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Wang X, Kopec AK, Collinge M, David R, Grant C, Hardwick RN, Navratil A, Patel N, Rowan W, Marshall N. Application of Immunocompetent Microphysiological Systems in Drug Development: Current Perspective and Recommendations. ALTEX 2022; 40:314–336. [PMID: 36044561 DOI: 10.14573/altex.2205311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/25/2022] [Indexed: 11/23/2022]
Abstract
Immune responses are heavily involved in the regulation and pathogenesis of human diseases, including infectious diseases, inflammatory and autoimmune conditions, cancer, neurological disorders, and cardiometabolic syndromes. The immune system is considered a double-edged sword serving as a powerful host defense mechanism against infection and cancerous cells and causing detrimental tissue damage when the immune response is exaggerated or uncontrollable. One of the challenges in studying the efficacy and toxicity of drugs that target or modulate the immune system is the lack of suitable preclinical human models that are predictive of human response. Recent advancements in human microphysiological systems (MPS) have provided a promising in vitro platform to evaluate the response of immune organs ex vivo, to investigate the interaction of immune cells with non-lymphoid tissue cells, and to reduce the reliance on animals in preclinical studies. The development, regulation, trafficking, and responses of immune cells have been extensively studied in preclinical animal models and clinically, providing a wealth of knowledge by which to evaluate new in vitro models. Therefore, the application of immunocompetent MPS in drug discovery and development should first verify that the immune response in an MPS model recapitulates the complexity of the human immune physiology. This manuscript reviews biological functions of immune organ systems and tissue-resident immune cells and discusses contexts-of-use for commonly used immunocompetent and immune organ MPS models. Current perspective and recommendations are provided to guide the continued development of immune organ and immunocompetent MPS models and their application in drug discovery and development.
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Affiliation(s)
- Xiaoting Wang
- Translational Safety & Bioanalytical Sciences, Amgen Research, Amgen, Inc., South San Francisco, CA, USA
| | - Anna K Kopec
- Drug Safety Research & Development, Pfizer, Inc., Groton, CT, USA
| | - Mark Collinge
- Drug Safety Research & Development, Pfizer, Inc., Groton, CT, USA
| | - Rhiannon David
- Safety Innovation, Clinical Pharmacology & Safety Sciences, R&D, AstraZeneca, Cambridge, UK
| | | | - Rhiannon N Hardwick
- Translational Safety Sciences, Theravance Biopharma US, Inc., South San Francisco, CA, USA
- current affiliation: Discovery Toxicology, Preclinical Candidate Optimization, Bristol Myers Squibb, San Diego, CA, USA
| | - Aaron Navratil
- Biology and Pharmacology, Theravance Biopharma US, Inc., South San Francisco, CA, USA
| | - Nirav Patel
- Preclinical Safety, Research and Development, Sanofi-Aventis US, LLC, Framingham, MA, USA
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McCarthy S, Rowan W, Kahma N, Lynch L, Ertiö TP. Open e-learning platforms and the design–reality gap: an affordance theory perspective. ITP 2021. [DOI: 10.1108/itp-06-2021-0501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PurposeThe dropout rates of open e-learning platforms are often cited as high as 97%, with many users discontinuing their use after initial acceptance. This study aims to explore this anomaly through the lens of affordances theory, revealing design–reality gaps between users' diverse goals and the possibilities for action provided by an open IT artefact.Design/methodology/approachA six-month case study was undertaken to investigate the design implications of user-perceived affordances in an EU sustainability project which developed an open e-learning platform for citizens to improve their household energy efficiency. Thematic analysis was used to reveal the challenges of user continuance behaviour based on how an open IT artefact supports users in achieving individual goals (e.g. reducing energy consumption in the home) and collective goals (lessening the carbon footprint of society).FindingsBased on the findings, the authors inductively reveal seven affordances related to open e-learning platforms: informing, assessment, synthesis, emphasis, clarity, learning pathway and goal-planning. The findings centre on users' perception of these affordances, and the extent to which the open IT artefact catered to the goals and constraints of diverse user groups. Open IT platform development is further discussed from an iterative and collaborative perspective in order to explore different possibilities for action.Originality/valueThe study contributes towards research on open IT artefact design by presenting key learnings on how the designers of e-learning platforms can bridge design–reality gaps through exploring affordance personalisation for diverse user groups. This can inform the design of open IT artefacts to help ensure that system features match the expectations and contextual constraints of users through clear action-oriented possibilities.
