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Raibeemol KP, Chitra KC. Induction of immunological, hormonal and histological alterations after sublethal exposure of chlorpyrifos in the freshwater fish, Pseudetroplus maculatus (Bloch, 1795). FISH & SHELLFISH IMMUNOLOGY 2020; 102:1-12. [PMID: 32278836 DOI: 10.1016/j.fsi.2020.04.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/29/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
The present study investigated the induction of immunological, hormonal and histological changes in the freshwater fish, Pseudetroplus maculatus after sublethal exposure of chlorpyrifos. Fish were exposed to chlorpyrifos at one-tenth (0.661μg/L) and one-fifth (1.32 μg/L) of LC50 value, for 15 and 30 d, along with the respective control group. Innate and adaptive immune responses of the fish against the toxicant exposure were measured using lysozyme, complement (ACH50) levels, phagocytic, nitroblue tetrazolium (NBT), myeloperoxidase (MPO), anti-protease and hemagglutination activities, and IgM concentration. The results revealed that sublethal exposure of chlorpyrifos caused significant (p < 0.05) reduction in lysozyme, ACH50, phagocytic, and anti-protease activities whereas there was significant (p < 0.05) increase in NBT, MPO and hemagglutination levels along with serum IgM concentration. Chlorpyrifos treatment showed significant (p < 0.05) decline in the serum levels of cortisol, thyroid, testosterone and estradiol hormones in duration- and concentration-dependent manner. The major histological lesions noted in liver includes necrosis, vacuolization, hepatocytic and cytoplasmic degeneration, while kidneys showed vacoules, necrosis and rupture in renal tubules and glomerulus, whereas spleen were found with melanomacrophage aggregation and necrosis. Similarly, testis showed remarkable changes like reduction in the number of spermatozoa and disintegrated seminiferous tubules while ovarian lesions include degenerated and empty follicles, few atretic oocytes, reduced size of follicles, and broken theca granulosa. The current findings revealed that the use of chlorpyrifos in domestic and agricultural purposes even at sublethal concentration could affect the non-target organisms including fish, and thereby alter the health status of aquatic ecosystems.
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Affiliation(s)
- K P Raibeemol
- Endocrinology and Toxicology Laboratory, Department of Zoology, University of Calicut, Malappuram District, Kerala, 673 635, India
| | - K C Chitra
- Endocrinology and Toxicology Laboratory, Department of Zoology, University of Calicut, Malappuram District, Kerala, 673 635, India.
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2
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Willard-Mack CL, Elmore SA, Hall WC, Harleman J, Kuper CF, Losco P, Rehg JE, Rühl-Fehlert C, Ward JM, Weinstock D, Bradley A, Hosokawa S, Pearse G, Mahler BW, Herbert RA, Keenan CM. Nonproliferative and Proliferative Lesions of the Rat and Mouse Hematolymphoid System. Toxicol Pathol 2020; 47:665-783. [PMID: 31526133 DOI: 10.1177/0192623319867053] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The INHAND Project (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative changes in rats and mice. The purpose of this publication is to provide a standardized nomenclature for classifying changes observed in the hematolymphoid organs, including the bone marrow, thymus, spleen, lymph nodes, mucosa-associated lymphoid tissues, and other lymphoid tissues (serosa-associated lymphoid clusters and tertiary lymphoid structures) with color photomicrographs illustrating examples of the lesions. Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. The nomenclature for these organs is divided into 3 terminologies: descriptive, conventional, and enhanced. Three terms are listed for each diagnosis. The rationale for this approach and guidance for its application to toxicologic pathology are described in detail below.
