A performance. Protein A membrane adsorbers and monoliths have higher productivity than packed columns due to their short bed heights and high operational flow rates. These devices are not currently practical for large-scale manufacturing but may represent a format for future improvements in protein A productivity. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1193-1202, 2016. © 2016 American Institute of Chemical Engineers.

  8. Identification of a new epitope in uPAR as a target for the cancer therapeutic monoclonal antibody ATN-658, a structural homolog of the uPAR binding integrin CD11b (αM.

    Directory of Open Access Journals (Sweden)

    Xiang Xu

    Full Text Available The urokinase plasminogen activator receptor (uPAR plays a role in tumor progression and has been proposed as a target for the treatment of cancer. We recently described the development of a novel humanized monoclonal antibody that targets uPAR and has anti-tumor activity in multiple xenograft animal tumor models. This antibody, ATN-658, does not inhibit ligand binding (i.e. uPA and vitronectin to uPAR and its mechanism of action remains unclear. As a first step in understanding the anti-tumor activity of ATN-658, we set out to identify the epitope on uPAR to which ATN-658 binds. Guided by comparisons between primate and human uPAR, epitope mapping studies were performed using several orthogonal techniques. Systematic site directed and alanine scanning mutagenesis identified the region of aa 268-275 of uPAR as the epitope for ATN-658. No known function has previously been attributed to this epitope Structural insights into epitope recognition were obtained from structural studies of the Fab fragment of ATN-658 bound to uPAR. The structure shows that the ATN-658 binds to the DIII domain of uPAR, close to the C-terminus of the receptor, corroborating the epitope mapping results. Intriguingly, when bound to uPAR, the complementarity determining region (CDR regions of ATN-658 closely mimic the binding regions of the integrin CD11b (αM, a previously identified uPAR ligand thought to be involved in leukocyte rolling, migration and complement fixation with no known role in tumor progression of solid tumors. These studies reveal a new functional epitope on uPAR involved in tumor progression and demonstrate a previously unrecognized strategy for the therapeutic targeting of uPAR.

  9. A comparison of targetting of neuroblastoma with MIBG and anti L1-CAM antibody mAb chCE7: therapeutic efficacy in a neuroblastoma xenograft model and imaging of neuroblastoma patients

    Energy Technology Data Exchange (ETDEWEB)

    Hoefnagel, C.A. [Dept. of Nuclear Medicine, Netherlands Cancer Institute, Amsterdam (Netherlands); Rutgers, M.; Buitenhuis, C.K.M.; Smets, L.A. [Dept. of Experimental Therapy, Netherlands Cancer Institute, Amsterdam (Netherlands); Kraker, J. de [Academic Medical Center, University of Amsterdam (Netherlands); Meli, M.; Carrel, F.; Schubiger, P.A.; Novak-Hofer, I. [Center for Radiopharmaceutical Science, Paul Scherrer Institute, Villigen (Switzerland); Amstutz, H. [ZLB Bioplasma AG, Berne (Switzerland)

    2001-03-01

    Modine-131 labelled anti L1-CAM antibody mAb chCE7 was compared with the effective neuroblastoma-seeking agent {sup 131}I-labelled metaiodobenzylguanidine (MIBG) with regard to (a) its therapeutic efficacy in treating nude mice with neuroblastoma xenografts and (b) its tumour targetting ability in neuroblastoma patients. The SK-N-SH tumour cells used in the mouse experiments show good MIBG uptake and provide a relatively low number of 6,300 binding sites/cell for mAb chCE7. Tumours were treated with single injections of {sup 131}I-MIBG (110 MBq) and with {sup 131}I-labelled mAb chCE7 (17 MBq) and both agents showed antitumour activity. After therapy with {sup 131}I-chCE7, the subcutaneous tumours nearly disappeared; treatment with {sup 131}I-MIBG was somewhat less effective, resulting in a 70% reduction in tumour volume. A calculated tumour regrowth delay of 9 days occurred with a radioactivity dose of 17 MBq of an irrelevant control antibody mAb 35, which does not bind to SK-N-SH cells, compared with a regrowth delay of 34 days with {sup 131}I-mAb chCE7 and of 24 days with {sup 131}I-MIBG. General toxicity appeared to be mild, as assessed by a transient, approximate 10% maximum decrease in body weight during the treatments. The superior growth inhibition achieved by {sup 131}I-chCE7 compared with {sup 131}I-MIBG can be explained by its prolonged retention in the tumours, due to slower normal tissue and plasma clearance. Cross-reaction of mAb chCE7 with L1-CAM present in normal human tissues was investigated by direct binding of radioiodinated mAb to frozen tissue sections. Results showed a strong reaction with normal human brain tissue and weak but detectable binding to normal adult kidney sections. Seven patients with recurrent neuroblastoma were sequentially imaged with {sup 131}I-MIBG and {sup 131}I-chCE7. The results underlined the heterogeneity of neuroblastoma and showed the two imaging modalities to be complementary. {sup 131}I-chCE7 scintigraphy may have

  10. Monoclonal Antibodies.

    Science.gov (United States)

    Killington, R. A.; Powell, K. L.

    1984-01-01

    Monoclonal antibodies have provided an exciting addition to the "armory" of the molecular biologist and immunologist. This article discusses briefly the concept of, techniques available for, production of, and possible uses of monoclonal antibodies. (Author)

  11. Thyroid Antibodies

    Science.gov (United States)

    ... Fungal Infections Gout Graves Disease Guillain-Barré Syndrome Hashimoto Thyroiditis Heart Attack and Acute Coronary Syndrome Heart ... hypothyroidism or hyperthyroidism , such as Graves disease or Hashimoto thyroiditis . Thyroid antibody tests include: Thyroid peroxidase antibody ( ...

  12. Innovations in diagnosis and post-therapeutic monitoring of Chagas disease: Simultaneous flow cytometric detection of IgG1 antibodies anti-live amastigote, anti-live trypomastigote, and anti-fixed epimastigote forms of Trypanosoma cruzi.

    Science.gov (United States)

    Alessio, Glaucia Diniz; Côrtes, Denise Fonseca; Machado de Assis, Girley Francisco; Júnior, Policarpo Ademar Sales; Ferro, Eloisa Amália Vieira; Antonelli, Lis Ribeiro do Valle; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis; de Lana, Marta

    2014-11-01

    This study developed a remarkable methodological innovation (FC-ATE) which enables simultaneous detection of antibodies specific to the three evolutive forms of Trypanosoma cruzi: live amastigote (AMA), live trypomastigote (TRYPO), and fixed epimastigote (EPI) using a differential fluorescence staining as low (AMA), intermediate (TRYPO), and high (EPI). An outstanding performance (100%) was observed in the discrimination of the chagasic (CH) and non-chagasic (NCH) patients. In the applicability of FC-ATE in the diagnosis of Chagas disease, 100% of the CH samples presented positivity in the percentage of positive fluorescent parasites (PPFP) for all the three forms of T. cruzi. Moreover, 94% of the samples of NCH presented negative values of PPFP with AMA and TRYPO, and 88% with EPI. Samples from the NCH group with false-positive results were those belonging to the leishmaniasis patients. Considering the applicability of this technique in post-therapeutic monitoring of Chagas disease, 100% of non-treated (NT) and treated non-cured (TNC) samples were positive with the three T. cruzi evolutive forms, while a percentage of 100% from samples of the treated cured (TC) patients were negative with AMA, 93% with TRYPO and 96% with EPI. The comparison between FC-ATE and two other flow cytometric tests using the same samples of patients NT, TNC and TC showed that the three techniques presented different reactivities, although categorical correlation between the methodologies was observed. Taken together, the results obtained with the novel FC-ATE method have shown an outstanding performance in the diagnosis and post-therapeutic monitoring of Chagas disease. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Targeting Malignant Brain Tumors with Antibodies

    OpenAIRE

    Rok Razpotnik; Neža Novak; Vladka Čurin Šerbec; Uros Rajcevic

    2017-01-01

    Antibodies have been shown to be a potent therapeutic tool. However, their use for targeting brain diseases, including neurodegenerative diseases and brain cancers, has been limited, particularly because the blood–brain barrier (BBB) makes brain tissue hard to access by conventional antibody-targeting strategies. In this review, we summarize new antibody therapeutic approaches to target brain tumors, especially malignant gliomas, as well as their potential drawbacks. Many different brain deli...

  14. Humanization and simultaneous optimization of monoclonal antibody.

    Science.gov (United States)

    Kuramochi, T; Igawa, T; Tsunoda, H; Hattori, K

    2014-01-01

    Antibody humanization is an essential technology for reducing the potential risk of immunogenicity associated with animal-derived antibodies and has been applied to a majority of the therapeutic antibodies on the market. For developing an antibody molecule as a pharmaceutical at the current biotechnology level, however, other properties also have to be considered in parallel with humanization in antibody generation and optimization. This section describes the critical properties of therapeutic antibodies that should be sufficiently qualified, including immunogenicity, binding affinity, physiochemical stability, expression in host cells and pharmacokinetics, and the basic methodologies of antibody engineering involved. By simultaneously optimizing the antibody molecule in the light of these properties, it should prove possible to shorten the research and development period necessary to identify a highly qualified clinical candidate and consequently accelerate the start of the clinical trial.

  15. Anti-Tumor Effects of Peptide Therapeutic and Peptide Vaccine Antibody Co-targeting HER-1 and HER-2 in Esophageal Cancer (EC) and HER-1 and IGF-1R in Triple-Negative Breast Cancer (TNBC).

    Science.gov (United States)

    Overholser, Jay; Ambegaokar, Kristen Henkins; Eze, Siobhan M; Sanabria-Figueroa, Eduardo; Nahta, Rita; Bekaii-Saab, Tanios; Kaumaya, Pravin T P

    2015-07-06

    Despite the promise of targeted therapies, there remains an urgent need for effective treatment for esophageal cancer (EC) and triple-negative breast cancer (TNBC). Current FDA-approved drugs have significant problems of toxicity, safety, selectivity, efficacy and development of resistance. In this manuscript, we demonstrate that rationally designed peptide vaccines/mimics are a viable therapeutic strategy for blocking aberrant molecular signaling pathways with high affinity, specificity, potency and safety. Specifically, we postulate that novel combination treatments targeting members of the EGFR family and IGF-1R will yield significant anti-tumor effects in in vitro models of EC and TNBC possibly overcoming mechanisms of resistance. We show that the combination of HER-1 and HER-2 or HER-1 and IGF-1R peptide mimics/vaccine antibodies exhibited enhanced antitumor properties with significant inhibition of tumorigenesis in OE19 EC and MDA-MB-231 TNBC cell lines. Our work elucidates the mechanisms of HER-1/IGF-1R and HER-1/HER-2 signaling in these cancer cell lines, and the promising results support the rationale for dual targeting with HER-1 and HER-2 or IGF-1R as an improved treatment regimen for advanced therapy tailored to difference types of cancer.

  16. Characterizing Antibodies.

    Science.gov (United States)

    Weis-Garcia, Frances; Carnahan, Robert H

    2017-11-01

    Perhaps because they are such commonly used tools, many researchers view antibodies one-dimensionally: Antibody Y binds antigen X. Although few techniques require a comprehensive understanding of any particular antibody's characteristics, well-executed experiments do require a basic appreciation of what is known and, equally as important, what is not known about the antibody being used. Ignorance of the relevant antibody characteristics critical for a particular assay can easily lead to loss of precious resources (time, money, and limiting amounts of sample) and, in worst-case scenarios, erroneous conclusions. Here, we describe various antibody characteristics to provide a more well-rounded perspective of these critical reagents. With this information, it will be easier to make informed decisions on how best to choose and use the available antibodies, as well as knowing when it is essential and how to determine a particular as yet-undefined characteristic. © 2017 Cold Spring Harbor Laboratory Press.

  17. A systematic study of the effect of low pH acid treatment on anti-drug antibodies specific for a domain antibody therapeutic: Impact on drug tolerance, assay sensitivity and post-validation method assessment of ADA in clinical serum samples.

    Science.gov (United States)

    Kavita, Uma; Duo, Jia; Crawford, Sean M; Liu, Rong; Valcin, Joan; Gleason, Carol; Dong, Huijin; Gadkari, Snaehal; Dodge, Robert W; Pillutla, Renuka C; DeSilva, Binodh S

    2017-09-01

    We developed a homogeneous bridging anti-drug antibody (ADA) assay on an electro chemiluminescent immunoassay (ECLIA) platform to support the immunogenicity evaluation of a dimeric domain antibody (dAb) therapeutic in clinical studies. During method development we evaluated the impact of different types of acid at various pH levels on polyclonal and monoclonal ADA controls of differing affinities and on/off rates. The data shows for the first time that acids of different pH can have a differential effect on ADA of various affinities and this in turn impacts assay sensitivity and drug tolerance as defined by these surrogate controls. Acid treatment led to a reduction in signal of intermediate and low affinity ADA, but not high affinity or polyclonal ADA. We also found that acid pretreatment is a requisite for dissociation of drug bound high affinity ADA, but not for low affinity ADA-drug complexes. Although we were unable to identify an acid that would allow a 100% retrieval of ADA signal post-treatment, use of glycine pH3.0 enabled the detection of low, intermediate and high affinity antibodies (Abs) to various extents. Following optimization, the ADA assay method was validated for clinical sample analysis. Consistencies within various parameters of the clinical data such as dose dependent increases in ADA rates and titers were observed, indicating a reliable ADA method. Pre- and post-treatment ADA negative or positive clinical samples without detectable drug were reanalyzed in the absence of acid treatment or presence of added exogenous drug respectively to further assess the effectiveness of the final acid treatment procedure. The overall ADA results indicate that assay conditions developed and validated based on surrogate controls sufficed to provide a reliable clinical data set. The effect of low pH acid treatment on possible pre-existing ADA or soluble multimeric target in normal human serum was also evaluated, and preliminary data indicate that acid type and

  18. Human antibody technology and the development of antibodies against cytomegalovirus.

    Science.gov (United States)

    Ohlin, Mats; Söderberg-Nauclér, Cecilia

    2015-10-01

    Cytomegalovirus (CMV) is a virus that causes chronic infections in a large set of the population. It may cause severe disease in immunocompromised individuals, is linked to immunosenescence and implied to play an important role in the pathogenesis of cardiovascular diseases and cancer. Modulation of the immune system's abilities to manage the virus represent a highly viable therapeutic option and passive immunotherapy with polyclonal antibody preparations is already in clinical use. Defined monoclonal antibodies offer many advantages over polyclonal antibodies purified from serum. Human CMV-specific monoclonal antibodies have consequently been thoroughly investigated with respect to their potential in the treatment of diseases caused by CMV. Recent advances in human antibody technology have substantially expanded the breadth of antibodies for such applications. This review summarizes the fundamental basis for treating CMV disease by use of antibodies, the basic technologies to be used to develop such antibodies, and relevant human antibody specificities available to target this virus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Production systems for recombinant antibodies.

    Science.gov (United States)

    Schirrmann, Thomas; Al-Halabi, Laila; Dübel, Stefan; Hust, Michael

    2008-05-01

    Recombinant antibodies are the fastest growing class of therapeutic proteins. Furthermore, antibodies are key detection reagents in research and diagnostics. The increasing demand for antibodies with regards to amount and quality resulted in the development of a variety of recombinant production systems employing gram-negative and gram-positive bacteria, yeast and filamentous fungi, insect cell lines as well as mammalian cell lines. More recently, antibodies were also successfully produced in transgenic plants and animals. Currently, the production of recombinant antibodies for therapy is performed in mammalian cell lines to reduce the risk of immunogenicity caused by non-human post-translational modifications, in particular glycosylation. However, novel strategies already allow human-like glycosylation patterns in yeast, insect cell lines and transgenic plants. Furthermore, therapeutic strategies not requiring glycosylation of the Fc portion have been conceived, most prominently using bispecific antibodies or scFv fusion proteins, which can be produced in bacteria. Here, we review all current antibody production systems considering their advantages and limitations with respect to intended applications.

  20. Monoclonal Antibodies.

    Science.gov (United States)

    Geskin, Larisa J

    2015-10-01

    Use of monoclonal antibodies (mAbs) has revolutionized cancer therapy. Approaches targeting specific cellular targets on the malignant cells and in tumor microenvironment have been proved to be successful in hematologic malignancies, including cutaneous lymphomas. mAb-based therapy for cutaneous T-cell lymphoma has demonstrated high response rates and a favorable toxicity profile in clinical trials. Several antibodies and antibody-based conjugates are approved for use in clinical practice, and many more are in ongoing and planned clinical trials. In addition, these safe and effective drugs can be used as pillars for sequential therapies in a rational stepwise manner. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Thyroid Antibodies

    Science.gov (United States)

    ... Factor Antibody Iron Iron Tests JAK2 Mutation Kidney Stone Analysis Kidney Stone Risk Panel KRAS Mutation Lactate Lactate Dehydrogenase (LD) ... gain Fatigue Dry skin Hair loss Intolerance to cold Constipation A high level of thyroid hormone ( hyperthyroidism ) ...

  2. Conference scene: progress with promising human antibodies.

    Science.gov (United States)

    Larrick, James W

    2012-03-01

    Antibodies and antibody-based therapeutics have become big business, with annual sales over US$50 billion, accounting for >6% of worldwide pharmaceutical revenues. Ten molecules have blockbuster status (>US$1 billion), with six generating more than US$6 billion in sales. In excess of 300 products based on this rapidly maturing technology are in clinical trials. The generation and manufacture of human antibodies is now routine, although the cost of goods remains an issue. Optimizing combinations of antibodies with other therapeutics (e.g., chemotherapy) is a major short-term goal, while target validation and product differentiation remain significant hurdles if growth is to continue. Some of the notable highlights of the recent 16th International Conference on Human Antibodies and Hybridomas meeting in Cannes, France are described below. The conference was sponsored by the international journal Human Antibodies, in association with the Integrative Medical Sciences Association (IMSA). The Program Chairman was Professor Mark Glassy, IMSA, San Diego, CA, USA.

  3. Polyclonal and monoclonal antibodies in clinic.

    Science.gov (United States)

    Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

    2014-01-01

    Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

  4. Anti-influenza M2e antibody

    Science.gov (United States)

    Bradbury, Andrew M [Santa Fe, NM

    2011-12-20

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  5. Anti-influenza M2e antibody

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, Andrew M.

    2013-04-16

    Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

  6. Plant antibodies for immunotherapy.

    Science.gov (United States)

    Ma, J K; Hein, M B

    1995-01-01

    The original report of Hiatt (1989) initiated a wave of excitement at the realization that a complex mammalian protein such as immunoglobulin could be assembled within a plant cell. The general reaction was one of amazement, but interest in exploiting the possibilities arising from the discovery, for example to make antibodies of therapeutic value, has taken a considerable time to develop. In the meantime, other recombinant expression systems and traditional cell culture techniques have advanced and overcome some of their problems, particularly those associated with yields. Plants, however, still offer unique advantages, especially in their ability to match the protein assembly capabilities of mammalian cells (as demonstrated by the assembly of SIgA molecules), as well as to provide antibodies in bulk at low cost. In addition, the area of "immunization" of plants holds great promise and will surely be a field of enormous growth for the future. PMID:7480334

  7. Chimeric antibodies.

    Science.gov (United States)

    Kurosawa, Kohei; Lin, Waka; Ohta, Kunihiro

    2014-01-01

    Here we describe a detailed protocol for the one-step preparation of antigen-specific human chimeric immunoglobulin G (IgG) monoclonal antibodies (mAbs) using an in vitro antibody design method referred to as the ADLib (Autonomously Diversifying Library) system. This method employs a chicken B cell line DT40-based library in which the variable regions of the Ig gene loci have been highly diversified by treatment with the histone deacetylase inhibitors. DT40 cells express both membrane-bound and secreted forms of chicken IgM. This property allows a rapid screening and selection of antibody-producing B cells from the library by using magnetic beads conjugated with any antigen of interest. To apply the ADLib system to the direct generation of human chimeric antibody, we have inserted a DNA segment coding for the constant region of human IgG into the chicken IgM heavy-chain locus of DT40 cells by homologous gene targeting. By a mechanism of alternative splicing, the resulting DT40 strain simultaneously expresses chimeric human IgG that contain the same Ig variable region sequences as the membrane-bound chicken IgM displayed at the cell surface. Application of the ADLib system to this human Ig-inserted DT40 strain enables the one-step isolation of human chimeric IgG that is specific for any antigen of interest and can be easily purified for immediate use.

  8. Antibody biotechnology

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... from somatic recombination between variable genes, was made. This topic has preoccupied immunologists includ- ing Ehrlich (side chain theory), Jerne .... natural naïve libraries, syn- thetic naïve and semi-synthetic libraries. Immune antibody libraries. These libraries are constructed with VH (VDJ) and VL.

  9. Catalytic Antibodies

    Indian Academy of Sciences (India)

    systemic lupus erythematosus, multiple sclerosis and rheumatoid arthritis. The importance of natural immunological mechanisms in pro- ducing artificial catalysts is exemplified by the reports describing increased synthesis of esterase antibodies in autoimmune mice compared to normal mice in response to transition-state ...

  10. When binding is enough: nonactivating antibody formats

    NARCIS (Netherlands)

    Labrijn, Aran F.; Aalberse, Rob C.; Schuurman, Janine

    2008-01-01

    Most therapeutic antibodies currently used in the clinic are based on the human IgG1 format, which is a bivalent molecule that efficiently interacts with the immune system's effector functions. In clinical applications where binding to the target alone is sufficient for therapeutic efficacy;

  11. High throughput screening for antibody induced complement-dependent cytotoxicity in early antibody discovery using homogeneous macroconfocal fluorescence imaging

    NARCIS (Netherlands)

    Gerritsen, Arnout F.; Bosch, Martijn; de Weers, Michel; van de Winkel, Jan G. J.; Parren, Paul W. H. I.

    2010-01-01

    Complement-dependent cytotoxicity (CDC) represents an important Fc-mediated effector function of antibodies and is a quality often sought in candidates for therapeutic antibody development in cancer. Antibodies inducing potent CDC are relatively rare as the ability to induce CDC is strongly

  12. Antiparietal cell antibody test

    Science.gov (United States)

    APCA; Anti-gastric parietal cell antibody; Atrophic gastritis - anti-gastric parietal cell antibody; Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; ...

  13. Theranostic applications of antibodies in oncology.

    Science.gov (United States)

    Fleuren, Emmy D G; Versleijen-Jonkers, Yvonne M H; Heskamp, Sandra; van Herpen, Carla M L; Oyen, Wim J G; van der Graaf, Winette T A; Boerman, Otto C

    2014-06-01

    Targeted therapies, including antibodies, are becoming increasingly important in cancer therapy. Important limitations, however, are that not every patient benefits from a specific antibody therapy and that responses could be short-lived due to acquired resistance. In addition, targeted therapies are quite expensive and are not completely devoid of side-effects. This urges the need for accurate patient selection and response monitoring. An important step towards personalizing antibody treatment could be the implementation of theranostics. Antibody theranostics combine the diagnostic and therapeutic potential of an antibody, thereby selecting those patients who are most likely to benefit from antibody treatment. This review focuses on the clinical application of theranostic antibodies in oncology. It provides detailed information concerning the suitability of antibodies for theranostics, the different types of theranostic tests available and summarizes the efficacy of theranostic antibodies used in current clinical practice. Advanced theranostic applications, including radiolabeled antibodies for non-invasive functional imagining, are also addressed. Finally, we discuss the importance of theranostics in the emerging field of personalized medicine and critically evaluate recent data to determine the best way to apply antibody theranostics in the future. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  14. Targeting Malignant Brain Tumors with Antibodies.

    Science.gov (United States)

    Razpotnik, Rok; Novak, Neža; Čurin Šerbec, Vladka; Rajcevic, Uros

    2017-01-01

    Antibodies have been shown to be a potent therapeutic tool. However, their use for targeting brain diseases, including neurodegenerative diseases and brain cancers, has been limited, particularly because the blood-brain barrier (BBB) makes brain tissue hard to access by conventional antibody-targeting strategies. In this review, we summarize new antibody therapeutic approaches to target brain tumors, especially malignant gliomas, as well as their potential drawbacks. Many different brain delivery platforms for antibodies have been studied such as liposomes, nanoparticle-based systems, cell-penetrating peptides (CPPs), and cell-based approaches. We have already shown the successful delivery of single-chain fragment variable (scFv) with CPP as a linker between two variable domains in the brain. Antibodies normally face poor penetration through the BBB, with some variants sufficiently passing the barrier on their own. A "Trojan horse" method allows passage of biomolecules, such as antibodies, through the BBB by receptor-mediated transcytosis (RMT). Such examples of therapeutic antibodies are the bispecific antibodies where one binding specificity recognizes and binds a BBB receptor, enabling RMT and where a second binding specificity recognizes an antigen as a therapeutic target. On the other hand, cell-based systems such as stem cells (SCs) are a promising delivery system because of their tumor tropism and ability to cross the BBB. Genetically engineered SCs can be used in gene therapy, where they express anti-tumor drugs, including antibodies. Different types and sources of SCs have been studied for the delivery of therapeutics to the brain; both mesenchymal stem cells (MSCs) and neural stem cells (NSCs) show great potential. Following the success in treatment of leukemias and lymphomas, the adoptive T-cell therapies, especially the chimeric antigen receptor-T cells (CAR-Ts), are making their way into glioma treatment as another type of cell-based therapy using the

  15. Targeting Malignant Brain Tumors with Antibodies

    Directory of Open Access Journals (Sweden)

    Rok Razpotnik

    2017-09-01

    Full Text Available Antibodies have been shown to be a potent therapeutic tool. However, their use for targeting brain diseases, including neurodegenerative diseases and brain cancers, has been limited, particularly because the blood–brain barrier (BBB makes brain tissue hard to access by conventional antibody-targeting strategies. In this review, we summarize new antibody therapeutic approaches to target brain tumors, especially malignant gliomas, as well as their potential drawbacks. Many different brain delivery platforms for antibodies have been studied such as liposomes, nanoparticle-based systems, cell-penetrating peptides (CPPs, and cell-based approaches. We have already shown the successful delivery of single-chain fragment variable (scFv with CPP as a linker between two variable domains in the brain. Antibodies normally face poor penetration through the BBB, with some variants sufficiently passing the barrier on their own. A “Trojan horse” method allows passage of biomolecules, such as antibodies, through the BBB by receptor-mediated transcytosis (RMT. Such examples of therapeutic antibodies are the bispecific antibodies where one binding specificity recognizes and binds a BBB receptor, enabling RMT and where a second binding specificity recognizes an antigen as a therapeutic target. On the other hand, cell-based systems such as stem cells (SCs are a promising delivery system because of their tumor tropism and ability to cross the BBB. Genetically engineered SCs can be used in gene therapy, where they express anti-tumor drugs, including antibodies. Different types and sources of SCs have been studied for the delivery of therapeutics to the brain; both mesenchymal stem cells (MSCs and neural stem cells (NSCs show great potential. Following the success in treatment of leukemias and lymphomas, the adoptive T-cell therapies, especially the chimeric antigen receptor-T cells (CAR-Ts, are making their way into glioma treatment as another type of cell

  16. Changes in serum trough levels of infliximab during treatment intensification but not in anti-infliximab antibody detection are associated with clinical outcomes after therapeutic failure in Crohn's disease

    DEFF Research Database (Denmark)

    Steenholdt, Casper; Bendtzen, Klaus; Brynskov, Jørn

    2015-01-01

    and anti-IFX antibodies (Abs) after IFX intensification and clinical outcomes. METHODS: We performed a post hoc analysis of a randomized clinical trial including 42 Crohn's disease patients with IFX treatment failure, all treated with an intensified IFX regimen (5mg/kg every 4 week) for 12 weeks. Trough......BACKGROUND AND AIMS: Intensification of the infliximab (IFX) regimen is recommended if the treatment effect is inadequate. However, the rationale for this is not well defined as the underlying mechanisms vary. The aim of this study was to explore the association between changes in serum IFX...

  17. Clinical efficacy and management of monoclonal antibodies targeting CD38 and SLAMF7 in multiple myeloma

    DEFF Research Database (Denmark)

    van de Donk, Niels W C J; Moreau, Philippe; Plesner, Torben

    2016-01-01

    Immunotherapeutic strategies are emerging as promising therapeutic approaches in multiple myeloma (MM), with several monoclonal antibodies in advanced stages of clinical development. Of these agents, CD38-targeting antibodies have marked single agent activity in extensively pretreated MM, and pre...

  18. Expression cloning and production of human heavy-chain-only antibodies from murine transgenic plasma cells

    NARCIS (Netherlands)

    D.D. Drabek (Dubravka); R. Janssens (Rick); Boer, E. (Ernie de); Rademaker, R. (Rik); Kloess, J. (Johannes); J.J. Skehel (John ); Grosveld, F. (Frank)

    2016-01-01

    textabstractSeveral technologies have been developed to isolate human antibodies against different target antigens as a source of potential therapeutics, including hybridoma technology, phage and yeast display systems. For conventional antibodies, this involves either random pairing of VH and

  19. Neutralisation of HIV-1 cell-cell spread by human and llama antibodies

    National Research Council Canada - National Science Library

    McCoy, Laura E; Groppelli, Elisabetta; Blanchetot, Christophe; de Haard, Hans; Verrips, Theo; Rutten, Lucy; Weiss, Robin A; Jolly, Clare

    2014-01-01

    .... Much current vaccine research involves the study of broadly neutralising antibodies (bNabs) that arise during natural infection with the aims of eliciting such antibodies by vaccination or incorporating them into novel therapeutics...

  20. Anti-Tumor Effects of Peptide Therapeutic and Peptide Vaccine Antibody Co-targeting HER-1 and HER-2 in Esophageal Cancer (EC) and HER-1 and IGF-1R in Triple-Negative Breast Cancer (TNBC)

    OpenAIRE

    Jay Overholser; Kristen Henkins Ambegaokar; Siobhan M. Eze; Eduardo Sanabria-Figueroa; Rita Nahta; Tanios Bekaii-Saab; Pravin T.P. Kaumaya

    2015-01-01

    Despite the promise of targeted therapies, there remains an urgent need for effective treatment for esophageal cancer (EC) and triple-negative breast cancer (TNBC). Current FDA-approved drugs have significant problems of toxicity, safety, selectivity, efficacy and development of resistance. In this manuscript, we demonstrate that rationally designed peptide vaccines/mimics are a viable therapeutic strategy for blocking aberrant molecular signaling pathways with high affinity, specificity, pot...

  1. Therapeutic Plasmapheresis in Kidney Transplantation

    Directory of Open Access Journals (Sweden)

    Zeynep Kendi Celebi

    2013-02-01

    Full Text Available In 1960's, with succesfully renal transplantations, acute rejection became to be a serious problem for graft survival. From 1965 to 2010, with the introduction of new immunosuppressant agents such as cyclosporine, mycophenolate mofetile and tacrolimus, the acute rejection rates declined from 80% to 10% . There is an ongoing gradual improvement in allograft survival. Use of Therapeutic plasma exchange (TPE is not evidence based treatment, but TPE is necessary for pre- and also post transplantation in patients with DSA. TPE is also a main treatment for antibody mediated rejection (AMR , but in clinical practice the duration and frequency of TPE and individual difference of antibody production is unclear. There is a requirement for more specific antibody elimination. Further randomised controlled studies are needed to elucidate TPE use before and after kidney transplantation. [Dis Mol Med 2013; 1(1.000: 8-10

  2. Therapeutic Nanodevices

    Science.gov (United States)

    Lee, Stephen; Ruegsegger, Mark; Barnes, Philip; Smith, Bryan; Ferrari, Mauro

    Therapeutic nanotechnology offers minimally invasive therapies with high densities of function concentrated in small volumes, features that may reduce patient morbidity and mortality. Unlike other areas of nanotechnology, novel physical properties associated with nanoscale dimensionality are not the raison d'être of therapeutic nanotechnology, whereas the aggregation of multiple biochemical (or comparably precise) functions into controlled nanoarchitectures is. Multifunctionality is a hallmark of emerging nanotherapeutic devices, and multifunctionality can allow nanotherapeutic devices to perform multistep work processes, with each functional component contributing to one or more nanodevice subroutine such that, in aggregate, subroutines sum to a cogent work process. Cannonical nanotherapeutic subroutines include tethering (targeting) to sites of disease, dispensing measured doses of drug (or bioactive compound), detection of residual disease after therapy and communication with an external clinician/operator. Emerging nanotherapeutics thus blur the boundaries between medical devices and traditional pharmaceuticals. Assembly of therapeutic nanodevices generally exploits either (bio)material self-assembly properties or chemoselective bioconjugation techniques, or both. Given the complexity, composition, and the necessity for their tight chemical and structural definition inherent in the nature of nanotherapeutics, their cost of goods (COGs) might exceed that of (already expensive) biologics. Early therapeutic nanodevices will likely be applied to disease states which exhibit significant unmet patient need (cancer and cardiovascular disease), while application to other disease states well-served by conventional therapy may await perfection of nanotherapeutic design and assembly protocols.

  3. RBC Antibody Screen

    Science.gov (United States)

    ... products and services. Advertising & Sponsorship: Policy | Opportunities RBC Antibody Screen Share this page: Was this page helpful? ... Indirect Coombs Test; Indirect Anti-human Globulin Test; Antibody Screen Formal name: Red Blood Cell Antibody Screen ...

  4. Intellectual property protection: strategies for antibody inventions.

    Science.gov (United States)

    Storz, Ulrich

    2011-01-01

    In the last decade, therapeutic antibodies have become one of the commercially most successful classes of biopharmaceutical drugs. Major drug manufacturers who have successfully managed to occupy this new market, as well as biotechnology firms, some of which have experienced a quick growth and are now on par with the former, owe part of their success to suitable intellectual property strategies. This article provides an overview of the current thinking on antibody-related patents, and discusses strategies for protecting the antibody products of the future.

  5. Antibody Conjugates: From Heterogeneous Populations to Defined Reagents

    Directory of Open Access Journals (Sweden)

    Patrick Dennler

    2015-08-01

    Full Text Available Monoclonal antibodies (mAbs and their derivatives are currently the fastest growing class of therapeutics. Even if naked antibodies have proven their value as successful biopharmaceuticals, they suffer from some limitations. To overcome suboptimal therapeutic efficacy, immunoglobulins are conjugated with toxic payloads to form antibody drug conjugates (ADCs and with chelating systems bearing therapeutic radioisotopes to form radioimmunoconjugates (RICs. Besides their therapeutic applications, antibody conjugates are also extensively used for many in vitro assays. A broad variety of methods to functionalize antibodies with various payloads are currently available. The decision as to which conjugation method to use strongly depends on the final purpose of the antibody conjugate. Classical conjugation via amino acid residues is still the most common method to produce antibody conjugates and is suitable for most in vitro applications. In recent years, however, it has become evident that antibody conjugates, which are generated via site-specific conjugation techniques, possess distinct advantages with regard to in vivo properties. Here, we give a comprehensive overview on existing and emerging strategies for the production of covalent and non-covalent antibody conjugates.

