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Lynch AM, Howe J, Hildebrand D, Harvey JS, Burman M, Harte DSG, Chen L, Kmett C, Shi W, McHugh CF, Patel KK, Junnotula V, Kenny J, Haworth R, Wills JW. N-Nitrosodimethylamine investigations in Muta™Mouse define point-of-departure values and demonstrate less-than-additive somatic mutant frequency accumulations. Mutagenesis 2024; 39:96-118. [PMID: 38183622 DOI: 10.1093/mutage/geae001] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 01/05/2024] [Indexed: 01/08/2024] Open
Abstract
The N-nitrosamine, N-nitrosodimethylamine (NDMA), is an environmental mutagen and rodent carcinogen. Small levels of NDMA have been identified as an impurity in some commonly used drugs, resulting in several product recalls. In this study, NDMA was evaluated in an OECD TG-488 compliant Muta™Mouse gene mutation assay (28-day oral dosing across seven daily doses of 0.02-4 mg/kg/day) using an integrated design that assessed mutation at the transgenic lacZ locus in various tissues and at the endogenous Pig-a gene-locus, along with micronucleus frequencies in peripheral blood. Liver pathology was determined together with NDMA exposure in blood and liver. The additivity of mutation induction was assessed by including two acute single-dose treatment groups (i.e. 5 and 10 mg/kg dose on Day 1), which represented the same total dose as two of the repeat dose treatment groups. NDMA did not induce statistically significant increases in mean lacZ mutant frequency (MF) in bone marrow, spleen, bladder, or stomach, nor in peripheral blood (Pig-a mutation or micronucleus induction) when tested up to 4 mg/kg/day. There were dose-dependent increases in mean lacZ MF in the liver, lung, and kidney following 28-day repeat dosing or in the liver and kidney after a single dose (10 mg/kg). No observed genotoxic effect levels (NOGEL) were determined for the positive repeat dose-response relationships. Mutagenicity did not exhibit simple additivity in the liver since there was a reduction in MF following NDMA repeat dosing compared with acute dosing for the same total dose. Benchmark dose modelling was used to estimate point of departure doses for NDMA mutagenicity in Muta™Mouse and rank order target organ tissue sensitivity (liver > kidney or lung). The BMD50 value for liver was 0.32 mg/kg/day following repeat dosing (confidence interval 0.21-0.46 mg/kg/day). In addition, liver toxicity was observed at doses of ≥ 1.1 mg/kg/day NDMA and correlated with systemic and target organ exposure. The integration of these results and their implications for risk assessment are discussed.
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Affiliation(s)
- Anthony M Lynch
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | - Jonathan Howe
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | | | - James S Harvey
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | - Mark Burman
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | - Danielle S G Harte
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | - Liangfu Chen
- DMPK, GSK R&D, Upper Providence, Collegeville, PA, United States
| | - Casey Kmett
- DMPK, GSK R&D, Upper Providence, Collegeville, PA, United States
| | - Wei Shi
- DMPK, GSK R&D, Upper Providence, Collegeville, PA, United States
| | - Charles F McHugh
- DMPK, GSK R&D, Upper Providence, Collegeville, PA, United States
| | - Kinnari K Patel
- BIB, GSK R&D, Upper Providence, Collegeville, PA, United States
| | | | - Julia Kenny
- TPPS, GSK R&D, Stevenage, SG1 2NY, United Kingdom
| | | | - John W Wills
- Genetic Toxicology & Photosafety, GSK R&D, Stevenage, SG1 2NY, United Kingdom
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Hall AP, Tepper JS, Boyle MH, Cary MG, Flandre TG, Piaia A, Tarnow I, Macri NP, Freke MC, Nikula KJ, Paul GR, Cauvin A, Gregori M, Haworth R, Naylor S, Price M, Robinson IN, Allen A, Gelzleichter T, Hohlbaum AM, Manetz S, Wolfreys A, Colman K, Fleurance R, Jones D, Mukaratirwa S. BSTP Review of 12 Case Studies Discussing the Challenges, Pathology, Immunogenicity, and Mechanisms of Inhaled Biologics. Toxicol Pathol 2021; 49:235-260. [PMID: 33455525 DOI: 10.1177/0192623320976094] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The inhalation route is a relatively novel drug delivery route for biotherapeutics and, as a result, there is a paucity of published data and experience within the toxicology/pathology community. In recent years, findings arising in toxicology studies with inhaled biologics have provoked concern and regulatory challenges due, in part, to the lack of understanding of the expected pathology, mechanisms, and adversity induced by this mode of delivery. In this manuscript, the authors describe 12 case studies, comprising 18 toxicology studies, using a range of inhaled biotherapeutics (monoclonal antibodies, fragment antigen-binding antibodies, domain antibodies, therapeutic proteins/peptides, and an oligonucleotide) in rodents, nonhuman primates (NHPs), and the rabbit in subacute (1 week) to chronic (26 weeks) toxicology studies. Analysis of the data revealed that many of these molecules were associated with a characteristic pattern of toxicity with high levels of immunogenicity. Microscopic changes in the airways consisted of a predominantly lymphoid perivascular/peribronchiolar (PV/PB) mononuclear inflammatory cell (MIC) infiltrate, whereas changes in the terminal airways/alveoli were characterized by simple ("uncomplicated") increases in macrophages or inflammatory cell infiltrates ranging from mixed inflammatory cell infiltration to inflammation. The PV/PB MIC changes were considered most likely secondary to immunogenicity, whereas simple increases in alveolar macrophages were most likely secondary to clearance mechanisms. Alveolar inflammatory cell infiltrates and inflammation were likely induced by immune modulation or stimulation through pharmacologic effects on target biology or type III hypersensitivity (immune complex disease). Finally, a group of experts provide introductory thoughts regarding the adversity of inhaled biotherapeutics and the basis for reasonable differences of opinion that might arise between toxicologists, pathologists, and regulators.