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Affiliation(s)
| | - Susan A Elmore
- Thymus subgroup lead.,National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | - Johannes Harleman
- Lymph node subgroup lead.,Neoplasm subgroup leads.,Independent Consultant, Darmstadt, Germany
| | - C Frieke Kuper
- Associated lymphoid organs subgroup lead.,Independent Consultant, Utrecht, the Netherlands
| | - Patricia Losco
- General hematolymphoid subgroup lead.,Independent Consultant, West Chester, PA, USA
| | - Jerold E Rehg
- Spleen subgroup leads.,Neoplasm subgroup leads.,Saint Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Jerrold M Ward
- Spleen subgroup leads.,Neoplasm subgroup leads.,Global VetPathology, Montgomery Village, MD, USA
| | | | - Alys Bradley
- Charles River Laboratories, Tranent, Scotland, United Kingdom
| | - Satoru Hosokawa
- Eisai Co, Ltd, Drug Safety Research Laboratories, Ibaraki, Japan
| | | | - Beth W Mahler
- Experimental Pathology Laboratories, Research Triangle Park, NC, USA
| | - Ronald A Herbert
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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3
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Baldrick P. Nonclinical Immunotoxicity Testing in the Pharmaceutical World: The Past, Present, and Future. Ther Innov Regul Sci 2019:2168479019864555. [PMID: 31409131 DOI: 10.1177/2168479019864555] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An examination for potential direct or indirect adverse effects on the immune system (immunotoxicity) is an established component of nonclinical testing to support safe use of new drugs. Testing recommendations occur in various regulatory guidance documents, especially ICH S8, and these will be presented. Key evaluation usually occurs in toxicology studies with further investigative work a consideration if a positive signal is seen. Expectations around whether findings may occur are related to the type of compound being developed, including a chemically synthesized small molecule, a small molecule oncology drug, a biopharmaceutical, an oligonucleotide, a gene therapy/stem cell product, a vaccine, or reformulation of drugs in liposomes or depots. Examples of immunotoxicity/immunogenicity findings will be discussed for all of these types of compound. Overall, it can be concluded that our main tool for evaluation of potential immunotoxicity/immunogenicity for a new drug still remains standard toxicology study testing with key assessment for effects on clinical pathology and lymphoid organs/tissues (weights and cellularity). Additional evaluation from studies using a T cell-dependent antibody response (TDAR) and lymphocyte phenotyping is also valuable, if needed. Thus, using the tools from the past, it is the role of toxicologists to work with clinical teams now and in the future, to interpret findings from nonclinical testing to possible adverse findings in humans.
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Affiliation(s)
- Paul Baldrick
- 1 Covance Laboratories Ltd, England, United Kingdom
- 2 Lincoln School of Pharmacy, University of Lincoln, United Kingdom
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4
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Everds NE, Reindel J, Werner J, Craven WA. Variability of Spleen and Mesenteric Lymph Node in Control Cynomolgus Monkeys ( Macaca fascicularis) from Nonclinical Safety Studies: A Retrospective Assessment. Toxicol Pathol 2018; 47:53-72. [PMID: 30563426 DOI: 10.1177/0192623318809073] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We assessed the variability of spleen and mesenteric lymph node (MLN) microscopic observations and the correlations of these observations with other study data from 478 control cynomolgus monkeys from 53 routine nonclinical safety studies. Spleen weight parameters (absolute and relative to body or brain weights) were highly variable both within a control group on an individual study (up to 5.11-fold) and among animals with the same light microscopic observation. Grades for microscopic observations were also highly variable. The most frequent microscopic observations for spleen were changes in the size and number of germinal centers (58%), acidophilic (hyaline) material in lymphoid follicles (52%), and compound lymphoid follicles (20%). The most frequent microscopic observations in the MLN were eosinophil infiltrates (90%), changes in size and number of germinal centers (42%), and brown pigment (21%). The only meaningful relationships ( r2 > 0.3) were positive correlations between reticuloendothelial hyperplasia and malarial pigment in the spleen and between each of these observations and spleen weight parameters. We conclude that determination of test article-related effects on the immune system in routine monkey toxicology studies requires careful consideration and a weight-of-evidence approach due to the low numbers of animals/group, the inherent variability in spleen and MLN parameters, and the infrequent correlation among immune system-related end points.