  6. HIV antibodies for treatment of HIV infection

    Science.gov (United States)

    Margolis, David M.; Koup, Richard A.; Ferrari, Guido

    2016-01-01

    Summary The bar is high to improve on current combination antiretroviral therapy (ART), now highly effective, safe, and simple. However antibodies that bind the HIV envelope are able to uniquely target the virus as it seeks to enter new target cells, or as it is expressed from previously infected cells. Further, the use of antibodies against HIV as a therapeutic may offer advantages. Antibodies can have long half-lives, and are being considered as partners for long-acting antiretrovirals for use in therapy or prevention of HIV infection. Early studies in animal models and in clinical trials suggest that such antibodies can have antiviral activity but, as with small molecule antiretrovirals, the issues of viral escape and resistance will have to be addressed. Most promising, however, are the unique properties of anti-HIV antibodies: the potential ability to opsonize viral particles, to direct antibody-dependent cellular cytotoxicity (ADCC) against actively infected cells, and ultimately the ability to direct the clearance of HIV-infected cells by effector cells of the immune system. These distinctive activities suggest that HIV antibodies and their derivatives may play an important role in the next frontier of HIV therapeutics, the effort to develop treatments that could lead to an HIV cure. PMID:28133794

  7. Discovery of diverse and functional antibodies from large human repertoire antibody libraries.

    Science.gov (United States)

    Schwimmer, Lauren J; Huang, Betty; Giang, Hoa; Cotter, Robyn L; Chemla-Vogel, David S; Dy, Francis V; Tam, Eric M; Zhang, Fangjiu; Toy, Pamela; Bohmann, David J; Watson, Susan R; Beaber, John W; Reddy, Nithin; Kuan, Hua-Feng; Bedinger, Daniel H; Rondon, Isaac J

    2013-05-31

    Phage display antibody libraries have a proven track record for the discovery of therapeutic human antibodies, increasing the demand for large and diverse phage antibody libraries for the discovery of new therapeutics. We have constructed naïve antibody phage display libraries in both Fab and scFv formats, with each library having more than 250 billion clones that encompass the human antibody repertoire. These libraries show high fidelity in open reading frame and expression percentages, and their V-gene family distribution, VH-CDR3 length and amino acid usage mirror the natural diversity of human antibodies. Both the Fab and scFv libraries show robust sequence diversity in target-specific binders and differential V-gene usage for each target tested, supporting the use of libraries that utilize multiple display formats and V-gene utilization to maximize antibody-binding diversity. For each of the targets, clones with picomolar affinities were identified from at least one of the libraries and for the two targets assessed for activity, functional antibodies were identified from both libraries. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. CD47-signal regulatory protein-α (SIRPα) interactions form a barrier for antibody-mediated tumor cell destruction

    NARCIS (Netherlands)

    Zhao, Xi Wen; van Beek, Ellen M.; Schornagel, Karin; van der Maaden, Hans; van Houdt, Michel; Otten, Marielle A.; Finetti, Pascal; van Egmond, Marjolein; Matozaki, Takashi; Kraal, Georg; Birnbaum, Daniel; van Elsas, Andrea; Kuijpers, Taco W.; Bertucci, Francois; van den Berg, Timo K.

    2011-01-01

    Monoclonal antibodies are among the most promising therapeutic agents for treating cancer. Therapeutic cancer antibodies bind to tumor cells, turning them into targets for immune-mediated destruction. We show here that this antibody-mediated killing of tumor cells is limited by a mechanism involving

  9. Assessment of absorbed dose and therapeutic response of tumor in repeated high-dose I-131 anti-CD20 monoclonal antibody (rituximab) radioimmunotherapy for non-Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Byung Hyun; Lim, Sang Moo; Kim, Kyeong Min [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)] (and others)

    2007-07-01

    We assessed the therapeutic dose absorbed to the tumor and response in repeated RIT with I-131 rituximab for NHL. Patients with NHL (n=6) were administered a therapeutic dose of I-131 rituximab (192.527.0 mCi). The number of repeated administration was 3 for all patients. Total 12 measurable tumor regions were assessed at the time of each RIT. Whole-body (WB) planar images with anterior and posterior views were acquired sequentially at 5 min, 5hr, 24hr, 48hr, and 72hr post-injection using gamma camera. F-18-FDG PET/CT was performed before (within 7 days) and after (on Day 30) RIT. From PET/CT image acquired before RIT, maximum intensity projection (MIP) image of coronal view was acquired. Serial WB planar images were overlaid to the coronal MIP PET image, respectively, by means of registration using 4 fiducial marks (bilateral shoulder and buttock) implemented in AMIDE software. On registered MIP PET and WB planar images, both 2D-ROIs were drawn on the region of tumor and background nearby tumor. The shape of 2D-ROI of tumor was determined from the MIP PET image. The volume of tumor was measured from the CT image, the % change of tumor volume before and after RIT was used in evaluation of the therapeutic response. The values of CT-based tumor volume were 8.216.3cc. The values of absorbed dose for tumor and the % changes of tumor volume before and after RIT were 231.8603.0rad, and 55.548.7%, respectively, and did not show the linear relationship (r=0.2787). The values of absorbed dose for tumor and the % changes of tumor volume did not correlate with the number of repeated administration (p>0.05, ANOVA). Aligning PET and planar images could estimate the quantitative values of absorbed dose to tumor. The data suggest that repeated RIT with I-131 rituximab is necessary for NHL, because single-RIT is insufficient to achieve remission of disease.

  10. Computationally driven antibody engineering enables simultaneous humanization and thermostabilization.

    Science.gov (United States)

    Choi, Yoonjoo; Ndong, Christian; Griswold, Karl E; Bailey-Kellogg, Chris

    2016-10-01

    Humanization reduces the immunogenicity risk of therapeutic antibodies of non-human origin. Thermostabilization can be critical for clinical development and application of therapeutic antibodies. Here, we show that the computational antibody redesign method Computationally Driven Antibody Humanization (CoDAH) enables these two goals to be accomplished simultaneously and seamlessly. A panel of CoDAH designs for the murine parent of cetuximab, a chimeric anti-EGFR antibody, exhibited both substantially improved thermostabilities and substantially higher levels of humanness, while retaining binding activity near the parental level. The consistently high quality of the turnkey CoDAH designs, over a whole panel of variants, suggests that the computationally directed approach encapsulates key determinants of antibody structure and function. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Antibody Positron Emission Tomography Imaging in Anticancer Drug Development

    NARCIS (Netherlands)

    Lamberts, Laetitia E.; Williams, Simon P.; Terwisscha Van Scheltinga, Anton; Lub-de Hooge, Marjolijn N.; Schroeder, Carolien P.; Gietema, Jourik A.; Brouwers, Adrienne H.; de Vries, Elisabeth G. E.

    2015-01-01

    More than 50 monoclonal antibodies (mAbs), including several antibody-drug conjugates, are in advanced clinical development, forming an important part of the many molecularly targeted anticancer therapeutics currently in development. Drug development is a relatively slow and expensive process,

  12. Nanobodies - the new concept in antibody engineering | Deffar ...

    African Journals Online (AJOL)

    Importantly, the cloned and isolated VHH domain is a perfectly stable polypeptide harboring the full antigen-binding capacity of the original heavy-chain antibody. These newly discovered VHH domains with their unique structural and functional properties form the basis of a new generation of therapeutic antibodies which ...

  13. Postbooster Antibodies from Humans as Source of Diphtheria Antitoxin.

    Science.gov (United States)

    Bermejo-Martin, Jesús F; Avila-Alonso, Ana; González-Rivera, Milagros; Tamayo, Eduardo; Eiros, Jose María; Almansa, Raquel

    2016-07-01

    Diphtheria antitoxin for therapeutic use is in limited supply. A potential source might be affinity-purified antibodies originally derived from plasma of adults who received a booster dose of a vaccine containing diphtheria toxoid. These antibodies might be useful for treating even severe cases of diphtheria.

  14. Molecular farming of recombinant antibodies in plants.

    Science.gov (United States)

    Schillberg, S; Fischer, R; Emans, N

    2003-03-01

    Antibodies represent a large proportion of therapeutic drugs currently in development. In most cases, they are produced in mammalian cell lines or transgenic animals because these have been shown to fold and assemble the proteins correctly and generate authentic glycosylation patterns. However, such expression systems are expensive, difficult to scale up and there are safety concerns due to potential contamination with pathogenic organisms or oncogenic DNA sequences. Plants represent an inexpensive, efficient and safe alternative for the production of recombinant antibodies. Research over the last 10 years has shown that plants can produce a variety of functional antibodies and there is now intense interest in scaling up production to commercial levels. In this review, we discuss the advantages of plants over traditional expression systems, describe how antibody expression in plants is achieved and optimized and then consider the practical issues concerning large-scale molecular farming in plants. The first plant-produced therapeutic antibodies are already in clinical trials, and, given the economic benefits of this production system, we are likely to see many more recombinant antibodies produced in this manner in the future.

  15. Changes in serum trough levels of infliximab during treatment intensification but not in anti-infliximab antibody detection are associated with clinical outcomes after therapeutic failure in Crohn's disease.

    Science.gov (United States)

    Steenholdt, Casper; Bendtzen, Klaus; Brynskov, Jørn; Thomsen, Ole Ø; Munck, Lars K; Christensen, Lisbet A; Pedersen, Gitte; Kjeldsen, Jens; Ainsworth, Mark A

    2015-03-01

    Intensification of the infliximab (IFX) regimen is recommended if the treatment effect is inadequate. However, the rationale for this is not well defined as the underlying mechanisms vary. The aim of this study was to explore the association between changes in serum IFX and anti-IFX antibodies (Abs) after IFX intensification and clinical outcomes. We performed a post hoc analysis of a randomized clinical trial including 42 Crohn's disease patients with IFX treatment failure, all treated with an intensified IFX regimen (5mg/kg every 4 week) for 12 weeks. Trough serum IFX and anti-IFX Ab concentrations were measured by a homogeneous mobility shift binding assay (HMSA) and a functional cell-based reporter gene assay (RGA) at treatment failure and the end of the trial. Twenty-one patients (50%) regained clinical response on the intensified IFX regimen. The increase in serum trough levels of IFX during treatment intensification was higher among responders than non-responders (RGA, 8.8 versus 3.0 μg/mL, p = 0.035; HMSA, 9.9 versus 4.7 μg/mL, p = 0.040), and differentiated patients by clinical outcome (RGA, area under receiver operating characteristic curve [AUC] 0.75 [0.53-0.97], p = 0.035; HMSA, AUC 0.74 [0.53-0.95], p = 0.042). All responders exhibited an IFX increase ≥2.6 μg/mL (sensitivity 100%, specificity 50%). Anti-IFX Abs detected by HMSA in 13 patients (32%) were often non-functional and became undetectable during IFX intensification. However, even functional anti-IFX Abs detected by RGA in six patients (15%) became undetectable. Increase in IFX levels following treatment intensification was associated with improved clinical outcomes, indicating insufficient drug levels in a subgroup of patients. Anti-IFX Abs may become undetectable during treatment intensification, suggesting lowered production or the formation of immune complexes. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights

  16. Antibody or Antibody Fragments: Implications for Molecular Imaging and Targeted Therapy of Solid Tumors

    Directory of Open Access Journals (Sweden)

    Katerina T. Xenaki

    2017-10-01

    Full Text Available The use of antibody-based therapeutics has proven very promising for clinical applications in cancer patients, with multiple examples of antibodies and antibody–drug conjugates successfully applied for the treatment of solid tumors and lymphomas. Given reported recurrence rates, improvements are clearly still necessary. A major factor limiting the efficacy of antibody-targeted cancer therapies may be the incomplete penetration of the antibody or antibody–drug conjugate into the tumor. Incomplete tumor penetration also affects the outcome of molecular imaging, when using such targeting agents. From the injection site until they arrive inside the tumor, targeting molecules are faced with several barriers that impact intratumoral distribution. The primary means of antibody transport inside tumors is based on diffusion. The diffusive penetration inside the tumor is influenced by both antibody properties, such as size and binding affinity, as well as tumor properties, such as microenvironment, vascularization, and targeted antigen availability. Engineering smaller antibody fragments has shown to improve the rate of tumor uptake and intratumoral distribution. However, it is often accompanied by more rapid clearance from the body and in several cases also by inherent destabilization and reduction of the binding affinity of the antibody. In this perspective, we discuss different cancer targeting approaches based on antibodies or their fragments. We carefully consider how their size and binding properties influence their intratumoral uptake and distribution, and how this may affect cancer imaging and therapy of solid tumors.

  17. Antibodies as Mediators of Brain Pathology.

    Science.gov (United States)

    Brimberg, Lior; Mader, Simone; Fujieda, Yuichiro; Arinuma, Yoshiyuki; Kowal, Czeslawa; Volpe, Bruce T; Diamond, Betty

    2015-11-01

    The brain is normally sequestered from antibody exposure by the blood brain barrier. However, antibodies can access the brain during fetal development before the barrier achieves full integrity, and in disease states when barrier integrity is compromised. Recent studies suggest that antibodies contribute to brain pathology associated with autoimmune diseases such as systemic lupus erythematosus and neuromyelitis optica, and can lead to transient or permanent behavioral or cognitive abnormalities. We review these findings here and examine the circumstances associated with antibody entry into the brain, the routes of access and the mechanisms that then effect pathology. Understanding these processes and the nature and specificity of neuronal autoantibodies may reveal therapeutic strategies toward alleviating or preventing the neurological pathologies and behavioral abnormalities associated with autoimmune disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. New Strategies Using Antibody Combinations to Increase Cancer Treatment Effectiveness

    Directory of Open Access Journals (Sweden)

    Isabel Corraliza-Gorjón

    2017-12-01

    Full Text Available Antibodies have proven their high value in antitumor therapy over the last two decades. They are currently being used as the first-choice to treat some of the most frequent metastatic cancers, like HER2+ breast cancers or colorectal cancers, currently treated with trastuzumab (Herceptin and bevacizumab (Avastin, respectively. The impressive therapeutic success of antibodies inhibiting immune checkpoints has extended the use of therapeutic antibodies to previously unanticipated tumor types. These anti-immune checkpoint antibodies allowed the cure of patients devoid of other therapeutic options, through the recovery of the patient’s own immune response against the tumor. In this review, we describe how the antibody-based therapies will evolve, including the use of antibodies in combinations, their main characteristics, advantages, and how they could contribute to significantly increase the chances of success in cancer therapy. Indeed, novel combinations will consist of mixtures of antibodies against either different epitopes of the same molecule or different targets on the same tumor cell; bispecific or multispecific antibodies able of simultaneously binding tumor cells, immune cells or extracellular molecules; immunomodulatory antibodies; antibody-based molecules, including fusion proteins between a ligand or a receptor domain and the IgG Fab or Fc fragments; autologous or heterologous cells; and different formats of vaccines. Through complementary mechanisms of action, these combinations could contribute to elude the current limitations of a single antibody which recognizes only one particular epitope. These combinations may allow the simultaneous attack of the cancer cells by using the help of the own immune cells and exerting wider therapeutic effects, based on a more specific, fast, and robust response, trying to mimic the action of the immune system.

  19. [Biophysical Characterization of Biopharmaceuticals, Including Antibody Drugs].

    Science.gov (United States)

    Uchiyama, Susumu

    2016-01-01

    Biopharmaceuticals, including antibody drugs, are now popular because of their high specificity with low adverse effects, especially in the treatment of cancer and autoimmune diseases. However, because the active pharmaceutical ingredients of biopharmaceuticals are proteins, biophysical characterization of these therapeutic proteins should be required. In this manuscript, methods of chemical and physical characterization of therapeutic proteins are described. In terms of chemical characterization, analysis of chemical modifications of the constituent amino acids is explained. Physical characterization includes higher order structural analysis and assessment of protein aggregates. Quantification methods of aggregates with different sizes, recently encouraged by the U.S. Food and Drug Administration (FDA), are introduced. As for the stability of therapeutic proteins, the importance of chemical and physical stability is explained. Finally, the contribution of colloidal and structural stability to the production of an antibody drug less prone to aggregation is introduced.

  20. Utilisation of antibody microarrays for the selection of specific and informative antibodies from recombinant library binders of unknown quality

    DEFF Research Database (Denmark)

    Kibat, Janek; Schirrmann, Thomas; Knape, Matthias J

    2016-01-01

    Many diagnostic and therapeutic concepts require antibodies of high specificity. Recombinant binder libraries and related selection approaches allow the efficient isolation of antibodies against almost every target of interest. Nevertheless, it cannot be guaranteed that selected antibodies perform...... well and interact specifically enough with analytes unless an elaborate characterisation is performed. Here, we present an approach to shorten this process by combining the selection of suitable antibodies with the identification of informative target molecules by means of antibody microarrays, thereby...... with more than one of the scFvs binding to these targets. Only the relevant antibodies were then characterised further on antigen microarrays and by surface plasmon resonance experiments so as to select the most specific and highest affinity antibodies. These binders were in turn used to confirm...

  1. Structure Based Antibody-Like Peptidomimetics

    Directory of Open Access Journals (Sweden)

    Mark I. Greene

    2012-02-01

    Full Text Available Biologics such as monoclonal antibodies (mAb and soluble receptors represent new classes of therapeutic agents for treatment of several diseases. High affinity and high specificity biologics can be utilized for variety of clinical purposes. Monoclonal antibodies have been used as diagnostic agents when coupled with radionuclide, immune modulatory agents or in the treatment of cancers. Among other limitations of using large molecules for therapy the actual cost of biologics has become an issue. There is an effort among chemists and biologists to reduce the size of biologics which includes monoclonal antibodies and receptors without a reduction of biological efficacy. Single chain antibody, camel antibodies, Fv fragments are examples of this type of deconstructive process. Small high-affinity peptides have been identified using phage screening. Our laboratory used a structure-based approach to develop small-size peptidomimetics from the three-dimensional structure of proteins with immunoglobulin folds as exemplified by CD4 and antibodies. Peptides derived either from the receptor or their cognate ligand mimics the functions of the parental macromolecule. These constrained peptides not only provide a platform for developing small molecule drugs, but also provide insight into the atomic features of protein-protein interactions. A general overview of the reduction of monoclonal antibodies to small exocyclic peptide and its prospects as a useful diagnostic and as a drug in the treatment of cancer are discussed.

  2. Generation of monoclonal antibodies against highly conserved antigens.

    Directory of Open Access Journals (Sweden)

    Hongzhe Zhou

    Full Text Available BACKGROUND: Therapeutic antibody development is one of the fastest growing areas of the pharmaceutical industry. Generating high-quality monoclonal antibodies against a given therapeutic target is very crucial for the success of the drug development. However, due to immune tolerance, some proteins that are highly conserved between mice and humans are not very immunogenic in mice, making it difficult to generate antibodies using a conventional approach. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the impaired immune tolerance of NZB/W mice was exploited to generate monoclonal antibodies against highly conserved or self-antigens. Using two highly conserved human antigens (MIF and HMGB1 and one mouse self-antigen (TNF-alpha as examples, we demonstrate here that multiple clones of high affinity, highly specific antibodies with desired biological activities can be generated, using the NZB/W mouse as the immunization host and a T cell-specific tag fused to a recombinant antigen to stimulate the immune system. CONCLUSIONS/SIGNIFICANCE: We developed an efficient and universal method for generating surrogate or therapeutic antibodies against "difficult antigens" to facilitate the development of therapeutic antibodies.

  3. Variable fragments of heavy chain antibodies (VHHs): a new magic bullet molecule of medicine?

    Science.gov (United States)

    Smolarek, Dorota; Bertrand, Olivier; Czerwinski, Marcin

    2012-06-14

     Serum of animals belonging to the Camelidae family (camels and llamas) contains fully active antibodies that are naturally devoid of light chains. Variable domains derived from heavy chain antibodies (hcAb) called VHHs or nanobodies™ can bind antigens as effectively as full-length antibodies and are easy to clone and express. Because of their potential, VHHs are being intensively studied as potential therapeutic, diagnostic and imaging tools. The paper reviews the molecular background of heavy chain antibodies and describes methods of obtaining recombinant fragments of heavy chain antibodies as well as their therapeutic, diagnostic and other applications.

  4.  Variable fragments of heavy chain antibodies (VHHs: a new magic bullet molecule of medicine?

    Directory of Open Access Journals (Sweden)

    Dorota Smolarek

    2012-06-01

    Full Text Available  Serum of animals belonging to the Camelidae family (camels and llamas contains fully active antibodies that are naturally devoid of light chains. Variable domains derived from heavy chain antibodies (hcAb called VHHs or nanobodies™ can bind antigens as effectively as full-length antibodies and are easy to clone and express. Because of their potential, VHHs are being intensively studied as potential therapeutic, diagnostic and imaging tools. The paper reviews the molecular background of heavy chain antibodies and describes methods of obtaining recombinant fragments of heavy chain antibodies as well as their therapeutic, diagnostic and other applications.

  5. Acetylcholine receptor antibody

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood ...

  6. Antinuclear antibody panel

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003535.htm Antinuclear antibody panel To use the sharing features on this page, please enable JavaScript. The antinuclear antibody panel is a blood test that looks at ...

  7. Platelet antibodies blood test

    Science.gov (United States)

    This blood test shows if you have antibodies against platelets in your blood. Platelets are a part of the blood ... Chernecky CC, Berger BJ. Platelet antibody - blood. In: Chernecky ... caused by platelet destruction, hypersplenism, or hemodilution. ...

  8. Production of antibodies in plants: approaches and perspectives.

    Science.gov (United States)

    Ko, K; Brodzik, R; Steplewski, Z

    2009-01-01

    Advances in molecular biology, immunology, and plant biotechnology have changed the paradigm of plant as a food source to so-called plant bioreactor to produce valuable recombinant proteins. These include therapeutic or diagnostic monoclonal antibodies, vaccines, and other biopharmaceutical proteins. The plant as a bioreactor for the production of therapeutic proteins has several advantages, which include the lack of animal pathogenic contaminants, low cost of production, and ease of agricultural scale-up compared to other currently available systems. Thus, plants are considered to be a potential alternative to compete with other systems such as bacteria, yeast, or insect and mammalian cell culture. Plant production systems, particularly therapeutic antibodies, are very attractive to pharmaceutical companies to produce the antibodies in demand. Currently, we have successfully developed a plant system for production of anti-rabies monoclonal antibody and anti-colorectal cancer monoclonal antibody. The effective plant production system for recombinant antibodies requires the appropriate plant expression machinery with optimal combination of transgene expression regulatory elements, control of posttranslational protein processing, and efficient purification methods for product recovery. However, there are several limitations that have to be resolved to establish the efficient plant system for antibody production. Here, we discuss the approaches and perspectives in plant systems to produce monoclonal antibody.

  9. Antibody binding to p-Si using LANL SAM chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Aaron S [Los Alamos National Laboratory

    2010-12-06

    This NMSBA-sponsored project involves the attachment of antibodies to polymeric silicon (p-Si) surfaces, with the ultimate goal of attaching antibodies to nanowires for Vista Therapeutics, Inc. (Santa Fe, NM). This presentation describes the functionalization of p-Si surfaces. the activation of terminal carboxylates on these surfaces, the conjugation of antibodies, and the analyses undertaken at each step. The results of this work show that antibody conjugation is possible on p-Si coatings using the well-known EDC/NHS activation chemistry.

  10. Immunoprophylaxis in fish by injection of mouse antibody genes

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Cupit, P.M.; Einer-Jensen, Katja

    2000-01-01

    of infectious diseases. To test this in a fish model, a gene construct encoding a neutralizing single-chain antibody to the fish-pathogenic rhabdovirus VHSV (viral hemorrhagic septicemia virus) was administered to rainbow trout by intramuscular injection of plasmid DNA, Circulating recombinant antibodies could...... later be detected in the fish, and protective immunity to the viral disease was established.......Antibodies are a crucial part of the body's specific defense against infectious diseases and have considerable potential as therapeutic and prophylactic agents in humans and animals, The development of recombinant single-chain antibodies allows a genetic application strategy for prevention...

  11. Antibodies Against Melanin

    African Journals Online (AJOL)

    1973-01-06

    Jan 6, 1973 ... This study reports on unsuccessful attempts to produce antibodies against melanoprotein in rabbits. Available evidence suggests antibodies against melanocytes in the aetiology of vitiligo, but there is no convincing evidence for antibodies against melanin per se. It is suggested that the demonstration of ...

  12. Aggregates in monoclonal antibody manufacturing processes.

    Science.gov (United States)

    Vázquez-Rey, María; Lang, Dietmar A

    2011-07-01

    Monoclonal antibodies have proved to be a highly successful class of therapeutic products. Large-scale manufacturing of pharmaceutical antibodies is a complex activity that requires considerable effort in both process and analytical development. If a therapeutic protein cannot be stabilized adequately, it will lose partially or totally its therapeutic properties or even cause immunogenic reactions thus potentially further endangering the patients' health. The phenomenon of protein aggregation is a common issue that compromises the quality, safety, and efficacy of antibodies and can happen at different steps of the manufacturing process, including fermentation, purification, final formulation, and storage. Aggregate levels in drug substance and final drug product are a key factor when assessing quality attributes of the molecule, since aggregation might impact biological activity of the biopharmaceutical. In this review it is analyzed how aggregates are formed during monoclonal antibody industrial production, why they have to be removed and the manufacturing process steps that are designed to either minimize or remove aggregates in the final product. Copyright © 2011 Wiley Periodicals, Inc.

  13. Neutralization of botulinum neurotoxin by a human monoclonal antibody specific for the catalytic light chain.

    Directory of Open Access Journals (Sweden)

    Sharad P Adekar

    2008-08-01

    Full Text Available Botulinum neurotoxins (BoNT are a family of category A select bioterror agents and the most potent biological toxins known. Cloned antibody therapeutics hold considerable promise as BoNT therapeutics, but the therapeutic utility of antibodies that bind the BoNT light chain domain (LC, a metalloprotease that functions in the cytosol of cholinergic neurons, has not been thoroughly explored.We used an optimized hybridoma method to clone a fully human antibody specific for the LC of serotype A BoNT (BoNT/A. The 4LCA antibody demonstrated potent in vivo neutralization when administered alone and collaborated with an antibody specific for the HC. In Neuro-2a neuroblastoma cells, the 4LCA antibody prevented the cleavage of the BoNT/A proteolytic target, SNAP-25. Unlike an antibody specific for the HC, the 4LCA antibody did not block entry of BoNT/A into cultured cells. Instead, it was taken up into synaptic vesicles along with BoNT/A. The 4LCA antibody also directly inhibited BoNT/A catalytic activity in vitro.An antibody specific for the BoNT/A LC can potently inhibit BoNT/A in vivo and in vitro, using mechanisms not previously associated with BoNT-neutralizing antibodies. Antibodies specific for BoNT LC may be valuable components of an antibody antidote for BoNT exposure.

  14. Therapeutic misadventure.

    Science.gov (United States)

    Langford, N J

    2010-10-01

    Therapeutic misadventure can be defined as an injury or an adverse event caused by medical management rather than by an underlying disease. Within the National Health Service there were over 86,000 reported adverse incidents in 2007. In the USA medication errors have been rated as the fourth highest cause of death. Unfortunately one of the greatest contributors to iatrogenic injury is human error. The potential types of misadventure are infinite. Medication errors are a major part of this, being responsible for over 70% of cases that cause serious harm. However, many medication errors caused by slips, lapses, technical errors and mistakes are preventable; intentional violations of safe operating procedures are not. While medication errors were tolerated by society in the past, the readiness to institute criminal proceedings against health-care professionals has increased greatly in the UK over the last decade. The medication process consists of writing prescriptions, dispensing the product, administering it and monitoring its effects. Prescription errors arise owing to incomplete information, lack of appropriate labelling, environmental factors and human blunders. Even with a perfect prescription the right medication must be dispensed and appropriately labelled. Dispensing errors are not uncommon and may be compounded by non-clinical considerations. Administration of a drug by injection is one of the most dangerous aspects of the medication process, especially in inexperienced hands. The final component of medication supply is monitoring the effect of the medication. With short courses of medication such monitoring is easy, but with long-term medication, particularly with potent drugs where the margin between efficacy and toxicity is small, active procedures may be required to ensure toxicity does not ensue. Despite the endeavour of health-care professions to stick to the rule of 'first, do no harm', in reality this is difficult to achieve all of the time. When

  15. Mechanisms of monoclonal antibody stabilization and release from silk biomaterials

    Science.gov (United States)

    Guziewicz, Nicholas A.; Massetti, Andrew J.; Perez-Ramirez, Bernardo J.; Kaplan, David L.

    2013-01-01

    The availability of stabilization and sustained delivery systems for antibody therapeutics remains a major clinical challenge, despite the growing development of antibodies for a wide range of therapeutic applications due to their specificity and efficacy. A mechanistic understanding of protein-matrix interactions is critical for the development of such systems and is currently lacking as a mode to guide the field. We report mechanistic insight to address this need by using well-defined matrices based on silk gels, in combination with a monoclonal antibody. Variables including antibody loading, matrix density, charge interactions, hydrophobicity and water access were assessed to clarify mechanisms involved in the release of antibody from the biomaterial matrix. The results indicate that antibody release is primarily governed by hydrophobic interactions and hydration resistance, which are controlled by silk matrix chemistry, peptide domain distribution and protein density. Secondary ionic repulsions are also critical in antibody stabilization and release. Matrix modification by free methionine incorporation was found to be an effective strategy for mitigating encapsulation induced antibody oxidation. Additionally, these studies highlight a characterization approach to improve the understanding and development of other protein sustained delivery systems, with broad applicability to the rapidly developing monoclonal antibody field. PMID:23859659

  16. Differential Toxicity of Antibodies to the Prion Protein.

    Directory of Open Access Journals (Sweden)

    Regina R Reimann

    2016-01-01

    Full Text Available Antibodies against the prion protein PrPC can antagonize prion replication and neuroinvasion, and therefore hold promise as possible therapeutics against prion diseases. However, the safety profile of such antibodies is controversial. It was originally reported that the monoclonal antibody D13 exhibits strong target-related toxicity, yet a subsequent study contradicted these findings. We have reported that several antibodies against certain epitopes of PrPC, including antibody POM1, are profoundly neurotoxic, yet antibody ICSM18, with an epitope that overlaps with POM1, was reported to be innocuous when injected into mouse brains. In order to clarify this confusing situation, we assessed the neurotoxicity of antibodies D13 and ICSM18 with dose-escalation studies using diffusion-weighted magnetic resonance imaging and various histological techniques. We report that both D13 and ICSM18 induce rapid, dose-dependent, on-target neurotoxicity. We conclude that antibodies directed to this region may not be suitable as therapeutics. No such toxicity was found when antibodies against the flexible tail of PrPC were administered. Any attempt at immunotherapy or immunoprophylaxis of prion diseases should account for these potential untoward effects.

  17. Microbial platform technology for recombinant antibody fragment production: A review.

    Science.gov (United States)

    Gupta, Sanjeev Kumar; Shukla, Pratyoosh

    2017-02-01

    Recombinant antibody fragments are being used for the last few years as an important therapeutic protein to cure various critical and life threatening human diseases. Several expression platforms now days employed for the production of these recombinant fragments, out of which bacterial system has emerged a promising host for higher expression. Since, a small antibody fragment unlike full antibody does not require human-like post-translational modification therefore it is potentially expressed in prokaryotic production system. Recently, small antibody fragments such as scFvs (single-chain variable fragments) and Fabs (antibody fragments) which does not require glycosylation are successfully produced in bacteria and have commercially launched for therapeutic use as these fragments shows better tissue penetration and less immunogenic to human body compared to full-size antibody. Recently developed Wacker's ESETEC secretion technology is an efficient technology for the expression and secretion of the antibody fragment (Fab) exceeded up to 4.0 g/L while scFv up to 3.5 g/L into the fermentation broth. The Pfenex system and pOP prokaryotic expression vector are another platform used for the considerably good amount of antibody fragment production successfully. In this review, we summarize the recent progress on various expression platforms and cloning approaches for the production of different forms of antibody fragments in E. coli.

  18. Antibody-Based Therapies in Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Yu-Tzu Tai

    2011-01-01

    Full Text Available The unmet need for improved multiple myeloma (MM therapy has stimulated clinical development of monoclonal antibodies (mAbs targeting either MM cells or cells of the bone marrow (BM microenvironment. In contrast to small-molecule inhibitors, therapeutic mAbs present the potential to specifically target tumor cells and directly induce an immune response to lyse tumor cells. Unique immune-effector mechanisms are only triggered by therapeutic mAbs but not by small molecule targeting agents. Although therapeutic murine mAbs or chimeric mAbs can cause immunogenicity, the advancement of genetic recombination for humanizing rodent mAbs has allowed large-scale production and designation of mAbs with better affinities, efficient selection, decreasing immunogenicity, and improved effector functions. These advancements of antibody engineering technologies have largely overcome the critical obstacle of antibody immunogenicity and enabled the development and subsequent Food and Drug Administration (FDA approval of therapeutic Abs for cancer and other diseases.

  19. Functional optimization of agonistic antibodies to OX40 receptor with novel Fc mutations to promote antibody multimerization

    Science.gov (United States)

    Zhang, Di; Armstrong, Anthony A.; Luo, Jinquan; Chiu, Mark L.

    2017-01-01

    ABSTRACT Immunostimulatory receptors belonging to the tumor necrosis factor receptor (TNFR) superfamily are emerging as promising targets for cancer immunotherapies. To optimize the agonism of therapeutic antibodies to these receptors, Fc engineering of antibodies was applied to facilitate the clustering of cell surface TNFRs to activate downstream signaling pathways. One engineering strategy is to identify Fc mutations that facilitate antibody multimerization on the cell surface directly. From the analyses of the crystal packing of IgG1 structures, we identified a novel set of Fc mutations, T437R and K248E, that facilitated antibody multimerization upon binding to antigens on cell surface. In a NF-κB reporter assay, the engineered T437R/K248E mutations could facilitate enhanced agonism of an anti-OX40 antibody without the dependence on FcγRIIB crosslinking. Nonetheless, the presence of cells expressing FcγRIIB could facilitate a boost of the agonism of the engineered antibody with mutations on IgG1 Fc, but not on the silent IgG2σ Fc. The Fc engineered antibody also showed enhanced effector functions, including antibody-dependent cell-meditated cytotoxicity, antibody-dependent cellular phagocytosis, and complement-dependent cytotoxicity, depending on the IgG subtypes. Also, the engineered antibodies showed normal FcRn binding and pharmacokinetic profiles in mice. In summary, this study elucidated a novel Fc engineering approach to promote antibody multimerization on a cell surface, which could enhance agonism and improve effector function for anti-TNFR antibodies as well as other therapeutic antibodies. PMID:28758875

  20. Monoclonal antibodies: A review of therapeutic applications and ...

    African Journals Online (AJOL)

    the new mAbs are nearly ten-fold more potent compared to the recently described PG9, PG16 and VRC01 mAbs; and 100-fold more potent compared to the original prototype HIV broadly neutralizing mAbs [32]. ... (alpha-v/beta-3) present in blood vessels supplying tumors but is absent in blood vessels found in normal ...

  1. IL-8 as antibody therapeutic target in inflammatory diseases

    DEFF Research Database (Denmark)

    Skov, Lone; Beurskens, Frank J; Zachariae, Claus O C

    2008-01-01

    IL-8 is a chemokine that has been implicated in a number of inflammatory diseases involving neutrophil activation. HuMab 10F8 is a novel fully human mAb against IL-8, which binds a discontinuous epitope on IL-8 overlapping the receptor binding site, and which effectively neutralizes IL-8-dependen...

  2. Antibody-Mediated Internalization of Infectious HIV-1 Virions Differs among Antibody Isotypes and Subclasses

    Science.gov (United States)

    McRaven, Michael D; Sawant, Sheetal; Gurley, Thaddeus C; Xu, Thomas T.; Dennison, S. Moses; Liao, Hua-Xin; Chenine, Agnès-Laurence; Alam, S. Munir; Haynes, Barton F.; Tomaras, Georgia D.

    2016-01-01

    -induced antibodies and therapeutic antibodies will enable a better understanding of their capacity to prevent and/or control HIV-1 infection in vivo. PMID:27579713

  3. Progress and Challenges in the Design and Clinical Development of Antibodies for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Juan C. Almagro

    2018-01-01

    Full Text Available The remarkable progress in engineering and clinical development of therapeutic antibodies in the last 40 years, after the seminal work by Köhler and Milstein, has led to the approval by the United States Food and Drug Administration (FDA of 21 antibodies for cancer immunotherapy. We review here these approved antibodies, with emphasis on the methods used for their discovery, engineering, and optimization for therapeutic settings. These methods include antibody engineering via chimerization and humanization of non-human antibodies, as well as selection and further optimization of fully human antibodies isolated from human antibody phage-displayed libraries and immunization of transgenic mice capable of generating human antibodies. These technology platforms have progressively led to the development of therapeutic antibodies with higher human content and, thus, less immunogenicity. We also discuss the genetic engineering approaches that have allowed isotype switching and Fc modifications to modulate effector functions and bioavailability (half-life, which together with the technologies for engineering the Fv fragment, have been pivotal in generating more efficacious and better tolerated therapeutic antibodies to treat cancer.