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Affiliation(s)
| | | | | | | | - Thierry G Flandre
- 98560Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Alessandro Piaia
- 98560Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | | | - Mark C Freke
- 70294Charles River Laboratories Montreal ULC, Senneville, Quebec, Canada
| | | | | | | | | | | | - Stuart Naylor
- Charles River Laboratories, Edinburgh, United Kingdom
| | - Mark Price
- 1929GlaxoSmithKline, Ware, United Kingdom
| | | | | | | | | | | | | | - Karyn Colman
- 70089Genomics Institute for the Novartis Research Foundation, San Diego, CA, USA
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3
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Haworth R, Boyle M, Edwards P, Gupta R, Fagg R, Karantabias G, Price M. Preclinical Safety Assessment of 2 Inhaled Single-Domain Antibodies in the Cynomolgus Monkey. Toxicol Pathol 2020; 49:296-314. [PMID: 33272097 DOI: 10.1177/0192623320972387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The safety of 2 single domain antibodies (dAbs) was evaluated by inhalation toxicology studies in the cynomolgus monkey. In the first case study, a 14-day repeat-dose study evaluating an anti-thymic stromal lymphopoietin (anti-TSLP) dAb resulted in minimal mononuclear inflammatory cell infiltrates in the lungs, increases in lymphocytes in bronchoalveolar lavage fluid, and development of antidrug antibodies (ADAs). In a 6-week inhalation study, there was an increase in incidence and/or severity of mononuclear cell infiltrates in the lung, increased cellularity in the tracheobronchial lymph node (TBLN), and development of ADA. The second case study evaluated a change in duration of inhalation dosing, a different route of exposure (intravenous or IV), and recovery following an off-dose period with an anti-tumor necrosis factor receptor 1 dAb. A 7-day repeat-dose inhalation study and a 14-day IV study produced no microscopic effects in the lung, whereas a 14-day inhalation study resulted in moderate increases in pulmonary perivascular/peribronchiolar/alveolar lymphocytic infiltrates and increased cellularity in the TBLN, with partial and full recovery, respectively, after 14 days. The lung and lymph node findings seen after inhalation of either dAb were considered secondary to the immunogenic response to a human protein and were considered nonadverse.
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Affiliation(s)
| | | | - Paul Edwards
- Covance, Woolley Road, Huntingdon, United Kingdom
| | - Reenu Gupta
- Covance, Woolley Road, Huntingdon, United Kingdom
| | - Rajni Fagg
- 114154GSK R&D, Park Road, Ware, United Kingdom
| | | | - Mark Price
- 114154GSK R&D, Park Road, Ware, United Kingdom
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Prior H, Haworth R, Labram B, Roberts R, Wolfreys A, Sewell F. Justification for species selection for pharmaceutical toxicity studies. Toxicol Res (Camb) 2020; 9:758-770. [PMID: 33442468 PMCID: PMC7786171 DOI: 10.1093/toxres/tfaa081] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 12/15/2022] Open
Abstract
Toxicity studies using mammalian species are generally required to provide safety data to support clinical development and licencing registration for potential new pharmaceuticals. International regulatory guidelines outline recommendations for the order (rodent and/or non-rodent) and number of species, retaining flexibility for development of a diverse range of drug modalities in a manner relevant for each specific new medicine. Selection of the appropriate toxicology species involves consideration of scientific, ethical and practical factors, with individual companies likely having different perspectives and preferences regarding weighting of various aspects dependent upon molecule characteristics and previous experience of specific targets or molecule classes. This article summarizes presentations from a symposium at the 2019 Annual Congress of the British Toxicology Society on the topic of species selection for pharmaceutical toxicity studies. This symposium included an overview of results from a National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) and Association of British Pharmaceutical Industry (ABPI) international collaboration that reviewed the use of one or two species in regulatory toxicology studies and justification for the species selected within each programme. Perspectives from two pharmaceutical companies described their processes for species selection for evaluation of biologics, and justification for selection of the minipig as a toxicological species for small molecules. This article summarizes discussions on the scientific justification and other considerations taken into account to ensure the most appropriate animal species are used for toxicity studies to meet regulatory requirements and to provide the most value for informing project decisions.
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Affiliation(s)
- Helen Prior
- National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), 215 Euston Rd, London, NW1 2BE, UK
| | | | - Briony Labram
- National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), 215 Euston Rd, London, NW1 2BE, UK
| | - Ruth Roberts
- ApconiX, Alderley Park, Alderley Edge, SK10 4TG, UK
| | | | - Fiona Sewell
- National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), 215 Euston Rd, London, NW1 2BE, UK
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5
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Haworth R, Sharpe M. Accept or Reject: The Role of Immune Tolerance in the Development of Stem Cell Therapies and Possible Future Approaches. Toxicol Pathol 2020; 49:1308-1316. [PMID: 32319357 DOI: 10.1177/0192623320918241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In 2011, Goldring and colleagues published a review article describing the potential safety issues of novel stem cell-derived treatments. Immunogenicity and immunotoxicity of the administered cell product were considered risks in the light of clinical experience of transplantation. The relative immunogenicity of mesenchymal stem cells, embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs) was being addressed through in vitro and in vivo models. But the question arose as to whether the implanted cells needed to be identical to the recipient in every respect, including epigenetically, to evade immune recognition? If so, this set a high bar which may preclude use of many cells derived from iPSCs which have vestiges of a fetal phenotype and epigenetic memory of their cell of origin. However, for autologous iPSCs, the immunogenicity reduces once the surface antigen expression profile becomes close to that of the parent somatic cells. Therefore, a cell product containing incompletely differentiated cells could be more immunogenic. The properties of the administered cells, the immune privilege of the administration site, and the host immune status influence graft success or failure. In addition, the various approaches available to characterize potential immunogenicity of a cell therapy will be discussed.