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Affiliation(s)
- Nancy E Everds
- 1 Amgen Inc., South San Francisco, California, USA.,2 Seattle Genetics, Bothell, Washington, USA
| | - James Reindel
- 3 Amgen, Inc., Seattle, Washington, USA.,4 MPI Research, Mattawan, Michigan, USA
| | | | - W A Craven
- 1 Amgen Inc., South San Francisco, California, USA
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5
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Kumari D, Nair N, Bedwal RS. Morphological changes in spleen after dietary zinc deficiency and supplementation in Wistar rats. Pharmacol Rep 2018; 71:206-217. [PMID: 30785058 DOI: 10.1016/j.pharep.2018.10.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 10/09/2018] [Accepted: 10/29/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND Study was conducted to determine the effect of dietary zinc deficiency and supplementation on the spleen morphology. METHODS Pre-pubertal Wistar rats (40-50 g) were divided into two groups with 6 sub-groups each viz. zinc control (ZC, 100 μg/g zinc diet), pair fed (PF, 100 μg/g zinc diet), zinc deficient (ZD, <1 μg/g zinc diet, zinc supplementation control (ZCS), zinc supplementation pair-fed (PFS) and zinc supplementation deficient (ZDS, 100 μg/g zinc control diet). Experiments were set for 2- and 4-weeks followed by 4 weeks of zinc supplementation. RESULTS In the present study body weight and BMI decreased significantly along with incidence of splenomegaly as typified by the increased splenic index in deficient groups compared with that of respective control groups. Histopathological changes such as disorganization of red pulp, several infiltered lymphocytes, vacuolization, loss of cellularity, karyolysis, dissolution of matrix, indistinct differentiation between red and white pulp were evident in spleen of 2ZD and 4ZD group animals. Degeneration was more severe after 4 weeks of zinc deficiency as giant cells formation and hypertrophy were also evident. CONCLUSION The findings revealed that zinc deficiency causes growth retardation and splenomegaly. Degenerative and atrophic changes in rat spleen suggest reduced cellular defense potential which will have a direct effect on immunity. Zinc supplementation may prove to be beneficial as there were varying degrees of cellular recovery after cessation of zinc deficiency.
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Affiliation(s)
- Deepa Kumari
- Cell and Molecular Biology Laboratory, Department of Zoology, University of Rajasthan, Jaipur, Rajasthan, India.
| | - Neena Nair
- Cell and Molecular Biology Laboratory, Department of Zoology, University of Rajasthan, Jaipur, Rajasthan, India.
| | - R S Bedwal
- Cell and Molecular Biology Laboratory, Department of Zoology, University of Rajasthan, Jaipur, Rajasthan, India.