  4. The emergence of antibody therapies for Ebola.

    Science.gov (United States)

    Hiatt, Andrew; Pauly, Michael; Whaley, Kevin; Qiu, Xiangguo; Kobinger, Gary; Zeitlin, Larry

    2015-12-23

    This review describes the history of Ebola monoclonal antibody (mAb) development leading up to the recent severe Ebola outbreak in West Africa. The Ebola virus has presented numerous perplexing challenges in the long effort to develop therapeutic antibody strategies. Since the first report of a neutralizing human anti-Ebola mAb in 1999, the straightforward progression from in vitro neutralization resulting in in vivo protection and therapy has not occurred. A number of mAbs, including the first reported, failed to protect non-human primates (NHPs) in spite of protection in rodents. An appreciation of the role of effector functions to antibody efficacy has contributed significantly to understanding mechanisms of in vivo protection. However a crucial contribution, as measured by post-exposure therapy of NHPs, involved the comprehensive testing of mAb cocktails. This effort was aided by the use of plant production technology where various combinations of mAbs could be rapidly produced and tested. Introduction of appropriate modifications, such as specific glycan profiles, also improved therapeutic efficacy. The resulting cocktail, ZMapp™, consists of three mAbs that were identified from numerous mAb candidates. ZMapp™ \\ is now being evaluated in human clinical trials but has already played a role in bringing awareness to the potential of antibody therapy for Ebola.

  5. Fixed Dosing of Monoclonal Antibodies in Oncology.

    Science.gov (United States)

    Hendrikx, Jeroen J M A; Haanen, John B A G; Voest, Emile E; Schellens, Jan H M; Huitema, Alwin D R; Beijnen, Jos H

    2017-10-01

    Most monoclonal antibodies in oncology are administered in body-size-based dosing schedules. This is believed to correct for variability in both drug distribution and elimination between patients. However, monoclonal antibodies typically distribute to the blood plasma and extracellular fluids only, which increase less than proportionally with the increase in body weight. Elimination takes place via proteolytic catabolism, a nonspecific immunoglobulin G elimination pathway, and intracellular degradation after binding to the target. The latter is the primary route of elimination and is related to target expression levels rather than body size. Taken together, the minor effects of body size on distribution and elimination of monoclonal antibodies and their usually wide therapeutic window do not support body-size-based dosing. We evaluated effects of body weight on volume of distribution and clearance of monoclonal antibodies in oncology and show that a fixed dose for most of these drugs is justified based on pharmacokinetics. A survey of the savings after fixed dosing of monoclonal antibodies at our hospital showed that fixed dosing can reduce costs of health care, especially when pooling of preparations is not possible (which is often the case in smaller hospitals). In conclusion, based on pharmacokinetic parameters of monoclonal antibodies, there is a rationale for fixed dosing of these drugs in oncology. Therefore, we believe that fixed dosing is justified and can improve efficiency of the compounding. Moreover, drug spillage can be reduced and medication errors may become less likely. The currently available knowledge of elimination of monoclonal antibodies combined with the publicly available data from clinical trials and extensive population pharmacokinetic (PopPK) modeling justifies fixed dosing. Interpatient variation in exposure is comparable after body weight and fixed dosing and most monoclonal antibodies show relatively flat dose-response relationships

  6. Therapeutic radionuclides: Making the right choice

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1996-08-01

    Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article.

  7. Recent advances in the construction of antibody-drug conjugates

    Science.gov (United States)

    Chudasama, Vijay; Maruani, Antoine; Caddick, Stephen

    2016-02-01

    Antibody-drug conjugates (ADCs) comprise antibodies covalently attached to highly potent drugs using a variety of conjugation technologies. As therapeutics, they combine the exquisite specificity of antibodies, enabling discrimination between healthy and diseased tissue, with the cell-killing ability of cytotoxic drugs. This powerful and exciting class of targeted therapy has shown considerable promise in the treatment of various cancers with two US Food and Drug Administration approved ADCs currently on the market (Adcetris and Kadcyla) and approximately 40 currently undergoing clinical evaluation. However, most of these ADCs exist as heterogeneous mixtures, which can result in a narrow therapeutic window and have major pharmacokinetic implications. In order for ADCs to deliver their full potential, sophisticated site-specific conjugation technologies to connect the drug to the antibody are vital. This Perspective discusses the strategies currently used for the site-specific construction of ADCs and appraises their merits and disadvantages.

  8. Marrow Derived Antibody Library for the Treatment of Neuroblastoma

    Science.gov (United States)

    2015-12-01

    specific antibodies for future therapeutic intent. 3 Body of Work This is the final technical report for grant title with “Marrow-derived Antibody...immunofluorescence intensity on 3% PFA fixed attached whole cells from the low passage cell line cultured in 96 well plates or histological sections of a...al., Phage-display selection on tumor histological specimens with laser capture microdissection. J Immunol Methods, 2009. 347(1-2): p. 46-53.

  9. Warm antibody autoimmune hemolytic anemia.

    Science.gov (United States)

    Kalfa, Theodosia A

    2016-12-02

    Autoimmune hemolytic anemia (AIHA) is a rare and heterogeneous disease that affects 1 to 3/100 000 patients per year. AIHA caused by warm autoantibodies (w-AIHA), ie, antibodies that react with their antigens on the red blood cell optimally at 37°C, is the most common type, comprising ∼70% to 80% of all adult cases and ∼50% of pediatric cases. About half of the w-AIHA cases are called primary because no specific etiology can be found, whereas the rest are secondary to other recognizable underlying disorders. This review will focus on the postulated immunopathogenetic mechanisms in idiopathic and secondary w-AIHA and report on the rare cases of direct antiglobulin test-negative AIHA, which are even more likely to be fatal because of inherent characteristics of the causative antibodies, as well as because of delays in diagnosis and initiation of appropriate treatment. Then, the characteristics of w-AIHA associated with genetically defined immune dysregulation disorders and special considerations on its management will be discussed. Finally, the standard treatment options and newer therapeutic approaches for this chronic autoimmune blood disorder will be reviewed. © 2016 by The American Society of Hematology. All rights reserved.

  10. Antibody engineering: methods and protocols

    National Research Council Canada - National Science Library

    Chames, Patrick

    2012-01-01

    "Antibody Engineering: Methods and Protocols, Second Edition was compiled to give complete and easy access to a variety of antibody engineering techniques, starting from the creation of antibody repertoires and efficient...

  11. Anti-insulin antibody test

    Science.gov (United States)

    Insulin antibodies - serum; Insulin Ab test; Insulin resistance - insulin antibodies; Diabetes - insulin antibodies ... You appear to have an allergic response to insulin Insulin no longer seems to control your diabetes

  12. Pre-existing Antibody: Biotherapeutic Modality-Based Review.

    Science.gov (United States)

    Gorovits, Boris; Clements-Egan, Adrienne; Birchler, Mary; Liang, Meina; Myler, Heather; Peng, Kun; Purushothama, Shobha; Rajadhyaksha, Manoj; Salazar-Fontana, Laura; Sung, Crystal; Xue, Li

    2016-03-01

    Pre-existing antibodies to biotherapeutic drugs have been detected in drug-naïve subjects for a variety of biotherapeutic modalities. Pre-existing antibodies are immunoglobulins that are either specific or cross-reacting with a protein or glycan epitopes on a biotherapeutic compound. Although the exact cause for pre-existing antibodies is often unknown, environmental exposures to non-human proteins, glycans, and structurally similar products are frequently proposed as factors. Clinical consequences of the pre-existing antibodies vary from an adverse effect on patient safety to no impact at all and remain highly dependent on the biotherapeutic drug modality and therapeutic indication. As such, pre-existing antibodies are viewed as an immunogenicity risk factor requiring a careful evaluation. Herein, the relationships between biotherapeutic modalities to the nature, prevalence, and clinical consequences of pre-existing antibodies are reviewed. Initial evidence for pre-existing antibody is often identified during anti-drug antibody (ADA) assay development. Other interfering factors known to cause false ADA positive signal, including circulating multimeric drug target, rheumatoid factors, and heterophilic antibodies, are discussed.

  13. Strategies for enhancing antibody delivery to the brain.

    Science.gov (United States)

    Frank, Richard T; Aboody, Karen S; Najbauer, Joseph

    2011-12-01

    Antibodies and antibody conjugates have emerged as important tools for cancer therapy. However, a major therapeutic challenge for the use of antibodies is their inability to cross the blood-brain barrier (BBB) to reach tumors localized in the central nervous system (CNS). Multiple methods have been developed to enhance antibody delivery to the CNS, including direct injection, mechanical or biochemical disruption of the BBB, conjugation to a 'molecular Trojan horse', cationization, encapsulation in nanoparticles and liposomes, and more recently, stem cell-mediated antibody delivery. In this review, we discuss each of these approaches, highlighting their successes and the obstacles that remain to be overcome. Copyright © 2011. Published by Elsevier B.V.

  14. Antiviral Therapy by HIV-1 Broadly Neutralizing and Inhibitory Antibodies

    Directory of Open Access Journals (Sweden)

    Zhiqing Zhang

    2016-11-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection causes acquired immune deficiency syndrome (AIDS, a global epidemic for more than three decades. HIV-1 replication is primarily controlled through antiretroviral therapy (ART but this treatment does not cure HIV-1 infection. Furthermore, there is increasing viral resistance to ART, and side effects associated with long-term therapy. Consequently, there is a need of alternative candidates for HIV-1 prevention and therapy. Recent advances have discovered multiple broadly neutralizing antibodies against HIV-1. In this review, we describe the key epitopes on the HIV-1 Env protein and the reciprocal broadly neutralizing antibodies, and discuss the ongoing clinical trials of broadly neutralizing and inhibitory antibody therapy as well as antibody combinations, bispecific antibodies, and methods that improve therapeutic efficacy by combining broadly neutralizing antibodies (bNAbs with latency reversing agents. Compared with ART, HIV-1 therapeutics that incorporate these broadly neutralizing and inhibitory antibodies offer the advantage of decreasing virus load and clearing infected cells, which is a promising prospect in HIV-1 prevention and treatment.

  15. Recent Advances in Monoclonal Antibody Therapies for Multiple Sclerosis.

    Science.gov (United States)

    Wootla, Bharath; Watzlawik, Jens O; Stavropoulos, Nikolaos; Wittenberg, Nathan J; Dasari, Harika; Abdelrahim, Murtada A; Henley, John R; Oh, Sang-Hyun; Warrington, Arthur E; Rodriguez, Moses

    2016-06-01

    Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating disease of the CNS and results in neurological disability. Existing immunomodulatory and immunosuppressive approaches lower the number of relapses but do not cure or reverse existing deficits nor improve long-term disability in MS patients. Monogenic antibodies were described as treatment options for MS, however the immunogenicity of mouse antibodies hampered the efficacy of potential therapeutics in humans. Availability of improved antibody production technologies resulted in a paradigm shift in MS treatment strategies. In this review, an overview of immunotherapies for MS that use conventional monoclonal antibodies reactive to immune system and their properties and mechanisms of action will be discussed, including recent advances in MS therapeutics and highlight natural autoantibodies (NAbs) that directly target CNS cells. Recent challenges for MS therapy are the identification of relevant molecular and cellular targets, time frame of treatment, and antibody toxicity profiles to identify safe treatment options for MS patients. The application of monoclonal antibody therapies with better biological efficacy associated with minimum side effects possesses huge clinical potential. Advances in monoclonal antibody technologies that directly target cells of nervous system may promote the CNS regeneration field from bench to bedside.

  16. Recent Advances in Monoclonal Antibody Therapies for Multiple Sclerosis

    Science.gov (United States)

    Stavropoulos, Nikolaos; Wittenberg, Nathan J.; Dasari, Harika; Abdelrahim, Murtada A.; Henley, John R.; Oh, Sang-Hyun; Warrington, Arthur E.; Rodriguez, Moses

    2016-01-01

    Introduction Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating disease of the CNS and results in neurological disability. Existing immunomodulatory and immunosuppressive approaches lower the number of relapses but do not cure or reverse existing deficits nor improve long-term disability in MS patients. Areas Covered Monogenic antibodies were described as treatment options for MS, however the immunogenicity of mouse antibodies hampered the efficacy of potential therapeutics in humans. Availability of improved antibody production technologies resulted in a paradigm shift in MS treatment strategies. In this review, an overview of immunotherapies for MS that use conventional monoclonal antibodies reactive to immune system and their properties and mechanisms of action will be discussed, including recent advances in MS therapeutics and highlight natural autoantibodies (NAbs) that directly target CNS cells. Expert Opinion Recent challenges for MS therapy are the identification of relevant molecular and cellular targets, time frame of treatment, and antibody toxicity profiles to identify safe treatment options for MS patients. The application of monoclonal antibody therapies with better biological efficacy associated with minimum side effects possesses huge clinical potential. Advances in monoclonal antibody technologies that directly target cells of nervous system may promote the CNS regeneration field from bench to bedside. PMID:26914737

  17. Monoclonal antibody "gold rush".

    Science.gov (United States)

    Maggon, Krishan

    2007-01-01

    The market, sales and regulatory approval of new human medicines, during the past few years, indicates increasing number and share of new biologics and emergence of new multibillion dollar molecules. The global sale of monoclonal antibodies in 2006 were $20.6 billion. Remicade had annual sales gain of $1 billion during the past 3 years and five brands had similar increase in 2006. Rituxan with 2006 sales of $4.7 billion was the best selling monoclonal antibody and biological product and the 6th among the top selling medicinal brand. It may be the first biologic and monoclonal antibody to reach $10 billion annual sales in the near future. The strong demand from cancer and arthritis patients has surpassed almost all commercial market research reports and sales forecast. Seven monoclonal antibody brands in 2006 had sales exceeding $1 billion. Humanized or fully human monoclonal antibodies with low immunogenicity, enhanced antigen binding and reduced cellular toxicity provide better clinical efficacy. The higher technical and clinical success rate, overcoming of technical hurdles in large scale manufacturing, low cost of market entry and IND filing, use of fully human and humanized monoclonal antibodies has attracted funds and resources towards R&D. Review of industry research pipeline and sales data during the past 3 years indicate a real paradigm shift in industrial R&D from pharmaceutical to biologics and monoclonal antibodies. The antibody bandwagon has been joined by 200 companies with hundreds of new projects and targets and has attracted billions of dollars in R&D investment, acquisitions and licensing deals leading to the current Monoclonal Antibody Gold Rush.

  18. Dual antibody therapy to harness the innate anti-tumor immune response to enhance antibody targeting of tumors.

    Science.gov (United States)

    Chester, Cariad; Marabelle, Aurelien; Houot, Roch; Kohrt, Holbrook E

    2015-04-01

    Cancer immunotherapy is a rapidly evolving field that offers a novel paradigm for cancer treatment: therapies focus on enhancing the immune system's innate and adaptive anti-tumor response. Early immunotherapeutics have achieved impressive clinical outcomes and monoclonal antibodies are now integral to therapeutic strategies in a variety of cancers. However, only recently have antibodies targeting innate immune cells entered clinical development. Innate immune effector cells play important roles in generating and maintaining antitumor immunity. Antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) are important innate immune mechanisms for tumor eradication. These cytolytic processes are initiated by the detection of a tumor-targeting antibody and can be augmented by activating co-stimulatory pathways or blocking inhibitory signals on innate immune cells. The combination of FDA-approved monoclonal antibodies with innate effector-targeting antibodies has demonstrated potent preclinical therapeutic synergy and early-phase combinatorial clinical trials are ongoing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Productive common light chain libraries yield diverse panels of high affinity bispecific antibodies

    Science.gov (United States)

    Van Blarcom, Thomas; Melton, Zea; Cheung, Wai Ling; Wagstrom, Chris; McDonough, Dan; Valle Oseguera, Cendy; Ding, Sheng; Rossi, Andrea; Potluri, Shobha; Sundar, Purnima; Sirota, Marina; Yan, Yu; Jones, Jeffrey; Roe-Zurz, Zygy; Srivatsa Srinivasan, Surabhi; Zhai, Wenwu; Pons, Jaume; Rajpal, Arvind; Chaparro-Riggers, Javier

    2018-01-01

    ABSTRACT The commercial success of bispecific antibodies generally has been hindered by the complexities associated with generating appropriate molecules for both research scale and large scale manufacturing purposes. Bispecific IgG (BsIgG) based on two antibodies that use an identical common light chain can be combined with a minimal set of Fc mutations to drive heavy chain heterodimerization in order to address these challenges. However, the facile generation of common light chain antibodies with properties similar to traditional monoclonal antibodies has not been demonstrated and they have only been used sparingly. Here, we describe the design of a synthetic human antibody library based on common light chains to generate antibodies with biochemical and biophysical properties that are indistinguishable to traditional therapeutic monoclonal antibodies. We used this library to generate diverse panels of well-behaved, high affinity antibodies toward a variety of epitopes across multiple antigens, including mouse 4-1BB, a therapeutically important T cell costimulatory receptor. Over 200 BsIgG toward 4-1BB were generated using an automated purification method we developed that enables milligram-scale production of BsIgG. This approach allowed us to identify antibodies with a wide range of agonistic activity that are being used to further investigate the therapeutic potential of antibodies targeting one or more epitopes of 4-1BB. PMID:29227213

  20. Host modulation by therapeutic agents

    Directory of Open Access Journals (Sweden)

    Sugumari Elavarasu

    2012-01-01

    Full Text Available Periodontal disease susceptible group present advanced periodontal breakdown even though they achieve a high standard of oral hygiene. Various destructive enzymes and inflammatory mediators are involved in destruction. These are elevated in case of periodontal destruction. Host modulation aims at bringing these enzymes and mediators to normal level. Doxycycline, nonsteroidal anti-inflammatory drugs (NSAIDs, bisphosphonates, nitrous oxide (NO synthase inhibitors, recombinant human interleukin-11 (rhIL-11, omega-3 fatty acid, mouse anti-human interleukin-6 receptor antibody (MRA, mitogen-activated protein kinase (MAPK inhibitors, nuclear factor-kappa B (NF-kb inhibitors, osteoprotegerin, and tumor necrosis factor antagonist (TNF-α are some of the therapeutic agents that have host modulation properties.

  1. Antithyroid microsomal antibody

    Science.gov (United States)

    ... to confirm the cause of thyroid problems, including Hashimoto thyroiditis . The test is also used to find ... positive test may be due to: Granulomatous thyroiditis Hashimoto thyroiditis High levels of these antibodies have also ...

  2. Serum herpes simplex antibodies

    Science.gov (United States)

    ... causes cold sores (oral herpes). HSV-2 causes genital herpes. How the Test is Performed A blood sample ... person has ever been infected with oral or genital herpes . It looks for antibodies to herpes simplex virus ...

  3. ANA (Antinuclear Antibody Test)

    Science.gov (United States)

    ... Testing Leptin Levetiracetam Lipase Lipid Profile Lipoprotein (a) Lithium Liver Panel Lp-PLA2 Lupus Anticoagulant Testing Luteinizing ... Scleroderma Elsewhere On The Web Lupus Foundation of America American College of Rheumatology: Antinuclear Antibodies (ANA) American ...

  4. Anti-sulfotyrosine antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Bertozzi, Carolyn R [Berkeley, CA; Kehoe, John [Saint Davids, PA; Bradbury, Andrew M [Santa Fe, NM

    2009-09-15

    The invention provides anti-sulfotyrosine specific antibodies capable of detecting and isolating polypeptides that are tyrosine-sulfated. The sulfotyrosine antibodies and antibody fragments of the invention may be used to discriminate between the non-sulfated and sulfated forms of such proteins, using any number of immunological assays, such ELISAs, immunoblots, Western Blots, immunoprecipitations, and the like. Using a phage-display system, single chain antibodies (scFvs) were generated and screened against tyrosine-sulfated synthetic peptide antigens, resulting in the isolation of scFvs that specifically recognize sulfotyrosine-containing peptides and/or demonstrate sulfotyrosine-specific binding in tyrosine sulfated proteins. The VH and VL genes from one such sulfotyrosine-specific scFv were employed to generate a full length, sulfotyrosine-specific immunoglobulin.

  5. Antibody Blood Tests

    Science.gov (United States)

    Antibody Blood Tests Researchers have discovered that people with celiac disease who eat gluten have higher than normal levels of ... do I do if I have a negative blood test (or panel) but I’m still having symptoms? ...

  6. Expression of Recombinant Vaccines and Antibodies in Plants

    OpenAIRE

    Ko, Kisung

    2014-01-01

    Plants are able to perform post-translational maturations of therapeutic proteins required for their functional biological activity and suitable in vivo pharmacokinetics. Plants can be a low-cost, large-scale production platform of recombinant biopharmaceutical proteins such as vaccines and antibodies. Plants, however, lack mechanisms of processing authentic human N-glycosylation, which imposes a major limitation in their use as an expression system for therapeutic glycoproducts. Efforts have...

  7. Antigen-Specific Monoclonal Antibodies Isolated from B Cells Expressing Constitutively Active STAT5

    NARCIS (Netherlands)

    Scheeren, F.A.; van Geelen, C.M.M.; Yasuda, E.; Spits, H.; Beaumont, T.

    2011-01-01

    Background: Fully human monoclonal antibodies directed against specific pathogens have a high therapeutic potential, but are difficult to generate. Methodology/Principal Findings: Memory B cells were immortalized by expressing an inducible active mutant of the transcription factor Signal Transducer

  8. Human Antibodies Against Middle East Respiratory Syndrome Coronavirus | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The National Cancer Institute is seeking statements of capability or interest from parties interested in collaborative research to co-develop antibody-based therapeutic against MERS-CoV, including animal studies, cGMP manufacturing, and clinical trials.

  9. Human antibody production in transgenic animals.

    Science.gov (United States)

    Brüggemann, Marianne; Osborn, Michael J; Ma, Biao; Hayre, Jasvinder; Avis, Suzanne; Lundstrom, Brian; Buelow, Roland

    2015-04-01

    Fully human antibodies from transgenic animals account for an increasing number of new therapeutics. After immunization, diverse human monoclonal antibodies of high affinity can be obtained from transgenic rodents, while large animals, such as transchromosomic cattle, have produced respectable amounts of specific human immunoglobulin (Ig) in serum. Several strategies to derive animals expressing human antibody repertoires have been successful. In rodents, gene loci on bacterial artificial chromosomes or yeast artificial chromosomes were integrated by oocyte microinjection or transfection of embryonic stem (ES) cells, while ruminants were derived from manipulated fibroblasts with integrated human chromosome fragments or human artificial chromosomes. In all strains, the endogenous Ig loci have been silenced by gene targeting, either in ES or fibroblast cells, or by zinc finger technology via DNA microinjection; this was essential for optimal production. However, comparisons showed that fully human antibodies were not as efficiently produced as wild-type Ig. This suboptimal performance, with respect to immune response and antibody yield, was attributed to imperfect interaction of the human constant region with endogenous signaling components such as the Igα/β in mouse, rat or cattle. Significant improvements were obtained when the human V-region genes were linked to the endogenous CH-region, either on large constructs or, separately, by site-specific integration, which could also silence the endogenous Ig locus by gene replacement or inversion. In animals with knocked-out endogenous Ig loci and integrated large IgH loci, containing many human Vs, all D and all J segments linked to endogenous C genes, highly diverse human antibody production similar to normal animals was obtained.

  10. Development of Biodegradable Nanocarriers Loaded with a Monoclonal Antibody

    Directory of Open Access Journals (Sweden)

    Andrew Gdowski

    2015-02-01

    Full Text Available Treatments utilizing monoclonal antibody therapeutics against intracellular protein-protein interactions in cancer cells have been hampered by several factors, including poor intracellular uptake and rapid lysosomal degradation. Our current work examines the feasibility of encapsulating monoclonal antibodies within poly(lactic-co-glycolic acid (PLGA nanoparticles using a water/oil/water double emulsion solvent evaporation technique. This method can be used to prepare protective polymeric nanoparticles for transporting functional antibodies to the cytoplasmic compartment of cancer cells. Nanoparticles were formulated and then characterized using a number of physical and biological parameters. The average nanoparticle size ranged from 221 to 252 nm with a low polydispersity index. Encapsulation efficiency of 16%–22% and antibody loading of 0.3%–1.12% were observed. The antibody molecules were released from the nanoparticles in a sustained manner and upon release maintained functionality. Our studies achieved successful formulation of antibody loaded polymeric nanoparticles, thus indicating that a PLGA-based antibody nanoformulation is a promising intracellular delivery vehicle for a large number of new intracellular antibody targets in cancer cells.

  11. From Monoclonal Antibodies to Chimeric Antigen Receptors for the Treatment of Human Malignancies

    OpenAIRE

    Caruana, Ignazio; Diaconu, Iulia; Dotti, Gianpietro

    2014-01-01

    Monoclonal antibodies (mAbs) and their directly derived cell-based application known as chimeric antigen receptors (CARs) ensue from the need to develop novel therapeutic strategies that retain high anti-tumor activity, but carry reduced toxicity compared to conventional chemo- and radio-therapies. In this concise review article we will summarize the application of antibodies designed to target antigens expressed by tumor cells, and the transition from these antibodies to the generation of CARs.

  12. A LAIR-1 insertion generates broadly reactive antibodies against malaria variant antigens

    OpenAIRE

    Tan, Joshua; Pieper, Kathrin; Piccoli, Luca; Abdi, Abdirahman; Perez, Mathilde Foglierini; Geiger, Roger; Tully, Claire Maria; Jarrossay, David; Maina Ndungu, Francis; Wambua, Juliana; Bejon, Philip; Fregni, Chiara Silacci; Fernandez-Rodriguez, Blanca; Barbieri, Sonia; Bianchi, Siro

    2015-01-01

    Plasmodium falciparum antigens expressed on the surface of infected erythrocytes are important targets of naturally acquired immunity against malaria, but their high number and variability provide the pathogen with a powerful means of escape from host antibodies 1?4 . Although broadly reactive antibodies against these antigens could be useful as therapeutics and in vaccine design, their identification has proven elusive. Here, we report the isolation of human monoclonal antibodies that recogn...

  13. Sustained systemic delivery of monoclonal antibodies by genetically modified skin fibroblasts

    DEFF Research Database (Denmark)

    Noël, D; Pelegrin, M; Brockly, F

    2000-01-01

    In vivo production and systemic delivery of therapeutic antibodies by engineered cells might advantageously replace injection of purified antibodies for treating a variety of life-threatening diseases, including cancer, acquired immunodeficiency syndrome, and autoimmune diseases. We report here t....... This supports the notion that skin fibroblasts can potentially be used in antibody-based gene/cell therapy protocols without inducing any adverse immune response in treated individuals....

  14. In-depth analysis of subclass-specific conformational preferences of IgG antibodies

    DEFF Research Database (Denmark)

    Tian, Xinsheng; Vestergaard, Bente; Thorolfsson, Matthias

    2015-01-01

    with identical variable regions, were thoroughly analysed by the ensemble optimization method. The extended analysis of the optimized ensembles through shape clustering reveals distinct subclass-specific conformational preferences, which provide new insights for understanding the variations in physical....../chemical stability and biological function of therapeutic antibodies. Importantly, the way that specific differences in the linker region correlate with the solution structure of intact antibodies is revealed, thereby visualizing future potential for the rational design of antibodies with designated physicochemical...

  15. Single Domain Antibodies as New Biomarker Detectors

    Directory of Open Access Journals (Sweden)

    Chiuan Herng Leow

    2017-10-01

    Full Text Available Biomarkers are defined as indicators of biological processes, pathogenic processes, or pharmacological responses to a therapeutic intervention. Biomarkers have been widely used for early detection, prediction of response after treatment, and for monitoring the progression of diseases. Antibodies represent promising tools for recognition of biomarkers, and are widely deployed as analytical tools in clinical settings. For immunodiagnostics, antibodies are now exploited as binders for antigens of interest across a range of platforms. More recently, the discovery of antibody surface display and combinatorial chemistry techniques has allowed the exploration of new binders from a range of animals, for instance variable domains of new antigen receptors (VNAR from shark and variable heavy chain domains (VHH or nanobodies from camelids. These single domain antibodies (sdAbs have some advantages over conventional murine immunoglobulin owing to the lack of a light chain, making them the smallest natural biomarker binders thus far identified. In this review, we will discuss several biomarkers used as a means to validate diseases progress. The potential functionality of modern singe domain antigen binders derived from phylogenetically early animals as new biomarker detectors for current diagnostic and research platforms development will be described.

  16. Neurological manifestations of systemic lupus erythematosus: role of antiphospholipid antibodies.

    Science.gov (United States)

    Golstein, M; Meyer, O; Bourgeois, P; Palazzo, E; Nicaise, P; Labarre, C; Kahn, M F

    1993-01-01

    Antiphospholipid antibodies (APL) are associated with venous and arterial thrombosis in SLE patients. Various thrombotic and non-thrombotic neurological manifestations have been reported in SLE but whether or not they are related to the presence of APL antibodies remains uncertain. To assess the possible association between neurological involvement in SLE and APL antibodies, IgG anticardiolipin antibodies (IgG ACL) were looked for using an ELISA technique in 92 consecutive SLE patients seen over a one-year period. Other APL determinations included VDRL and lupus anticoagulant (LAC) testing using APTT and the diluted thromboplastin time. Twenty-four SLE patients presented with neurological manifestations (40 episodes): 15/24 (62.5%) were found positive for APL antibodies (11 VDRL, 8 LAC, 7 ACL antibodies) versus 22/68 patients (32%) without neurological symptoms (p < 0.01). APL antibodies antedated neurological symptoms in 13/16 cases. Neurological manifestations were subsequently divided into 3 groups: thrombotic (n = 14), psychosis and convulsions (n = 15), miscellaneous (n = 10). No correlation was found between APL antibodies and any of the 3 subgroups. Among patients with neurological SLE, APL antibodies were present in two with valvular heart disease, as well as in seven with a history of either deep vein thrombosis, livedo reticularis or miscarriage. Among 7 patients with thrombocytopenia and neurological symptoms, 6 had APL antibodies. These data suggest that APL syndrome is associated with neuro-ophthalmological manifestations of SLE regardless of whether or not the mechanism of neurological involvement is thrombotic. SLE patients with APL antibodies may be at risk for future neurological manifestations. However, it is still questionable that APL positivity has definite therapeutic consequences.

  17. High-content analysis of antibody phage-display library selection outputs identifies tumor selective macropinocytosis-dependent rapidly internalizing antibodies.

    Science.gov (United States)

    Ha, Kevin D; Bidlingmaier, Scott M; Zhang, Yafeng; Su, Yang; Liu, Bin

    2014-12-01

    Many forms of antibody-based targeted therapeutics, including antibody drug conjugates, utilize the internalizing function of the targeting antibody to gain intracellular entry into tumor cells. Ideal antibodies for developing such therapeutics should be capable of both tumor-selective binding and efficient endocytosis. The macropinocytosis pathway is capable of both rapid and bulk endocytosis, and recent studies have demonstrated that it is selectively up-regulated by cancer cells. We hypothesize that receptor-dependent macropinocytosis can be achieved using tumor-targeting antibodies that internalize via the macropinocytosis pathway, improving potency and selectivity of the antibody-based targeted therapeutic. Although phage antibody display libraries have been utilized to find antibodies that bind and internalize to target cells, no methods have been described to screen for antibodies that internalize specifically via macropinocytosis. We hereby describe a novel screening strategy to identify phage antibodies that bind and rapidly enter tumor cells via macropinocytosis. We utilized an automated microscopic imaging-based, High Content Analysis platform to identify novel internalizing phage antibodies that colocalize with macropinocytic markers from antibody libraries that we have generated previously by laser capture microdissection-based selection, which are enriched for internalizing antibodies binding to tumor cells in situ residing in their tissue microenvironment (Ruan, W., Sassoon, A., An, F., Simko, J. P., and Liu, B. (2006) Identification of clinically significant tumor antigens by selecting phage antibody library on tumor cells in situ using laser capture microdissection. Mol. Cell. Proteomics. 5, 2364-2373). Full-length human IgG molecules derived from macropinocytosing phage antibodies retained the ability to internalize via macropinocytosis, validating our screening strategy. The target antigen for a cross-species binding antibody with a highly active

  18. High-content Analysis of Antibody Phage-display Library Selection Outputs Identifies Tumor Selective Macropinocytosis-dependent Rapidly Internalizing Antibodies*

    Science.gov (United States)

    Ha, Kevin D.; Bidlingmaier, Scott M.; Zhang, Yafeng; Su, Yang; Liu, Bin

    2014-01-01

    Many forms of antibody-based targeted therapeutics, including antibody drug conjugates, utilize the internalizing function of the targeting antibody to gain intracellular entry into tumor cells. Ideal antibodies for developing such therapeutics should be capable of both tumor-selective binding and efficient endocytosis. The macropinocytosis pathway is capable of both rapid and bulk endocytosis, and recent studies have demonstrated that it is selectively up-regulated by cancer cells. We hypothesize that receptor-dependent macropinocytosis can be achieved using tumor-targeting antibodies that internalize via the macropinocytosis pathway, improving potency and selectivity of the antibody-based targeted therapeutic. Although phage antibody display libraries have been utilized to find antibodies that bind and internalize to target cells, no methods have been described to screen for antibodies that internalize specifically via macropinocytosis. We hereby describe a novel screening strategy to identify phage antibodies that bind and rapidly enter tumor cells via macropinocytosis. We utilized an automated microscopic imaging-based, High Content Analysis platform to identify novel internalizing phage antibodies that colocalize with macropinocytic markers from antibody libraries that we have generated previously by laser capture microdissection-based selection, which are enriched for internalizing antibodies binding to tumor cells in situ residing in their tissue microenvironment (Ruan, W., Sassoon, A., An, F., Simko, J. P., and Liu, B. (2006) Identification of clinically significant tumor antigens by selecting phage antibody library on tumor cells in situ using laser capture microdissection. Mol. Cell. Proteomics. 5, 2364–2373). Full-length human IgG molecules derived from macropinocytosing phage antibodies retained the ability to internalize via macropinocytosis, validating our screening strategy. The target antigen for a cross-species binding antibody with a highly

  19. Radiolabeled antibodies and RGD-peptides for the treatment of ovarian cancer

    NARCIS (Netherlands)

    Janssen, M.L.H.

    2004-01-01

    In this thesis, preclinical studies on new treatment modalities for ovarian cancer are descibed, applying radiolabeled antibodies and radiolabeled RGD-peptides. In chapter 2 a study is described comparing the therapeutic efficacy of the antibody HMFG1 radiolabeled with several beta-emitting

  20. Monoclonal Antibodies Follow Distinct Aggregation Pathways During Production-Relevant Acidic Incubation and Neutralization

    DEFF Research Database (Denmark)

    Pedersen, Thomas Skamris; Tian, Xinsheng; Thorolfsson, Matthias

    2016-01-01

    PURPOSE: Aggregation aspects of therapeutic monoclonal antibodies (mAbs) are of common concern to the pharmaceutical industry. Low pH treatment is applied during affinity purification and to inactivate endogenous retroviruses, directing interest to the mechanisms of acid-induced antibody aggregat...

  1. Immuno-PET : A navigator in monoclonal antibody development and applications

    NARCIS (Netherlands)

    van Dongen, Guus A. M. S.; Visser, Gerard W. M.; Hooge, Marjolijn N. Lub-de; Perk, Lars R.; de Vries, Elisabeth G. E.