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6
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Abstract
Cautious approaches in the clinic are currently proposed, supported by relevant in vitro, in vivo and published data. Key to developing our understanding of the risks of immune rejection of stem cell based therapies will be the inclusion of immunological endpoints in clinical trials and the sharing of data. There is likely not a one-size-fits all strategy but one dependent on cell therapy, mode of action and disease indication.
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Affiliation(s)
- Richard Haworth
- Safety Assessment, GlaxoSmithKline R&D, Park Road, Ware, Herts., SG12 0DP, UK
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7
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Dixon D, Alison R, Bach U, Colman K, Foley GL, Harleman JH, Haworth R, Herbert R, Heuser A, Long G, Mirsky M, Regan K, Van Esch E, Westwood FR, Vidal J, Yoshida M. Nonproliferative and proliferative lesions of the rat and mouse female reproductive system. J Toxicol Pathol 2014; 27:1S-107S. [PMID: 25516636 PMCID: PMC4253081 DOI: 10.1293/tox.27.1s] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicological Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in the female reproductive tract of laboratory rats and mice, with color photomicrographs illustrating examples of some lesions. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and aging lesions as well as lesions induced by exposure to test materials. There is also a section on normal cyclical changes observed in the ovary, uterus, cervix and vagina to compare normal physiological changes with pathological lesions. A widely accepted and utilized international harmonization of nomenclature for female reproductive tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.
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Affiliation(s)
- Darlene Dixon
- National Institute of Environmental Health Sciences, National
Toxicology Program, Research Triangle Park, North Carolina, USA
| | - Roger Alison
- Roger Alison Ltd, Pathology Consultancy Services, Caerfyrddin
Fach, Cilcennin, Lampeter, SA48 8RN, United Kingdom
| | - Ute Bach
- Bayer Pharma AG, Wuppertal, Germany
| | - Karyn Colman
- Novartis Institute for Biomedical Research, Novartis, East
Hanover, New Jersey, USA
| | | | | | - Richard Haworth
- GlaxoSmithKline R&D, Park Road, Ware, Hertfordshire, SG12
ODP, United Kingdom
| | - Ronald Herbert
- National Institute of Environmental Health Sciences, National
Toxicology Program, Research Triangle Park, North Carolina, USA
| | - Anke Heuser
- Roche Pharma Research and Early Development, Roche Innovation
Center Basel, Grenzacher Strasse 124, 4070 Basel, Switzerland
| | - Gerald Long
- Experimental Pathology Laboratories, Indianapolis, Indiana,
USA
| | - Michael Mirsky
- Pfizer Worldwide Research and Development, Groton,
Connecticut, USA
| | | | - Eric Van Esch
- InSight Pathology BV, Chopinlaan 6, Oss, The
Netherlands
| | | | - Justin Vidal
- GlaxoSmithKline, King of Prussia, Pennsylvania, USA
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8
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Frazier KS, Sobry C, Derr V, Adams MJ, Besten CD, De Kimpe S, Francis I, Gales TL, Haworth R, Maguire SR, Mirabile RC, Mullins D, Palate B, Doorten YPS, Ridings JE, Scicchitano MS, Silvano J, Woodfine J. Species-specific inflammatory responses as a primary component for the development of glomerular lesions in mice and monkeys following chronic administration of a second-generation antisense oligonucleotide. Toxicol Pathol 2013; 42:923-35. [PMID: 24292388 DOI: 10.1177/0192623313505781] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Chronic administration of drisapersen, a 2'-OMe phosphorothioate antisense oligonucleotide (AON) to mice and monkeys resulted in renal tubular accumulation, with secondary tubular degeneration. Glomerulopathy occurred in both species with species-specific characteristics. Glomerular lesions in mice were characterized by progressive hyaline matrix accumulation, accompanied by the presence of renal amyloid and with subsequent papillary necrosis. Early changes involved glomerular endothelial hypertrophy and degeneration, but the chronic glomerular amyloid and hyaline alterations in mice appeared to be species specific. An immune-mediated mechanism for the glomerular lesions in mice was supported by early inflammatory changes including increased expression of inflammatory cytokines and other immunomodulatory genes within the renal cortex, increased stimulation of CD68 protein, and systemic elevation of monocyte chemotactic protein 1. In contrast, kidneys from monkeys given drisapersen chronically showed less severe glomerular changes characterized by increased mesangial and inflammatory cells, endothelial cell hypertrophy, and subepithelial and membranous electron-dense deposits, with ultrastructural and immunohistochemical characteristics of complement and complement-related fragments. Lesions in monkeys resembled typical features of C3 glomerulopathy, a condition described in man and experimental animals to be linked to dysregulation of the alternative complement pathway. Thus, inflammatory/immune mechanisms appear critical to glomerular injury with species-specific sensitivities for mouse and monkey. The lower observed proinflammatory activity in humans as compared to mice and monkeys may reflect a lower risk of glomerular injury in patients receiving AON therapy.