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Nagagi YP, Silayo RS, Luziga C, Kweka EJ. In vivo effect of Commiphora swynnertonii ethanolic extracts on Trypanosoma congolense and selected immunological components in mice. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 17:275. [PMID: 28535783 PMCID: PMC5442861 DOI: 10.1186/s12906-017-1785-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 05/10/2017] [Indexed: 11/21/2022]
Abstract
Background The search for alternative trypanocidal compounds which can be available at affordable price is of paramount importance for control of trypanosomosis in human and animals. The current study evaluates the in vivo activity of ethanolic stem bark extracts on Trypanosoma congolense and selected immunological components in an inbred Swiss albino mouse model. Methods Groups of mice infected with T. congolense were treated with the stem bark extracts at a rate of 1000 mg/kg, 1500 mg/kg, and 2000 mg/kg, twice a day in one set and thrice a day in another setting for three days consecutively. Negative (infected and untreated) and positive (infected treated with diminazene diaceturate at 3.5 mg/kg) control groups were used. Levels of parasitaemia were monitored daily for the first 10 days and thereafter 2–3 times per week to the end of experiment. In the other setting, uninfected mice, randomized in groups were treated with the extract but categorized as: thorough mixed extract (TME) and supernatant extract (SE) each at 500 mg/kg and 1500 mg/kg, in 8 hourly intervals respectively for three days consecutively. Control group was administered with phosphate buffered saline with glucose at 0.1 ml/10 g in a similar manner as for the extract. Whole blood and spleen were taken 24 h after the last treatment for hematological and histopathological analysis. Results The groups that received the extracts at 8 hourly intervals drastically reduced the parasitaemia. The higher dose of SE significantly reduced the percentage of lymphocytes (P < 0.05). Both high and low dose of TME significantly reduced lymphocytes percent (P < 0.05) while percent of neutrophils and monocytes increased significantly (P < 0.05). Histopathological changes of the spleen in the mice treated with higher concentrations of the extract of C. swynnertonii were suggestive of lymphocytes toxicity. Conclusion The current study has provided evidence that, in vivo trypanocidal activity of ethanolic bark extracts of C. swynnertonii is probably affected by its negative effect on humoral mediated immune response. Further studies are recommended to determine its potential as an alternative source of lead compounds for trypanocidal drug discovery.
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Affiliation(s)
- R R Maronpot
- National Institute of Environmental Health Sciences/NIH, 111 Alexander Drive, Research Triangle Park, NC 27709, USA.
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Amuno S, Niyogi S, Amuno M, Attitaq J. Heavy metal bioaccumulation and histopathological alterations in wild Arctic hares (Lepus arcticus) inhabiting a former lead-zinc mine in the Canadian high Arctic: A preliminary study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 556:252-263. [PMID: 26974573 DOI: 10.1016/j.scitotenv.2016.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/29/2016] [Accepted: 03/02/2016] [Indexed: 06/05/2023]
Abstract
A preliminary study was undertaken to determine post-mining baseline accumulation of selected trace metals, and histopathological alterations in free-living arctic hares (Lepus arcticus) inhabiting the vicinity of a former lead-zinc mine located on North Baffin Island in the Canadian High Arctic. Trace metal analysis included measurement of As, Cd, Fe, Pb and Zn in tissues, and histopathological assessment comprised of evaluation and scoring the severity of metal-induced hepatic and renal lesions. Metal contents in hepatic and renal tissues from hares from the mine area compared with the reference locations did not differ significantly suggesting that the animals are not uniformly exposed to background levels of metals in the environment. However, relatively higher accumulation pattern of Pb and Cd were noted in liver tissues of hare from the mine area compared to the background area, but did not induce increased lesions. Surface soils near the mine area contained relatively higher levels of trace metals (Zn>Mn>Pb>Cd>As) compared to reference soils, and with soil levels of Cd showing strong correlation with Cd accumulation in kidney tissues. Generally, both case and reference animals showed similar but varying severities of hepatic and renal lesions at the sublethal level, notably vascular congestion, occasional large hepatocyte nuclei, binucleate hepatocytes, yellow-brown pigmentation in the cytoplasm of hepatocytes and clustering of lymphocytes. Only hares with relatively higher accumulation of Pb from the mine area showed evidence of renal edema and hemorrhage of the capsular surface. This study constitutes the first assessment of metal induced histopathological alterations in arctic hares exposed to a historical mining area in the high arctic.