    2007-01-01

    Monoclonal antibodies (mAbs) have been approved for use as diagnostics and therapeutics in a broad range of medical indications, but especially in oncology. In addition, hundreds of new mAbs, engineered mAb fragments, and nontraditional antibody-like scaffolds directed against either validated or

  2. Animal models of antineutrophil cytoplasm antibody-associated vasculitis.

    LENUS (Irish Health Repository)

    Salama, Alan D

    2012-01-01

    To provide an update on the experimental models that have been developed recapitulating clinical antineutrophil cytoplasm antibody (ANCA) associated vasculitis. The application of the models in the study of pathogenesis, and the therapeutic implications of this, are covered in the article by van Timmeren and Heeringa in this issue.

  3. Antinucleosome antibodies as early predictors of lupus nephritis ...

    African Journals Online (AJOL)

    Background: The role of the nucleosome in the induction of antibody response in lupus mediated tissue damage especially glomerulonephritis, may provide a new insight in the early diagnosis and alternative therapeutic developments in systemic lupus erythematosus (SLE). Objectives: To evaluate the frequency and ...

  4. Natural and Man-made Antibody Repertories for Antibody Discovery

    Directory of Open Access Journals (Sweden)

    Juan C eAlmagro

    2012-11-01

    Full Text Available Antibodies are the fastest-growing segment of the biologics market. The success of antibody-based drugs resides in their exquisite specificity, high potency, stability, solubility, safety and relatively inexpensive manufacturing process in comparison with other biologics. We outline here the structural studies and fundamental principles that define how antibodies interact with diverse targets. We also describe the antibody repertoires and affinity maturation mechanisms of human, mice and chickens, plus the use of novel single-domain antibodies in camelids and sharks. These species all utilize diverse evolutionary solutions to generate specific and high affinity antibodies and illustrate the plasticity of natural antibody repertoires. In addition, we discuss the multiple variations of man-made antibody repertoires designed and validated in the last two decades, which have served as tools to explore how the size, diversity and composition of a repertoire impact the antibody discovery process.

  5. Recent developments in monoclonal antibody radiolabeling techniques

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.; Mease, R.C.

    1989-01-01

    Monoclonal antibodies (MAbs) have shown the potential to serve as selective carriers of radionuclides to specific in vivo antigens. Accordingly, there has been an intense surge of research activity in an effort to develop and evaluate MAb-based radiopharmaceuticals for tumor imaging (radioimmunoscintigraphy) and therapy (radioimmunotherapy), as well as for diagnosing nonmalignant diseases. A number of problems have recently been identified, related to the MAbs themselves and to radiolabeling techniques, that comprise both the selectivity and the specificity of the in vivo distribution of radiolabeled MAbs. This paper will address some of these issues and primarily discuss recent developments in the techniques for radiolabeling monoclonal antibodies that may help resolve problems related to the poor in vivo stability of the radiolabel and may thus produce improved biodistribution. Even though many issues are identical with therapeutic radionuclides, the discussion will focus mainly on radioimmunoscintigraphic labels. 78 refs., 6 tabs.

  6. Monoclonal Antibodies production technology

    Directory of Open Access Journals (Sweden)

    Flávia Rocha

    2011-02-01

    Full Text Available Since the first cells were capable of maintain a continuous antibody supply, developed by Köhler and Milstein in 1975, its use in medicine and industry showed a great potential. New researches were developed to enhance the use of such cells, including immunizations, mieloma cells, fusion methodology, screening techniques, cloning, culture media, among several details which enable and optimizes its use. Nowadays, monoclonal antibodies are a well-established tool for proteomics research and it have countless applications on several knowledge areas, mainly human and/or animal disease diagnostic, identification and tracking of allergenic compounds in food and residues in the environment. This review can be used by professionals, researches and students searching for a compiled papers contributing to the improvement of the monoclonal antibodies technology, used at different knowledge areas such as human diseases and diseases and disorders in agriculture and livestock chain.

  7. Antibody affinity maturation

    DEFF Research Database (Denmark)

    Skjødt, Mette Louise

    fragments by in vivo homologous recombination large combinatorial antibody libraries can easily be generated. We have optimized ordered assembly of three CDR fragments into a gapped vector and observed increased transformation efficiency in a yeast strain carrying a deletion of the SGS1 helicase...... surface expression of various antibody formats in the generated knockout strain. Functional scFv and scFab fragments were efficiently displayed on yeast whereas impaired chain assembly and heavy chain degradation was observed for display of full-length IgG molecules. To identify the optimal polypeptide...... linker for yeast surface display of scFv and scFab fragments, we compared a series of different Gly-Ser-based linkers in display and antigen binding proficiency. We show that these formats of the model antibody can accommodate linkers of different lengths and that introduction of alanine or glutamate...

  8. Antibody informatics for drug discovery

    DEFF Research Database (Denmark)

    Shirai, Hiroki; Prades, Catherine; Vita, Randi

    2014-01-01

    to the antibody science in every project in antibody drug discovery. Recent experimental technologies allow for the rapid generation of large-scale data on antibody sequences, affinity, potency, structures, and biological functions; this should accelerate drug discovery research. Therefore, a robust bioinformatic...... infrastructure for these large data sets has become necessary. In this article, we first identify and discuss the typical obstacles faced during the antibody drug discovery process. We then summarize the current status of three sub-fields of antibody informatics as follows: (i) recent progress in technologies...... for antibody rational design using computational approaches to affinity and stability improvement, as well as ab-initio and homology-based antibody modeling; (ii) resources for antibody sequences, structures, and immune epitopes and open drug discovery resources for development of antibody drugs; and (iii...

  9. Prediction of Antibody Epitopes

    DEFF Research Database (Denmark)

    Nielsen, Morten; Marcatili, Paolo

    2015-01-01

    Antibodies recognize their cognate antigens in a precise and effective way. In order to do so, they target regions of the antigenic molecules that have specific features such as large exposed areas, presence of charged or polar atoms, specific secondary structure elements, and lack of similarity...... to self-proteins. Given the sequence or the structure of a protein of interest, several methods exploit such features to predict the residues that are more likely to be recognized by an immunoglobulin.Here, we present two methods (BepiPred and DiscoTope) to predict linear and discontinuous antibody...

  10. Anti-B cell antibody therapies for inflammatory rheumatic diseases

    DEFF Research Database (Denmark)

    Faurschou, Mikkel; Jayne, David R W

    2014-01-01

    Several monoclonal antibodies targeting B cells have been tested as therapeutics for inflammatory rheumatic diseases. We review important observations from randomized clinical trials regarding the efficacy and safety of anti-B cell antibody-based therapies for rheumatoid arthritis, systemic lupus...... erythematosus, antineutrophil cytoplasmic antibody-associated vasculitis, polymyositis/dermatomyositis, and primary Sjögren's syndrome. For some anti-B cell agents, clinical benefits have been convincingly demonstrated, while other B cell-targeted therapies failed to improve outcomes when added to standard...... and functions in rheumatic disorders. Future studies should also evaluate how to maintain disease control by means of conventional and/or biologic immunosuppressants after remission-induction with anti-B cell antibodies....

  11. Monoclonal Antibodies for Relapsing Multiple Sclerosis

    DEFF Research Database (Denmark)

    Blinkenberg, Morten; Soelberg Sørensen, Per

    2017-01-01

    leading to chronic central nervous system (CNS) demyelination, neural loss, and, finally, neurological disability. Although a number of disease-modifying treatments are available for the treatment of the inflammatory phase of MS, there is still a need for highly efficacious therapies with an acceptable...... safety profile in order to gain therapeutic control early in the disease course. Monoclonal antibodies have proven to be some of the most efficacious disease-modifying therapies in the field of MS, and recent developments in clinical research hold promise for new compounds fulfilling the need...

  12. Impact of antibody subclass and disulfide isoform differences on the biological activity of CD200R and βklotho agonist antibodies.

    Science.gov (United States)

    Grujic, Ognjen; Stevens, Jennitte; Chou, Robert Y-T; Weiszmann, Jennifer V; Sekirov, Laura; Thomson, Christy; Badh, Anita; Grauer, Stephanie; Chan, Brian; Graham, Kevin; Manchulenko, Kathy; Dillon, Thomas M; Li, Yang; Foltz, Ian N

    2017-05-13

    Agonism of cell surface receptors by monoclonal antibodies is dependent not only on its ability to bind the target, but also to deliver a biological signal through receptors to the cell. Immunoglobulin G2 antibodies (IgG2s) are made up of a mixture of distinct isoforms (IgG2-A, -B and A/B), which differ by the disulfide connectivity at the hinge region. When evaluating panels of agonistic antibodies against CD200 receptor (CD200R) or βklotho receptor (βklotho), we noticed striking activity differences of IgG1 or IgG2 antibodies with the same variable domains. For the CD200R antibody, the IgG2 antibody demonstrated higher activity than the IgG1 or IgG4 antibody. More significantly, for βklotho, agonist antibodies with higher biological activity as either IgG2 or IgG1 were identified. In both cases, ion exchange chromatography was able to isolate the bioactivity to the IgG2-B isoform from the IgG2 parental mixture. The subclass-related increase in agonist activity was not correlated with antibody aggregation or binding affinity, but was driven by enhanced avidity for the CD200R antibody. These results add to the growing body of evidence that show that conformational differences in the antibody hinge region can have a dramatic impact on the antibody activity and must be considered when screening and engineering therapeutic antibody candidates. The results also demonstrate that the IgG1 (IgG2-A like) or the IgG2-B form may provide the most active form of agonist antibodies for different antibodies and targets. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Anti-DNA antibody mediated catalysis is isotype dependent.

    Science.gov (United States)

    Xia, Yumin; Eryilmaz, Ertan; Zhang, Qiuting; Cowburn, David; Putterman, Chaim

    2016-01-01

    Anti-DNA antibodies are the serological hallmark of systemic lupus erythematosus, and participate in the pathogenesis of lupus nephritis by cross-reacting with multiple renal antigens. Previously, using a panel of murine anti-DNA IgGs that share identical variable regions but that differ in the constant regions, we demonstrated that the cross-reaction and renal pathogenicity of anti-DNA antibodies are isotype dependent. In this study, we investigated the catalytic potential of this anti-DNA antibody panel, and determined its isotype dependency. The three isotype switch variants (IgG1, IgG2a, IgG2b) and the parent IgG3 PL9-11 anti-DNA antibodies were compared in their catalysis of 500 base pair linear double stranded DNA and a 12-mer peptide (ALWPPNLHAWVP), by gel analysis, MALDI-TOF mass spectrometry, and nuclear magnetic resonance spectroscopy. The binding affinity of anti-DNA antibodies to double stranded DNA and peptide antigens were assessed by ELISA and surface plasmon resonance. We found that the PL9-11 antibody isotypes vary significantly in their potential to catalyze the cleavage of both linear and double stranded DNA and the proteolysis of peptides. The degree of the cleavage and proteolysis increases with the incubation temperature and time. While different PL9-11 isotypes have the same initial attack sites within the ALWPPNLHAWVP peptide, there was no correlation between binding affinity to the peptide and proteolysis rates. In conclusion, the catalytic properties of anti-DNA antibodies are isotype dependent. This finding provides further evidence that antibodies that share the same variable region, but which have different constant regions, are functionally distinct. The catalytic effects modulated by antibody constant regions need to be considered in the design of therapeutic antibodies (abzymes) and peptides designed to block pathogenic autoantibodies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Gene-Based Antibody Strategies for Prion Diseases

    Directory of Open Access Journals (Sweden)

    Alessio Cardinale

    2013-01-01

    Full Text Available Prion diseases or transmissible spongiform encephalopathies (TSE are a group of neurodegenerative and infectious disorders characterized by the conversion of a normal cellular protein PrPC into a pathological abnormally folded form, termed PrPSc. There are neither available therapies nor diagnostic tools for an early identification of individuals affected by these diseases. New gene-based antibody strategies are emerging as valuable therapeutic tools. Among these, intrabodies are chimeric molecules composed by recombinant antibody fragments fused to intracellular trafficking sequences, aimed at inhibiting, in vivo, the function of specific therapeutic targets. The advantage of intrabodies is that they can be selected against a precise epitope of target proteins, including protein-protein interaction sites and cytotoxic conformers (i.e., oligomeric and fibrillar assemblies. Herein, we address and discuss in vitro and in vivo applications of intrabodies in prion diseases, focussing on their therapeutic potential.

  15. Expression of recombinant vaccines and antibodies in plants.

    Science.gov (United States)

    Ko, Kisung

    2014-06-01

    Plants are able to perform post-translational maturations of therapeutic proteins required for their functional biological activity and suitable in vivo pharmacokinetics. Plants can be a low-cost, large-scale production platform of recombinant biopharmaceutical proteins such as vaccines and antibodies. Plants, however, lack mechanisms of processing authentic human N-glycosylation, which imposes a major limitation in their use as an expression system for therapeutic glycoproducts. Efforts have been made to circumvent plant-specific N-glycosylation, as well as to supplement the plant's endogenous system with human glycosyltransferases for non-immunogenic and humanized N-glycan production. Herein we review studies on the potential of plants to serve as production systems for therapeutic and prophylactic biopharmaceuticals. We have especially focused on recombinant vaccines and antibodies and new expression strategies to overcome the existing problems associated with their production in plants.

  16. Compositions, antibodies, asthma diagnosis methods, and methods for preparing antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hongjun; Zangar, Richard C.

    2017-01-17

    Methods for preparing an antibody are provided with the method including incorporating 3-bromo-4-hydroxy-benzoic acid into a protein to form an antigen, immunizing a mammalian host with the antigen, and recovering an antibody having an affinity for the antigen from the host. Antibodies having a binding affinity for a monohalotyrosine are provided as well as composition comprising an antibody bound with monohalotyrosine. Compositions comprising a protein having a 3-bromo-4-hydroxy-benzoic acid moiety are also provided. Methods for evaluating the severity of asthma are provide with the methods including analyzing sputum of a patient using an antibody having a binding affinity for monohalotyrosine, and measuring the amount of antibody bound to protein. Methods for determining eosinophil activity in bodily fluid are also provided with the methods including exposing bodily fluid to an antibody having a binding affinity for monohalotyrosine, and measuring the amount of bound antibody to determine the eosinophil activity.

  17. Bispecific Antibodies as a Development Platform for New Concepts and Treatment Strategies

    Directory of Open Access Journals (Sweden)

    Fa Yang

    2016-12-01

    Full Text Available With the development of molecular cloning technology and the deep understanding of antibody engineering, there are diverse bispecific antibody formats from which to choose to pursue the optimal biological activity and clinical purpose. The single-chain-based bispecific antibodies usually bridge tumor cells with immune cells and form an immunological synapse because of their relatively small size. Bispecific antibodies in the IgG format include asymmetric bispecific antibodies and homodimerized bispecific antibodies, all of which have an extended blood half-life and their own crystalline fragment (Fc-mediated functions. Besides retargeting effector cells to the site of cancer, new applications were established for bispecific antibodies. Bispecific antibodies that can simultaneously bind to cell surface antigens and payloads are a very ideal delivery system for therapeutic use. Bispecific antibodies that can inhibit two correlated signaling molecules at the same time can be developed to overcome inherent or acquired resistance and to be more efficient angiogenesis inhibitors. Bispecific antibodies can also be used to treat hemophilia A by mimicking the function of factor VIII. Bispecific antibodies also have broad application prospects in bone disorders and infections and diseases of the central nervous system. The latest developments of the formats and application of bispecific antibodies will be reviewed. Furthermore, the challenges and perspectives are summarized in this review.

  18. Therapeutic use exemption

    Science.gov (United States)

    Dvorak, J; Kirkendall, D; Vouillamoz, M

    2006-01-01

    Football players who have either physical symptoms or disease after injury may need to be treated with specific medicines that are on the list of prohibited substances. Therapeutic use exemption may be granted to such players, in accordance with strictly defined criteria—these are presented in this article. Procedures of how to request for an abbreviated or a standard therapeutic use exemption are explained, and data on therapeutic use exemptions (UEFA and FIFA, 2004 and 2005) are also presented. PMID:16799102

  19. Fetal neonatal hyperthyroidism: diagnostic and therapeutic approachment

    Science.gov (United States)

    Kurtoğlu, Selim; Özdemir, Ahmet

    2017-01-01

    Fetal and neonatal hyperthyroidism may occur in mothers with Graves’ disease. Fetal thyrotoxicosis manifestation is observed with the transition of TSH receptor stimulating antibodies to the fetus from the 17th–20th weeks of pregnancy and with the fetal TSH receptors becoming responsive after 20 weeks. The diagnosis is confirmed by fetal tachycardia, goiter and bone age advancement in pregnancy and maternal treatment is conducted in accordance. The probability of neonatal hyperthyroidism is high in the babies of mothers that have ongoing antithyroid requirement and higher antibody levels in the last months of pregnancy. Clinical manifestation may be delayed by 7–17 days because of the antithyroid drugs taken by the mother. Neonatal hyperthyroidism symptoms can be confused with sepsis and congenital viral infections. Herein, the diagnosis and therapeutic approach are reviewed in cases of fetal neonatal hyperthyroidism. PMID:28439194

  20. Recent Patents on Heat Shock Proteins Targeting Antibodies.

    Science.gov (United States)

    Fernandes, Joao C; Alves, Pedro

    2017-01-01

    Heat shock proteins (Hsp) are major chaperone molecules that have recently emerged as cancer therapeutic targets owing to their involvement in tumor cell proliferation, differentiation, invasion and metastasis. High levels of extracellular Hsp90 and Hsp70 have been closely associated with a wide range of human cancers. Accumulating evidence suggests that the pharmacological inhibition of these molecules can play a pivotal role in non-surgical cancer treatment. Efforts have been taken to develop monoclonal antibodies (mAbs) and antibody fragments targeting extracellular Hsp90 and Hsp70, alone or conjugated with standard anticancer agents, to control several types of cancer, such as breast, colon, prostate or melanoma. To provide an overview on the development of monoclonal antibodies and antibody fragments with capacity to bind Hsp90 and Hsp70, aiming at being used for cancer treatment. A systematic review was performed using European Patent Office and Google patents databases. Based on the available literature and patents, we report the potential anticancer strategies based on these biological molecules. Supported by the recent developments in this field, Hsp targeting antibodies therapy may emerge for clinical use in the future for cancer patients, namely as antibody-drug conjugates combining the specificity of these antibodies with the potency of cytotoxic drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. Human germline antibody gene segments encode polyspecific antibodies.

    Science.gov (United States)

    Willis, Jordan R; Briney, Bryan S; DeLuca, Samuel L; Crowe, James E; Meiler, Jens

    2013-04-01

    Structural flexibility in germline gene-encoded antibodies allows promiscuous binding to diverse antigens. The binding affinity and specificity for a particular epitope typically increase as antibody genes acquire somatic mutations in antigen-stimulated B cells. In this work, we investigated whether germline gene-encoded antibodies are optimal for polyspecificity by determining the basis for recognition of diverse antigens by antibodies encoded by three VH gene segments. Panels of somatically mutated antibodies encoded by a common VH gene, but each binding to a different antigen, were computationally redesigned to predict antibodies that could engage multiple antigens at once. The Rosetta multi-state design process predicted antibody sequences for the entire heavy chain variable region, including framework, CDR1, and CDR2 mutations. The predicted sequences matched the germline gene sequences to a remarkable degree, revealing by computational design the residues that are predicted to enable polyspecificity, i.e., binding of many unrelated antigens with a common sequence. The process thereby reverses antibody maturation in silico. In contrast, when designing antibodies to bind a single antigen, a sequence similar to that of the mature antibody sequence was returned, mimicking natural antibody maturation in silico. We demonstrated that the Rosetta computational design algorithm captures important aspects of antibody/antigen recognition. While the hypervariable region CDR3 often mediates much of the specificity of mature antibodies, we identified key positions in the VH gene encoding CDR1, CDR2, and the immunoglobulin framework that are critical contributors for polyspecificity in germline antibodies. Computational design of antibodies capable of binding multiple antigens may allow the rational design of antibodies that retain polyspecificity for diverse epitope binding.

  2. Prediction of antibody persistency from antibody titres to natalizumab

    DEFF Research Database (Denmark)

    Jensen, Poul Erik H; Koch-Henriksen, Nils; Sellebjerg, Finn Thorup

    2012-01-01

    In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients.......In a subgroup of patients with multiple sclerosis natalizumab therapy causes generation of anti-natalizumab antibodies that may be transient or persistent. It is recommended to discontinue natalizumab therapy in persistently antibody-positive patients....

  3. Monoclonal antibodies in haematopathology

    Energy Technology Data Exchange (ETDEWEB)

    Grignani, F.; Martelli, M.F.; Mason, D.Y.

    1985-01-01

    This book contains over 40 selections. Some of the titles are: Oncogene (c-myc, c-myb) amplification in acute myelogenous leukaemia; Ultrastructural characterization of leukaemic cells with monoloclonal antibodies; Origin of B-cell malignancies; Immunohistology of gut lymphomas; and Spurious evidence of lineage infidelity in monocytic leukaemia.

  4. Monoclonal antibodies in myeloma

    DEFF Research Database (Denmark)

    Sondergeld, P.; van de Donk, N. W. C. J.; Richardson, P. G.

    2015-01-01

    The development of monoclonal antibodies (mAbs) for the treatment of disease goes back to the vision of Paul Ehrlich in the late 19th century; however, the first successful treatment with a mAb was not until 1982, in a lymphoma patient. In multiple myeloma, mAbs are a very recent and exciting add...

  5. Antibodies Targeting EMT

    Science.gov (United States)

    2015-10-01

    biomarkers. We have developed a new technique allowing for discovery of new antibodies that disrupt a key process in cancer progression termed...14 post Twist induction to trigger EMT. 7 within CDRH3s, the RGD motif could be indicative of ligand mimetic integrin binding properties of these

  6. The effect of immunoscintigraphy with monoclonal antibodies on assays of hormones and tumor markers. This is not the end of the matter!

    NARCIS (Netherlands)

    J.A.M.J.L. Janssen (Joseph); P.J. Blankestijn (Peter); R. Docter (Roel); B.G. Blijenberg (Bert); S.W.J. Lamberts (Steven); E.P. Krenning (Eric)

    1989-01-01

    textabstractThe use of monoclonal antibodies in medicine for in-vivo diagnostic methods and for therapeutic purposes will increase in the future. Although monoclonal antibodies possess a high specificity, the animal origin of these antibodies remains a problem. Repeated

  7. Generation of anti-idiotype scFv for pharmacokinetic measurement in lymphoma patients treated with chimera anti-CD22 antibody SM03.

    Directory of Open Access Journals (Sweden)

    Qi Zhao

    Full Text Available Pre-clinical and clinical studies of therapeutic antibodies require highly specific reagents to examine their immune responses, bio-distributions, immunogenicity, and pharmacodynamics in patients. Selective antigen-mimicking anti-idiotype antibody facilitates the assessment of therapeutic antibody in the detection, quantitation and characterization of antibody immune responses. Using mouse specific degenerate primer pairs and splenocytic RNA, we generated an idiotype antibody-immunized phage-displayed scFv library in which an anti-idiotype antibody against the therapeutic chimera anti-CD22 antibody SM03 was isolated. The anti-idiotype scFv recognized the idiotype of anti-CD22 antibody and inhibited binding of SM03 to CD22 on Raji cell surface. The anti-idiotype scFv was subsequently classified as Ab2γ type. Moreover, our results also demonstrated firstly that the anti-idiotype scFv could be used for pharmacokinetic measurement of circulating residual antibody in lymphoma patients treated with chimera anti-CD22 monoclonal antibody SM03. Of important, the present approach could be easily adopted to generate anti-idiotype antibodies for therapeutic antibodies targeting membrane proteins, saving the cost and time for producing a soluble antigen.

  8. Improved in vivo anti-tumor effects of IgA-Her2 antibodies through half-life extension and serum exposure enhancement by FcRn targeting

    NARCIS (Netherlands)

    Meyer, Saskia; Nederend, Maaike; Jansen, J H Marco; Reiding, Karli R; Jacobino, Shamir R; Meeldijk, Jan; Bovenschen, Niels; Wuhrer, Manfred; Valerius, Thomas; Ubink, Ruud; Boross, Peter; Rouwendal, Gerard; Leusen, Jeanette H W

    2016-01-01

    Antibody therapy is a validated treatment approach for several malignancies. All currently clinically applied therapeutic antibodies (Abs) are of the IgG isotype. However, not all patients respond to this therapy and relapses can occur. IgA represents an alternative isotype for antibody therapy that

  9. A novel antibody discovery platform identifies anti-influenza A broadly neutralizing antibodies from human memory B cells.

    Science.gov (United States)

    Xiao, Xiaodong; Chen, Yan; Varkey, Reena; Kallewaard, Nicole; Koksal, Adem C; Zhu, Qing; Wu, Herren; Chowdhury, Partha S; Dall'Acqua, William F

    2016-07-01

    Monoclonal antibody isolation directly from circulating human B cells is a powerful tool to delineate humoral responses to pathological conditions and discover antibody therapeutics. We have developed a platform aimed at improving the efficiencies of B cell selection and V gene recovery. Here, memory B cells are activated and amplified using Epstein-Barr virus infection, co-cultured with CHO-muCD40L cells, and then assessed by functional screenings. An in vitro transcription and translation (IVTT) approach was used to analyze variable (V) genes recovered from each B cell sample and identify the relevant heavy/light chain pair(s). We achieved efficient amplification and activation of memory B cells, and eliminated the need to: 1) seed B cells at clonal level (≤1 cell/well) or perform limited dilution cloning; 2) immortalize B cells; or 3) assemble V genes into an IgG expression vector to confirm the relevant heavy/light chain pairing. Cross-reactive antibodies targeting a conserved epitope on influenza A hemagglutinin were successfully isolated from a healthy donor. In-depth analysis of the isolated antibodies suggested their potential uses as anti-influenza A antibody therapeutics and uncovered a distinct affinity maturation pathway. Importantly, our results showed that cognate heavy/light chain pairings contributed to both the expression level and binding abilities of our newly isolated VH1-69 family, influenza A neutralizing antibodies, contrasting with previous observations that light chains do not significantly contribute to the function of this group of antibodies. Our results further suggest the potential use of the IVTT as a powerful antibody developability assessment tool.

  10. Exploring an orbitrap analyzer for the characterization of intact antibodies by native mass spectrometry

    NARCIS (Netherlands)

    Rose, R.J.; Thompson, N.J.; Van Duijn, E.; Damoc, E.; Denisov, E.; Makarov, A.; Heck, A.J.R

    2012-01-01

    Monoclonal antibodies (mAbs) represent a major class of therapeutic biomolecules being developed by the biopharmaceutical industry, their popularity largely being a result of their high specificity towards targets. Therapeutic mAbs are being developed for various diseases, with a strong focus on

  11. SINGLE CHAIN VARIABLE FRAGMENTS OF ANTIBODIES AGAINST DIPHTHERIA TOXIN B-SUBUNIT ISOLATED FROM PHAGE DISPLAY HUMAN ANTIBODY LIBRARY

    Directory of Open Access Journals (Sweden)

    Oliinyk O. S.

    2014-02-01

    Full Text Available Diphtheria toxin is an exoantigen of Corynebacterium diphtheriae that inhibits protein synthesis and kills sensitive cells. The aim of this study was to obtain human recombinant single-chain variable fragment (scFv antibodies against receptor-binding B subunit of diphtheria toxin. 12 specific clones were selected after three rounds of a phage display naїve (unimmunized human antibody library against recombinant B-subunit. scFv DNA inserts from these 12 clones were digested with MvaI, and 6 unique restriction patterns were found. Single-chain antibodies were expressed in Escherichia coli XL1-blue. The recombinant proteins were characterized by immunoblotting of bacterial extracts and detection with an anti-E-tag antibody. The toxin B-subunit-binding function of the single-chain antibody was shown by ELISA. The affinity constants for different clones were found to be from 106 to 108 М–1. Due to the fact, that these antibody fragments recognized epitopes in the receptor-binding Bsubunit of diphtheria toxin, further studies are interesting to evaluate their toxin neutralization properties and potential for therapeutic applications. Obtained scFv-antibodies can also be used for detection and investigation of biological properties of diphtheria toxin.

  12. Structural Characterization of Peptide Antibodies

    DEFF Research Database (Denmark)

    Chailyan, Anna; Marcatili, Paolo

    2015-01-01

    can be modified to obtain desired properties or conformation, tagged for purification, isotopically labeled for protein quantitation or conjugated to immunogens for antibody production. The antibodies that bind to these peptides represent an invaluable tool for biological research and discovery...

  13. Sputum direct fluorescent antibody (DFA)

    Science.gov (United States)

    ... ency/article/003553.htm Sputum direct fluorescent antibody (DFA) test To use the sharing features on this page, please enable JavaScript. Sputum direct fluorescent antibody (DFA) is a lab test that looks for micro- ...

  14. Antineurofilament antibodies in postpolio syndrome.

    Science.gov (United States)

    Drory, V E; Shapira, A; Korczyn, A D; Shavit, S; Kushnir, M; Michaelson, D M; Chapman, J

    1998-10-01

    We determined the levels of antineurofilament antibodies in 29 patients with postpolio syndrome (PPS), 26 stable postpolio (PP) patients, 22 patients with ALS, and 20 normal controls (NCs). Patients with PPS had higher antibody levels to cholinergic neurofilaments than did all other groups. PP patients and those with ALS had antibody levels similar to those of NCs. The antibody binding level showed no relation to the age of the patients, duration of disease, or motor score.

  15. Neutralizing human antibodies prevent Zika virus replication and fetal disease in mice.

    Science.gov (United States)

    Sapparapu, Gopal; Fernandez, Estefania; Kose, Nurgun; Bin Cao; Fox, Julie M; Bombardi, Robin G; Zhao, Haiyan; Nelson, Christopher A; Bryan, Aubrey L; Barnes, Trevor; Davidson, Edgar; Mysorekar, Indira U; Fremont, Daved H; Doranz, Benjamin J; Diamond, Michael S; Crowe, James E

    2016-12-15

    Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that can cause severe disease, including congenital birth defects during pregnancy. To develop candidate therapeutic agents against ZIKV, we isolated a panel of human monoclonal antibodies from subjects that were previously infected with ZIKV. We show that a subset of antibodies recognize diverse epitopes on the envelope (E) protein and exhibit potent neutralizing activity. One of the most inhibitory antibodies, ZIKV-117, broadly neutralized infection of ZIKV strains corresponding to African and Asian-American lineages. Epitope mapping studies revealed that ZIKV-117 recognized a unique quaternary epitope on the E protein dimer-dimer interface. We evaluated the therapeutic efficacy of ZIKV-117 in pregnant and non-pregnant mice. Monoclonal antibody treatment markedly reduced tissue pathology, placental and fetal infection, and mortality in mice. Thus, neutralizing human antibodies can protect against maternal-fetal transmission, infection and disease, and reveal important determinants for structure-based rational vaccine design efforts.

  16. Antibody targeting of Cathepsin S induces antibody-dependent cellular cytotoxicity

    Directory of Open Access Journals (Sweden)

    Kwok Hang Fai

    2011-12-01

    Full Text Available Abstract Background Proteolytic enzymes have been implicated in driving tumor progression by means of their cancer cell microenvironment activity where they promote proliferation, differentiation, apoptosis, migration, and invasion. Therapeutic strategies have focused on attenuating their activity using small molecule inhibitors, but the association of proteases with the cell surface during cancer progression opens up the possibility of targeting these using antibody dependent cellular cytotoxicity (ADCC. Cathepsin S is a lysosomal cysteine protease that promotes the growth and invasion of tumour and endothelial cells during cancer progression. Our analysis of colorectal cancer patient biopsies shows that cathepsin S associates with the cell membrane indicating a potential for ADCC targeting. Results Here we report the cell surface characterization of cathepsin S and the development of a humanized antibody (Fsn0503h with immune effector function and a stable in vivo half-life of 274 hours. Cathepsin S is expressed on the surface of tumor cells representative of colorectal and pancreatic cancer (23%-79% positive expression. Furthermore the binding of Fsn0503h to surface associated cathepsin S results in natural killer (NK cell targeted tumor killing. In a colorectal cancer model Fsn0503h elicits a 22% cytotoxic effect. Conclusions This data highlights the potential to target cell surface associated enzymes, such as cathepsin S, as therapeutic targets using antibodies capable of elicitingADCC in tumor cells.

  17. Development of Human Monoclonal Antibodies Against Respiratory Syncytial Virus Using a High Efficiency Human Hybridoma Technique.

    Science.gov (United States)

    Alvarado, Gabriela; Crowe, James E

    2016-01-01

    Human monoclonal antibodies against RSV have high potential for use as prophylaxis or therapeutic molecules, and they also can be used to define the structure of protective epitopes for rational vaccine design. In the past, however, isolation of human monoclonal antibodies was difficult and inefficient. Here, we describe contemporary methods for activation and proliferation of primary human memory B cells followed by cytofusion to non-secreting myeloma cells by dielectrophoresis to generate human hybridomas secreting RSV-specific monoclonal antibodies. We also provide experimental methods for screening human B cell lines to obtain RSV-specific lines, especially lines secreting neutralizing antibodies.

  18. 6th Annual European Antibody Congress 2010: November 29-December 1, 2010, Geneva, Switzerland.

    Science.gov (United States)

    Beck, Alain; Wurch, Thierry; Reichert, Janice M

    2011-01-01

    The 6th European Antibody Congress (EAC), organized by Terrapinn Ltd., was held in Geneva, Switzerland, which was also the location of the 4th and 5th EAC. As was the case in 2008 and 2009, the EAC was again the largest antibody congress held in Europe, drawing nearly 250 delegates in 2010. Numerous pharmaceutical and biopharmaceutical companies active in the field of therapeutic antibody development were represented, as were start-up and academic organizations and representatives from the US Food and Drug Administration FDA. The global trends in antibody research and development were discussed, including success stories of recent marketing authorizations of golimumab (Simponi®) and canakinumab (Ilaris®) by Johnson & Johnson and Novartis, respectively, updates on antibodies in late clinical development (obinutuzumab/GA101, farletuzumab/MORAb-003 and itolizumab/T1 h, by Glycart/Roche, Morphotek and Biocon, respectively) and success rates for this fast-expanding class of therapeutics (Tufts Center for the Study of Drug Development). Case studies covering clinical progress of girentuximab (Wilex), evaluation of panobacumab (Kenta Biotech), characterization of therapeutic antibody candidates by protein microarrays (Protagen), antibody-drug conjugates (sanofi-aventis, ImmunoGen, Seattle Genetics, Wyeth/Pfizer), radio-immunoconjugates (Bayer Schering Pharma, Université de Nantes) and new scaffolds (Ablynx, AdAlta, Domantis/GlaxoSmithKline, Fresenius, Molecular Partners, Pieris, Scil Proteins, Pfizer, University of Zurich) were presented. Major antibody structural improvements were showcased, including the latest selection engineering of the best isotypes (Abbott, Pfizer, Pierre Fabre), hinge domain (Pierre Fabre), dual antibodies (Abbott), IgG-like bispecific antibodies (Biogen Idec), antibody epitope mapping case studies (Eli Lilly), insights in FcγRII receptor (University of Cambridge), as well as novel tools for antibody fragmentation (Genovis). Improvements of

  19. Chicanoizing the Therapeutic Community

    Science.gov (United States)

    Aron, William S.; And Others

    1974-01-01

    Focusing on the drug addiction problem and its antecedent conditions in a Chicano population, the article examines several therapeutic interventions suggested by these conditions and indicates how they might be incorporated into a drug addiction Therapeutic Community treatment program designed to meet the needs of Chicano drug addicts. (Author/NQ)

  20. Therapeutic Crisis Intervention.

    Science.gov (United States)

    Holden, Martha J.; Powers, Jane Levine

    1993-01-01

    Describes Therapeutic Crisis Intervention (TCI) program as providing staff with skills, knowledge, and confidence to manage child in crisis to bring about a "maximum amount of lasting response." Contends that, by applying principles of TCI training, direct care worker can attain therapeutic control and maintain dignity of both adult and child…

  1. Trends in Therapeutic Recreation.

    Science.gov (United States)

    Smith, Ralph W.