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Rowan W, O'Connor Y, Lynch L, Heavin C. Comprehension, Perception, and Projection. J ORGAN END USER COM 2021. [DOI: 10.4018/joeuc.286766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Health social networks (HSNs) allow individuals with health information needs to connect and discuss health-related issues online. Political-technology intertwinement (e.g. GDPR and Digital Technology) highlights that users need to be aware, understand, and willing to provide electronic consent (eConsent) when sharing personal information online. The objective of this study is to explore the ‘As-Is’ factors which impact individuals’ decisional autonomy when consenting to the privacy policy (PP) and Terms and Conditions (T&Cs) on a HSN. We use a Situational Awareness (SA) lens to examine decision autonomy when providing eConsent. A mixed-methods approach reveals that technical and privacy comprehension, user perceptions, and projection of future consequences impact participants’ decision autonomy in providing eConsent. Without dealing with the privacy paradox at the outset, decision awareness and latterly decision satisfaction is negatively impacted. Movement away from clickwrap online consent to customised two-way engagement is the way forward for the design of eConsent.
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Holloway PM, Willaime-Morawek S, Siow R, Barber M, Owens RM, Sharma AD, Rowan W, Hill E, Zagnoni M. Advances in microfluidic in vitro systems for neurological disease modeling. J Neurosci Res 2021; 99:1276-1307. [PMID: 33583054 DOI: 10.1002/jnr.24794] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/21/2020] [Accepted: 12/19/2020] [Indexed: 12/19/2022]
Abstract
Neurological disorders are the leading cause of disability and the second largest cause of death worldwide. Despite significant research efforts, neurology remains one of the most failure-prone areas of drug development. The complexity of the human brain, boundaries to examining the brain directly in vivo, and the significant evolutionary gap between animal models and humans, all serve to hamper translational success. Recent advances in microfluidic in vitro models have provided new opportunities to study human cells with enhanced physiological relevance. The ability to precisely micro-engineer cell-scale architecture, tailoring form and function, has allowed for detailed dissection of cell biology using microphysiological systems (MPS) of varying complexities from single cell systems to "Organ-on-chip" models. Simplified neuronal networks have allowed for unique insights into neuronal transport and neurogenesis, while more complex 3D heterotypic cellular models such as neurovascular unit mimetics and "Organ-on-chip" systems have enabled new understanding of metabolic coupling and blood-brain barrier transport. These systems are now being developed beyond MPS toward disease specific micro-pathophysiological systems, moving from "Organ-on-chip" to "Disease-on-chip." This review gives an outline of current state of the art in microfluidic technologies for neurological disease research, discussing the challenges and limitations while highlighting the benefits and potential of integrating technologies. We provide examples of where such toolsets have enabled novel insights and how these technologies may empower future investigation into neurological diseases.