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Affiliation(s)
- Kendall S Frazier
- Department of Safety Assessment, GlaxoSmithKline, King of Prussia, Pennsylvania, USA
| | | | - Victoria Derr
- Pathology, Microbiology and Immunology, University of California-Davis, California, USA
| | - Mike J Adams
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
| | | | | | - Ian Francis
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
| | - Tracy L Gales
- Department of Safety Assessment, GlaxoSmithKline, King of Prussia, Pennsylvania, USA
| | - Richard Haworth
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
| | - Shaun R Maguire
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
| | - Rosanna C Mirabile
- Department of Safety Assessment, GlaxoSmithKline, King of Prussia, Pennsylvania, USA
| | - David Mullins
- Department of Safety Assessment, GlaxoSmithKline, King of Prussia, Pennsylvania, USA
| | | | | | - James E Ridings
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
| | | | | | - Jennie Woodfine
- Departments of Safety Assessment and Scinovo, GlaxoSmithKline, Ware, United Kingdom
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Haworth R, Woodfine J, McCawley S, Pilling AM, Lewis DJ, Williams TC. Pulmonary neuroendocrine cell hyperplasia: identification, diagnostic criteria and incidence in untreated ageing rats of different strains. Toxicol Pathol 2007; 35:735-40. [PMID: 17849355 DOI: 10.1080/01926230701460000] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [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: 10/22/2022]
Abstract
Pulmonary Neuroendocrine Cells (PNEC) are found as clusters called neuroepithelial bodies (NEB) or as single cells scattered in the respiratory epithelium. Pulmonary neuroendocrine cell hyperplasia is recorded in humans and experimentally manipulated rodents. The objectives of this work were to identify the optimal immunohistochemical markers for PNEC in the rat for use on paraffin-embedded, formalin-fixed material and to provide the first comparative incidence of PNEC hyperplasia in untreated 2-year-old rats of different strains. Calcitonin-gene related peptide (CGRP) and protein G product 9.5 (PGP9.5) antibodies identified PNEC consistently and selectively. In contrast, PNEC did not express chromogranin-A or S-100. PNEC hyperplasia was defined as foci of PNEC with greater than 40 nuclei, excluding overlying respiratory epithelium and submucosal PNEC. PNEC hyperplasia was observed at low incidence (0-7%) in untreated 2-year-old Sprague-Dawley, Han Wistar and Wistar rats but not Fischer 344 rats. This is the first report of spontaneous PNEC hyperplasia in rats. The cause of this hyperplasia is unknown, but experimental models that induce PNEC hyperplasia by causing bronchiolar cell injury are discussed. PNEC neoplasia in the rat is unreported in the literature and was not observed in animals examined in this study.
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Affiliation(s)
- Richard Haworth
- Department of Pathology, Safety Asssessment, GlaxoSmithKline Research and Development Ltd, Herts, United Kingdom.
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10
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Dincer Z, Jones S, Haworth R. Preclinical safety assessment of a DNA vaccine using particle-mediated epidermal delivery in domestic pig, minipig and mouse. ACTA ACUST UNITED AC 2006; 57:351-7. [PMID: 16713213 DOI: 10.1016/j.etp.2006.03.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 03/30/2006] [Indexed: 11/22/2022]
Abstract
DNA vaccination involves the direct injection of genes coding for specific antigenic proteins. One technique known as particle-mediated epidermal delivery (PMED) is a practical approach for epidermal delivery and provides a strong immune response. An important aspect of the preclinical safety assessment of DNA vaccines is the selection of a pharmacologically relevant animal model for the assessment of antigen expression, optimization of delivery and formulation of the plasmid. This paper describes a comparative study of domestic pig, minipig and mouse in regard to local tolerance and antigen expression of HIV immunotherapeutic using PMED. Pig/minipig is considered a good model for the safety assessment of DNA vaccines due to the similarity to human skin. Local reactions were evaluated at 10 min, 4, 24 and 48 h. Histology of administration sites revealed epidermal necrosis with associated dermal inflammation at 10 min and 4h, and subsequent regeneration with repair at 24 and 48 h. The degree and extent of these changes varied according to species. Domestic pig and minipig showed superficial epidermal necrosis and complete repair, while the mouse showed full-thickness epidermal necrosis and partial repair. Expression of HIV antigen was confirmed using immunohistochemistry in all three species at 4, 24 and 48 h. The results showed that PMED is an effective system for DNA vaccine delivery as demonstrated by the antigen expression seen as early as 4 h.
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MESH Headings
- AIDS Vaccines/administration & dosage
- AIDS Vaccines/adverse effects
- AIDS Vaccines/pharmacokinetics
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/adverse effects
- Adjuvants, Immunologic/pharmacokinetics
- Animals
- Biolistics
- DNA, Viral/chemistry
- DNA, Viral/immunology
- DNA, Viral/toxicity
- Drug Evaluation, Preclinical
- Epidermis/drug effects
- Epidermis/pathology
- Female
- Gold/chemistry
- Gold/immunology
- Gold/pharmacokinetics
- HIV Antibodies/biosynthesis
- Keratinocytes/drug effects
- Keratinocytes/pathology
- Keratinocytes/virology
- Male
- Mice
- Mice, Inbred BALB C
- Regeneration/drug effects
- Skin/drug effects
- Skin/pathology
- Skin/virology
- Species Specificity
- Swine
- Swine, Miniature
- Vaccination
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/adverse effects
- Vaccines, DNA/pharmacokinetics
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Affiliation(s)
- Zuhal Dincer
- GlaxoSmithKline, R&D, Safety Assessment, Department of Pathology, The Frythe, Welwyn, Hertfordshire AL6 9AR, UK.