    1995-01-01

    Discusses the implications of the rapid, dramatic changes taking place in therapeutic recreation for individuals with physical disabilities. The article notes the impact of changes in managed care, examines programming trends in therapeutic recreation (adventure/outdoor education, competitive sports, handcycling, health enhancement activities, and…

  2. Reporting therapeutic discourse in a therapeutic community.

    Science.gov (United States)

    Chapman, G E

    1988-03-01

    Research in nurses' communications has concentrated on nurse to patient interactions. Those few studies which focus on nurse to nurse communications seem to be generated by a pragmatic and normative concern with effective information sharing. In this paper, which describes one aspect of a larger case study of a hospital-based therapeutic community, the description and analysis of nurses' reports flows not from a normative model of professional practice, but rather an exploration of how professional practice is articulated as discourse in nurses' written accounts. Foucault's ideas about therapeutic discourse inform the theoretical framework of the research. Ethnomethodological concerns with the importance of documentary analysis provide the methodological rationale for examining nurses' 24-hour report documents, as official discourse, reflecting therapeutic practice in this setting. A content analysis of nurses' reports, collected over a period of 4 months, demonstrated the importance of domesticity and ordinary everyday activities in nurses' accounts of hospital life. Disruption to the 'life as usual' domesticity in the community seemed to be associated with admission to and discharge from the hospital when interpersonal and interactional changes between patients occur. It is suggested that nurses in general hospital wards and more orthodox psychiatric settings might usefully consider the impact of admissions and discharges on the group of patients they manage, and make this a discursive focus of their work.

  3. Antibody Selection for Cancer Target Validation of FSH-Receptor in Immunohistochemical Settings

    Directory of Open Access Journals (Sweden)

    Nina Moeker

    2017-10-01

    Full Text Available Background: The follicle-stimulating hormone (FSH-receptor (FSHR has been reported to be an attractive target for antibody therapy in human cancer. However, divergent immunohistochemical (IHC findings have been reported for FSHR expression in tumor tissues, which could be due to the specificity of the antibodies used. Methods: Three frequently used antibodies (sc-7798, sc-13935, and FSHR323 were validated for their suitability in an immunohistochemical study for FSHR expression in different tissues. As quality control, two potential therapeutic anti-hFSHR Ylanthia® antibodies (Y010913, Y010916 were used. The specificity criteria for selection of antibodies were binding to native hFSHR of different sources, and no binding to non-related proteins. The ability of antibodies to stain the paraffin-embedded Flp-In Chinese hamster ovary (CHO/FSHR cells was tested after application of different epitope retrieval methods. Results: From the five tested anti-hFSHR antibodies, only Y010913, Y010916, and FSHR323 showed specific binding to native, cell-presented hFSHR. Since Ylanthia® antibodies were selected to specifically recognize native FSHR, as required for a potential therapeutic antibody candidate, FSHR323 was the only antibody to detect the receptor in IHC/histochemical settings on transfected cells, and at markedly lower, physiological concentrations (ex., in Sertoli cells of human testes. The pattern of FSH323 staining noticed for ovarian, prostatic, and renal adenocarcinomas indicated that FSHR was expressed mainly in the peripheral tumor blood vessels. Conclusion: Of all published IHC antibodies tested, only antibody FSHR323 proved suitable for target validation of hFSHR in an IHC setting for cancer. Our studies could not confirm the previously reported FSHR overexpression in ovarian and prostate cancer cells. Instead, specific overexpression in peripheral tumor blood vessels could be confirmed after thorough validation of the antibodies used.

  4. Characterization of Tumor-Avid Antibody Fragments Genetically Engineered for Mono-Specific Radionuclide Chelation

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, T.P.

    2003-12-31

    The successful clinical application of targeted-radiopharmaceuticals depends on the development of molecules that optimize tumor specific radionuclide deposition and minimize non-specific organ irradiation. To this end, this proposal outlines a research effort to identify and evaluate novel antibodies and antibody fragments that bind breast tumors. The tumor-avid antibodies will be investigated for as imaging and therapeutic agents and to gain a better understanding of the pharmacokinetics and metabolism of radiolabeled tumor-avid antibody fragments through the use of site-specifically labeled molecules. Antibodies or antibody fragments, that bind breast carcinoma carbohydrate antigens, will be obtained from hybridoma or bacteriophage library screening. More specifically, antibody fragments that bind the carcinoma-associated Thomsen-Friedenreich (T) antigen will be radiolabeled with {sup 99m}Tc and {sup 188}Re at a natural amino acid chelation site and will be investigated in vivo for their abilities to target human breast tumors. In addition, site-specific radiolabeled antibody fragments will be biosynthesized using misacylated suppressor tRNAs. Homogeneously radiolabeled populations of antibody fragments will be used to investigate the effects of radionuclide location and chelation chemistries on their biodistribution and metabolism. It is hypothesized that site-specifically radiolabeled antibody fragments will possess enhanced tumor imaging and therapeutic properties due to optimal label location and conjugation chemistries. New insights into the factors that govern antibody metabolism in vivo are also expected from this work. Results from these studies should enhance our ability to design and synthesize radiolabeled antibody fragments that have improved pharmacokinetic properties. The studies in this proposal involve basic research into the development of antibody-based radiopharmaceuticals, with the ultimate goal of application in humans. This type of basic

  5. Introduction to current and future protein therapeutics: a protein engineering perspective.

    Science.gov (United States)

    Carter, Paul J

    2011-05-15

    Protein therapeutics and its enabling sister discipline, protein engineering, have emerged since the early 1980s. The first protein therapeutics were recombinant versions of natural proteins. Proteins purposefully modified to increase their clinical potential soon followed with enhancements derived from protein or glycoengineering, Fc fusion or conjugation to polyethylene glycol. Antibody-based drugs subsequently arose as the largest and fastest growing class of protein therapeutics. The rationale for developing better protein therapeutics with enhanced efficacy, greater safety, reduced immunogenicity or improved delivery comes from the convergence of clinical, scientific, technological and commercial drivers that have identified unmet needs and provided strategies to address them. Future protein drugs seem likely to be more extensively engineered to improve their performance, e.g., antibodies and Fc fusion proteins with enhanced effector functions or extended half-life. Two old concepts for improving antibodies, namely antibody-drug conjugates and bispecific antibodies, have advanced to the cusp of clinical success. As for newer protein therapeutic platform technologies, several engineered protein scaffolds are in early clinical development and offer differences and some potential advantages over antibodies. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Rapid characterization of binding specificity and cross-reactivity of antibodies using recombinant human protein arrays.

    Science.gov (United States)

    Kijanka, Gregor; Ipcho, Simon; Baars, Sabine; Chen, Hong; Hadley, Katie; Beveridge, Allan; Gould, Edith; Murphy, Derek

    2009-01-30

    Antibodies are routinely used as research tools, in diagnostic assays and increasingly as therapeutics. Ideally, these applications require antibodies with high sensitivity and specificity; however, many commercially available antibodies are limited in their use as they cross-react with non-related proteins. Here we describe a novel method to characterize antibody specificity. Six commercially available monoclonal and polyclonal antibodies were screened on high-density protein arrays comprising of ~10,000 recombinant human proteins (Imagenes). Two of the six antibodies examined; anti-pICln and anti-GAPDH, bound exclusively to their target antigen and showed no cross-reactivity with non-related proteins. However, four of the antibodies, anti-HSP90, anti-HSA, anti-bFGF and anti-Ro52, showed strong cross-reactivity with other proteins on the array. Antibody-antigen interactions were readily confirmed using Western immunoblotting. In addition, the redundant nature of the protein array used, enabled us to define the epitopic region within HSP90 of the anti-HSP90 antibody, and identify possible shared epitopes in cross-reacting proteins. In conclusion, high-density protein array technology is a fast and effective means for determining the specificity of antibodies and can be used to further improve the accuracy of antibody applications.

  7. Significance of persistence of antibodies against Leishmania infantum in Sicilian patients affected by acute visceral leishmaniasis.

    Science.gov (United States)

    Mansueto, Pasquale; Pepe, Ilenia; Seidita, Aurelio; Scozzari, Francesca; Vitale, Giustina; Arcoleo, Francesco; Elvira, Inglese; Cillari, Enrico; Rini, Giovam Battista; Napoli, Nicola; Di Rosa, Salvatore; Mansueto, Serafino; Di Fede, Gaetana

    2012-06-01

    The background of this article is as follows: Few data are available about the persistence of serum-specific IgG antibodies to L. infantum after acute VL. The objective of this article is to evaluate the persistence of antibodies against L. infantum in patients healed from acute VL, and the kinetic of the same antibodies observed in 2 cases of VL relapse and 2 cases of resistance to therapy. The methods which we used to obtain our objective are the following: 55 apparently immunocompetent, HIV-negative patients were examined for antibodies to L. infantum by IFAT over 14 years period, and we got the following results: Serum-specific IgG antibodies titers decrease slowly, but constantly. In the patients with a diagnosis of VL relapse, the kinetic of antibodies was characterized by an initial reduction, and a subsequent antibody levels rapidly increase, while in the patients with a clinical and parasitological diagnosis of VL not responding to specific therapy, we demonstrated persistent high level of antibodies to L. infantum. Finally, we conclude that specific antibodies to L. infantum might persist for many years, and decrease slowly, but steadily. The persistence of these specific antibodies is not related to poor therapeutic response or prognosis, but an acute increase in their levels might be a sentinel of a VL relapse, while persistence of high antibody levels could suggest a resistance to therapy.

  8. Highly efficient selection of epitope specific antibody through competitive yeast display library sorting.

    Science.gov (United States)

    Puri, Vinita; Streaker, Emily; Prabakaran, Ponraj; Zhu, Zhongyu; Dimitrov, Dimiter S

    2013-01-01

    Combinatory antibody library display technologies have been invented and successfully implemented for the selection and engineering of therapeutic antibodies. Precise targeting of important epitopes on the protein of interest is essential for such isolated antibodies to serve as effective modulators of molecular interactions. We developed a strategy to efficiently isolate antibodies against a specific epitope on a target protein from a yeast display antibody library using dengue virus envelope protein domain III as a model target. A domain III mutant protein with a key mutation inside a cross-reactive neutralizing epitope was designed, expressed, and used in the competitive panning of a yeast display naïve antibody library. All the yeast display antibodies that bound to the wild type domain III but not to the mutant were selectively sorted and characterized. Two unique clones were identified and showed cross-reactive binding to envelope protein domain IIIs from different serotypes. Epitope mapping of one of the antibodies confirmed that its epitope overlapped with the intended neutralizing epitope. This novel approach has implications for many areas of research where the isolation of epitope-specific antibodies is desired, such as selecting antibodies against conserved epitope(s) of viral envelope proteins from a library containing high titer, high affinity non-neutralizing antibodies, and targeting unique epitopes on cancer-related proteins.

  9. Treatment of refractory antibody mediated autoimmune disorders with an anti-CD20 monoclonal antibody (rituximab)

    Science.gov (United States)

    Arzoo, K; Sadeghi, S; Liebman, H

    2002-01-01

    Patients: Because of its novel mechanism of action, rituximab was used to treat three patients with refractory systemic antibody mediated autoimmune disorders. The first patient, a 71 year old woman with idiopathic type II mixed essential cryoglobulinaemia, had both dermatological and neurological manifestations with marked renal disease attributed to her cryoglobulinaemia. Patient 2, a 73 year old woman with Goodpasture's syndrome, was refractory to conventional treatment (cyclophosphamide, prednisone, plasmapheresis). She had persistent haemoptysis and haematuria and positive antiglomerular basement membrane antibodies. The third patient, a 75 year old man with primary biliary cirrhosis, myelodysplasia, and systemic immune complex vasculitis, had progressive renal insufficiency, a macular erythematous rash, and severe thrombocytopenia. Results: Treatment with rituximab resolved all clinical and laboratory manifestations in the three patients. Conclusions: Rituximab may be an important therapeutic agent for the treatment of patients refractory or intolerant to corticosteroid or cytotoxic treatment, or both. PMID:12228164

  10. The impact of mass spectrometry on the study of intact antibodies: from post-translational modifications to structural analysis

    NARCIS (Netherlands)

    Thompson, N.J.; Rosati, S; Rose, R.J.; Heck, A.J.R.

    2013-01-01

    Monoclonal antibodies (mAbs) are important therapeutics, targeting a variety of diseases ranging from cancers to neurodegenerative disorders. In developmental stages and prior to clinical use, these molecules require thorough structural characterisation, but their large size and heterogeneity

  11. [PLURAL THERAPEUTIC ITINERARIES].

    Science.gov (United States)

    Iorio, Silvia

    2015-01-01

    This article addresses the strategies employed by Nahua community of Mexixo to deal with health problems. Drawing on qualitative research, it discusses the choice of plural therapeutic itineraries, including the use of informal and formal healthcare.

  12. [Neutralizing Monoclonal and Chimeric Antibodies to Human IFN-γ].

    Science.gov (United States)

    Larina, M V; Aliev, T K; Solopova, O N; Pozdnyakova, L P; Korobova, S V; Yakimov, S A; Sveshnikov, P G; Dolgikh, D A; Kirpichnikov, M P

    2015-01-01

    Autoiminune disorders are chronic diseases characterized by abnormal immune response directed against self-antigens that leads to tissue damage and violation of its normal functioning. Such diseases often result in disability or even death of patients. Nowadays a number of monoclonal antibodies to pro-inflammatory cytokines and their receptors are successfully used for the targeted treatment of autoimmune diseases. One of the perspective targets in autoimmune disease therapy is interferon gamma, a key cytokine in Th1 cells differentiation, activation of macrophages, and inflammation. In the present work, 5 monoclonal antibodies to human IFN-γ were obtained. For the development of potential therapeutic agent, we have performed neutralizing activity and affinity analysis of the antibodies. Based on the data obtained, the monoclonal antibody F1 was selected. This antibody has a dissociation constant 1.7 x 10(-9) M and IC90 = 8.9 ± 2.0 nM measured upon antibody inhibition of the IFN-γ-induced HLA-DR expression on the surface of U937 cells. We have constructed a bicistronic vector for the production of recombinant chimeric Fab fragment F1 chim in E. coli cells. The recombinant chimeric Fab fragment Fl chim neutralizes IFN-γ activity in vitro and has a dissociation constant 1.8 x 10(-9) M.

  13. Antibody Derived Peptides for Detection of Ebola Virus Glycoprotein.

    Directory of Open Access Journals (Sweden)

    Luis Mario Rodríguez-Martínez

    Full Text Available Current Ebola virus (EBOV detection methods are costly and impractical for epidemic scenarios. Different immune-based assays have been reported for the detection and quantification of Ebola virus (EBOV proteins. In particular, several monoclonal antibodies (mAbs have been described that bind the capsid glycoprotein (GP of EBOV GP. However, the currently available platforms for the design and production of full-length mAbs are cumbersome and costly. The use of antibody fragments, rather than full-length antibodies, might represent a cost-effective alternative for the development of diagnostic and possibly even therapeutic alternatives for EBOV.We report the design and expression of three recombinant anti-GP mAb fragments in Escherichia coli cultures. These fragments contained the heavy and light variable portions of the three well-studied anti-GP full-length mAbs 13C6, 13F6, and KZ52, and are consequently named scFv-13C6, scFv-13F6, and Fab-KZ52, respectively. All three fragments exhibited specific anti-GP binding activity in ELISA experiments comparable to that of full-length anti-GP antibodies (i.e., the same order of magnitude and they are easily and economically produced in bacterial cultures.Antibody fragments might represent a useful, effective, and low cost alternative to full-length antibodies in Ebola related capture and diagnostics applications.

  14. FcγRII-binding Centyrins mediate agonism and antibody-dependent cellular phagocytosis when fused to an anti-OX40 antibody.

    Science.gov (United States)

    Zhang, Di; Whitaker, Brian; Derebe, Mehabaw G; Chiu, Mark L

    2018-01-23

    Immunostimulatory antibodies against the tumor necrosis factor receptors (TNFR) are emerging as promising cancer immunotherapies. The agonism activity of such antibodies depends on crosslinking to Fc gamma RIIB receptor (FcγRIIB) to enable the antibody multimerization that drives TNFR activation. Previously, Fc engineering was used to enhance the binding of such antibodies to Fcγ receptors. Here, we report the identification of Centyrins as alternative scaffold proteins with binding affinities to homologous FcγRIIB and FcγRIIA, but not to other types of Fcγ receptors. One Centyrin, S29, was engineered at distinct positions of an anti-OX40 SF2 antibody to generate bispecific and tetravalent molecules named as mAbtyrins. Regardless of the position of S29 on the SF2 antibody, SF2-S29 mAbtyrins could bind FcγRIIB and FcγRIIA specifically while maintaining binding to OX40 receptors. In a NFκB reporter assay, attachment of S29 Centyrin molecules at the C-termini, but not the N-termini, resulted in SF2 antibodies with increased agonism owing to FcγRIIB crosslinking. The mAbtyrins also showed agonism in T-cell activation assays with immobilized FcγRIIB and FcγRIIA, but this activity was confined to mAbtyrins with S29 specifically at the C-termini of antibody heavy chains. Furthermore, regardless of the position of the molecule, S29 Centyrin could equip an otherwise Fc-silent antibody with antibody-dependent cellular phagocytosis activity without affecting the antibody's intrinsic antibody-dependent cell-meditated cytotoxicity and complement-dependent cytotoxicity. In summary, the appropriate adoption FcγRII-binding Centyrins as functional modules represents a novel strategy to engineer therapeutic antibodies with improved functionalities.

  15. Novel Cross-Reactive Monoclonal Antibodies against Ebolavirus Glycoproteins Show Protection in a Murine Challenge Model.

    Science.gov (United States)

    Duehr, James; Wohlbold, Teddy John; Oestereich, Lisa; Chromikova, Veronika; Amanat, Fatima; Rajendran, Madhusudan; Gomez-Medina, Sergio; Mena, Ignacio; tenOever, Benjamin R; García-Sastre, Adolfo; Basler, Christopher F; Munoz-Fontela, Cesar; Krammer, Florian

    2017-08-15

    Out of an estimated 31,100 cases since their discovery in 1976, ebolaviruses have caused approximately 13,000 deaths. The vast majority (∼11,000) of these occurred during the 2013-2016 West African epidemic. Three out of five species in the genus are known to cause Ebola Virus Disease in humans. Several monoclonal antibodies against the ebolavirus glycoprotein are currently in development as therapeutics. However, there is still a paucity of monoclonal antibodies that can cross-react between the glycoproteins of different ebolavirus species, and the mechanism of these monoclonal antibody therapeutics is still not understood in detail. Here, we generated a panel of eight murine monoclonal antibodies (MAbs) utilizing a prime-boost vaccination regimen with a Zaire ebolavirus glycoprotein expression plasmid followed by infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. We tested the binding breadth of the resulting monoclonal antibodies using a set of recombinant surface glycoproteins from Reston, Taï Forest, Bundibugyo, Zaire, Sudan, and Marburg viruses and found two antibodies that showed pan-ebolavirus binding. An in vivo Stat2-/- mouse model was utilized to test the ability of these MAbs to protect from infection with a vesicular stomatitis virus expressing the Zaire ebolavirus glycoprotein. Several of our antibodies, including the broadly binding ones, protected mice from mortality despite lacking neutralization capability in vitro, suggesting their protection may be mediated by Fc-FcR interactions. Indeed, three antibodies displayed cellular phagocytosis and/or antibody-dependent cell-mediated cytotoxicity in vitro Our antibodies, specifically the two identified cross-reactive monoclonal antibodies (KL-2E5 and KL-2H7), might add to the understanding of anti-ebolavirus humoral immunity.IMPORTANCE This study describes the generation of a panel of novel anti-ebolavirus glycoprotein monoclonal antibodies, including two

  16. Tandem Native Mass-Spectrometry on Antibody-Drug Conjugates and Submillion da Antibody-Antigen Protein Assemblies on an Orbitrap EMR Equipped with a High-Mass Quadrupole Mass Selector

    NARCIS (Netherlands)

    Dyachenko, Andrey; Wang, Guanbo; Belov, Mike; Makarov, Alexander; De Jong, Rob N.; Van Den Bremer, Ewald T J; Parren, Paul W H I; Heck, Albert J R

    2015-01-01

    Native mass spectrometry is emerging as a powerful tool for the characterization of intact antibodies and antibody-based therapeutics. Here, we demonstrate new possibilities provided by the implementation of a high mass quadrupole mass selector on the recently introduced Orbitrap Exactive EMR mass

  17. Sterilization of therapeutic immunoadsorbents by ionizing radiation.

    Science.gov (United States)

    Sato, H; Kidaka, T; Hori, M

    1986-03-01

    The application of ionizing radiation (gamma-rays from 60Co) to sterilize therapeutic immunoadsorbents (IA)s was investigated. The IAs were porous bead carriers immobilizing anti-IgE antibodies and were irradiated in both the freeze-dried and precipitated (wet) states. The IgE removal (%), the IgE adsorption capacity of IA, was acceptable in terms of practical use even after an irradiation dose of 2.5 Mrad in the precipitated state; the anti-IgE antibody itself lost much of its activity, possibly because of intermolecular crosslinking of antibody molecules, after being irradiated with a dose at least of 0.5 Mrad. In the freeze-dried state only IA consisting of CPG-1400 could tolerate a dose of 2.5 Mrad. Dose-survival curves were obtained using Bacillus pumilus spores in both the freeze-dried and precipitated IAs and the D-values were calculated to be respectively 0.27 and 0.31 Mrad. Thus, ionizing radiation may be applicable for sterilizing IAs in the precipitated state and in the freeze-dried state for an IA consisting of CPG-1400 although the initial bioburden on IA should be low.

  18. In vivo neutralization of α-cobratoxin with high-affinity llama single-domain antibodies (VHHs and a VHH-Fc antibody.

    Directory of Open Access Journals (Sweden)

    Gabrielle Richard

    Full Text Available Small recombinant antibody fragments (e.g. scFvs and VHHs, which are highly tissue permeable, are being investigated for antivenom production as conventional antivenoms consisting of IgG or F(ab'2 antibody fragments do not effectively neutralize venom toxins located in deep tissues. However, antivenoms composed entirely of small antibody fragments may have poor therapeutic efficacy due to their short serum half-lives. To increase serum persistence and maintain tissue penetration, we prepared low and high molecular mass antivenom antibodies. Four llama VHHs were isolated from an immune VHH-displayed phage library and were shown to have high affinity, in the low nM range, for α-cobratoxin (α-Cbtx, the most lethal component of Naja kaouthia venom. Subsequently, our highest affinity VHH (C2 was fused to a human Fc fragment to create a VHH2-Fc antibody that would offer prolonged serum persistence. After in planta (Nicotiana benthamiana expression and purification, we show that our VHH2-Fc antibody retained high affinity binding to α-Cbtx. Mouse α-Cbtx challenge studies showed that our highest affinity VHHs (C2 and C20 and the VHH2-Fc antibody effectively neutralized lethality induced by α-Cbtx at an antibody:toxin molar ratio as low as ca. 0.75×:1. Further research towards the development of an antivenom therapeutic involving these anti-α-Cbtx VHHs and VHH2-Fc antibody molecules should involve testing them as a combination, to determine whether they maintain tissue penetration capability and low immunogenicity, and whether they exhibit improved serum persistence and therapeutic efficacy.

  19. Interplay between Natural Killer Cells and Anti-HER2 Antibodies: Perspectives for Breast Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Aura Muntasell

    2017-11-01

    Full Text Available Overexpression of the human epidermal growth factor receptor 2 (HER2 defines a subgroup of breast tumors with aggressive behavior. The addition of HER2-targeted antibodies (i.e., trastuzumab, pertuzumab to chemotherapy significantly improves relapse-free and overall survival in patients with early-stage and advanced disease. Nonetheless, considerable proportions of patients develop resistance to treatment, highlighting the need for additional and co-adjuvant therapeutic strategies. HER2-specific antibodies can trigger natural killer (NK cell-mediated antibody-dependent cellular cytotoxicity and indirectly enhance the development of tumor-specific T cell immunity; both mechanisms contributing to their antitumor efficacy in preclinical models. Antibody-dependent NK cell activation results in the release of cytotoxic granules as well as the secretion of pro-inflammatory cytokines (i.e., IFNγ and TNFα and chemokines. Hence, NK cell tumor suppressive functions include direct cytolytic killing of tumor cells as well as the regulation of subsequent antitumor adaptive immunity. Albeit tumors with gene expression signatures associated to the presence of cytotoxic lymphocyte infiltrates benefit from trastuzumab-based treatment, NK cell-related biomarkers of response/resistance to HER2-specific therapeutic antibodies in breast cancer patients remain elusive. Several variables, including (i the configuration of the patient NK cell repertoire; (ii tumor molecular features (i.e., estrogen receptor expression; (iii concomitant therapeutic regimens (i.e., chemotherapeutic agents, tyrosine kinase inhibitors; and (iv evasion mechanisms developed by progressive breast tumors, have been shown to quantitatively and qualitatively influence antibody-triggered NK cell responses. In this review, we discuss possible interventions for restoring/enhancing the therapeutic activity of HER2 therapeutic antibodies by harnessing NK cell antitumor potential through

  20. Second antibody clearance of radiolabeled antibody in cancer radioimmunodetection.

    OpenAIRE

    Sharkey, R.M.; Primus, F J; Goldenberg, D M

    1984-01-01

    The imaging of tumors using radiolabeled antibodies previously has required the implementation of computer-assisted subtraction techniques to reduce background radioactivity. A decrease in radioactivity in the blood of hamsters bearing human colonic tumor xenografts has been achieved by administering a second antibody directed against a radiolabeled primary antibody to carcinoembryonic antigen (CEA). This method was found to reduce the level of blood radioactivity by a factor of 4 within 2 hr...

  1. CD44 antibodies and immune thrombocytopenia in the amelioration of murine inflammatory arthritis.

    Directory of Open Access Journals (Sweden)

    Patrick J Mott

    Full Text Available Antibodies to CD44 have been used to successfully ameliorate murine models of autoimmune disease. The most often studied disease model has been murine inflammatory arthritis, where a clear mechanism for the efficacy of CD44 antibodies has not been established. We have recently shown in a murine passive-model of the autoimmune disease immune thrombocytopenia (ITP that some CD44 antibodies themselves can induce thrombocytopenia in mice, and the CD44 antibody causing the most severe thrombocytopenia (IM7, also is known to be highly effective in ameliorating murine models of arthritis. Recent work in the K/BxN serum-induced model of arthritis demonstrated that antibody-induced thrombocytopenia reduced arthritis, causing us to question whether CD44 antibodies might primarily ameliorate arthritis through their thrombocytopenic effect. We evaluated IM7, IRAWB14.4, 5035-41.1D, KM201, KM114, and KM81, and found that while all could induce thrombocytopenia, the degree of protection against serum-induced arthritis was not closely related to the length or severity of the thrombocytopenia. CD44 antibody treatment was also able to reverse established inflammation, while thrombocytopenia induced by an anti-platelet antibody targeting the GPIIbIIIa platelet antigen, could not mediate this effect. While CD44 antibody-induced thrombocytopenia may contribute to some of its therapeutic effect against the initiation of arthritis, for established disease there are likely other mechanisms contributing to its efficacy. Humans are not known to express CD44 on platelets, and are therefore unlikely to develop thrombocytopenia after CD44 antibody treatment. An understanding of the relationship between arthritis, thrombocytopenia, and CD44 antibody treatment remains critical for continued development of CD44 antibody therapeutics.

  2. Discovery of functional monoclonal antibodies targeting G-protein-coupled receptors and ion channels.

    Science.gov (United States)

    Wilkinson, Trevor C I

    2016-06-15

    The development of recombinant antibody therapeutics is a significant area of growth in the pharmaceutical industry with almost 50 approved monoclonal antibodies on the market in the US and Europe. Despite this growth, however, certain classes of important molecular targets have remained intractable to therapeutic antibodies due to complexity of the target molecules. These complex target molecules include G-protein-coupled receptors and ion channels which represent a large potential target class for therapeutic intervention with monoclonal antibodies. Although these targets have typically been addressed by small molecule approaches, the exquisite specificity of antibodies provides a significant opportunity to provide selective modulation of these target proteins. Given this opportunity, substantial effort has been applied to address the technical challenges of targeting these complex membrane proteins with monoclonal antibodies. In this review recent progress made in the strategies for discovery of functional monoclonal antibodies for these challenging membrane protein targets is addressed. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  3. A high-yielding, generic fed-batch process for recombinant antibody production of GS-engineered cell lines

    DEFF Research Database (Denmark)

    Fan, Li; Zhao, Liang; Sun, Yating

    2009-01-01

    . Compared to batch cultures, the fed-batch technology generated the magnitude of the increase in cell yields (5 fold) and final antibody concentrations (4-8 fold). The majority of the increase in final antibody concentration was functions of the increased cell density and the prolonged culture time....... This generic and high-yielding fed-batch process would shorten development time, and ensure process stability, thereby facilitating the manufacture of therapeutic antibodies by GS-engineered cell lines....

  4. Generation of human antigen-specific monoclonal IgM antibodies using vaccinated "human immune system" mice

    NARCIS (Netherlands)

    Becker, P.D.; Legrand, N.; van Geelen, C.M.M.; Noerder, M.; Huntington, N.D.; Lim, A.; Yasuda, E.; Diehl, S.A.; Scheeren, F.A.; Ott, M.; Weijer, K.; Wedemeyer, H.; Di Santo, J.P.; Beaumont, T.; Guzman, C.A.; Spits, H.

    2010-01-01

    Passive transfer of antibodies not only provides immediate short-term protection against disease, but also can be exploited as a therapeutic tool. However, the 'humanization' of murine monoclonal antibodies (mAbs) is a time-consuming and expensive process that has the inherent drawback of

  5. Clinical relevance of anti-exenatide antibodies: safety, efficacy and cross-reactivity with long-term treatment

    NARCIS (Netherlands)

    Fineman, M.S.; Mace, K.F.; Diamant, M.; Darsow, T.; Cirincione, B.B.; Porter, T.K.B.; Kinninger, L.A.; Trautmann, M.E.

    2012-01-01

    Aims: Antibody formation to therapeutic peptides is common. This analysis characterizes the time-course and cross-reactivity of anti-exenatide antibodies and potential effects on efficacy and safety. Methods: Data from intent-to-treat patients in 12 controlled (n = 2225,12-52weeks) and 5

  6. How antibodies use complement to regulate antibody responses.

    Science.gov (United States)

    Sörman, Anna; Zhang, Lu; Ding, Zhoujie; Heyman, Birgitta

    2014-10-01

    Antibodies, forming immune complexes with their specific antigen, can cause complete suppression or several 100-fold enhancement of the antibody response. Immune complexes containing IgG and IgM may activate complement and in such situations also complement components will be part of the immune complex. Here, we review experimental data on how antibodies via the complement system upregulate specific antibody responses. Current data suggest that murine IgG1, IgG2a, and IgG2b upregulate antibody responses primarily via Fc-receptors and not via complement. In contrast, IgM and IgG3 act via complement and require the presence of complement receptors 1 and 2 (CR1/2) expressed on both B cells and follicular dendritic cells. Complement plays a crucial role for antibody responses not only to antigen complexed to antibodies, but also to antigen administered alone. Lack of C1q, but not of Factor B or MBL, severely impairs antibody responses suggesting involvement of the classical pathway. In spite of this, normal antibody responses are found in mice lacking several activators of the classical pathway (complement activating natural IgM, serum amyloid P component (SAP), specific intracellular adhesion molecule-grabbing non-integrin R1 (SIGN-R1) or C-reactive protein. Possible explanations to these observations will be discussed. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. High-throughput glycosylation analysis of therapeutic immunoglobulin G by capillary gel electrophoresis using a DNA analyzer.

    NARCIS (Netherlands)

    Reusch, D.; Haberger, M.; Kailich, T.; Heidenreich, A.K.; Kampe, M.; Bulau, P.; Wuhrer, M.

    2014-01-01

    The Fc glycosylation of therapeutic antibodies is crucial for their effector functions and their behavior in pharmacokinetics and pharmacodynamics. To monitor the Fc glycosylation in bioprocess development and characterization, high-throughput techniques for glycosylation analysis are needed. Here,

  8. Monoclonal antibodies to Pneumocystis carinii

    DEFF Research Database (Denmark)

    Kovacs, J A; Halpern, J L; Lundgren, B

    1989-01-01

    To increase understanding of the antigenic structure of Pneumocystis carinii, we developed monoclonal antibodies to rat and human P. carinii. The specificity of the antibodies was demonstrated by immunofluorescence and immunoblot studies. Only one of five monoclonal antibodies to rat P. carinii...... reacted with human P. carinii, and none of four monoclonal antibodies to human P. carinii reacted with rat P. carinii. Two antibodies to human P. carinii reacted by immunofluorescence with only one human P. carinii isolate. Immunoblot studies identified major antigens of rat P. carinii with molecular...... antigenically different. Further studies with these antibodies should increase understanding of the antigenic nature of P. carinii and of the interaction of P. carinii with its host....

  9. Lepidopteran cells, an alternative for the production of recombinant antibodies?

    Science.gov (United States)

    Cérutti, Martine; Golay, Josée

    2012-01-01

    Monoclonal antibodies are used with great success in many different therapeutic domains. In order to satisfy the growing demand and to lower the production cost of these molecules, many alternative systems have been explored. Among them, the baculovirus/insect cells system is a good candidate. This system is very safe, given that the baculoviruses have a highly restricted host range and they are not pathogenic to vertebrates or plants. But the major asset is the speed with which it is possible to obtain very stable recombinant viruses capable of producing fully active proteins whose glycosylation pattern can be modulated to make it similar to the human one. These features could ultimately make the difference by enabling the production of antibodies with very low costs. However, efforts are still needed, in particular to increase production rates and thus make this system commercially viable for the production of these therapeutic agents.

  10. Monoclonal Antibodies Radiolabeling with Rhenium-188 for Radioimmunotherapy

    Directory of Open Access Journals (Sweden)

    Licia Uccelli

    2017-01-01

    Full Text Available Rhenium-188, obtained from an alumina-based tungsten-188/rhenium-188 generator, is actually considered a useful candidate for labeling biomolecules such as antibodies, antibody fragments, peptides, and DNAs for radiotherapy. There is a widespread interest in the availability of labeling procedures that allow obtaining Re188-labeled radiopharmaceuticals for various therapeutic applications, in particular for the rhenium attachment to tumor-specific monoclonal antibodies (MoAbs for immunotherapy. Different approaches have been developed in order to obtain Re188-radioimmunoconjugates in high radiochemical purity starting from the generator eluted Re188ReO4-. The aim of this paper is to provide a short overview on Re188-labeled (MoAbs, focusing in particular on the radiolabeling methods, quality control of radioimmunoconjugates, and their in vitro stability for radioimmunotherapy (RIT, with particular reference to the most important contributions published in literature in this topic.