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Affiliation(s)
- S Amuno
- Nunavut Impact Review Board, Cambridge Bay, Nunavut, Canada.
| | - S Niyogi
- Department of Biology, University of Saskatchewan, Saskatoon, Canada
| | - M Amuno
- School of Engineering and ICT, University of Tasmania, Hobart, Australia
| | - J Attitaq
- Ikajutit Hunters and Trappers Association, Arctic Bay, Nunavut, Canada
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9
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Snyder PW, Everds NE, Craven WA, Werner J, Tannehill-Gregg SH, Guzman RE. Maturity-related Variability of the Thymus in Cynomolgus Monkeys (Macaca fascicularis). Toxicol Pathol 2016; 44:874-91. [PMID: 27226125 DOI: 10.1177/0192623316649258] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Terminal body weights (TBWs), thymus weight parameters, and thymus morphology were retrospectively evaluated in 453 cynomolgus monkeys assigned to control groups on nonclinical toxicity studies. Morphology of bone, ovary, and testis/epididymis were used to determine maturity status of individual animals. There was no correlation between TBW and thymus weight (absolute and/or relative to TBW or brain weight). Thymus weight parameters and grades of decreased lymphocytes in the thymus were highly variable in immature animals compared to mature animals. There was also high (up to 11-fold) variability of thymus weight parameters within a given control group on the same study (generally 3 or 4 animals per sex). Several parameters evaluated had more pronounced age-related changes in males when compared to females. Our results demonstrate the inherent variability of thymus weight parameters and morphologic observations for cynomolgus monkeys on toxicology studies. Changes in thymus parameters in cynomolgus monkeys are unreliable indicators of immunomodulation or immunotoxicity in the absence of other relevant findings. Therefore, the thymus parameters commonly evaluated in preclinical safety assessments should not be the primary data set used to determine the presence of a direct test article-related effect on the immune system.
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Affiliation(s)
- Paul W Snyder
- Experimental Pathology Laboratories, West Lafayette, Indiana, USA
| | | | - W A Craven
- Amgen Inc., South San Francisco, California, USA
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10
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Kalmar I, Berndt A, Yin L, Chiers K, Sachse K, Vanrompay D. Host-pathogen interactions in specific pathogen-free chickens following aerogenous infection with Chlamydia psittaci and Chlamydia abortus. Vet Immunol Immunopathol 2015; 164:30-9. [PMID: 25638671 DOI: 10.1016/j.vetimm.2014.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 12/05/2014] [Accepted: 12/31/2014] [Indexed: 10/24/2022]
Abstract
Although Chlamydia (C.) psittaci infections are recognized as an important factor causing economic losses and impairing animal welfare in poultry production, the specific mechanisms leading to severe clinical outcomes are poorly understood. In the present study, we comparatively investigated pathology and host immune response, as well as systemic dissemination and expression of essential chlamydial genes in the course of experimental aerogeneous infection with C. psittaci and the closely related C. abortus, respectively, in specific pathogen-free chicks. Clinical signs appeared sooner and were more severe in the C. psittaci-infected group. Compared to C. abortus infection, more intense systemic dissemination of C. psittaci correlated with higher and faster infiltration of immune cells, as well as more macroscopic lesions and epithelial pathology, such as hyperplasia and erosion. In thoracic air sac tissue, mRNA expression of immunologically relevant factors, such as IFN-γ, IL-1β, IL-6, IL-17, IL-22, LITAF and iNOS was significantly stronger up-regulated in C. psittaci- than in C. abortus-infected birds between 3 and 14 days post-infection. Likewise, transcription rates of the chlamydial genes groEL, cpaf and ftsW were consistently higher in C. psittaci during the acute phase. These findings illustrate that the stronger replication of C. psittaci in its natural host also evoked a more intense immune response than in the case of C. abortus infection.