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11
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Haworth R, McCormack N, Selway S, Pilling AM, Williams TC. Calbindin D-28 and microtubule-associated protein-2: their use as sensitive immunohistochemical markers of cerebellar neurotoxicity in a regulatory toxicity study. ACTA ACUST UNITED AC 2006; 57:419-26. [PMID: 16542831 DOI: 10.1016/j.etp.2006.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2005] [Accepted: 01/01/2006] [Indexed: 11/19/2022]
Abstract
The aim of this study was to develop an immunohistochemical (IHC) method for calbindin D-28 (CB-28) and microtubule-associated protein-2 (MAP-2) and evaluate their expression as markers in the detection, characterisation and grading of unexpected cerebellar toxicity in the rat. High power examination of H&E-stained brain sections of treated rats 2 days following a single oral dose of a novel compound revealed irregular vacuolation of the molecular layer and Purkinje cell degeneration. Animals killed after 14 days recovery showed Purkinje cell degeneration but vacuolation of the molecular layer was absent. In control animals, CB-28 and MAP-2 expression was high in Purkinje cell dendrites and cell bodies in the molecular layer. In treated animals, low power examination revealed loss of CB-28 and MAP-2 expression in degenerating neurons arranged in parasagittal stripes within the vermis. This is the first description of successful use of these two markers in a regulatory toxicity study using FFPE brain. In particular, CB-28 provides a sensitive method for characterising CNS toxicity which can be detected at low power enabling easier detection, screening and grading of neurotoxicity.
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Affiliation(s)
- Richard Haworth
- Department of Pathology, Safety Asssessment, GlaxoSmithKline Research and Development Ltd, Park Road, Ware, Herts SG12 0DP, UK.
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12
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Abstract
The aim of this study was to use immunohistochemistry with morphometry to investigate COX-1 and COX-2 expression in the normal rat gastrointestinal (GI) tract and examine if sites of ulceration previously observed with long-term COX-2 inhibitor administration in mice correlate with differential COX-1/COX-2 expression. COX-2 positive cells were observed predominantly in the apical lamina propria of intestinal villi with fewer cells in the mucosal epithelium. The highest level of COX-2 expression was observed at the ileocaecal junction (ICJ). COX-2 expression was also present in parasympathetic ganglia of the submucosa and muscularis. In the stomach, the highest grade of COX-2 expression was observed in the apical lamina propria of the fundus adjacent to the junctional ridge. In contrast, COX-1 positive cells within the lamina propria were evenly distributed along the GI tract but were present in higher numbers than COX-2 positive cells. The mean level of COX-1 expression at the ICJ was not significantly different from the ileum and caecum. Evidence that the highest level of COX-2 expression in normal rats is located on the ileal side of the ICJ provides the first mechanism to explain spontaneous ulceration and perforation of the distal ileum in COX-2 -/- animals.
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Affiliation(s)
- Richard Haworth
- Department of Pathology, Safety Assessment, GlaxoSmithKline Research and Development Ltd., Ware, Herts SG12 0DP, United Kingdom.
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13
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Richardson JC, Kendal CE, Anderson R, Priest F, Gower E, Soden P, Gray R, Topps S, Howlett DR, Lavender D, Clarke NJ, Barnes JC, Haworth R, Stewart MG, Rupniak HTR. Ultrastructural and behavioural changes precede amyloid deposition in a transgenic model of Alzheimer’s disease. Neuroscience 2003; 122:213-28. [PMID: 14596862 DOI: 10.1016/s0306-4522(03)00389-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [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: 10/26/2022]
Abstract
We describe the thorough characterisation of a new transgenic mouse line overexpressing the 695-amino acid isoform of human amyloid precursor protein harbouring the Swedish double familial Alzheimer's disease mutation. This line, referred to as TAS10, exhibits neuropathological features and cognitive deficits that are closely correlated to the accumulation of Abeta in their brain and that are reminiscent of those observed in AD. Data on the TAS10 line are presented at five time points: 2, 6, 12, 18 and 24 months in a longitudinal study. The TAS10 line is characterised by the following changes: i) significant age-related increases in the levels of total and individual species (1-40, 1-42) of beta-amyloid in the brains of transgenics compared with non-transgenic littermates; ii) transgenic mice showed pronounced spatial learning deficits in the Morris water maze at 6 months and working memory deficits by 12 months; iii) amyloid plaque and associated pathologies were observed by the 12-month time point and the burden increased substantially, particularly in the cortex, by 18 months; iv) electron microscopy of the hippocampus of transgenic mice showed evidence of abnormal ultrastructural features such as dystrophic neurites and lipid deposits that developed from 6 months and increased in number and severity with age. Morphometric studies demonstrate that the synapse to neuron ratio is higher in transgenics than in control mice at 12 months, but this ratio decreases as they age and synapse size increases. Thus, this mouse model exhibits a close correlation of amyloid burden with behavioural deficits and ultrastructural abnormalities and so represents an ideal system to study the mechanisms underlying the impact of amyloid pathology on CNS function.
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Affiliation(s)
- J C Richardson
- Neurology Centre of Excellence for Drug Discovery, GlaxoSmithKline, New Frontiers Science Park, Third Avenue, Harlow, Essex, CM19 5AW UK.
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14
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Sanchez-Morgado JM, Haworth R, Morris TH. XY female marmoset (Callithrix jacchus). Comp Med 2003; 53:539-44. [PMID: 14655998] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
A marmoset (Callithrix jacchus) with atypical external genitalia was phenotypically and genetically characterized. Testosterone concentration correlated with that of female marmosets. Externally, there was only one opening for the urethra. Internal genitalia were characteristic of those of female marmosets, and consisted of ovaries, with follicles in various developmental stages, and uterus. Microscopically, a normal vaginal structure was found. An XX/XY chimerism and high steroid hormone values are normally found in common marmosets. Genetic analysis was used for in vivo determination of sex. The Y-linked zinc finger protein gene (ZFY) last intron, and sex-determining region Y gene (SRY) exon were found by use of polymerase chain reaction and posterior sequencing analyses, indicating that this marmoset had Y-linked chromosome sequences. Normal SRY exons can, therefore, be associated with female internal sexual organs in marmosets; this may be the first XY female described in non-human primates.