  11. Monoclonal Antibodies Radiolabeling with Rhenium-188 for Radioimmunotherapy.

    Science.gov (United States)

    Uccelli, Licia; Martini, Petra; Pasquali, Micol; Boschi, Alessandra

    2017-01-01

    Rhenium-188, obtained from an alumina-based tungsten-188/rhenium-188 generator, is actually considered a useful candidate for labeling biomolecules such as antibodies, antibody fragments, peptides, and DNAs for radiotherapy. There is a widespread interest in the availability of labeling procedures that allow obtaining 188Re-labeled radiopharmaceuticals for various therapeutic applications, in particular for the rhenium attachment to tumor-specific monoclonal antibodies (Mo)Abs for immunotherapy. Different approaches have been developed in order to obtain 188Re-radioimmunoconjugates in high radiochemical purity starting from the generator eluted [188Re]ReO4-. The aim of this paper is to provide a short overview on 188Re-labeled (Mo)Abs, focusing in particular on the radiolabeling methods, quality control of radioimmunoconjugates, and their in vitro stability for radioimmunotherapy (RIT), with particular reference to the most important contributions published in literature in this topic.

  12. Production of antibodies in plants: status after twenty years.

    Science.gov (United States)

    De Muynck, Benoit; Navarre, Catherine; Boutry, Marc

    2010-06-01

    Thanks to their potential to bind virtually all types of molecules; monoclonal antibodies are in increasing demand as therapeutics and diagnostics. To overcome the overloading of current production facilities, alternative expression systems have been developed, of which plants appear the most promising. In this review, we focus on the expression of monoclonal IgG or IgM in plant species. We analyse the data for 32 different antibodies expressed in various ways, differing in DNA construction, transformation method, signal peptide source, presence or absence of an endoplasmic reticulum retention sequence, host species and the organs tested, together resulting in 98 reported combinations. A large heterogeneity is found in the quantity and quality of the antibody produced. We discuss in more detail the strategy used to express both chains, the nature of the transcription promoters, subcellular localization and unintended proteolysis, when encountered.

  13. In Situ Liver Expression of HBsAg/CD3-Bispecific Antibodies for HBV Immunotherapy.

    Science.gov (United States)

    Kruse, Robert L; Shum, Thomas; Legras, Xavier; Barzi, Mercedes; Pankowicz, Frank P; Gottschalk, Stephen; Bissig, Karl-Dimiter

    2017-12-15

    Current therapies against hepatitis B virus (HBV) do not reliably cure chronic infection, necessitating new therapeutic approaches. The T cell response can clear HBV during acute infection, and the adoptive transfer of antiviral T cells during bone marrow transplantation can cure patients of chronic HBV infection. To redirect T cells to HBV-infected hepatocytes, we delivered plasmids encoding bispecific antibodies directed against the viral surface antigen (HBsAg) and CD3, expressed on almost all T cells, directly into the liver using hydrodynamic tail vein injection. We found a significant reduction in HBV-driven reporter gene expression (184-fold) in a mouse model of acute infection, which was 30-fold lower than an antibody only recognizing HBsAg. While bispecific antibodies triggered, in part, antigen-independent T cell activation, antibody production within hepatocytes was non-cytotoxic. We next tested the bispecific antibodies in a different HBV mouse model, which closely mimics the transcriptional template for HBV, covalently closed circular DNA (cccDNA). We found that the antiviral effect was noncytopathic, mediating a 495-fold reduction in HBsAg levels at day 4. At day 33, bispecific antibody-treated mice exhibited 35-fold higher host HBsAg immunoglobulin G (IgG) antibody production versus untreated groups. Thus, gene therapy with HBsAg/CD3-bispecific antibodies represents a promising therapeutic strategy for patients with HBV.

  14. Potent Human Monoclonal Antibodies against SARS CoV, Nipah and Hendra Viruses

    Science.gov (United States)

    Prabakaran, Ponraj; Zhongyu, Zhu; Xiao, Xiaodong; Biragyn, Arya; Dimitrov, Antony S.; Broder, Christopher C.; Dimitrov, Dimiter S.

    2009-01-01

    Polyclonal antibodies have a century-old history of being effective against some viruses; recently, monoclonal antibodies (mAbs) have also shown success. The humanized mAb Synagis (palivizumab) remains still the only mAb against respiratory syncytial virus (RSV) infections approved by the U.S. Food and Drug Administration (FDA). Recently, several potent human monoclonal antibodies (hmAbs) targeting the Severe Acute Respiratory Syndrome-Associated coronavirus (SARS CoV) S glycoproteins were developed quickly after the virus was identified in 2003. Among these antibodies, m396 and S230.15 exhibit exceptional potency and cross-reactivity as they neutralize isolates from the first and second outbreaks and from palm civets both in vitroand in mice. Similarly, the first fully hmAbs against two other paramyxoviruses, Hendra virus (HeV) and Nipah virus (NiV), which can cause up to 75% mortality, were recently developed; one of them, m102.4, shows exceptional cross-reactive potency against both NiV and HeV. Three-dimensional molecular structures of envelope glycoproteins from these viruses in complexes with antibodies and/or receptors were recently determined. Structural analyses along with other experiments have provided insights into the molecular mechanisms of receptor recognition and antibody neutralization, and suggested that these antibodies alone or in combination could successfully fight the viruses’ heterogeneity and mutability which is a major problem in the development of effective therapeutic agents against viruses, including therapeutic antibodies. PMID:19216624

  15. In Situ Liver Expression of HBsAg/CD3-Bispecific Antibodies for HBV Immunotherapy

    Directory of Open Access Journals (Sweden)

    Robert L. Kruse

    2017-12-01

    Full Text Available Current therapies against hepatitis B virus (HBV do not reliably cure chronic infection, necessitating new therapeutic approaches. The T cell response can clear HBV during acute infection, and the adoptive transfer of antiviral T cells during bone marrow transplantation can cure patients of chronic HBV infection. To redirect T cells to HBV-infected hepatocytes, we delivered plasmids encoding bispecific antibodies directed against the viral surface antigen (HBsAg and CD3, expressed on almost all T cells, directly into the liver using hydrodynamic tail vein injection. We found a significant reduction in HBV-driven reporter gene expression (184-fold in a mouse model of acute infection, which was 30-fold lower than an antibody only recognizing HBsAg. While bispecific antibodies triggered, in part, antigen-independent T cell activation, antibody production within hepatocytes was non-cytotoxic. We next tested the bispecific antibodies in a different HBV mouse model, which closely mimics the transcriptional template for HBV, covalently closed circular DNA (cccDNA. We found that the antiviral effect was noncytopathic, mediating a 495-fold reduction in HBsAg levels at day 4. At day 33, bispecific antibody-treated mice exhibited 35-fold higher host HBsAg immunoglobulin G (IgG antibody production versus untreated groups. Thus, gene therapy with HBsAg/CD3-bispecific antibodies represents a promising therapeutic strategy for patients with HBV.

  16. HIV therapy by a combination of broadly neutralizing antibodies in humanized mice.

    Science.gov (United States)

    Klein, Florian; Halper-Stromberg, Ariel; Horwitz, Joshua A; Gruell, Henning; Scheid, Johannes F; Bournazos, Stylianos; Mouquet, Hugo; Spatz, Linda A; Diskin, Ron; Abadir, Alexander; Zang, Trinity; Dorner, Marcus; Billerbeck, Eva; Labitt, Rachael N; Gaebler, Christian; Marcovecchio, Paola; Incesu, Reha-Baris; Eisenreich, Thomas R; Bieniasz, Paul D; Seaman, Michael S; Bjorkman, Pamela J; Ravetch, Jeffrey V; Ploss, Alexander; Nussenzweig, Michel C

    2012-12-06

    Human antibodies to human immunodeficiency virus-1 (HIV-1) can neutralize a broad range of viral isolates in vitro and protect non-human primates against infection. Previous work showed that antibodies exert selective pressure on the virus but escape variants emerge within a short period of time. However, these experiments were performed before the recent discovery of more potent anti-HIV-1 antibodies and their improvement by structure-based design. Here we re-examine passive antibody transfer as a therapeutic modality in HIV-1-infected humanized mice. Although HIV-1 can escape from antibody monotherapy, combinations of broadly neutralizing antibodies can effectively control HIV-1 infection and suppress viral load to levels below detection. Moreover, in contrast to antiretroviral therapy, the longer half-life of antibodies led to control of viraemia for an average of 60 days after cessation of therapy. Thus, combinations of potent monoclonal antibodies can effectively control HIV-1 replication in humanized mice, and should be re-examined as a therapeutic modality in HIV-1-infected individuals.

  17. Antibodies in infectious diseases: polyclonals, monoclonals and niche biotechnology.

    Science.gov (United States)

    Berry, Jody D; Gaudet, Ryan G

    2011-09-01

    Antibody preparations have a long history of providing protection from infectious diseases. Although antibodies remain the only natural host-derived defense mechanism capable of completely preventing infection, as products, they compete against inexpensive therapeutics such as antibiotics, small molecule inhibitors and active vaccines. The continued discovery in the monoclonal antibody (mAb) field of leads with broadened cross neutralization of viruses and demonstrable synergy of antibody with antibiotics for bacterial diseases, clearly show that innovation remains. The commercial success of mAbs in chronic disease has not been paralleled in infectious diseases for several reasons. Infectious disease immunotherapeutics are limited in scope as endemic diseases necessitate active vaccine development. Also, the complexity of these small markets draws the interest of niche companies rather than big pharmaceutical corporations. Lastly, the cost of goods for mAb therapeutics is inherently high for infectious agents due to the need for antibody cocktails, which better mimic polyclonal immunoglobulin preparations and prevent antigenic escape. In cases where vaccine or convalescent populations are available, current polyclonal hyperimmune immunoglobulin preparations (pIgG), with modern and highly efficient purification technology and standardized assays for potency, can make economic sense. Recent innovations to broaden the potency of mAb therapies, while reducing cost of production, are discussed herein. On the basis of centuries of effective use of Ab treatments, and with growing immunocompromised populations, the question is not whether antibodies have a bright future for infectious agents, but rather what formats are cost effective and generate safe and efficacious treatments to satisfy regulatory approval. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Kant and therapeutic privilege.

    Science.gov (United States)

    Brown, Chris

    2008-08-01

    Given Kant's exceptionless moral prohibition on lying, one might suspect that he is committed to a similar prohibition on withholding diagnostic and prognostic information from patients. I confirm this suspicion by adapting arguments against therapeutic privilege from his arguments against lying. However, I show that all these arguments are importantly flawed and submit that they should be rejected. A more compelling Kantian take on informed consent and therapeutic privilege is achievable, I argue, by focusing on Kant's duty of beneficence, which requires us to aim at furthering others' ends. But I show that there are some cases in which furthering a patient's ends requires withholding material medical information from her. Although I concede that these cases are probably quite rare, I conclude that the best Kantian thinking agrees with that of therapeutic privilege's advocates.

  19. Antibody drug conjugates - Trojan horses in the war on cancer.

    Science.gov (United States)

    Iyer, U; Kadambi, V J

    2011-01-01

    Antibody drug conjugates (ADCs) consist of an antibody attached to a cytotoxic drug by means of a linker. ADCs provide a way to couple the specificity of a monoclonal antibody (mAb) to the cytotoxicity of a small-molecule drug and, therefore, are promising new therapies for cancer. ADCs are prodrugs that are inactive in circulation but exert their cytotoxicity upon binding to the target cancer cell. Earlier unsuccessful attempts to generate ADCs with therapeutic value have emphasized the important role each component plays in determining the efficacy and safety of the final ADC. Scientific advances in engineering antibodies for maximum efficacy as anticancer agents, identification of highly cytotoxic molecules, and generation of linkers with increased stability in circulation have all contributed to the development of the many ADCs that are currently in clinical trials. This review discusses parameters that guide the selection of the components of an ADC to increase its therapeutic window, provides a brief look at ADCs currently in clinical trials, and discusses future challenges in this field. Copyright © 2011. Published by Elsevier Inc.

  20. Protein Engineering: A New Frontier for Biological Therapeutics

    Science.gov (United States)

    Tobin, Peter H.; Richards, David H.; Callender, Randolph A.

    2016-01-01

    Protein engineering holds the potential to transform the metabolic drug landscape through the development of smart, stimulus-responsive drug systems. Protein therapeutics are a rapidly expanding segment of Food and Drug Administration approved drugs that will improve clinical outcomes over the long run. Engineering of protein therapeutics is still in its infancy, but recent general advances in protein engineering capabilities are being leveraged to yield improved control over both pharmacokinetics and pharmacodynamics. Stimulus-responsive protein therapeutics are drugs which have been designed to be metabolized under targeted conditions. Protein engineering is being utilized to develop tailored smart therapeutics with biochemical logic. This review focuses on applications of targeted drug neutralization, stimulus-responsive engineered protein prodrugs, and emerging multicomponent smart drug systems (e.g., antibody-drug conjugates, responsive engineered zymogens, prospective biochemical logic smart drug systems, drug buffers, and network medicine applications). PMID:25495737

  1. Antibodies against antibodies: immunogenicity of adalimumab as a model

    NARCIS (Netherlands)

    van Schouwenburg, P.A.

    2012-01-01

    Upon repeated adalimumab exposure part of the patients start to produce ADA. The antibody response is polyclonal and consists mainly of antibodies of IgG1 and IgG4 isotype. In the majority of ADA positive patients ADA are already produced within the first 28 weeks of treatment and in part of the

  2. Lymphedema and Therapeutic Lymphangiogenesis

    Directory of Open Access Journals (Sweden)

    Yukihiro Saito

    2013-01-01

    Full Text Available Lymphedema is a disorder of the lymphatic vascular system characterized by impaired lymphatic return and swelling of the extremities. Lymphedema is divided into primary and secondary forms based on the underlying etiology. Despite substantial advances in both surgical and conservative techniques, therapeutic options for the management of lymphedema are limited. Although rarely lethal, lymphedema is a disfiguring and disabling condition with an associated decrease in the quality of life. The recent impressive expansion of knowledge on the molecular mechanisms governing lymphangiogenesis provides new possibilities for the treatment of lymphedema. This review highlights the lymphatic biology, the pathophysiology of lymphedema, and the therapeutic lymphangiogenesis using hepatocyte growth factor.

  3. Therapeutic development in psoriasis.

    Science.gov (United States)

    Sobell, Jeffrey M; Leonardi, Craig L

    2014-06-01

    Advances in molecular biology have provided the basis for development of new therapeutic approaches to psoriasis. New, more effective therapies target specific molecules in the inflammatory cascade involved in the pathogenesis of psoriasis.The biologic era of psoriasis therapy began with inhibitors of T-cell activation, tumor necrosis factor-α, and interleukin (IL)-12/23. Continued investigation has led to therapies and therapeutic candidates that target IL-17, IL-23, phosphodiesterase-4, and isomers of Janus kinase. 2014 by Frontline Medical Communications Inc.

  4. Therapeutic HIV Peptide Vaccine

    DEFF Research Database (Denmark)

    Fomsgaard, Anders

    2015-01-01

    Therapeutic vaccines aim to control chronic HIV infection and eliminate the need for lifelong antiretroviral therapy (ART). Therapeutic HIV vaccine is being pursued as part of a functional cure for HIV/AIDS. We have outlined a basic protocol for inducing new T cell immunity during chronic HIV-1...... infection directed to subdominant conserved HIV-1 epitopes restricted to frequent HLA supertypes. The rationale for selecting HIV peptides and adjuvants are provided. Peptide subunit vaccines are regarded as safe due to the simplicity, quality, purity, and low toxicity. The caveat is reduced immunogenicity...

  5. Mechanism of action and in vivo efficacy of a human-derived antibody against Staphylococcus aureus α-hemolysin.

    Science.gov (United States)

    Foletti, Davide; Strop, Pavel; Shaughnessy, Lee; Hasa-Moreno, Adela; Casas, Meritxell Galindo; Russell, Marcella; Bee, Christine; Wu, Si; Pham, Amber; Zeng, Zhilan; Pons, Jaume; Rajpal, Arvind; Shelton, Dave

    2013-05-27

    The emergence and spread of multi-drug-resistant strains of Staphylococcus aureus in hospitals and in the community emphasize the urgency for the development of novel therapeutic interventions. Our approach was to evaluate the potential of harnessing the human immune system to guide the development of novel therapeutics. We explored the role of preexisting antibodies against S. aureus α-hemolysin in the serum of human individuals by isolating and characterizing one antibody with a remarkably high affinity to α-hemolysin. The antibody provided protection in S. aureus pneumonia, skin, and bacteremia mouse models of infection and also showed therapeutic efficacy when dosed up to 18 h post-infection in the pneumonia model. Additionally, in pneumonia and bacteremia animal models, the therapeutic efficacy of the α-hemolysin antibody appeared additive to the antibiotic linezolid. To better understand the mechanism of action of this isolated antibody, we solved the crystal structure of the α-hemolysin:antibody complex. To our knowledge, this is the first report of the crystal structure of the α-hemolysin monomer. The structure of the complex shows that the antibody binds α-hemolysin between the cap and the rim domains. In combination with biochemical data, the structure suggests that the antibody neutralizes the activity of the toxin by preventing binding to the plasma membrane of susceptible host cells. The data presented here suggest that protective antibodies directed against S. aureus molecules exist in some individuals and that such antibodies have a therapeutic potential either alone or in combination with antibiotics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Complement inhibition enables tumor delivery of LCMV glycoprotein pseudotyped viruses in the presence of antiviral antibodies

    Directory of Open Access Journals (Sweden)

    Laura Evgin

    2016-01-01

    Full Text Available The systemic delivery of therapeutic viruses, such as oncolytic viruses or vaccines, is limited by the generation of neutralizing antibodies. While pseudotyping of rhabdoviruses with the lymphocytic choriomeningitis virus glycoprotein has previously allowed for multiple rounds of delivery in mice, this strategy has not translated to other animal models. For the first time, we provide experimental evidence that antibodies generated against the lymphocytic choriomeningitis virus glycoprotein mediate robust complement-dependent viral neutralization via activation of the classical pathway. We show that this phenotype can be capitalized upon to deliver maraba virus pseudotyped with the lymphocytic choriomeningitis virus glycoprotein in a Fischer rat model in the face of neutralizing antibody through the use of complement modulators. This finding changes the understanding of the humoral immune response to arenaviruses, and also describes methodology to deliver viral vectors to their therapeutic sites of action without the interference of neutralizing antibody.

  7. CXCR4-specific Nanobodies as potential therapeutics for WHIM syndrome

    DEFF Research Database (Denmark)

    de Wit, Raymond H; Heukers, Raimond; Brink, Hendrik

    2017-01-01

    effective approach, we tested the potency and efficacy of CXCR4-specific Nanobodies on inhibiting CXCR4-WHIM mutants. Nanobodies(®) are therapeutic proteins based on the smallest functional fragments of heavy chain antibodies. They combine the advantages of small-molecule drugs and antibody......-based therapeutics due to their relative small size, high stability and high affinity. We compared the potential of monovalent and bivalent CXCR4-specific Nanobodies to inhibit CXCL12-induced CXCR4-WHIM-mediated signaling with the small molecule clinical candidate AMD3100. The CXCR4-targeting Nanobodies displace......WHIM syndrome is a rare congenital immunodeficiency disease, named after its main clinical manifestations: Warts, Hypogammaglobulinemia, Infections and Myelokathexis. The disease is primarily caused by C-terminal truncation mutations of the chemokine receptor CXCR4. Consequently, these CXCR4-WHIM...

  8. Overcoming Instability of Antibody-Nanomaterial Conjugates: Next Generation Targeted Nanomedicines Using Bispecific Antibodies.

    Science.gov (United States)

    Howard, Christopher B; Fletcher, Nicholas; Houston, Zachary H; Fuchs, Adrian V; Boase, Nathan R B; Simpson, Joshua D; Raftery, Lyndon J; Ruder, Tim; Jones, Martina L; de Bakker, Christopher J; Mahler, Stephen M; Thurecht, Kristofer J

    2016-08-01

    Targeted nanomaterials promise improved therapeutic efficacy, however their application in nanomedicine is limited due to complexities associated with protein conjugations to synthetic nanocarriers. A facile method to generate actively targeted nanomaterials is developed and exemplified using polyethylene glycol (PEG)-functional nanostructures coupled to a bispecific antibody (BsAb) with dual specificity for methoxy PEG (mPEG) epitopes and cancer targets such as epidermal growth factor receptor (EGFR). The EGFR-mPEG BsAb binds with high affinity to recombinant EGFR (KD : 1 × 10(-9) m) and hyperbranched polymer (HBP) consisting of mPEG (KD : 10 × 10(-9) m) and demonstrates higher avidity for HBP compared to linear mPEG. The binding of BsAb-HBP bioconjugate to EGFR on MDA-MB-468 cancer cells is investigated in vitro using a fluorescently labeled polymer, and in in vivo xenograft models by small animal optical imaging. The antibody-targeted nanostructures show improved accumulation in tumor cells compared to non-targeted nanomaterials. This demonstrates a facile approach for tuning targeting ligand density on nanomaterials, by modulating surface functionality. Antibody fragments are tethered to the nanomaterial through simple mixing prior to administration to animals, overcoming the extensive procedures encountered for developing targeted nanomedicines. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Therapeutic HPV DNA vaccines

    Science.gov (United States)

    Lin, Ken; Roosinovich, Elena; Ma, Barbara; Hung, Chien-Fu

    2010-01-01

    It is now well established that most cervical cancers are causally associated with HPV infection. This realization has led to efforts to control HPV-associated malignancy through prevention or treatment of HPV infection. Currently, commercially available HPV vaccines are not designed to control established HPV infection and associated premalignant and malignant lesions. To treat and eradicate pre-existing HPV infections and associated lesions which remain prevalent in the U.S. and worldwide, effective therapeutic HPV vaccines are needed. DNA vaccination has emerged as a particularly promising form of therapeutic HPV vaccines due to its safety, stability and ability to induce antigen-specific immunity. This review focuses on improving the potency of therapeutic HPV vaccines through modification of dendritic cells (DCs) by [1] increasing the number of antigen-expressing/antigen-loaded DCs, [2] improving HPV antigen expression, processing and presentation in DCs, and [3] enhancing DC and T cell interaction. Continued improvement in therapeutic HPV DNA vaccines may ultimately lead to an effective DNA vaccine for the treatment of HPV-associated malignancies. PMID:20066511

  10. Human Cell Line-Derived Monoclonal IgA Antibodies for Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Felix Hart

    2017-05-01

    Full Text Available IgA antibodies have great potential to improve the functional diversity of current IgG antibody-based cancer immunotherapy options. However, IgA production and purification is not well established, which can at least in part be attributed to the more complex glycosylation as compared to IgG antibodies. IgA antibodies possess up to five N-glycosylation sites within their constant region of the heavy chain as compared to one site for IgG antibodies. The human GlycoExpress expression system was developed to produce biotherapeutics with optimized glycosylation and used here to generate a panel of IgA isotype antibodies directed against targets for solid (TA-mucin 1, Her2, EGFR, Thomsen–Friedenreich and hematological (CD20 cancer indications. The feasibility of good manufacturing practice was shown by the production of 11 g IgA within 35 days in a one liter perfusion bioreactor, and IgA antibodies in high purity were obtained after purification. The monoclonal IgA antibodies possessed a high sialylation degree, and no non-human glycan structures were detected. Kinetic analysis revealed increased avidity antigen binding for IgA dimers as compared to monomeric antibodies. The IgA antibodies exhibited potent Fab- and Fc-mediated functionalities against cancer cell lines, whereby especially granulocytes are recruited. Therefore, for patients who do not sufficiently benefit from therapeutic IgG antibodies, IgA antibodies may complement current regiment options and represent a promising strategy for cancer immunotherapy. In conclusion, a panel of novel biofunctional IgA antibodies with human glycosylation was successfully generated.

  11. Educational paper: Primary antibody deficiencies

    NARCIS (Netherlands)

    G.J.A. Driessen (Gertjan); M. van der Burg (Mirjam)

    2011-01-01

    textabstractPrimary antibody deficiencies (PADs) are the most common primary immunodeficiencies and are characterized by a defect in the production of normal amounts of antigen-specific antibodies. PADs represent a heterogeneous spectrum of conditions, ranging from often asymptomatic selective IgA

  12. Antibodies and Plasmodium falciparum merozoites

    NARCIS (Netherlands)

    Ramasamy, R; Ramasamy, M; Yasawardena, S

    There is considerable interest in using merozoite proteins in a vaccine against falciparum malaria. Observations that antibodies to merozoite surface proteins block invasion are a basis for optimism. This article draws attention to important and varied aspects of how antibodies to Plasmodium

  13. Red Blood Cell Antibody Identification

    Science.gov (United States)

    ... antibodies may or may not be associated with adverse reactions, and identification of the specific type of RBC ... the only things that can cause a transfusion reaction. The recipient's immune ... or to drugs that the donor may have taken. Rarely, antibodies in the plasma ...

  14. Ultrafast and high-throughput N-glycan analysis for monoclonal antibodies

    OpenAIRE

    Yang, Xiaoyu; Kim, Sunnie Myung; Ruzanski, Richard; Chen, Yuetian; Moses, Sarath; Ling, Wai Lam; Li, Xiaojuan; Wang, Shao-Chun; Li, Huijuan; Ambrogelly, Alexandre; Richardson, Daisy; Shameem, Mohammed

    2016-01-01

    Glycosylation is a critical attribute for development and manufacturing of therapeutic monoclonal antibodies (mAbs) in the pharmaceutical industry. Conventional antibody glycan analysis is usually achieved by the 2-aminobenzamide (2-AB) hydrophilic interaction liquid chromatography (HILIC) method following the release of glycans. Although this method produces satisfactory results, it has limited use for screening a large number of samples because it requires expensive reagents and takes sever...

  15. C-C chemokine receptor-7 mediated endocytosis of antibody cargoes into intact cells

    OpenAIRE

    Charest-Morin, Xavier; P?pin, R?my; Gagn?-Henley, Ang?lique; Morissette, Guillaume; Lodge, Robert; Marceau, Fran?ois

    2013-01-01

    The C–C chemokine receptor-7 (CCR7) is a G protein coupled receptor that has a role in leukocyte homing, but that is also expressed in aggressive tumor cells. Preclinical research supports that CCR7 is a valid target in oncology. In view of the increasing availability of therapeutic monoclonal antibodies that carry cytotoxic cargoes, we studied the feasibility of forcing intact cells to internalize known monoclonal antibodies by exploiting the cycle of endocytosis and recycling triggered by t...

  16. Molecular basis of high viscosity in concentrated antibody solutions: Strategies for high concentration drug product development

    OpenAIRE

    Tomar, Dheeraj S.; Kumar, Sandeep; Singh, Satish K.; Goswami, Sumit; Li, Li

    2016-01-01

    Effective translation of breakthrough discoveries into innovative products in the clinic requires proactive mitigation or elimination of several drug development challenges. These challenges can vary depending upon the type of drug molecule. In the case of therapeutic antibody candidates, a commonly encountered challenge is high viscosity of the concentrated antibody solutions. Concentration-dependent viscosity behaviors of mAbs and other biologic entities may depend on pairwise and higher-or...

  17. Double seronegative myasthenia gravis with anti-LRP 4 antibodies.

    Science.gov (United States)

    Zouvelou, Vasiliki; Zisimopoulou, Paraskevi; Rentzos, Michael; Karandreas, Nikos; Evangelakou, Panagiota; Stamboulis, Eleftherios; Tzartos, Socrates J

    2013-07-01

    About 10% of patients with generalized myasthenia gravis do not have detectable antibodies to acetylcholine receptor or muscle specific kinase (double seronegative myasthenia). The presence of anti-low density lipoprotein receptor-related protein 4 antibodies (LRP4 Abs) has recently been reported in variable proportion of double seronegative cases. We report the presenting characteristics of two double seronegative myasthenic patients from Greece with anti-LRP4 antibodies shortly after disease onset. The first patient, a 52-year-old male, presented with a one month history of isolated neck extensor weakness; the second patient is a 52-year-old female with three months history of ocular-bulbar-cervical myasthenic weakness. Both patients presented with mild severity and responded promptly and adequately to pyridostigmine. In the female patient thymic residual tissue was detected on CT of the mediastinum. She underwent thymectomy, and histological examination revealed follicular hyperplasia. This is the first clinical report of the presenting features of newly diagnosed myasthenia with anti-LRP4 antibodies. The clinical and therapeutic implications of the anti-LRP4 antibody positivity remain to be clarified. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Homogeneous plate based antibody internalization assay using pH sensor fluorescent dye.

    Science.gov (United States)

    Nath, Nidhi; Godat, Becky; Zimprich, Chad; Dwight, Stephen J; Corona, Cesear; McDougall, Mark; Urh, Marjeta

    2016-04-01

    Receptor-mediated antibody internalization is a key mechanism underlying several anti-cancer antibody therapeutics. Delivering highly toxic drugs to cancer cells, as in the case of antibody drug conjugates (ADCs), efficient removal of surface receptors from cancer cells and changing the pharmacokinetics profile of the antibody drugs are some of key ways that internalization impacts the therapeutic efficacy of the antibodies. Over the years, several techniques have been used to study antibody internalization including radiolabels, fluorescent microscopy, flow cytometry and cellular toxicity assays. While these methods allow analysis of internalization, they have limitations including a multistep process and limited throughput and are generally endpoint assays. Here, we present a new homogeneous method that enables time and concentration dependent measurements of antibody internalization. The method uses a new hydrophilic and bright pH sensor dye (pHAb dye), which is not fluorescent at neutral pH but becomes highly fluorescent at acidic pH. For receptor mediated antibody internalization studies, antibodies against receptors are conjugated with the pHAb dye and incubated with the cells expressing the receptors. Upon binding to the receptor, the dyes conjugated to the antibody are not fluorescent because of the neutral pH of the media, but upon internalization and trafficking into endosomal and lysosomal vesicles the pH drops and dyes become fluorescent. The enabling attributes of the pHAb dyes are the hydrophilic nature to minimize antibody aggregation and bright fluorescence at acidic pH which allows development of simple plate based assays using a fluorescent reader. Using two different therapeutic antibodies--Trastuzumab (anti-HER2) and Cetuximab (anti-EGFR)--we show labeling with pHAb dye using amine and thiol chemistries and impact of chemistry and dye to antibody ration on internalization. We finally present two new approaches using the pHAb dye, which will be

  19. Potential immunological markers for diagnosis and therapeutic assessment of toxocariasis

    Directory of Open Access Journals (Sweden)

    Guita Rubinsky-Elefant

    2011-04-01

    Full Text Available In human toxocariasis, there are few approaches using immunological markers for diagnosis and therapeutic assessment. An immunoblot (IB assay using excretory-secretory Toxocara canis antigen was standardized for monitoring IgG, IgE and IgA antibodies in 27 children with toxocariasis (23 visceral, three mixed visceral and ocular, and one ocular form for 22-116 months after chemotherapy. IB sensitivity was 100% for IgG antibodies to bands of molecular weight 29-38, 48-54, 95-116, 121-162, >205 kDa, 80.8% for IgE to 29-38, 48-54, 95-121, > 205 kDa, and 65.4% for IgA to 29-38, 48-54, 81-93 kDa. Candidates for diagnostic markers should be IgG antibodies to bands of low molecular weight (29-38 and 48-54 kDa. One group of patients presented the same antibody reactivity to all bands throughout the follow-up study; in the other group, antibodies decayed partially or completely to some or all bands, but these changes were not correlated with time after chemotherapy. Candidates for monitoring patients after chemotherapy may be IgG antibodies to > 205 kDa fractions, IgA to 29-38, 48-54, 81-93 kDa and IgE to 95-121 kDa. Further identification of antigen epitopes related to these markers will allow the development of sensitive and specific immunoassays for the diagnosis and therapeutic assessment of toxocariasis.

  20. A novel human anti-interleukin-1β neutralizing monoclonal antibody showing in vivo efficacy.

    Science.gov (United States)

    Goh, Angeline X H; Bertin-Maghit, Sebastien; Ping Yeo, Siok; Ho, Adrian W S; Derks, Heidi; Mortellaro, Alessandra; Wang, Cheng-I

    2014-01-01

    The pro-inflammatory cytokine interleukin (IL)-1β is a clinical target in many conditions involving dysregulation of the immune system; therapeutics that block IL-1β have been approved to treat diseases such as rheumatoid arthritis (RA), neonatal onset multisystem inflammatory diseases, cryopyrin-associated periodic syndromes, active systemic juvenile idiopathic arthritis. Here, we report the generation and engineering of a new fully human antibody that binds tightly to IL-1β with a neutralization potency more than 10 times higher than that of the marketed antibody canakinumab. After affinity maturation, the derived antibody shows a>30-fold increased affinity to human IL-1β compared with its parent antibody. This anti-human IL-1β IgG also cross-reacts with mouse and monkey IL-1β, hence facilitating preclinical development. In a number of mouse models, this antibody efficiently reduced or abolished signs of disease associated with IL-1β pathology. Due to its high affinity for the cytokine and its potency both in vitro and in vivo, we propose that this novel fully human anti-IL-1β monoclonal antibody is a promising therapeutic candidate and a potential alternative to the current therapeutic arsenal.

  1. Analysing saturable antibody binding based on serum data and pharmacokinetic modelling

    Science.gov (United States)

    Kletting, Peter; Kiryakos, Hady; Reske, Sven N.; Glatting, Gerhard

    2011-01-01

    In radioimmunotherapy, organ dose calculations are frequently based on pretherapeutic biodistribution measurements, assuming equivalence between pretherapeutic and therapeutic biodistribution. However, when saturation of antibody binding sites is important, this assumption might not be justified. Residual antibody and different amounts of administered antibody may lead to a considerably altered therapeutic biodistribution. In this study we developed a method based on serum activity measurements to investigate this effect in radioimmunotherapy with 90Y-labelled anti-CD66 antibody. Pretherapeutic and therapeutic serum activity data of ten patients with acute leukaemia were fitted to a set of four parsimonious pharmacokinetic models. All models included the key mechanisms of antibody binding, immunoreactivity and degradation; however, they differed with respect to linear or nonlinear binding and global or individual fitting of the model parameters. The empirically most supported model was chosen according to the corrected Akaike information criterion. The nonlinear models were most supported by the data (sum of probabilities ≈100%). Using the presented method, we identified relevant saturable binding for radioimmunotherapy with 90Y-labelled anti-CD66 antibody solely based on serum data. This general method may also be applicable to investigate other systems where saturation of binding sites might be important.

  2. Novel conformation-specific monoclonal antibodies against amyloidogenic forms of transthyretin.

    Science.gov (United States)

    Higaki, Jeffrey N; Chakrabartty, Avi; Galant, Natalie J; Hadley, Kevin C; Hammerson, Bradley; Nijjar, Tarlochan; Torres, Ronald; Tapia, Jose R; Salmans, Joshua; Barbour, Robin; Tam, Stephen J; Flanagan, Ken; Zago, Wagner; Kinney, Gene G

    2016-06-01

    Transthyretin amyloidosis (ATTR amyloidosis) is caused by the misfolding and deposition of the transthyretin (TTR) protein and results in progressive multi-organ dysfunction. TTR epitopes exposed by dissociation and misfolding are targets for immunotherapeutic antibodies. We developed and characterized antibodies that selectively bound to misfolded, non-native conformations of TTR. Antibody clones were generated by immunizing mice with an antigenic peptide comprising a cryptotope within the TTR sequence and screened for specific binding to non-native TTR conformations, suppression of in vitro TTR fibrillogenesis, promotion of antibody-dependent phagocytic uptake of mis-folded TTR and specific immunolabeling of ATTR amyloidosis patient-derived tissue. Four identified monoclonal antibodies were characterized. These antibodies selectively bound the target epitope on monomeric and non-native misfolded forms of TTR and strongly suppressed TTR fibril formation in vitro. These antibodies bound fluorescently tagged aggregated TTR, targeting it for phagocytic uptake by macrophage THP-1 cells, and amyloid-positive TTR deposits in heart tissue from patients with ATTR amyloidosis, but did not bind to other types of amyloid deposits or normal tissue. Conformation-specific anti-TTR antibodies selectively bind amyloidogenic but not native TTR. These novel antibodies may be therapeutically useful in preventing deposition and promoting clearance of TTR amyloid and in diagnosing TTR amyloidosis.