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Affiliation(s)
- Paul M Holloway
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Richard Siow
- King's British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Melissa Barber
- King's British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine & Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Róisín M Owens
- Department Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, UK
| | - Anup D Sharma
- New Orleans BioInnovation Center, AxoSim Inc., New Orleans, LA, USA
| | - Wendy Rowan
- Novel Human Genetics Research Unit, GSK R&D, Stevenage, UK
| | - Eric Hill
- School of Life and Health sciences, Aston University, Birmingham, UK
| | - Michele Zagnoni
- Electronic and Electrical Engineering, University of Strathclyde, Glasgow, UK
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Ekert JE, Deakyne J, Pribul-Allen P, Terry R, Schofield C, Jeong CG, Storey J, Mohamet L, Francis J, Naidoo A, Amador A, Klein JL, Rowan W. Recommended Guidelines for Developing, Qualifying, and Implementing Complex In Vitro Models (CIVMs) for Drug Discovery. SLAS Discov 2020; 25:1174-1190. [PMID: 32495689 DOI: 10.1177/2472555220923332] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The pharmaceutical industry is continuing to face high research and development (R&D) costs and low overall success rates of clinical compounds during drug development. There is an increasing demand for development and validation of healthy or disease-relevant and physiological human cellular models that can be implemented in early-stage discovery, thereby shifting attrition of future therapeutics to a point in discovery at which the costs are significantly lower. There needs to be a paradigm shift in the early drug discovery phase (which is lengthy and costly), away from simplistic cellular models that show an inability to effectively and efficiently reproduce healthy or human disease-relevant states to steer target and compound selection for safety, pharmacology, and efficacy questions. This perspective article covers the various stages of early drug discovery from target identification (ID) and validation to the hit/lead discovery phase, lead optimization, and preclinical safety. We outline key aspects that should be considered when developing, qualifying, and implementing complex in vitro models (CIVMs) during these phases, because criteria such as cell types (e.g., cell lines, primary cells, stem cells, and tissue), platform (e.g., spheroids, scaffolds or hydrogels, organoids, microphysiological systems, and bioprinting), throughput, automation, and single and multiplexing endpoints will vary. The article emphasizes the need to adequately qualify these CIVMs such that they are suitable for various applications (e.g., context of use) of drug discovery and translational research. The article ends looking to the future, in which there is an increase in combining computational modeling, artificial intelligence and machine learning (AI/ML), and CIVMs.
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Affiliation(s)
- Jason E Ekert
- In Vitro In Vivo Translation, Research, Pharmaceutical R&D, GlaxoSmithKline, Collegeville, PA, USA
| | - Julianna Deakyne
- In Vitro In Vivo Translation, Research, Pharmaceutical R&D, GlaxoSmithKline, Collegeville, PA, USA
| | - Philippa Pribul-Allen
- In Vitro In Vivo Translation, Research, Pharmaceutical R&D, GlaxoSmithKline, Ware, UK
| | - Rebecca Terry
- In Vitro In Vivo Translation, Research, Pharmaceutical R&D, GlaxoSmithKline, Ware, UK
| | - Christopher Schofield
- Functional Genomics, Medicinal Science and Technology, Pharmaceutical R&D, GlaxoSmithKline, Stevenage, UK
| | | | - Joanne Storey
- Research Office of Animal Welfare, Ethics and Strategy, Research, Pharmaceutical R&D, GlaxoSmithKline, Stevenage, UK
| | - Lisa Mohamet
- Functional Genomics, Medicinal Science and Technology, Pharmaceutical R&D, GlaxoSmithKline, Stevenage, UK
| | - Jo Francis
- Screening Profiling and Mechanistic Biology, Medicinal Science and Technology, Pharmaceutical R&D, GlaxoSmithKline, Stevenage, UK
| | - Anita Naidoo
- In Vitro In Vivo Translation, Research, Pharmaceutical R&D, GlaxoSmithKline, Ware, UK
| | - Alejandro Amador
- Functional Genomics, Medicinal Science and Technology, Pharmaceutical R&D, GlaxoSmithKline, Collegeville, PA, USA
| | - Jean-Louis Klein
- Novel Human Genetics, Research, Pharmaceutical R&D, GlaxoSmithKline, Collegeville, PA, USA
| | - Wendy Rowan
- Novel Human Genetics, Research, Pharmaceutical R&D, GlaxoSmithKline, Stevenage, UK
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McCarthy S, Rowan W, Lynch L, Fitzgerald C. Blended Stakeholder Participation for Responsible Information Systems Research. CAIS 2020. [DOI: 10.17705/1cais.04733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Greenwald M, Basse N, Bonoli P, Bravenec R, Edlund E, Ernst D, Fiore C, Granetz R, Hubbard A, Hughes J, Hutchinson I, Irby J, LaBombard B, Lin L, Lin Y, Lipschultz B, Marmar E, Mikkelsen D, Mossessian D, Phillips P, Porkolab M, Rice J, Rowan W, Scott S, Snipes J, Terry J, Wolfe S, Wukitch S, Zhurovich K. Confinement and Transport Research in Alcator C-Mod. Fusion Science and Technology 2017. [DOI: 10.13182/fst07-a1422] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- M. Greenwald
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - N. Basse
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - P. Bonoli
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | | | - E. Edlund
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - D. Ernst
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - C. Fiore
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - R. Granetz
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - A. Hubbard
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - J. Hughes
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - I. Hutchinson
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - J. Irby
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - B. LaBombard
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - L. Lin
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - Y. Lin