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Affiliation(s)
- Jose M Sanchez-Morgado
- Laboratory Animal Science, GlaxoSmithkline, The Frythe, Welwyn, Herts, AL6 9AR, United Kingdom
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15
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Affiliation(s)
- R Haworth
- Molecular Pathology Group, Safety Assessment, GlaxoSmithKline Research and Development, Park Road, Ware, Hertfordshire SG12 0DP
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16
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Abstract
The class A macrophage scavenger receptor (SR-A) is the prototypic example of a group of plasma membrane receptors collectively known as scavenger receptors. SR-A displays the ability to bind and endocytose large quantities of modified lipoprotein. Hence, it is thought to be one of the main receptors involved in mediating lipid influx into macrophages (Mphi), which promotes their conversion into foam cells that are abundant in the atherosclerotic lesion. However, as a result of increased interest and research effort and through the development of specific reagents and animal models, it is now appreciated to be multifunctional. These roles include Mphi growth and maintenance, adhesion to the substratum, cell-cell interactions, phagocytosis, and host defense. In this review, we attempt to summarize the evidence and argue that these kinds of activities underlie the biological versatility of Mphi.
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Affiliation(s)
- Nick Platt
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
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17
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Pilling AM, Harman RM, Jones SA, McCormack NAM, Lavender D, Haworth R. The assessment of local tolerance, acute toxicity, and DNA biodistribution following particle-mediated delivery of a DNA vaccine to minipigs. Toxicol Pathol 2002; 30:298-305. [PMID: 12051546 DOI: 10.1080/01926230252929864] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [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: 10/16/2022]
Abstract
Particle-mediated DNA delivery was used to administer a DNA vaccine against Hepatitis B to minipigs. The study represented one arm of the safety evaluation program for this product and was designed to assess local tolerance, acute toxicity, and biodistribution of the DNA plasmid. The vaccine was given to 4 groups of minipigs that were sacrificed at 2, 28, 56, or 141 days after treatment. The procedure was well tolerated with mild local skin reactions at 2 days postdosing and no evidence of systemic toxicity. By 28 days the skin lesions had regressed apart from a low grade perivascular mononuclear cell infiltrate in the upper dermis, together with a small number of phagocytosed gold particles. This infiltrate persisted up to 141 days. The expressed HBsAg was detected by immunohistochemistry in keratinocytes (usually in association with an intranuclear gold particle) at 2 days but not at later time points. Polymerase chain reaction (PCR) was used to assay treatment sites and selected internal organs to evaluate biodistribution and persistence of the DNA plasmid. At 2 days the plasmid was detected in the treatment sites and also in the inguinal lymph nodes. At day 57 it was present in the treatment sites only and by day 141 appeared to have cleared. The results from this study demonstrate that particle-mediated gene delivery was well tolerated in the minipig. The biodistribution and persistence of the plasmid was within acceptable limits for this type of vaccine. As the minipig is regarded as a good model for humans these data support the concept that particle-mediated DNA delivery will be safe in human clinical applications.
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Affiliation(s)
- Andrew M Pilling
- Pathology Department, Safety Assessment, GlaxoSmithKline, Ware, Hertfordshire, United Kingdom.
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18
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Peiser L, Gordon S, Haworth R. Isolation of and measuring the function of professional phagocytes: Murine macrophages. Immunology of Infection 2002. [DOI: 10.1016/s0580-9517(02)32098-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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19
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Abstract
The polymerase chain reaction (PCR) is a highly efficient gene amplification procedure which is increasingly being applied to the safety assessment of nucleic acid (NA) medicines such as gene therapies and DNA vaccines. Although clinical experience is limited, a number of potential safety issues exist with these new compounds including toxicity associated with the expression of encoded gene products, autoimmunity due to the induction of anti-DNA antibodies and insertional mutagenesis. PCR enables these questions to be addressed and provides data on mRNA expression, biodistribution and integration. In this review the use of PCR methodologies in the preclinical safety evaluation of NA medicines is discussed. Particular consideration is given to the issues surrounding the use of PCR in regulatory toxicology, including sensitivity requirements, cross-contamination problems, tissue sampling procedures and good laboratory practice (GLP) compliance. In addition, the use of a PCR-based assay to demonstrate the integration of DNA vector into host DNA is described. As the use of PCR in the development of NA medicines will undoubtedly increase over the next few years, it is important that pathologists and toxicologists familiarise themselves with the principles and applications of this technique.
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Affiliation(s)
- R Haworth
- Molecular Pathology Group, Medicines Safety Evaluation Division, Glaxo Wellcome Research and Development Ltd., Park Road, Ware, Hertfordshire SG12 0DP, UK
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20
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van der Laan LJW, Döpp EA, Haworth R, Pikkarainen T, Kangas M, Elomaa O, Dijkstra CD, Gordon S, Tryggvason K, Kraal G. Regulation and Functional Involvement of Macrophage Scavenger Receptor MARCO in Clearance of Bacteria In Vivo. The Journal of Immunology 1999. [DOI: 10.4049/jimmunol.162.2.939] [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
The scavenger receptors expressed by macrophages are thought to play an important role in the immune response against bacteria by mediating binding and phagocytosis. A novel member of the class A scavenger receptor family, macrophage receptor with collagenous structure (MARCO), has recently been identified. In this study we have generated a panel of mAbs with specificities for different domains of this receptor. Two of those reacting with the C-terminal cysteine-rich domain block ligand binding of MARCO. The in vivo expression of this murine receptor is normally restricted to distinct populations of macrophages in the spleen and lymph nodes. During bacillus Calmette-Guérin (BCG) infection, during bacterial sepsis, or after the injection of purified LPS, however, the expression of MARCO is rapidly induced on macrophages in other tissues, including Kupffer cells in the liver. Using the mouse macrophage cell line J774.2, it was shown that LPS stimulation up-regulates surface expression of MARCO in a dose- and time-dependent fashion. The proinflammatory cytokines IL-1, IL-6, TNF-α, and IFN-γ had little or no effect. Using inhibitory mAbs, the relevance of MARCO for the clearance of circulating bacteria in vivo was determined. Although the overall elimination of live Escherichia coli and Staphylococcus aureus from the blood did not appear to be affected by treatment with these Abs, the capturing of heat-killed bacteria by macrophages in the marginal zone areas of the spleen was clearly inhibited. This study suggests a role for MARCO in the host antibacterial defense.