  3. Antibodies Targeting Closely Adjacent or Minimally Overlapping Epitopes Can Displace One Another.

    Directory of Open Access Journals (Sweden)

    Yasmina Noubia Abdiche

    Full Text Available Here we describe how real-time label-free biosensors can be used to identify antibodies that compete for closely adjacent or minimally overlapping epitopes on their specific antigen via a mechanism of antibody displacement. By kinetically perturbing one another's binding towards their antigen via the formation of a transient trimolecular complex, antibodies can displace one another in a fully reversible and dose-dependent manner. Displacements can be readily identified when epitope binning assays are performed in a classical sandwich assay format whereby a solution antibody (analyte is tested for binding to its antigen that is first captured via an immobilized antibody (ligand because an inverted sandwiching response is observed when an analyte displaces a ligand, signifying the antigen's unusually rapid dissociation from its ligand. In addition to classifying antibodies within a panel in terms of their ability to block or sandwich pair with one another, displacement provides a hybrid mechanism of competition. Using high-throughput epitope binning studies we demonstrate that displacements can be observed on any target, if the antibody panel contains appropriate epitope diversity. Unidirectional displacements occurring between disparate-affinity antibodies can generate apparent asymmetries in a cross-blocking experiment, confounding their interpretation. However, examining competition across a wide enough concentration range will often reveal that these displacements are reversible. Displacement provides a gentle and efficient way of eluting antigen from an otherwise high affinity binding partner which can be leveraged in designing reagents or therapeutic antibodies with unique properties.

  4. Expression of recombinant antibody (single chain antibody fragment) in transgenic plant Nicotiana tabacum cv. Xanthi.

    Science.gov (United States)

    Dobhal, S; Chaudhary, V K; Singh, A; Pandey, D; Kumar, A; Agrawal, S

    2013-12-01

    Plants offer an alternative inexpensive and convenient technology for large scale production of recombinant proteins especially recombinant antibodies (plantibodies). In this paper, we describe the expression of a model single chain antibody fragment (B6scFv) in transgenic tobacco. Four different gene constructs of B6scFv with different target signals for expression in different compartments of a tobacco plant cell with and without endoplasmic reticulum (ER) retention signal were used. Agrobacterium mediated plant transformation of B6scFv gene was performed with tobacco leaf explants and the gene in regenerated plants was detected using histochemical GUS assay and PCR. The expression of B6scFv gene was detected by western blotting and the recombinant protein was purified from putative transgenic tobacco plants using metal affinity chromatography. The expression level of recombinant protein was determined by indirect enzyme-linked immunosorbent assay. The highest accumulation of protein was found up to 3.28 % of the total soluble protein (TSP) in plants expressing B6scFv 1003 targeted to the ER, and subsequently expression of 2.9 % of TSP in plants expressing B6scFv 1004 (with target to apoplast with ER retention signal). In contrast, lower expression of 0.78 and 0.58 % of TSP was found in plants expressing antibody fragment in cytosol and apoplast, without ER retention signal. The described method/system could be used in the future for diverse applications including expression of other recombinant molecules in plants for immunomodulation, obtaining pathogen resistance against plant pathogens, altering metabolic pathways and also for the expression of different antibodies of therapeutic and diagnostic uses.

  5. Chimeric antigen receptors and bispecific antibodies to retarget T cells in pediatric oncology.

    Science.gov (United States)

    Suzuki, Maya; Curran, Kevin J; Cheung, Nai-Kong V

    2015-08-01

    Cancer immunotherapy using antigen-specific T cells has broad therapeutic potential. Chimeric antigen receptors and bispecific antibodies can redirect T cells to kill tumors without human leukocyte antigens (HLA) restriction. Key determinants of clinical potential include the choice of target antigen, antibody specificity, antibody affinity, tumor accessibility, T cell persistence, and tumor immune evasion. For pediatric cancers, additional constraints include their propensity for bulky metastatic disease and the concern for late toxicities from treatment. Nonetheless, the recent preclinical and clinical developments of these T cell based therapies are highly encouraging. © 2015 Wiley Periodicals, Inc.

  6. From monoclonal antibodies to chimeric antigen receptors for the treatment of human malignancies.

    Science.gov (United States)

    Caruana, Ignazio; Diaconu, Iulia; Dotti, Gianpietro

    2014-10-01

    Monoclonal antibodies (mAbs) and their directly derived cell-based application known as chimeric antigen receptors (CARs) ensue from the need to develop novel therapeutic strategies that retain high anti-tumor activity, but carry reduced toxicity compared to conventional chemo- and radiotherapies. In this concise review article, we will summarize the application of antibodies designed to target antigens expressed by tumor cells, and the transition from these antibodies to the generation of CARs. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Structural understanding of stabilization patterns in engineered bispecific Ig-like antibody molecules

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Jacob L.; Arndt, Joseph W.; Hanf, Karl; Li, Guohui; Hall, Janine; Demarest, Stephen; Huang, Flora; Wu, Xiufeng; Miller, Brian; Glaser, Scott; Fernandez, Erik J.; Wang, Deping; Lugovskoy, Alexey; (UV); (Biogen)

    2010-01-12

    Bispecific immunoglobulin-like antibodies capable of engaging multiple antigens represent a promising new class of therapeutic agents. Engineering of these molecules requires optimization of the molecular properties of one of the domain components. Here, we present a detailed crystallographic and computational characterization of the stabilization patterns in the lymphotoxin-beta receptor (LT{beta}R) binding Fv domain of an anti-LT{beta}R/anti-TNF-related apoptosis inducing ligand receptor-2 (TRAIL-R2) bispecific immunoglobulin-like antibody. We further describe a new hierarchical structure-guided approach toward engineering of antibody-like molecules to enhance their thermal and chemical stability.

  8. Production of antibodies in plants and their use for global health.

    Science.gov (United States)

    Fischer, Rainer; Twyman, Richard M; Schillberg, Stefan

    2003-01-30

    Recombinant antibodies can be used to diagnose, treat and prevent disease by exploiting their specific antigen-binding activities. A large number of drugs currently in development are recombinant antibodies and most of these are produced in cultured rodent cells. Although such cells produce authentic functional products, they are expensive, difficult to scale-up and may contain human pathogens. Plants represent a cost-effective, convenient and safe alternative production system and are slowly gaining acceptance. Five plant-derived therapeutic recombinant antibodies (plantibodies) are undergoing clinical evaluation, three of which can be used as prophylactics.

  9. Multistage vector (MSV) therapeutics

    Science.gov (United States)

    Wolfram, Joy; Shen, Haifa; Ferrari, Mauro

    2015-01-01

    One of the greatest challenges in the field of medicine is obtaining controlled distribution of systemically administered therapeutic agents within the body. Indeed, biological barriers such as physical compartmentalization, pressure gradients, and excretion pathways adversely affect localized delivery of drugs to pathological tissue. The diverse nature of these barriers requires the use of multifunctional drug delivery vehicles that can overcome a wide range of sequential obstacles. In this review, we explore the role of multifunctionality in nanomedicine by primarily focusing on multistage vectors (MSVs). The MSV is an example of a promising therapeutic platform that incorporates several components, including a microparticle, nanoparticles, and small molecules. In particular, these components are activated in a sequential manner in order to successively address transport barriers. PMID:26264836

  10. Acylation of Therapeutic Peptides

    DEFF Research Database (Denmark)

    Trier, Sofie; Henriksen, Jonas Rosager; Jensen, Simon Bjerregaard

    Oral administration of therapeutic peptides could benefit millions of chronically ill people worldwide, through easier and less stigmatized therapy, and likely improve the long-term effects of currently widespread disease mismanagement. However, oral peptide delivery is a formidable task due......, but it is not widely studied in an oral context. As acylation furthermore increases interactions with the lipid membranes of mammalian cells, it offers several potential benefits for oral delivery of therapeutic peptides, and we hypothesize that tailoring the acylation may be used to optimize intestinal translocation...... to the harsh and selective gastrointestinal system, and development has lacked far behind injection therapy. Peptide acylation is a powerful tool to alter the pharmacokinetics, biophysical properties and chemical stability of injectable peptide drugs, primarily used to prolong blood circulation...

  11. Therapeutic use of cannabis.

    Science.gov (United States)

    de Vries, Kay; Green, Anita J

    Therapeutic cannabis use raises a number of dilemmas for nurses. This article examines the legal, political and ethical challenges raised by the use of cannabis by people with life-limiting or terminal illnesses in their own homes. (Throughout this paper, the term cannabis refers to illegal cannabis unless specified.) A literature review of databases from 1996 was conducted and internet material was also examined. Evidence on the therapeutic use of cannabis suggests it may produce improvements in quality of life, which has led to increased use among people with life-limiting illnesses. The cannabis used is usually obtained illegally, which can have consequences for both those who use it and nurses who provide treatment in the community.

  12. Leech Therapeutic Applications

    OpenAIRE

    Abdualkader, A. M.; A M Ghawi; Alaama, M.; M. Awang; A Merzouk

    2013-01-01

    Hematophagous animals including leeches have been known to possess biologically active compounds in their secretions, especially in their saliva. The blood-sucking annelids, leeches have been used for therapeutic purposes since the beginning of civilization. Ancient Egyptian, Indian, Greek and Arab physicians used leeches for a wide range of diseases starting from the conventional use for bleeding to systemic ailments, such as skin diseases, nervous system abnormalities, urinary and reproduct...

  13. Tumor Targeting Using Radiolabeled Antibodies for Image-Guided Drug Delivery.

    Science.gov (United States)

    Rijpkema, Mark; Boerman, Otto C; Oyen, Wim J G

    2015-01-01

    Due to their high target affinity and specificity, antibodies are very suitable tumor-targeting vehicles for imaging and therapeutic application. This enables a theranostic approach of imaging targeted drug delivery in oncology and opens the way for personalized medicine, predicting drug delivery, response, and treatment outcome in the individual patient. Of the currently available molecular imaging techniques, single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are the best suited imaging techniques to visualize and determine drug delivery to the target tissue quantitatively. Using the same antibody for imaging and targeted therapy may eliminate some limitations of antibody-based molecular imaging and therapy, like heterogeneous antigen expression and poor accessibility. However, challenges of this approach remain, for example in the pharmacokinetic behavior of radiolabeled antibodies and antibody-drug-conjugates. Despite these challenges, also exciting opportunities are at the horizon, by using antibodies as multimodal vehicles carrying both a diagnostic agent and a therapeutic agent. In this review, both the challenges and the opportunities of using radiolabeled antibodies for image-guided drug delivery are discussed.

  14. Investigating interactions between phospholipase B-Like 2 and antibodies during Protein A chromatography.

    Science.gov (United States)

    Tran, Benjamin; Grosskopf, Vanessa; Wang, Xiangdan; Yang, Jihong; Walker, Don; Yu, Christopher; McDonald, Paul

    2016-03-18

    Purification processes for therapeutic antibodies typically exploit multiple and orthogonal chromatography steps in order to remove impurities, such as host-cell proteins. While the majority of host-cell proteins are cleared through purification processes, individual host-cell proteins such as Phospholipase B-like 2 (PLBL2) are more challenging to remove and can persist into the final purification pool even after multiple chromatography steps. With packed-bed chromatography runs using host-cell protein ELISAs and mass spectrometry analysis, we demonstrated that different therapeutic antibodies interact to varying degrees with host-cell proteins in general, and PLBL2 specifically. We then used a high-throughput Protein A chromatography method to further examine the interaction between our antibodies and PLBL2. Our results showed that the co-elution of PLBL2 during Protein A chromatography is highly dependent on the individual antibody and PLBL2 concentration in the chromatographic load. Process parameters such as antibody resin load density and pre-elution wash conditions also influence the levels of PLBL2 in the Protein A eluate. Furthermore, using surface plasmon resonance, we demonstrated that there is a preference for PLBL2 to interact with IgG4 subclass antibodies compared to IgG1 antibodies. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Elevated antimeasles antibody titre: An association in autoimmune encephalitis

    Directory of Open Access Journals (Sweden)

    S R Chandra

    2015-01-01

    Full Text Available Introduction: Autoimmune encephalitis is a group of treatable noninfective encephalitic disorders with great clinical implications. They have a close resemblance to prion disease and some slow virus infections. We report the presence of significant titers of antimeasles antibody in some of our patients with autoimmune encephalitis resulting in diagnostic and therapeutic problems. Patients and Methods: Patients seen by us in the last 4 years with high titers (1:625 dilution cerebrospinal fiuid (CSF antimeasles antibody positivity were reviewed retrospectively. The data collected were assessed using SPSS- Statistical Package for Social Sciences Version 15.0 (IBM corporation software. The groups which showed elevated antimeasles antibody titers but did not have other parameters suggestive of subacute sclerosing panencephalitis (Group 2 were segregated and compared with those who had the typical features (Group 1 using Fisher's Exact Test. Results: There were 33 patients with antimeasles antibody in CSF. Group 1 had 27 and Group 2 had 6 patients. Group 1 had lower age, cognitive dysfunction, slow myoclonus, less generalized tonic-clonic seizures, and focal seizures. Group 2 patients belonged to the higher age, had significant psychosis (P = 0.02, incontinence of bowel and bladder (P = 0.0001. Slow myoclonus was significant in the first group (P = 0.028, and weakness was significant in the second group (P = 0.028 and double incontinence in the second group (P = 0.0001. Magnetic resonance imaging showed significant gray matter and cerebellar involvement in Group 2 P = 0.005 and P = 0.028, respectively. Conclusions: Patients who show significant titers of antimeasles antibodies in the CSF but belonging to older age group with psychosis, generalized tonic-clonic seizures, double incontinence, focal myoclonus, and electroencephalographic and imaging noncorroborative need to be investigated for autoimmune encephalitis in view of the great prognostic and

  16. Precipitating antibodies in mycoplasma infection.

    Science.gov (United States)

    Menonna, J; Chmel, H; Menegus, M; Dowling, P; Cook, S

    1977-01-01

    The effectiveness of counterimmunoelectrophoresis (CIEP) for detecting human precipitating antibodies to mcyoplasma antigen was compared with the conventional complement fixation (CF) method in a double-blind experiment. Fifty-one sera from patients suspected of having acute mycoplasma infection were tested by both techniques. Dense precipitin lines to mycoplasma antigen developed in 28 sera with CIEP. Twenty-six of 28 had elevated CF titers to this antigen. No precipitin bands were observed in sera with low antibody titers to mycoplasma. These findings indicate that the CIEP test is a specific method for reliably detecting elevated serum CF antibody levels in patients with acute or recent mycoplasma infection. PMID:328527

  17. Therapeutic advances in the treatment of vasculitis.

    Science.gov (United States)

    Eleftheriou, Despina; Brogan, Paul A

    2016-04-26

    Considerable therapeutic advances for the treatment of vasculitis of the young have been made in the past 10 years, including the development of outcome measures that facilitate clinical trial design. Notably, these include: a recognition that some patients with Kawasaki Disease require corticosteroids as primary treatment combined with IVIG; implementation of rare disease trial design for polyarteritis nodosa to deliver the first randomised controlled trial for children; first clinical trials involving children for anti-neutrophil cytoplasmic antibody (ANCA) vasculitis; and identification of monogenic forms of vasculitis that provide an understanding of pathogenesis, thus facilitating more targeted treatment. Robust randomised controlled trials for Henoch Schönlein Purpura nephritis and Takayasu arteritis are needed; there is also an over-arching need for trials examining new agents that facilitate corticosteroid sparing, of particular importance in the paediatric population since glucocorticoid toxicity is a major concern.

  18. OptMAVEn--a new framework for the de novo design of antibody variable region models targeting specific antigen epitopes.

    Directory of Open Access Journals (Sweden)

    Tong Li

    Full Text Available Antibody-based therapeutics provides novel and efficacious treatments for a number of diseases. Traditional experimental approaches for designing therapeutic antibodies rely on raising antibodies against a target antigen in an immunized animal or directed evolution of antibodies with low affinity for the desired antigen. However, these methods remain time consuming, cannot target a specific epitope and do not lead to broad design principles informing other studies. Computational design methods can overcome some of these limitations by using biophysics models to rationally select antibody parts that maximize affinity for a target antigen epitope. This has been addressed to some extend by OptCDR for the design of complementary determining regions. Here, we extend this earlier contribution by addressing the de novo design of a model of the entire antibody variable region against a given antigen epitope while safeguarding for immunogenicity (Optimal Method for Antibody Variable region Engineering, OptMAVEn. OptMAVEn simulates in silico the in vivo steps of antibody generation and evolution, and is capable of capturing the critical structural features responsible for affinity maturation of antibodies. In addition, a humanization procedure was developed and incorporated into OptMAVEn to minimize the potential immunogenicity of the designed antibody models. As case studies, OptMAVEn was applied to design models of neutralizing antibodies targeting influenza hemagglutinin and HIV gp120. For both HA and gp120, novel computational antibody models with numerous interactions with their target epitopes were generated. The observed rates of mutations and types of amino acid changes during in silico affinity maturation are consistent with what has been observed during in vivo affinity maturation. The results demonstrate that OptMAVEn can efficiently generate diverse computational antibody models with both optimized binding affinity to antigens and reduced

  19. Antibody Production in Plants and Green Algae.

    Science.gov (United States)

    Yusibov, Vidadi; Kushnir, Natasha; Streatfield, Stephen J

    2016-04-29

    Monoclonal antibodies (mAbs) have a wide range of modern applications, including research, diagnostic, therapeutic, and industrial uses. Market demand for mAbs is high and continues to grow. Although mammalian systems, which currently dominate the biomanufacturing industry, produce effective and safe recombinant mAbs, they have a limited manufacturing capacity and high costs. Bacteria, yeast, and insect cell systems are highly scalable and cost effective but vary in their ability to produce appropriate posttranslationally modified mAbs. Plants and green algae are emerging as promising production platforms because of their time and cost efficiencies, scalability, lack of mammalian pathogens, and eukaryotic posttranslational protein modification machinery. So far, plant- and algae-derived mAbs have been produced predominantly as candidate therapeutics for infectious diseases and cancer. These candidates have been extensively evaluated in animal models, and some have shown efficacy in clinical trials. Here, we review ongoing efforts to advance the production of mAbs in plants and algae.

  20. Plant-produced anti-dengue virus monoclonal antibodies exhibit reduced antibody-dependent enhancement of infection activity.

    Science.gov (United States)

    Dent, Matthew; Hurtado, Jonathan; Paul, Amber M; Sun, Haiyan; Lai, Huafang; Yang, Ming; Esqueda, Adrian; Bai, Fengwei; Steinkellner, Herta; Chen, Qiang

    2016-12-01

    The mAb E60 has the potential to be a desirable therapeutic molecule since it efficiently neutralizes all four serotypes of dengue virus (DENV). However, mammalian-cell-produced E60 exhibits antibody-dependent enhancement of infection (ADE) activity, rendering it inefficacious in vivo, and treated animals more susceptible to developing more severe diseases during secondary infection. In this study, we evaluated a plant-based expression system for the production of therapeutically suitable E60. The mAb was transiently expressed in Nicotiana benthamianaWT and a ∆XFT line, a glycosylation mutant lacking plant-specific N-glycan residues. The mAb was efficiently expressed and assembled in leaves and exhibited highly homogenous N-glycosylation profiles, i.e. GnGnXF3 or GnGn structures, depending on the expression host. Both E60 glycovariants demonstrated equivalent antigen-binding specificity and in vitro neutralization potency against DENV serotypes 2 and 4 compared with their mammalian-cell-produced counterpart. By contrast, plant-produced E60 exhibited reduced ADE activity in Fc gamma receptor expressing human cells. Our results suggest the ability of plant-produced antibodies to minimize ADE, which may lead to the development of safe and highly efficacious antibody-based therapeutics against DENV and other ADE-prone viral diseases. Our study provides so far unknown insight into the relationship between mAb N-glycosylation and ADE, which contributes to our understanding of how sugar moieties of antibodies modulate Fc-mediated functions and viral pathogenesis.

  1. Analysis of monoclonal antibodies by sedimentation velocity analytical ultracentrifugation.

    Science.gov (United States)

    Stine, W Blaine

    2013-01-01

    Development of a thorough understanding of the solution polydispersity of therapeutic glycoproteins including monoclonal antibodies is an important and challenging undertaking. Degradation pathways involving fragmentation could result in loss of therapeutic efficacy. Protein aggregation on the other hand is frequently considered a critical quality attribute, and concerns exist that protein aggregates could result in undesirable immunological consequences (1). Sedimentation velocity analysis performed in the analytical ultracentrifuge (SV-AUC) provides a uniquely powerful first principal measure of the hydrodynamic size and shape of proteins under conditions that can come very close to the formulated drug product. This technique avoids the potential pitfalls associated with size exclusion chromatography (SEC) including on-column dilution, adsorption or disruption of species by a stationary phase, and the need to use high ionic strength mobile phases to screen unwanted electrostatic interactions (2, 3). Furthermore, not only does SV-AUC provide a quantitative size distribution analysis, but it also provides information about macromolecular conformation. For these reasons, use of SV-AUC for analysis of therapeutic monoclonal antibodies has become widespread throughout the biopharmaceutical industry and is one of the most common orthogonal techniques to SEC for measuring aggregate and fragment levels (4-9). The studies outlined in this chapter describe the basic principles of designing, collecting, and analyzing experimental data using SV-AUC with a focus on methods for therapeutic monoclonal antibodies and other similar biologics. Details are given that facilitate the acquisition of high quality data sets that in turn simplify data analysis resulting in robust and accurate measures of solution polydispersity.

  2. What Is Antiphospholipid Antibody Syndrome?

    Science.gov (United States)

    ... specialize in treating these types of disorders. Medical History Some people have APS antibodies but no signs ... warfarin starts to work, the heparin is stopped. Aspirin also thins the blood and helps prevent blood ...

  3. Antisperm antibodies and fertility association.

    Science.gov (United States)

    Restrepo, B; Cardona-Maya, W

    2013-10-01

    To evaluate the relation between antisperm antibodies (ASA) and human fertility by reviewing the scientific literature of the last 45 years. We carried out a review of scientific literature about antisperm antibodies and infertility published in spanish or english in databases as Pubmed, Medline, Scielo, some books and another gray literature include information related to this review and that is published in the last 45 years. Infertile couples suffer infertility by immunological mechanisms mainly by the presence of antisperm antibodies ASA in blood, semen or cervicovaginal secretions; the formation of ASA in men and women may be associated with disturbance in immunomodulatory mechanisms that result in functional impairment of sperm and thus its inability to fertilize the oocyte. Immunological infertility caused by ASA is the result of interference of these antibodies in various stages of fertilization process, inhibiting the ability of interaction between sperm and oocyte. Copyright © 2012 AEU. Published by Elsevier Espana. All rights reserved.

  4. Development of antibody-based c-Met inhibitors for targeted cancer therapy

    Directory of Open Access Journals (Sweden)

    Lee D

    2015-02-01

    Full Text Available Dongheon Lee, Eun-Sil Sung, Jin-Hyung Ahn, Sungwon An, Jiwon Huh, Weon-Kyoo You Hanwha Chemical R&D Center, Biologics Business Unit, Daejeon, Republic of Korea Abstract: Signaling pathways mediated by receptor tyrosine kinases (RTKs and their ligands play important roles in the development and progression of human cancers, which makes RTK-mediated signaling pathways promising therapeutic targets in the treatment of cancer. Compared with small-molecule compounds, antibody-based therapeutics can more specifically recognize and bind to ligands and RTKs. Several antibody inhibitors of RTK-mediated signaling pathways, such as human epidermal growth factor receptor 2, vascular endothelial growth factor, epidermal growth factor receptor or vascular endothelial growth factor receptor 2, have been developed and are widely used to treat cancer patients. However, since the therapeutic options are still limited in terms of therapeutic efficacy and types of cancers that can be treated, efforts are being made to identify and evaluate novel RTK-mediated signaling pathways as targets for more efficacious cancer treatment. The hepatocyte growth factor/c-Met signaling pathway has come into the spotlight as a promising target for development of potent cancer therapeutic agents. Multiple antibody-based therapeutics targeting hepatocyte growth factor or c-Met are currently in preclinical or clinical development. This review focuses on the development of inhibitors of the hepatocyte growth factor/c-Met signaling pathway for cancer treatment, including critical issues in clinical development and future perspectives for antibody-based therapeutics. Keywords: hepatocyte growth factor, ligands, receptor tyrosine kinase, signaling pathway, therapeutic agent

  5. Monoclonal antibody aggregates: physicochemical characteristics, stability in biological fluids and immunogenicity

    OpenAIRE

    Filipe, V.L.S.

    2012-01-01

    Therapeutic proteins have become invaluable in treating a wide range of serious and life-threatening diseases. However, repeated administration of these drugs to patients often induces the formation of undesirable anti-drug antibodies, also known as immunogenicity. Among the factors that are known to play a role in immunogenicity of therapeutic proteins, the presence of protein aggregates has been indicated as one of the main product-related risk factors. Even though several studies have show...

  6. Fragmentation of monoclonal antibodies

    Science.gov (United States)

    Vlasak, Josef

    2011-01-01

    Fragmentation is a degradation pathway ubiquitously observed in proteins despite the remarkable stability of peptide bond; proteins differ only by how much and where cleavage occurs. The goal of this review is to summarize reports regarding the non-enzymatic fragmentation of the peptide backbone of monoclonal antibodies (mAbs). The sites in the polypeptide chain susceptible to fragmentation are determined by a multitude of factors. Insights are provided on the intimate chemical mechanisms that can make some bonds prone to cleavage due to the presence of specific side-chains. In addition to primary structure, the secondary, tertiary and quaternary structures have a significant impact in modulating the distribution of cleavage sites by altering local flexibility, accessibility to solvent or bringing in close proximity side chains that are remote in sequence. This review focuses on cleavage sites observed in the constant regions of mAbs, with special emphasis on hinge fragmentation. The mechanisms responsible for backbone cleavage are strongly dependent on pH and can be catalyzed by metals or radicals. The distribution of cleavage sites are different under acidic compared to basic conditions, with fragmentation rates exhibiting a minimum in the pH range 5–6; therefore, the overall fragmentation pattern observed for a mAb is a complex result of structural and solvent conditions. A critical review of the techniques used to monitor fragmentation is also presented; usually a compromise has to be made between a highly sensitive method with good fragment separation and the capability to identify the cleavage site. The effect of fragmentation on the function of a mAb must be evaluated on a case-by-case basis depending on whether cleavage sites are observed in the variable or constant regions, and on the mechanism of action of the molecule. PMID:21487244

  7. Frankincense--therapeutic properties.

    Science.gov (United States)

    Al-Yasiry, Ali Ridha Mustafa; Kiczorowska, Bożena

    2016-01-04

    Recently, increasing interest in natural dietary and therapeutic preparations used as dietary supplements has been observed. One of them is frankincense. This traditional medicine of the East is believed to have anti-inflammatory, expectorant, antiseptic, and even anxiolytic and anti-neurotic effects. The present study aims to verify the reported therapeutic properties of Boswellia resin and describe its chemical composition based on available scientific studies. The main component of frankincense is oil (60%). It contains mono- (13%) and diterpenes (40%) as well as ethyl acetate (21.4%), octyl acetate (13.4%) and methylanisole (7.6%). The highest biological activity among terpenes is characteristic of 11-keto-ß-acetyl-beta-boswellic acid, acetyl-11-keto-ß-boswellic acid and acetyl-α-boswellic acid. Contemporary studies have shown that resin indeed has an analgesic, tranquilising and anti-bacterial effects. From the point of view of therapeutic properties, extracts from Boswellia serrata and Boswellia carterii are reported to be particularly useful. They reduce inflammatory conditions in the course of rheumatism by inhibiting leukocyte elastase and degrading glycosaminoglycans. Boswellia preparations inhibit 5-lipoxygenase and prevent the release of leukotrienes, thus having an anti-inflammatory effect in ulcerative colitis, irritable bowel syndrome, bronchitis and sinusitis. Inhalation and consumption of Boswellia olibanum reduces the risk of asthma. In addition, boswellic acids have an antiproliferative effect on tumours. They inhibit proliferation of tumour cells of the leukaemia and glioblastoma subset. They have an anti-tumour effect since they inhibit topoisomerase I and II-alpha and stimulate programmed cell death (apoptosis).

  8. Frankincense – therapeutic properties

    Directory of Open Access Journals (Sweden)

    Ali Ridha Mustafa Al-Yasiry

    2016-01-01

    Full Text Available Recently, increasing interest in natural dietary and therapeutic preparations used as dietary supplements has been observed. One of them is frankincense. This traditional medicine of the East is believed to have anti-inflammatory, expectorant, antiseptic, and even anxiolytic and anti-neurotic effects. The present study aims to verify the reported therapeutic properties of Boswellia resin and describe its chemical composition based on available scientific studies. The main component of frankincense is oil (60%. It contains mono- (13% and diterpenes (40% as well as ethyl acetate (21.4%, octyl acetate (13.4% and methylanisole (7.6%. The highest biological activity among terpenes is characteristic of 11-keto-ß-acetyl-beta-boswellic acid, acetyl-11-keto-ß-boswellic acid and acetyl-α-boswellic acid. Contemporary studies have shown that resin indeed has an analgesic, tranquilising and anti-bacterial effects. From the point of view of therapeutic properties, extracts from Boswellia serrata and Boswellia carterii are reported to be particularly useful. They reduce inflammatory conditions in the course of rheumatism by inhibiting leukocyte elastase and degrading glycosaminoglycans. Boswellia preparations inhibit 5-lipoxygenase and prevent the release of leukotrienes, thus having an anti-inflammatory effect in ulcerative colitis, irritable bowel syndrome, bronchitis and sinusitis. Inhalation and consumption of Boswellia olibanum reduces the risk of asthma. In addition, boswellic acids have an antiproliferative effect on tumours. They inhibit proliferation of tumour cells of the leukaemia and glioblastoma subset. They have an anti-tumour effect since they inhibit topoisomerase I and II-alpha and stimulate programmed cell death (apoptosis.

  9. [Therapeutic applications of digestive endoscopy].

    Science.gov (United States)

    Ortega, J A; Pérez, L; Madureri, V

    1976-01-01

    Endoscopy has proven useful as a diagnostic tool and recently many useful therapeutic possibilities have been proposed. The authors discuss their experience with therapeutic endoscopic procedures and present new ones for treatment of Acalasia and small sliding hiatal hernia.

  10. Therapeutic approaches to cellulite.

    Science.gov (United States)

    Green, Jeremy B; Cohen, Joel L; Kaufman, Joely; Metelitsa, Andrei I; Kaminer, Michael S

    2015-09-01

    Cellulite is a condition that affects the vast majority of women. Although it is of no danger to one's overall health, cellulite can be psychosocially debilitating. Consequently, much research has been devoted to understanding cellulite and its etiopathogenesis. With additional insights into the underlying causes of its clinical presentation, therapeutic modalities have been developed that offer hope to cellulite sufferers. This review examines evidence for topical treatments, noninvasive energy-based devices, and recently developed minimally invasive interventions that may finally provide a solution. ©2015 Frontline Medical Communications.

  11. [Achievement of therapeutic objectives].

    Science.gov (United States)

    Mantilla, Teresa

    2014-07-01

    Therapeutic objectives for patients with atherogenic dyslipidemia are achieved by improving patient compliance and adherence. Clinical practice guidelines address the importance of treatment compliance for achieving objectives. The combination of a fixed dose of pravastatin and fenofibrate increases the adherence by simplifying the drug regimen and reducing the number of daily doses. The good tolerance, the cost of the combination and the possibility of adjusting the administration to the patient's lifestyle helps achieve the objectives for these patients with high cardiovascular risk. Copyright © 2014 Sociedad Española de Arteriosclerosis y Elsevier España, S.L. All rights reserved.

  12. [Is therapeutic deadlock inevitable?].

    Science.gov (United States)

    Vignat, Jean-Pierre

    2016-01-01

    Many long-term treatments appear to be an expression of therapeutic deadlock. The situation leads to a questioning of the concept of chronicity and the identification of the determining factors of situations which are apparently blocked, marked by the search for solutions taking a back seat to the taking of action. The interaction between patients' mental apparatus and the care apparatus lies at the heart of the question, interpreted from an institutional, collective and individual perspective, supported by the clinical and psychopathological approach, and the return to the prioritisation of the thought. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Tabhu: tools for antibody humanization.

    KAUST Repository

    Olimpieri, Pier Paolo

    2014-10-09

    SUMMARY: Antibodies are rapidly becoming essential tools in the clinical practice, given their ability to recognize their cognate antigens with high specificity and affinity, and a high yield at reasonable costs in model animals. Unfortunately, when administered to human patients, xenogeneic antibodies can elicit unwanted and dangerous immunogenic responses. Antibody humanization methods are designed to produce molecules with a better safety profile still maintaining their ability to bind the antigen. This can be accomplished by grafting the non-human regions determining the antigen specificity into a suitable human template. Unfortunately, this procedure may results in a partial or complete loss of affinity of the grafted molecule that can be restored by back-mutating some of the residues of human origin to the corresponding murine ones. This trial-and-error procedure is hard and involves expensive and time-consuming experiments. Here we present tools for antibody humanization (Tabhu) a web server for antibody humanization. Tabhu includes tools for human template selection, grafting, back-mutation evaluation, antibody modelling and structural analysis, helping the user in all the critical steps of the humanization experiment protocol. AVAILABILITY: http://www.biocomputing.it/tabhu CONTACT: anna.tramontano@uniroma1.it, pierpaolo.olimpieri@uniroma1.it SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

  14. Tabhu: tools for antibody humanization.

    Science.gov (United States)

    Olimpieri, Pier Paolo; Marcatili, Paolo; Tramontano, Anna

    2015-02-01

    Antibodies are rapidly becoming essential tools in the clinical practice, given their ability to recognize their cognate antigens with high specificity and affinity, and a high yield at reasonable costs in model animals. Unfortunately, when administered to human patients, xenogeneic antibodies can elicit unwanted and dangerous immunogenic responses. Antibody humanization methods are designed to produce molecules with a better safety profile still maintaining their ability to bind the antigen. This can be accomplished by grafting the non-human regions determining the antigen specificity into a suitable human template. Unfortunately, this procedure may results in a partial or complete loss of affinity of the grafted molecule that can be restored by back-mutating some of the residues of human origin to the corresponding murine ones. This trial-and-error procedure is hard and involves expensive and time-consuming experiments. Here we present tools for antibody humanization (Tabhu) a web server for antibody humanization. Tabhu includes tools for human template selection, grafting, back-mutation evaluation, antibody modelling and structural analysis, helping the user in all the critical steps of the humanization experiment protocol. http://www.biocomputing.it/tabhu anna.tramontano@uniroma1.it, pierpaolo.olimpieri@uniroma1.it Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

  15. Neutralising Antibodies against Ricin Toxin

    Science.gov (United States)

    Prigent, Julie; Panigai, Laetitia; Lamourette, Patricia; Sauvaire, Didier; Devilliers, Karine; Plaisance, Marc; Volland, Hervé; Créminon, Christophe; Simon, Stéphanie

    2011-01-01

    The Centers for Disease Control and Prevention have listed the potential bioweapon ricin as a Category B Agent. Ricin is a so-called A/B toxin produced by plants and is one of the deadliest molecules known. It is easy to prepare and no curative treatment is available. An immunotherapeutic approach could be of interest to attenuate or neutralise the effects of the toxin. We sought to characterise neutralising monoclonal antibodies against ricin and to develop an effective therapy. For this purpose, mouse monoclonal antibodies (mAbs) were produced against the two chains of ricin toxin (RTA and RTB). Seven mAbs were selected for their capacity to neutralise the cytotoxic effects of ricin in vitro. Three of these, two anti-RTB (RB34 and RB37) and one anti-RTA (RA36), when used in combination improved neutralising capacity in vitro with an IC50 of 31 ng/ml. Passive administration of association of these three mixed mAbs (4.7 µg) protected mice from intranasal challenges with ricin (5 LD50). Among those three antibodies, anti-RTB antibodies protected mice more efficiently than the anti-RTA antibody. The combination of the three antibodies protected mice up to 7.5 hours after ricin challenge. The strong in vivo neutralising capacity of this three mAbs combination makes it potentially useful for immunotherapeutic purposes in the case of ricin poisoning or possibly for prevention. PMID:21633505

  16. Neutralising antibodies against ricin toxin.

    Directory of Open Access Journals (Sweden)

    Julie Prigent

    Full Text Available The Centers for Disease Control and Prevention have listed the potential bioweapon ricin as a Category B Agent. Ricin is a so-called A/B toxin produced by plants and is one of the deadliest molecules known. It is easy to prepare and no curative treatment is available. An immunotherapeutic approach could be of interest to attenuate or neutralise the effects of the toxin. We sought to characterise neutralising monoclonal antibodies against ricin and to develop an effective therapy. For this purpose, mouse monoclonal antibodies (mAbs were produced against the two chains of ricin toxin (RTA and RTB. Seven mAbs were selected for their capacity to neutralise the cytotoxic effects of ricin in vitro. Three of these, two anti-RTB (RB34 and RB37 and one anti-RTA (RA36, when used in combination improved neutralising capacity in vitro with an IC(50 of 31 ng/ml. Passive administration of association of these three mixed mAbs (4.7 µg protected mice from intranasal challenges with ricin (5 LD(50. Among those three antibodies, anti-RTB antibodies protected mice more efficiently than the anti-RTA antibody. The combination of the three antibodies protected mice up to 7.5 hours after ricin challenge. The strong in vivo neutralising capacity of this three mAbs combination makes it potentially useful for immunotherapeutic purposes in the case of ricin poisoning or possibly for prevention.