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - B. Lipschultz
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - E. Marmar
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - D. Mikkelsen
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - D. Mossessian
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | | | - M. Porkolab
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - J. Rice
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - W. Rowan
- University of Texas, Austin, Texas
| | - S. Scott
- Princeton Plasma Physics Laboratory, Princeton, New Jersey
| | - J. Snipes
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - J. Terry
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - S. Wolfe
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - S. Wukitch
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
| | - K. Zhurovich
- Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02138
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9
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Rowan W, Austin M, Beno J, Ellis R, Feder R, Ouroua A, Patel A, Phillips P. Electron cyclotron emission diagnostic for ITER. Rev Sci Instrum 2010; 81:10D935. [PMID: 21033963 DOI: 10.1063/1.3496978] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Electron temperature measurements and electron thermal transport inferences will be critical to the nonactive and deuterium phases of ITER operation and will take on added importance during the alpha heating phase. The diagnostic must meet stringent criteria on spatial coverage and spatial resolution during full field operation. During the early phases of operation, it must operate equally well at half field. The key to the diagnostic is the front end design. It consists of a quasioptical antenna and a pair of calibration sources. The radial resolution of the diagnostic is less than 0.06 m. The spatial coverage extends at least from the core to the separatrix with first harmonic O-mode being used for the core and second harmonic X-mode being used for the pedestal. The instrumentation used for the core measurement at full field can be used for detection at half field by changing the detected polarization. Intermediate fields are accessible. The electron cyclotron emission systems require in situ calibration, which is provided by a novel hot calibration source. The critical component for the hot calibration source, the emissive surface, has been successfully tested. A prototype hot calibration source has been designed, making use of extensive thermal and mechanical modeling.
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Affiliation(s)
- W Rowan
- Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712, USA.
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11
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Rowan W. Experiments in Bird Migration: III. The Effects of Artificial Light, Castration and Certain Extracts on the Autumn Movements of the American Crow(Corvus brachyrhynchis). Proc Natl Acad Sci U S A 2006; 18:639-54. [PMID: 16577488 PMCID: PMC1076302 DOI: 10.1073/pnas.18.11.639] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- W Rowan
- Department of Zoölogy, University of Alberta
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12
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Affiliation(s)
- W Rowan
- Department of Zoölogy, University of Alberta
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Rowan W, Tite J, Topley P, Brett SJ. Cross-linking of the CAMPATH-1 antigen (CD52) mediates growth inhibition in human B- and T-lymphoma cell lines, and subsequent emergence of CD52-deficient cells. Immunology 1998; 95:427-36. [PMID: 9824507 PMCID: PMC1364410 DOI: 10.1046/j.1365-2567.1998.00615.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The CAMPATH-1H (CD52) antigen is a 21 000-28 000 MW glycopeptide antigen that is highly expressed on T and B lymphocytes and is coupled to the membrane by a glycosylphosphatidylinositol (GPI) anchoring structure. The humanized CAMPATH-1H anti-CD52 antibody is extremely effective at mediating depletion of both normal and tumorigenic lymphocytes in vivo and has been used in clinical trials for lymphoid malignancy and rheumatoid arthritis. Cross-linking GPI-anchored molecules, including CD52, on the surface of T lymphocytes in the presence of phorbol 12-myristate 13-acetate or anti-CD3, results in cellular activation. In the present study we have investigated the functional effects of cross-linking CD52 on T and B tumour cell lines. Cross-linking CD52 on either a B-cell line, Wien 133, which expresses high levels of endogenous CD52 or Jurkat T cells transfected and selected to express high levels of CD52 resulted in growth inhibition. This effect showed slower kinetics and occurred in a lower percentage of cells than growth inhibition stimulated via T- or B-cell receptors. Growth inhibition of the Wien 133 line was followed by the induction of apoptosis, which appeared independent of the Fas/Fas L pathway. Wien 133 cells surviving anti-CD52 treatment were selected and cloned and found to have down-regulated CD52 expression, with a characteristic biphasic pattern of 10% CD52-positive, 90% negative by fluorescence-activated cell sorter analysis. Interestingly, surface expression of other GPI-linked molecules, such as CD59 and CD55, was also down-regulated, but other transmembrane molecules such as surface IgM, CD19, CD20, HLA-DR were unaffected. The present study and previous work show that this is due to a defect in the synthesis of mature GPI precursors. Separation of CD52-positive and negative populations in vitro resulted in a rapid redistribution to the mixed population. Injection of CD52-negative cells into nude mice to form a subcutaneous tumour resulted in a substantial increase in expression of CD52. These results suggest that the defect in the Wien 133 cells is reversible, although the molecular mechanism is not clear. These observations have relevance to the clinical situation as a similar GPI-negative phenotype has been reported to occur in lymphocytes following CAMPATH-1H treatment in vivo.