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Affiliation(s)
- Luc J. W. van der Laan
- *Department of Cell Biology and Immunology, Vrije Universiteit, Amsterdam, The Netherlands
| | - Ed A. Döpp
- *Department of Cell Biology and Immunology, Vrije Universiteit, Amsterdam, The Netherlands
| | - Richard Haworth
- †Sir William Dunn School of Pathology, Oxford, United Kingdom; and
| | - Timo Pikkarainen
- ‡Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Maarit Kangas
- ‡Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Outi Elomaa
- ‡Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Christine D. Dijkstra
- *Department of Cell Biology and Immunology, Vrije Universiteit, Amsterdam, The Netherlands
| | - Siamon Gordon
- †Sir William Dunn School of Pathology, Oxford, United Kingdom; and
| | - Karl Tryggvason
- ‡Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Georg Kraal
- *Department of Cell Biology and Immunology, Vrije Universiteit, Amsterdam, The Netherlands
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21
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van der Laan LJ, Döpp EA, Haworth R, Pikkarainen T, Kangas M, Elomaa O, Dijkstra CD, Gordon S, Tryggvason K, Kraal G. Regulation and functional involvement of macrophage scavenger receptor MARCO in clearance of bacteria in vivo. J Immunol 1999; 162:939-47. [PMID: 9916718] [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: 02/10/2023]
Abstract
The scavenger receptors expressed by macrophages are thought to play an important role in the immune response against bacteria by mediating binding and phagocytosis. A novel member of the class A scavenger receptor family, macrophage receptor with collagenous structure (MARCO), has recently been identified. In this study we have generated a panel of mAbs with specificities for different domains of this receptor. Two of those reacting with the C-terminal cysteine-rich domain block ligand binding of MARCO. The in vivo expression of this murine receptor is normally restricted to distinct populations of macrophages in the spleen and lymph nodes. During bacillus Calmette-Guérin (BCG) infection, during bacterial sepsis, or after the injection of purified LPS, however, the expression of MARCO is rapidly induced on macrophages in other tissues, including Kupffer cells in the liver. Using the mouse macrophage cell line J774.2, it was shown that LPS stimulation up-regulates surface expression of MARCO in a dose- and time-dependent fashion. The proinflammatory cytokines IL-1, IL-6, TNF-alpha, and IFN-gamma had little or no effect. Using inhibitory mAbs, the relevance of MARCO for the clearance of circulating bacteria in vivo was determined. Although the overall elimination of live Escherichia coli and Staphylococcus aureus from the blood did not appear to be affected by treatment with these Abs, the capturing of heat-killed bacteria by macrophages in the marginal zone areas of the spleen was clearly inhibited. This study suggests a role for MARCO in the host antibacterial defense.
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Affiliation(s)
- L J van der Laan
- Department of Cell Biology and Immunology, Vrije Universiteit, Amsterdam, The Netherlands
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22
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Haworth R, Platt N, Keshav S, Hughes D, Darley E, Suzuki H, Kurihara Y, Kodama T, Gordon S. The macrophage scavenger receptor type A is expressed by activated macrophages and protects the host against lethal endotoxic shock. J Exp Med 1997; 186:1431-9. [PMID: 9348300 PMCID: PMC2199123 DOI: 10.1084/jem.186.9.1431] [Citation(s) in RCA: 228] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/1997] [Revised: 07/11/1997] [Indexed: 02/05/2023] Open
Abstract
During gram-negative bacterial infections, lipopolysaccharide (LPS) stimulates primed macrophages (Mphi) to release inflammatory mediators such as tumor necrosis factor (TNF)-alpha, which can cause hypotension, organ failure, and often death. Several different receptors on Mphi have been shown to bind LPS, including the type A scavenger receptor (SR-A). This receptor is able to bind a broad range of polyanionic ligands such as modified lipoproteins and lipoteichoic acid of gram-positive bacteria, which suggests that SR-A plays a role in host defense. In this study, we used mice lacking the SR-A (SRKO) to investigate the role of SR-A in acquired immunity using a viable bacillus Calmette Guérin (BCG) infection model. We show that activated Mphi express SR-A and that this molecule is functional in assays of adhesion and endocytic uptake. After BCG infection, SRKO mice are able to recruit Mphi to sites of granuloma formation where they become activated and restrict BCG replication. However, infected mice lacking the SR-A are more susceptible to endotoxic shock and produce more TNF-alpha and interleukin-6 in response to LPS. In addition, we show that an antibody which blocks TNF-alpha activity reduces LPS-induced mortality in these mice. Thus SR-A, expressed by activated Mphi, plays a protective role in host defense by scavenging LPS as well as by reducing the release by activated Mphi of proinflammatory cytokines. Modulation of SR-A may provide a novel therapeutic approach to control endotoxic shock.