  17. Single-domain antibody-based and linker-free bispecific antibodies targeting FcγRIII induce potent antitumor activity without recruiting regulatory T cells.

    Science.gov (United States)

    Rozan, Caroline; Cornillon, Amélie; Pétiard, Corinne; Chartier, Martine; Behar, Ghislaine; Boix, Charlotte; Kerfelec, Brigitte; Robert, Bruno; Pèlegrin, André; Chames, Patrick; Teillaud, Jean-Luc; Baty, Daniel

    2013-08-01

    Antibody-dependent cell-mediated cytotoxicity, one of the most prominent modes of action of antitumor antibodies, suffers from important limitations due to the need for optimal interactions with Fcγ receptors. In this work, we report the design of a new bispecific antibody format, compact and linker-free, based on the use of llama single-domain antibodies that are capable of circumventing most of these limitations. This bispecific antibody format was created by fusing single-domain antibodies directed against the carcinoembryonic antigen and the activating FcγRIIIa receptor to human Cκ and CH1 immunoglobulin G1 domains, acting as a natural dimerization motif. In vitro and in vivo characterization of these Fab-like bispecific molecules revealed favorable features for further development as a therapeutic molecule. They are easy to produce in Escherichia coli, very stable, and elicit potent lysis of tumor cells by human natural killer cells at picomolar concentrations. Unlike conventional antibodies, they do not engage inhibitory FcγRIIb receptor, do not compete with serum immunoglobulins G for receptor binding, and their cytotoxic activity is independent of Fc glycosylation and FcγRIIIa polymorphism. As opposed to anti-CD3 bispecific antitumor antibodies, they do not engage regulatory T cells as these latter cells do not express FcγRIII. Studies in nonobese diabetic/severe combined immunodeficient gamma mice xenografted with carcinoembryonic antigen-positive tumor cells showed that Fab-like bispecific molecules in the presence of human peripheral blood mononuclear cells significantly slow down tumor growth. This new compact, linker-free bispecific antibody format offers a promising approach for optimizing antibody-based therapies.

  18. Production of secretory IgA antibodies in plants.

    Science.gov (United States)

    Larrick, J W; Yu, L; Naftzger, C; Jaiswal, S; Wycoff, K

    2001-10-15

    Functional antibodies produced in tobacco plants were first reported over a decade ago (1989). The basic protocol used to generate these 'plantibodies' involved the independent cloning of H and L chain antibody genes in Agrobacterium tumefaciens vectors, the transformation of plant tissue in vitro with the recombinant bacterium, the reconstitution of whole plants expressing individual chains, and their sexual cross. In a 'Mendelian' fashion, a fully assembled and functional antibody was recovered from plant tissue in some double-transgenic plants. In mammalian cells, the antibody H and L chains are produced as precursor proteins that are translocated into the endoplasmic reticulum (ER), under the guidance of signal sequences. Within the ER, the signal peptides are proteolytically cleaved, and several stress proteins act as chaperonins to bind the unassembled antibody chains, and direct subsequent folding and tetramer formation. A similar process occurs in plant cells, and expression can be directed via signal sequences (even of foreign origin) into the aqueous environment of the apoplasm, or to be accumulated in other specific plant tissues, including tubers, fruit, or seed. Plants can facilely assemble secretory IgA, which is comprised of four chains, H and L chains, J chain and secretory component. Plant 'bioreactors' are expected to yield over 10 kg of therapeutic antibody/acre in tobacco, maize, soybean, and alfalfa [(Ann. NY Acad. Sci.)721(1994)235; (Biotechnol. Bioeng.)20(1999)135]. Compared with conventional steel tank bioreactors using mammalian cells, or microorganisms, the costs of GMP plantibodies are expected to perhaps one tenth. The differences in glycosylation patterns of plant and mammalian cell produced antibodies apparently have no effect on antigen-binding or specificity, but there is some concern about potential immunogenicity in humans. N-linked glycans of plants differ from human by having fucose-linked alpha 1,3 and the sugar xylose. No

  19. Recent developments in therapeutic protein expression technologies in plants.

    Science.gov (United States)

    Fahad, Shah; Khan, Faheem Ahmed; Pandupuspitasari, Nuruliarizki Shinta; Ahmed, Muhammad Mahmood; Liao, Yu Cai; Waheed, Muhammad Tahir; Sameeullah, Muhammad; Darkhshan; Hussain, Saddam; Saud, Shah; Hassan, Shah; Jan, Amanullah; Jan, Mohammad Tariq; Wu, Chao; Chun, Ma Xiao; Huang, Jianliang

    2015-02-01

    Infectious diseases and cancers are some of the commonest causes of deaths throughout the world. The previous two decades have witnessed a combined endeavor across various biological sciences to address this issue in novel ways. The advent of recombinant DNA technologies has provided the tools for producing recombinant proteins that can be used as therapeutic agents. A number of expression systems have been developed for the production of pharmaceutical products. Recently, advances have been made using plants as bioreactors to produce therapeutic proteins directed against infectious diseases and cancers. This review highlights the recent progress in therapeutic protein expression in plants (stable and transient), the factors affecting heterologous protein expression, vector systems and recent developments in existing technologies and steps towards the industrial production of plant-made vaccines, antibodies, and biopharmaceuticals.

  20. Developments in therapy with monoclonal antibodies and related proteins.

    Science.gov (United States)

    Shepard, H Michael; Phillips, Gail Lewis; D Thanos, Christopher; Feldmann, Marc

    2017-06-01

    Monoclonal antibody therapeutics have been approved for over 30 targets and diseases, most commonly cancer. Antibodies have become the new backbone of the pharmaceutical industry, which previously relied on small molecules. Compared with small molecules, monoclonal antibodies (mAbs) have exquisite target selectivity and hence less toxicity as a result of binding other targets. The clinical value of both mAbs and ligand traps has been proven. New applications of mAbs are being tested and mAbs have now been designed to target two (bi-specific, eg TNF-α and IL-17) or more targets simultaneously, augmenting their therapeutic potential. Because of space limitations and the wide ranging scope of this review there are regrettably, but inevitably, omissions and missing citations. We have chosen to highlight the first successes in inflammatory diseases and cancer, but a broader overview of approved mAbs and related molecules can be found in Table 1. © Royal College of Physicians 2017. All rights reserved.

  1. Plant Factories for the Production of Monoclonal Antibodies.

    Science.gov (United States)

    Sheshukova, E V; Komarova, T V; Dorokhov, Y L

    2016-10-01

    Like animal cells, plant cells bear mechanisms for protein synthesis and posttranslational modification (glycosylation and phosphorylation) that allow them to be seriously considered as factories for therapeutic proteins, including antibodies, with the development of biotechnology. The plant platform for monoclonal antibody production is an attractive approach due to its flexibility, speed, scalability, low cost of production, and lack of contamination risk from animal-derived pathogens. Contemporary production approaches for therapeutic proteins rely on transgenic plants that are obtained via the stable transformation of plant cells as well as the transient (temporary) expression of foreign proteins. In this review, we discuss present-day approaches for monoclonal antibody production in plants (MAPP), features of carbohydrate composition, and methods for the humanization of the MAPP carbohydrate profile. MAPPs that have successfully passed preclinical studies and may be promising for use in clinical practice are presented here. Perspectives on using MAPPs are determined by analyzing their economic benefits and production rates, which are especially important in personalized cancer therapy as well as in cases of bioterrorism and pandemics.

  2. Antibody humanization by structure-based computational protein design.

    Science.gov (United States)

    Choi, Yoonjoo; Hua, Casey; Sentman, Charles L; Ackerman, Margaret E; Bailey-Kellogg, Chris

    2015-01-01

    Antibodies derived from non-human sources must be modified for therapeutic use so as to mitigate undesirable immune responses. While complementarity-determining region (CDR) grafting-based humanization techniques have been successfully applied in many cases, it remains challenging to maintain the desired stability and antigen binding affinity upon grafting. We developed an alternative humanization approach called CoDAH ("Computationally-Driven Antibody Humanization") in which computational protein design methods directly select sets of amino acids to incorporate from human germline sequences to increase humanness while maintaining structural stability. Retrospective studies show that CoDAH is able to identify variants deemed beneficial according to both humanness and structural stability criteria, even for targets lacking crystal structures. Prospective application to TZ47, a murine anti-human B7H6 antibody, demonstrates the approach. Four diverse humanized variants were designed, and all possible unique VH/VL combinations were produced as full-length IgG1 antibodies. Soluble and cell surface expressed antigen binding assays showed that 75% (6 of 8) of the computationally designed VH/VL variants were successfully expressed and competed with the murine TZ47 for binding to B7H6 antigen. Furthermore, 4 of the 6 bound with an estimated KD within an order of magnitude of the original TZ47 antibody. In contrast, a traditional CDR-grafted variant could not be expressed. These results suggest that the computational protein design approach described here can be used to efficiently generate functional humanized antibodies and provide humanized templates for further affinity maturation.

  3. Female Infertility and Serum Auto-antibodies: a Systematic Review.

    Science.gov (United States)

    Deroux, Alban; Dumestre-Perard, Chantal; Dunand-Faure, Camille; Bouillet, Laurence; Hoffmann, Pascale

    2017-08-01

    On average, 10 % of infertile couples have unexplained infertility. Auto-immune disease (systemic lupus erythematosus, anti-phospholipid syndrome) accounts for a part of these cases. In the last 20 years, aspecific auto-immunity, defined as positivity of auto-antibodies in blood sample without clinical or biological criteria for defined diseases, has been evoked in a subpopulation of infertile women. A systematic review was performed (PUBMED) using the MESH search terms "infertility" and "auto-immunity" or "reproductive technique" or "assisted reproduction" or "in vitro fertilization" and "auto-immunity." We retained clinical and physiopathological studies that were applicable to the clinician in assuming joint management of both infertility associated with serum auto-antibodies in women. Thyroid auto-immunity which affects thyroid function could be a cause of infertility; even in euthyroidia, the presence of anti-thyroperoxydase antibodies and/or thyroglobulin are related to infertility. The presence of anti-phospholipid (APL) and/or anti-nuclear (ANA) antibodies seems to be more frequent in the population of infertile women; serum auto-antibodies are associated with early ovarian failure, itself responsible for fertility disorders. However, there exist few publications on this topic. The methods of dosage, as well as the clinical criteria of unexplained infertility deserve to be standardized to allow a precise response to the question of the role of serum auto-antibodies in these women. The direct pathogenesis of this auto-immunity is unknown, but therapeutic immunomodulators, prescribed on a case-by-case basis, could favor pregnancy even in cases of unexplained primary or secondary infertility.

  4. BRCAA1 antibody- and Her2 antibody-conjugated amphiphilic polymer engineered CdSe/ZnS quantum dots for targeted imaging of gastric cancer

    Science.gov (United States)

    Li, Chao; Ji, Yang; Wang, Can; Liang, Shujing; Pan, Fei; Zhang, Chunlei; Chen, Feng; Fu, Hualin; Wang, Kan; Cui, Daxiang

    2014-05-01

    Successful development of safe and highly effective nanoprobes for targeted imaging of in vivo early gastric cancer is a great challenge. Herein, we choose the CdSe/ZnS (core-shell) quantum dots (QDs) as prototypical materials, synthesized one kind of a new amphiphilic polymer including dentate-like alkyl chains and multiple carboxyl groups, and then used the prepared amphiphilic polymer to modify QDs. The resultant amphiphilic polymer engineered QDs (PQDs) were conjugated with BRCAA1 and Her2 monoclonal antibody, and prepared BRCAA1 antibody- and Her2 antibody-conjugated QDs were used for in vitro MGC803 cell labeling and in vivo targeted imaging of gastric cancer cells. Results showed that the PQDs exhibited good water solubility, strong photoluminescence (PL) intensity, and good biocompatibility. BRCAA1 antibody- and Her2 antibody-conjugated QD nanoprobes successfully realized targeted imaging of in vivo gastric cancer MGC803 cells. In conclusion, BRCAA1 antibody- and Her2 antibody-conjugated PQDs have great potential in applications such as single cell labeling and in vivo tracking, and targeted imaging and therapeutic effects' evaluation of in vivo early gastric cancer cells in the near future.

  5. NEUROSYPHILIS IN THERAPEUTIC PRACTICE: CLINICAL OBSERVATION

    Directory of Open Access Journals (Sweden)

    N. A. Shostak

    2017-01-01

    Full Text Available Objective: to describe a clinical case of neurosyphilis diagnosed in a therapeutic inpatient facility.Materials and methods. Female patient T., 61, was hospitalized in the therapeutic department of a general hospital with referral diagnosis of “Stage II hypertensive heart disease, risk 4. Hypertensive crisis of 03.12.2015” with complaints of general fatigue, episodes of transient memory loss with full recovery, unstable blood pressure level. The patient was examined: She underwent treponemal and nontreponemal serological tests for antibodies against Treponema рallidum, hepatitis, human immunodeficiency virus; electrocardiogram; angiography of carotid and vertebral arteries; magnetic resonance imaging (MRI  of the brain with contrast; serological and microscopic examinations of the cerebrospinal fluid (CSF.Results. The patient»s medical history described episodes of transient global amnesia with full memory recovery, more frequent in the last year; arterial hypertension; chronic urinary tract infection; and chronic cholecystitis with frequent courses of antibacterial therapy (ceftriaxone. Since 1986, a positive serological reaction for syphilis was observed (Wassermann reaction (WR +++ due to a history of primary syphilis. Considering reliable history of syphilis, positive serum confirmation tests for syphilis (nontreponemal: rapid plasma reagin test 3+; treponemal: passive hemagglutination reaction 4+, antibodies against T. pallidum (total – present, history of neuropsychological symptoms (transient amnesia and acute neurological symptoms before hospitalization (transient ischemic attack, brain MRI data (2 lesions of cerebral circulation disorders of ischemic type in the cortical branches of left and right mesencephalic arteries, a diagnosis of neurosyphilis was proposed, and lumbar puncture was performed for confirmation. Inflammatory characteristics of the CSF (cytosis 19/3, neutrophilia up to 12 cells, insignificant lymphocytosis up

  6. Mechanisms of Plasma Therapeutics

    Science.gov (United States)

    Graves, David

    2015-09-01

    In this talk, I address research directed towards biomedical applications of atmospheric pressure plasma such as sterilization, surgery, wound healing and anti-cancer therapy. The field has seen remarkable growth in the last 3-5 years, but the mechanisms responsible for the biomedical effects have remained mysterious. It is known that plasmas readily create reactive oxygen species (ROS) and reactive nitrogen species (RNS). ROS and RNS (or RONS), in addition to a suite of other radical and non-radical reactive species, are essential actors in an important sub-field of aerobic biology termed ``redox'' (or oxidation-reduction) biology. It is postulated that cold atmospheric plasma (CAP) can trigger a therapeutic shielding response in tissue in part by creating a time- and space-localized, burst-like form of oxy-nitrosative stress on near-surface exposed cells through the flux of plasma-generated RONS. RONS-exposed surface layers of cells communicate to the deeper levels of tissue via a form of the ``bystander effect,'' similar to responses to other forms of cell stress. In this proposed model of CAP therapeutics, the plasma stimulates a cellular survival mechanism through which aerobic organisms shield themselves from infection and other challenges.

  7. Therapeutic Uses of Exosomes

    Directory of Open Access Journals (Sweden)

    Zacharias E. Suntres

    2013-01-01

    Full Text Available Exosomes are membrane vesicles with a diameter of 40–100 nm that are secreted by many cell types into the extracellular milieu. Exosomes are found in cell culture supernatants and in different biological fluids and are known to be secreted by most cell types under normal and pathological conditions. Considerable research is focusing on the exploitation of exosomes in biological fluids for biomarkers in the diagnosis of disease. More recently, exosomes are being exploited for their therapeutic potential. Exosomes derived from dendritic cells, tumor cells, and malignant effusions demonstrate immunomodulatory functions and are able to present antigens to T-cells and stimulate antigen-specific T-cell responses. Exosomes have also been examined for their therapeutic potential in the treatment of infections such as toxoplasmosis, diphtheria, tuberculosis and atypical severe acute respiratory syndrome as well as autoimmune diseases. Attempts to find practical applications for exosomes continue to expand with the role of exosomes as a drug delivery system for the treatment of autoimmune/inflammatory diseases and cancers.

  8. Engineering therapeutic protein disaggregases.

    Science.gov (United States)

    Shorter, James

    2016-05-15

    Therapeutic agents are urgently required to cure several common and fatal neurodegenerative disorders caused by protein misfolding and aggregation, including amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), and Alzheimer's disease (AD). Protein disaggregases that reverse protein misfolding and restore proteins to native structure, function, and localization could mitigate neurodegeneration by simultaneously reversing 1) any toxic gain of function of the misfolded form and 2) any loss of function due to misfolding. Potentiated variants of Hsp104, a hexameric AAA+ ATPase and protein disaggregase from yeast, have been engineered to robustly disaggregate misfolded proteins connected with ALS (e.g., TDP-43 and FUS) and PD (e.g., α-synuclein). However, Hsp104 has no metazoan homologue. Metazoa possess protein disaggregase systems distinct from Hsp104, including Hsp110, Hsp70, and Hsp40, as well as HtrA1, which might be harnessed to reverse deleterious protein misfolding. Nevertheless, vicissitudes of aging, environment, or genetics conspire to negate these disaggregase systems in neurodegenerative disease. Thus, engineering potentiated human protein disaggregases or isolating small-molecule enhancers of their activity could yield transformative therapeutics for ALS, PD, and AD. © 2016 Shorter. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  9. Hyperthermia Using Antibody-Conjugated Magnetic Nanoparticles and Its Enhanced Effect with Cryptotanshinone

    Directory of Open Access Journals (Sweden)

    Satoshi Ota

    2014-04-01

    Full Text Available Heat dissipation by magnetic nanoparticles (MNPs under an alternating magnetic field can be used to selectively treat cancer tissues. Antibodies conjugated to MNPs can enhance the therapeutic effects of hyperthermia by altering antibody-antigen interactions. Fe3O4 nanoparticles (primary diameter, 20–30 nm coated with polyethylenimine (PEI were prepared and conjugated with CH11, an anti-Fas monoclonal antibody. HeLa cell growth was then evaluated as a function of antibody and MNP/antibody complex doses. HeLa cell growth decreased with increased doses of the antibody and complexes. However, MNPs alone did not affect cell growth; thus, only the antibody affected cell growth. In hyperthermia experiments conducted using an alternating magnetic field frequency of 210 kHz, cell viability varied with the intensity of the applied alternating magnetic field, because the temperature increase of the culture medium with added complexes was dependent on magnetic field intensity. The HeLa cell death rate with added complexes was significantly greater as compared with that with MNPs alone. Cryptotanshinone, an anti-apoptotic factor blocker, was also added to cell cultures, which provided an additional anti-cancer cell effect. Thus, an anti-cancer cell effect using a combination of magnetic hyperthermia, an anti-Fas antibody and cryptotanshinone was established.

  10. Selection of apoptotic cell specific human antibodies from adult bone marrow.

    Directory of Open Access Journals (Sweden)

    Caroline Grönwall

    Full Text Available Autoreactive antibodies that recognize neo-determinants on apoptotic cells in mice have been proposed to have protective, homeostatic and immunoregulatory properties, although our knowledge about the equivalent antibodies in humans has been much more limited. In the current study, human monoclonal antibodies with binding specificity for apoptotic cells were isolated from the bone marrow of healthy adults using phage display technology. These antibodies were shown to recognize phosphorylcholine (PC-associated neo-determinants. Interestingly, three of the four identified apoptotic cell-specific antibody clones were encoded by VH3 region rearrangements with germline or nearly germline configuration without evidence of somatic hypermutation. Importantly, the different identified antibody clones had diverse heavy chain CDR3 and deduced binding surfaces as suggested by structure modeling. This may suggest a potentially great heterogeneity in human antibodies recognizing PC-related epitopes on apoptotic cells. To re-construct the postulated structural format of the parental anti-PC antibody, the dominant clone was also expressed as a recombinant human polymeric IgM, which revealed a substantially increased binding reactivity, with dose-dependent and antigen-inhibitable binding of apoptotic cells. Our findings may have implication for improved prognostic testing and therapeutic interventions in human inflammatory disease.

  11. Characterization of Peptide Antibodies by Epitope Mapping Using Resin-Bound and Soluble Peptides.

    Science.gov (United States)

    Trier, Nicole Hartwig

    2015-01-01

    Characterization of peptide antibodies through identification of their target epitopes is of utmost importance. Understanding antibody specificity at the amino acid level provides the key to understand the specific interaction between antibodies and their epitopes and their use as research and diagnostic tools as well as therapeutic agents. This chapter describes a straightforward strategy for mapping of continuous peptide antibody epitopes using resin-bound and soluble peptides. The approach combines three different types of peptide sets for full characterization of peptide antibodies: (1) overlapping peptides, used to locate antigenic regions; (2) truncated peptides, used to identify the minimal peptide length required for antibody binding; and (3) substituted peptides, used to identify the key residues important for antibody binding and to determine the specific contribution of key residues. For initial screening resin-bound peptides are used for epitope estimation, while soluble peptides subsequently are used for fine mapping. The combination of resin-bound peptides and soluble peptides for epitope mapping provides a time-sparing and straightforward approach for characterization of peptide antibodies.

  12. Replacing reprogramming factors with antibodies selected from combinatorial antibody libraries.

    Science.gov (United States)

    Blanchard, Joel W; Xie, Jia; El-Mecharrafie, Nadja; Gross, Simon; Lee, Sohyon; Lerner, Richard A; Baldwin, Kristin K

    2017-10-01

    The reprogramming of differentiated cells into induced pluripotent stem cells (iPSCs) is usually achieved by exogenous induction of transcription by factors acting in the nucleus. In contrast, during development, signaling pathways initiated at the membrane induce differentiation. The central idea of this study is to identify antibodies that can catalyze cellular de-differentiation and nuclear reprogramming by acting at the cell surface. We screen a lentiviral library encoding ∼100 million secreted and membrane-bound single-chain antibodies and identify antibodies that can replace either Sox2 and Myc (c-Myc) or Oct4 during reprogramming of mouse embryonic fibroblasts into iPSCs. We show that one Sox2-replacing antibody antagonizes the membrane-associated protein Basp1, thereby de-repressing nuclear factors WT1, Esrrb and Lin28a (Lin28) independent of Sox2. By manipulating this pathway, we identify three methods to generate iPSCs. Our results establish unbiased selection from autocrine combinatorial antibody libraries as a robust method to discover new biologics and uncover membrane-to-nucleus signaling pathways that regulate pluripotency and cell fate.

  13. Emerging therapeutic agents for lung cancer

    Directory of Open Access Journals (Sweden)

    Bhagirathbhai Dholaria

    2016-12-01

    Full Text Available Abstract Lung cancer continues to be the most common cause of cancer-related mortality worldwide. Recent advances in molecular diagnostics and immunotherapeutics have propelled the rapid development of novel treatment agents across all cancer subtypes, including lung cancer. Additionally, more pharmaceutical therapies for lung cancer have been approved by the US Food and Drug Administration in the last 5 years than in previous two decades. These drugs have ushered in a new era of lung cancer managements that have promising efficacy and safety and also provide treatment opportunities to patients who otherwise would have no conventional chemotherapy available. In this review, we summarize recent advances in lung cancer therapeutics with a specific focus on first in-human or early-phase I/II clinical trials. These drugs either offer better alternatives to drugs in their class or are a completely new class of drugs with novel mechanisms of action. We have divided our discussion into targeted agents, immunotherapies, and antibody drug conjugates for small cell lung cancer (SCLC and non-small-cell lung cancer (NSCLC. We briefly review the emerging agents and ongoing clinical studies. We have attempted to provide the most current review on emerging therapeutic agents on horizon for lung cancer.

  14. Therapeutic use of alpha-emitters

    Energy Technology Data Exchange (ETDEWEB)

    Lassmann, M. [Klinik und Poliklinik fuer Nuklearmedizin der Univ. Wuerzburg (Germany)

    2005-07-01

    In recent years there is a growing interest in the therapeutic use of {alpha}-emitters for patient treatment, {alpha}-particles have much higher energy and their range is only a few cell diameters. Their high LET and the limited ability of cells to repair DNA damage from {alpha}-radiation explain their high relative biological effectiveness and cytotoxicity. Potential {alpha}-emitting isotopes for therapeutic applications are {sup 224}Ra, {sup 223}Ra, {sup 213}Bi and {sup 211}At. The treatment with {alpha}-particles is focused upon targeted cancer therapy using radiolabeled monoclonal antibodies, on palliation of bone metastases or upon pain relief in patients with ankylosing spondylitis (AS). Examples for targeted cancer therapy are the treatment of melanoma with {sup 213}Bi and non-Hodgkin lymphoma with {sup 211}At. For metastatic bone pain palliation {sup 223}Ra was applied in a phase I clinical trial. For amelioration of pain in AS-patients {sup 224}Ra-chloride is used. This radiopharmaceutical is licensed for this particular application in Germany. Today there are some potential clinical applications for {alpha}-emitters although most of them are in the state of scientific, non-routine investigations. In-vivo dosimetry for risk assessment associated with this treatment is even more difficult to perform than for therapies using beta-emitting radiopharmaceuticals. (orig.)

  15. Salmonella and cancer: from pathogens to therapeutics.

    Science.gov (United States)

    Chorobik, Paulina; Czaplicki, Dominik; Ossysek, Karolina; Bereta, Joanna

    2013-01-01

    Bacterial cancer therapy is a concept more than 100 years old - yet, all things considered, it is still in early development. While the use of many passive therapeutics is hindered by the complexity of tumor biology, bacteria offer unique features that can overcome these limitations. Microbial metabolism, motility and sensitivity can lead to site-specific treatment, highly focused on the tumor and safe to other tissues. Activation of tumor-specific immunity is another important mechanism of such therapies. Several bacterial strains have been evaluated as cancer therapeutics so far, Salmonella Typhimurium being one of the most promising. S. Typhimurium and its derivatives have been used both as direct tumoricidal agents and as cancer vaccine vectors. VNP20009, an attenuated mutant of S. Typhimurium, shows significant native toxicity against murine tumors and was studied in a first-in-man phase I clinical trial for toxicity and anticancer activity. While proved to be safe in cancer patients, insufficient tumor colonization of VNP20009 was identified as a major limitation for further clinical development. Antibody-fragment-based targeting of cancer cells is one of the few approaches proposed to overcome this drawback.

  16. Molecular imaging of rheumatoid arthritis by radiolabelled monoclonal antibodies: new imaging strategies to guide molecular therapies

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    Malviya, G.; Dierckx, R.A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Conti, F. [Rheumatology Unit, I Faculty of Medicine and Surgery, Sapienza University of Rome (Italy); Chianelli, M. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Unit of Nuclear Medicine, Regina apostolorum Hospital, Albano, Rome (Italy); Scopinaro, F. [Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy); Signore, A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy)

    2010-02-15

    The closing of the last century opened a wide variety of approaches for inflammation imaging and treatment of patients with rheumatoid arthritis (RA). The introduction of biological therapies for the management of RA started a revolution in the therapeutic armamentarium with the development of several novel monoclonal antibodies (mAbs), which can be murine, chimeric, humanised and fully human antibodies. Monoclonal antibodies specifically bind to their target, which could be adhesion molecules, activation markers, antigens or receptors, to interfere with specific inflammation pathways at the molecular level, leading to immune-modulation of the underlying pathogenic process. These new generation of mAbs can also be radiolabelled by using direct or indirect method, with a variety of nuclides, depending upon the specific diagnostic application. For studying rheumatoid arthritis patients, several monoclonal antibodies and their fragments, including anti-TNF-{alpha}, anti-CD20, anti-CD3, anti-CD4 and anti-E-selectin antibody, have been radiolabelled mainly with {sup 99m}Tc or {sup 111}In. Scintigraphy with these radiolabelled antibodies may offer an exciting possibility for the study of RA patients and holds two types of information: (1) it allows better staging of the disease and diagnosis of the state of activity by early detection of inflamed joints that might be difficult to assess; (2) it might provide a possibility to perform 'evidence-based biological therapy' of arthritis with a view to assessing whether an antibody will localise in an inflamed joint before using the same unlabelled antibody therapeutically. This might prove particularly important for the selection of patients to be treated since biological therapies can be associated with severe side-effects and are considerably expensive. This article reviews the use of radiolabelled mAbs in the study of RA with particular emphasis on the use of different radiolabelled monoclonal antibodies for

  17. C-C chemokine receptor-7 mediated endocytosis of antibody cargoes into intact cells

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    Xavier eCharest-Morin

    2013-09-01

    Full Text Available The C-C chemokine receptor-7 (CCR7 is a G protein coupled receptor that has a role in leukocyte homing, but that is also expressed in aggressive tumor cells. Preclinical research supports that CCR7 is a valid target in oncology. In view of the increasing availability of therapeutic monoclonal antibodies that carry cytotoxic cargoes, we studied the feasibility of forcing intact cells to internalize known monoclonal antibodies by exploiting the cycle of endocytosis and recycling triggered by the CCR7 agonist CCL19. Firstly, an anti-CCR7 antibody (CD197; clone 150503 labeled surface recombinant CCR7 expressed in intact HEK 293a cells and the fluorescent antibody was internalized following CCL19 treatment. Secondly, a recombinant myc-tagged CCL19 construction was exploited along the anti-myc monoclonal antibody 4A6. The myc-tagged ligand was produced as a conditioned medium of transfected HEK 293a cells that contained the equivalent of 430 ng/ml of immunoreactive CCL19 (average value, ELISA determination. CCL19-myc, but not authentic CCL19, carried the fluorophore-labeled antibody 4A6 into other recipient cells that expressed recombinant CCR7 (microscopy, cytofluorometry. The immune complexes were apparent in endosomal structures, colocalized well with the small GTPase Rab5 and progressed toward Rab7-positive endosomes. A dominant negative form of Rab5 (GDP-locked inhibited this endocytosis. Further, endosomes in CCL19-myc- or CCL19-stimulated cells were positive for β-arrestin2, but rarely for β-arrestin1. Following treatment with CCL19-myc and the 4A6 antibody, the melanoma cell line A375 that expresses endogenous CCR7 was specifically stained using a secondary peroxidase-conjugated antibody. Agonist-stimulated CCR7 can transport antibody-based cargoes, with possible therapeutic applications in oncology.

  18. Impact of Antibodies and Strain Polymorphisms on Cytomegalovirus Entry and Spread in Fibroblasts and Epithelial Cells.

    Science.gov (United States)

    Cui, Xiaohong; Freed, Daniel C; Wang, Dai; Qiu, Ping; Li, Fengsheng; Fu, Tong-Ming; Kauvar, Lawrence M; McVoy, Michael A

    2017-07-01

    and vaccines targeting humoral responses are under development for prophylactic or therapeutic use. The findings reported here (i) confirm that cell-to-cell spread of CMV is sensitive to antibody inhibition in epithelial cells but not fibroblasts, (ii) demonstrate that antibodies can restrict the formation in vitro of syncytiumlike structures that resemble syncytial cytomegalic cells that are associated with CMV disease in vivo, and (iii) reveal that neutralization of CMV by antibodies to certain epitopes in gH or gH/gL is both strain and cell type dependent and can be governed by polymorphisms in sequences external to the epitopes. These findings serve to elucidate the mechanisms of CMV entry, spread, and antibody evasion and may have important implications for the development of CMV vaccines and immunotherapeutics. Copyright © 2017 American Society for Microbiology.

  19. [Monoclonal antibodies against PCSK9: from bench to clinic].

    Science.gov (United States)

    Guijarro Herraiz, Carlos

    2016-05-01

    Antibodies are glycoproteins with high specificity binding to multiple antigens due to the large number of structural conformations of the variable chains. Hybridoma technology (fusion of myeloma cells with immunoglobulin-producing lymphocytes) has allowed the synthesis of large quantities of unique antibodies (monoclonal [mAb]). mAbs were initially murine. Subsequently, chimeric mAbs were developed, followed by humanized mAbs and finally human mAbs. The high selectivity and good tolerance of human mAbs allows their therapeutic administration to block specific exogenous or endogenous molecules. Selective human mAbs to the catalytic domain of PCSK9 have recently been developed. These antibodies block PCSK9, favour low-density lipoprotein receptor recycling and markedly reduce circulating cholesterol. Preliminary studies indicate that lowering cholesterol through anti-PCSK9 antibodies may significantly reduce the cardiovascular complications of arteriosclerosis. Copyright © 2016 Elsevier España, S.L.U. y Sociedad Española de Arteriosclerosis. All rights reserved.

  20. History of antibody therapy for non-Hodgkin's lymphoma.

    Science.gov (United States)

    Forero, Andres; Lobuglio, Albert F

    2003-12-01

    Monoclonal antibodies (mAbs) were the first successful targeted therapy for cancer. In contrast to the nonspecific nature of most chemotherapy, antibodies bind with high specificity to cell-surface antigens, resulting in targeted killing of malignant cells, relative sparing of normal tissues, and low toxicity. Antibody therapy has undergone substantial development since Ehrlich's notion of a "magic bullet," in 1890. It was not until the 1970s, however, that mAbs became viable as therapeutic tools and clinical studies showed them to be effective. The results were most impressive in hematologic malignancies, especially B-cell non-Hodgkin's lymphoma. In 1997, rituximab (Rituxan; Genentech Inc, South San Francisco, CA, and Biogen Idec Inc, Cambridge, MA) became the first mAb approved by the US Food and Drug Administration for use in the treatment of cancer. The first approval for a radiolabeled antibody to treat cancer was in 2002 for (90)Y ibritumomab tiuxetan (Zevalin; Biogen Idec). This is a conjugate of an anti-CD20 mAb (ibritumomab, the murine parent of rituximab) with the beta-emitter radionuclide (90)Y. (90)Y ibritumomab tiuxetan has been shown to be safe and effective in the indicated patient population. Other radioimmunoconjugates are being investigated for the treatment of non-Hodgkin's lymphoma, as are several immunotoxins. This article reviews important events in the development of mAb therapy and radioimmunotherapy for B-cell non-Hodgkin's lymphoma.