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MESH Headings
- Animals
- Antigens, CD/metabolism
- Antigens, Neoplasm/metabolism
- Apoptosis/immunology
- Blotting, Western
- CD52 Antigen
- Cell Division/immunology
- Glycoproteins/metabolism
- Humans
- Immunoglobulin M/immunology
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/pathology
- Lymphoma, T-Cell/immunology
- Lymphoma, T-Cell/pathology
- Mice
- Mice, Nude
- Neoplasm Transplantation
- Receptors, Antigen, B-Cell/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- W Rowan
- Immunology Unit, Glaxo-Wellcome Medicines Research Centre, Gunnels Wood Road, Stevenage, Herts, UK
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Brett SJ, Rowan W, Smith M, Bartholomew M, Tite JP. Differential functional effects of a humanized anti-CD4 antibody on resting and activated human T cells. Immunol Suppl 1997; 91:346-53. [PMID: 9301522 PMCID: PMC1364002 DOI: 10.1046/j.1365-2567.1997.00265.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A fully humanized immunoglobulin G1 (IgG1) anti-CD4 monoclonal antibody is currently being evaluated in phase I/II clinical trials for rheumatoid arthritis. In order to understand the mode of action of this antibody in vivo, we have carried out a detailed functional analysis in vitro of the effects of this antibody on T-cell activation. The anti-CD4 antibody was found to inhibit both antigen-specific responses involving recognition of human leucocyte antigen (HLA) class II and processed antigenic peptides as well as non-class II dependent responses via anti-CD3 antibodies. The antibody did not cause total blockade of T-cell proliferation, but rather induced a shift in the dose-response curve, decreasing the sensitivity of cells to antigen or anti-CD3-mediated stimulation. The antibody appears to allow at least a partial early signal into the T cell as it does not inhibit the increase in tyrosine phosphorylation induced by anti-CD3 antibodies. A comparison of the intact antibody with that of either the F(ab')2 fragment or an engineered non-Fc receptor (FcR) binding form revealed that the intact antibody was the most effective at inhibiting proliferation of resting peripheral blood CD4+ T cells. However, this difference was only apparent when excess antibody was removed from culture prior to antigen or anti-CD3 mediated stimulation. The intact antibody induced both CD4 down-modulation and increases in CD4-associated tyrosine phosphorylation of resting CD4+ T cells, which were not seen with the non-FcR binding versions, which may account for the enhanced potency of the intact antibody at inhibiting T-cell activation. Interestingly, the anti-CD4 antibody induced a differential effect on activated CD4+ T cell clones compared with resting CD4+ T cells with respect to degree of CD4 cross-linking required to induce functional effects in the T cell. Both intact and non-FcR binding antibodies were equally effective at inhibiting T-cell proliferation of activated T-cell clones. In addition CD4 down-modulation and increased CD4-associated tyrosine phosphorylation were observed with T-cell clones in the absence of secondary cross-linking. Such observations may be of relevance when studying the effects of the antibody at sites of inflammation, where there will be CD4+ T cells of differing activation states as well as varying numbers of FcR positive cells.