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MESH Headings
- Animals
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/pharmacology
- Cell Movement/immunology
- Cytokines/biosynthesis
- Disease Models, Animal
- Female
- Granuloma/immunology
- Injections, Intraperitoneal
- Lipopolysaccharides/toxicity
- Macrophage Activation/drug effects
- Macrophages, Peritoneal/drug effects
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Male
- Mice
- Mice, Inbred ICR
- Mice, Knockout
- Mycobacterium bovis/immunology
- Receptors, Immunologic/biosynthesis
- Receptors, Immunologic/physiology
- Receptors, Scavenger
- Scavenger Receptors, Class A
- Shock, Septic/immunology
- Shock, Septic/mortality
- Shock, Septic/prevention & control
- Tuberculosis/immunology
- Tumor Necrosis Factor-alpha/immunology
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Affiliation(s)
- R Haworth
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
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23
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Wearden JH, Denovan L, Fakhri M, Haworth R. Scalar timing in temporal generalization in humans with longer stimulus durations. J Exp Psychol Anim Behav Process 1997; 23:502-11. [PMID: 9335137 DOI: 10.1037/0097-7403.23.4.502] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Three experiments investigated temporal generalization performance in humans by using stimulus durations similar to those previously used with rats. In most conditions, chronometric counting was prevented by concurrent shadowing of temporally irregular numbers. Experiment 1 examined performance with visual stimuli, when the standard was 4.0 s long and nonstandard stimuli were spaced either linearly or logarithmically around the standard. Generalization gradients were asymmetrical with linear spacing but symmetrical with logarithmic spacing, a result obtained previously with humans. Experiment 2 used auditory stimuli and varied the standard across values of 2.0, 4.0, 6.0, and 8.0 s. All gradients were asymmetrical, and good superposition was obtained, indicating conformity to scalar timing. Experiment 3 prevented or encouraged chronometric counting by changing instructions, and temporal generalization gradients differed when counting was and was not used.
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Affiliation(s)
- J H Wearden
- Department of Psychology, University of Manchester, United Kingdom.
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24
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Wang H, Silva NL, Lucchesi PA, Haworth R, Wang K, Michalak M, Pelech S, Fliegel L. Phosphorylation and regulation of the Na+/H+ exchanger through mitogen-activated protein kinase. Biochemistry 1997; 36:9151-8. [PMID: 9230047 DOI: 10.1021/bi970802f] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [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: 02/04/2023]
Abstract
We examined mitogen-activated protein kinase-mediated phosphorylation and activation of the Na+/H+ exchanger isoform type 1. A rabbit skeletal muscle extract was fractionated by FPLC chromatography. Four main fractions had the ability to phosphorylate the carboxyl-terminal region of NHE1. Western blot analysis and immunoprecipitation showed that three of these were associated with MAP kinase-dependent phosphorylation. Phosphorylation studies using purified MAP kinase showed that the region involved was the carboxyl-terminal 178 amino acids of the protein and that the stoichiometry was 1 phosphate/mol of protein. In-gel kinase assays showed that cytosolic extracts from smooth muscle cells also phosphorylate the carboxyl-terminal of NHE1 and that the MAP kinase-dependent phosphorylation could be activated by PDGF and AngII. Mutant cell lines with an inducible dominant negative MAP kinase showed decreased serum activation of Na+/H+ exchange but normal hypertonic activation of the protein. The results show that MAP kinase is intimately involved in regulation of the Na+/H+ exchanger, possibly through phosphorylation of one amino acid of the carboxyl-terminal cytosolic domain.
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Affiliation(s)
- H Wang
- Departments of Biochemistry and Pediatrics, University of Alberta, Edmonton, Canada
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25
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Munshi IA, Haworth R, Barie PS. Resolution of refractory pancreatic ascites after continuous infusion of octreotide acetate. Int J Pancreatol 1995; 17:203-6. [PMID: 7622943 DOI: 10.1007/bf02788540] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The treatment of pancreatic ascites remains a clinical challenge. Both medical and surgical management have high rates of mortality and recurrence. New methods in the treatment of pancreatic ascites are actively sought. We describe the successful use of a continuous infusion of octreotide acetate in the treatment of refractory alcoholic pancreatic ascites.
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Affiliation(s)
- I A Munshi
- Department of Surgery, New York Hospital-Cornell Medical Center, NY 10021, USA
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26
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Abstract
Adolescence is an important period in the development of adult sexual offending against women, yet it has received little attention in research on attitudes toward women and rape. The present study used the Attitudes Toward Women Scale (AWS) and Burt's (1980) Rape Myth Acceptance Scale (BRMAS) to compare the attitudes of 31 male adolescents convicted of sexual assaults on women (rape, attempted rape, indecent assault) with the attitudes of 27 male adolescents convicted of nonsexual violent crimes. The results showed no significant difference between the two groups on either measure. Furthermore, a more traditional, conservative attitude toward women, as measured on the AWS, did not significantly correlate with the endorsement of rape myths as measured on the BRMAS. The findings are discussed with reference to the validity and reliability of these measures when used with adolescents.
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Affiliation(s)
- K J Epps
- Department of Psychology, Glenthorne Centre (Youth Treatment Service), England
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27
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Carson J, Norris G, Haworth R. The difficult patient. Practitioner 1993; 237:313-9. [PMID: 8351271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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29
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Abstract
The results of a follow-up survey of 124 patients fitted with mobile arm supports at Mary Marlborough Lodge between 1970 and 1976 are presented. Of the patients fitted with mobile arm supports 33% are known to have used them for over one year, and 47% of those who were contacted were still using them. The reasons for non-use and the implications of the necessity for readjustments are discussed.
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30
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Abstract
Conditions are described under which crystals are formed with the ATPase enzyme from beef heart mitochondria. Enzyme activity is retained during the crystallization process. Some unit cell parameters have been determined by electron microscopy of negatively stained crystals; comparison with the unit cell crystalline matris inclusions indicates that such inclusions could be ATPase crystals.
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31
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32
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Haworth R. Mark Akenside, 1721-70. Br Med J 1970; 2:722-4. [PMID: 4914048 PMCID: PMC1700669 DOI: 10.1136/bmj.2.5711.722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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