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Affiliation(s)
- S J Brett
- Immunology Unit, Glaxo-Wellcome Medicines Research Centre, Stevenage, UK
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Brett SJ, Baxter G, Cooper H, Rowan W, Regan T, Tite J, Rapson N. Emergence of CD52-, glycosylphosphatidylinositol-anchor-deficient lymphocytes in rheumatoid arthritis patients following Campath-1H treatment. Int Immunol 1996; 8:325-34. [PMID: 8671618 DOI: 10.1093/intimm/8.3.325] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
CD52 is a glycosylphosphatidyl-inositol (GPI)-linked glycoprotein expressed at high levels on normal T and B lymphocytes and at lower levels on monocytes, while being absent on granulocytes and bone marrow stem cell precursors. The emergence of CD52- lymphocytes of both T and B cell lineages was observed in three out of 25 rheumatoid arthritis patients treated with teh humanized antibody Campath-1H in phase II clinical trial. Whereas the majority of CD52- B cells had disappeared from the peripheral blood by 3 months post-treatment, both CD52- CD4+ and CD8+ T cells persisted in the circulation for at least 20 months. In the two patients that were tested, the GPI-anchored surface molecules CD55 and CD59 were also absent on the CD52- cells, although expression of other cell surface transmembrane, proteins (CD3, CD4 and CD2) was unaffected. The CD52- cells maintained a stable phenotype in vitro despite repeated re-stimulation in culture. Both CD52- and C52+ clones, established from one of the patients, responded to a similar extent to several T cell mitogens, as assessed by proliferation, suggesting that a general defect in expression of GPI-linked molecules does not impair T cell activation. These data show that an immune attack against a GPI-anchored surface molecule can result in the selection of a GPI-anchor-deficient cell population. Despite the persistence of CD52- T cells in the peripheral blood, no adverse reactions associated with the presence of these cells were noted in any of the patients; in fact they responded with longer remission times after Campath-1H treatment than the other patients in the trial.
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MESH Headings
- Adult
- Alemtuzumab
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antibodies, Neoplasm/pharmacology
- Antibodies, Neoplasm/therapeutic use
- Antigens, CD/biosynthesis
- Antigens, Neoplasm
- Arthritis, Rheumatoid/drug therapy
- Arthritis, Rheumatoid/immunology
- CD4-Positive T-Lymphocytes/chemistry
- CD52 Antigen
- CD8-Positive T-Lymphocytes/chemistry
- Cells, Cultured
- Female
- Glycoproteins
- Humans
- Lymphocyte Activation
- Lymphocyte Subsets/immunology
- Lymphocytes/chemistry
- Lymphocytes/immunology
- Male
- Middle Aged
- Time Factors
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Affiliation(s)
- S J Brett
- Molecular Immunology Group, Wellcome Research Laboratories, Kent, UK
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Abstract
Stenoses in branch vessels which originate at acute angle to the main vessel represent a technically challenging anatomy for the performance of balloon angioplasty [PTCA]. We report a novel technique utilizing a distally placed perfusion balloon that facilitated guidewire placement and subsequent balloon angioplasty of a branch vessel stenosis.
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Affiliation(s)
- G Gershony
- Cardiac Catheterization Laboratories, University of California, Davis Medical Center, Sacramento 95817, USA
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Sims MJ, Hassal DG, Brett S, Rowan W, Lockyer MJ, Angel A, Lewis AP, Hale G, Waldmann H, Crowe JS. A humanized CD18 antibody can block function without cell destruction. The Journal of Immunology 1993. [DOI: 10.4049/jimmunol.151.4.2296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Leukocyte integrins are intimately involved in transient adherence of leukocytes to endothelium and to each other in the processes of extravasation and cell activation. In this study, seven mAb directed against human CD11a and two mAb directed against human CD18, the alpha- and beta-chains of the leukocyte functional Ag-1 molecule, respectively, were analyzed for their ability to inhibit several leukocyte functional Ag-1-mediated interactions. The best blocking mAb in these studies, a rat anti-human CD18, YFC51.1, was subsequently humanized by complementarily-determining region grafting, associated with human C regions and expressed. The humanized mAb was shown to maintain binding for human CD18. Even though the humanized mAb was an IgG1 isotype it still retained the functional blocking characteristics of the rat mAb while failing to mediate cell killing. The IgG1 mAb was unable to bind human Clq and could block but did not mediate antibody-dependent cellular cytotoxicity.
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Affiliation(s)
- M J Sims
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - D G Hassal
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - S Brett
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - W Rowan
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - M J Lockyer
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - A Angel
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - A P Lewis
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - G Hale
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - H Waldmann
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
| | - J S Crowe
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
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Sims MJ, Hassal DG, Brett S, Rowan W, Lockyer MJ, Angel A, Lewis AP, Hale G, Waldmann H, Crowe JS. A humanized CD18 antibody can block function without cell destruction. J Immunol 1993; 151:2296-308. [PMID: 7688398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Leukocyte integrins are intimately involved in transient adherence of leukocytes to endothelium and to each other in the processes of extravasation and cell activation. In this study, seven mAb directed against human CD11a and two mAb directed against human CD18, the alpha- and beta-chains of the leukocyte functional Ag-1 molecule, respectively, were analyzed for their ability to inhibit several leukocyte functional Ag-1-mediated interactions. The best blocking mAb in these studies, a rat anti-human CD18, YFC51.1, was subsequently humanized by complementarily-determining region grafting, associated with human C regions and expressed. The humanized mAb was shown to maintain binding for human CD18. Even though the humanized mAb was an IgG1 isotype it still retained the functional blocking characteristics of the rat mAb while failing to mediate cell killing. The IgG1 mAb was unable to bind human Clq and could block but did not mediate antibody-dependent cellular cytotoxicity.
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Affiliation(s)
- M J Sims
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, United Kingdom
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19
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Abstract
A recombinant baculovirus-expressed hybrid protein containing epitopes for the C-terminal fragment of the Plasmodium falciparum precursor to the major merozoite surface antigens (PMMSA) and the tetrapeptide repeats of the circumsporozoite protein (CSP) was assessed for its immunogenicity. Murine MHC-II restriction of the antibody response to the CSP repeats was not overcome by the PMMSA component, the response to which showed no restriction. In an adjuvant trial the highest antibody titres in rabbits to both components of the hybrid were obtained using Freund's adjuvant. Lack of a boosting antibody response to the CSP repeats appeared to be linked to the conformation of the PMMSA component. Formulation of the hybrid protein into Iscoms gave antibody titres of only short duration to both components.
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Affiliation(s)
- M J Lockyer
- Department of Cell Biology, Wellcome Research Laboratories, Beckenham, Kent
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Abstract
Resolution and contrast recovery in planar nuclear images at depth with a high purity germanium (HPGe) camera has been achieved through use of a weighted back projection (WBP) method. The algorithm can be derived from Bayes' theorem using the point spread function of the camera. The variations in the formulation of WBP (one single pass and two iterative procedures) are presented with the characteristics and performance of each method. The evaluation procedure determines the behaviour of signal-to-noise ratio, contrast and texture after application of the algorithm. Both real and simulated cold lesions obtained with the HPGe camera are studied with sizes ranging from 3 mm to 17 mm and background count densities from 100 to 6400 counts cm2. Application of WBP is shown to increase spatial resolution and contrast without a concomitant reduction in signal-to-noise ratio. Images obtained with the HPGe camera and processed with WBP are presented. The algorithm has been applied to the scintillation camera, yielding significant resolution and contrast recovery despite the presence of scatter and textured noise present in the HPGe images.
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Rowan W. EUTHANASIA. Can Med Assoc J 1954; 71:505. [PMID: 20324945 PMCID: PMC1824952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Rowan W, Wolff E, Sulman PL, Pearson K, Isaacs E, Elderton EM, Tildesley M. On the Nest and Eggs of the Common Tern (S. Fluviatilis). A Cooperative Study. Biometrika 1919. [DOI: 10.2307/2331774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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