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Affiliation(s)
- Isabelle Kalmar
- Department of Molecular Biotechnology and Immunology, Ghent University, Belgium
| | - Angela Berndt
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany
| | - Lizi Yin
- Department of Molecular Biotechnology and Immunology, Ghent University, Belgium
| | - Koen Chiers
- Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Belgium
| | - Konrad Sachse
- Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
| | - Daisy Vanrompay
- Department of Molecular Biotechnology and Immunology, Ghent University, Belgium
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Brennan FR, Cauvin A, Tibbitts J, Wolfreys A. Optimized nonclinical safety assessment strategies supporting clinical development of therapeutic monoclonal antibodies targeting inflammatory diseases. Drug Dev Res 2014; 75:115-61. [PMID: 24782266 DOI: 10.1002/ddr.21173] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 02/23/2014] [Indexed: 12/19/2022]
Abstract
An increasing number of immunomodulatory monoclonal antibodies (mAbs) and IgG Fc fusion proteins are either approved or in early-to-late stage clinical trials for the treatment of chronic inflammatory conditions, autoimmune diseases and organ transplant rejection. The exquisite specificity of mAbs, in combination with their multi-functional properties, high potency, long half-life (permitting intermittent dosing and prolonged pharamcological effects), and general lack of off-target toxicity makes them ideal therapeutics. Dosing with mAbs for these severe and debilitating but often non life-threatening diseases is usually prolonged, for several months or years, and not only affects adults, including sensitive populations such as woman of child-bearing potential (WoCBP) and the elderly, but also children. Immunosuppression is usually a therapeutic goal of these mAbs and when administered to patients whose treatment program often involves other immunosuppressive therapies, there is an inherent risk for frank immunosuppression and reduced host defence which when prolonged increases the risk of infection and cancer. In addition when mAbs interact with the immune system they can induce other adverse immune-mediated drug reactions such as infusion reactions, cytokine release syndrome, anaphylaxis, immune-complex-mediated pathology and autoimmunity. An overview of the nonclinical safety assessment and risk mitigation strategies utilized to characterize these immunomodulatory mAbs and Fc fusion proteins to support first-in human (FIH) studies and futher clinical development in inflammatory disease indications is provided. Specific emphasis is placed on the design of studies to qualify animal species for toxicology studies, early studies to investigate safety and define PK/PD relationships, FIH-enabling and chronic toxicology studies, immunotoxicity, developmental, reproductive and juvenile toxicity studies and studies to determine the potential for immunosuppression and reduced host defence against infection and cancer. Nonclinical strategies to facilitate clinical and market entry in the most efficient timeframe are presented.
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Affiliation(s)
- Frank R Brennan
- Preclinical Safety, New Medicines, UCB-Celltech, Slough, SL1 3WE, UK
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12
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Hing SL, Ravichandran A, Escano J, Cooley J, Austin F, Lu SE, Pruett S, Smith L. Toxicological Evaluation of Occidiofungin against Mice and Human Cancer Cell Lines. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/pp.2014.511118] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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13
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Rubab I, Routray I, Mahmood A, Bashir S, Shinkafi TS, Khan F, Ali S. Mineral pitch stimulates humoral, cellular and innate immune responses in mice. PHARMACEUTICAL BIOLOGY 2013; 51:997-1007. [PMID: 23750745 DOI: 10.3109/13880209.2013.774027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
CONTEXT Mineral pitch (MP), a traditional medicine, is proposed to boost immunity in conditions that suppress Th1 cytokines such as AIDS/HIV, tuberculosis, leishmaniasis and cancer. OBJECTIVE This study investigates the immunoregulatory mechanisms of MP in innate, humoral and cell-mediated immunity. MATERIALS AND METHODS Mice given MP (100, 200, 300 or 400 mg/kg, orally) for 10 consecutive days were immunized intravenously with goat RBC or ovalbumin, and investigated for plaque-forming cells (PFC), hemagglutination titer, hypersensitivity response, lymphocyte proliferation and macrophage function. RESULTS MP increased PFC (330.2 versus 182.2/10⁶ splenocytes) in mice immunized with goat RBC and elicited ovalbumin-specific IgG titer at 400 mg/kg. Increase in Th1 immunity was correlated with the increased level of IFN-γ (724 versus 470 pg/ml) and decreased IL-4 (96 versus 178 pg/ml). CD4⁺/CD3⁺ ratio and delayed-type hypersensitivity response also increased to, respectively, 20.62 ± 0.59 (versus 16.47 ± 0.72) and 1.59 ± 0.12 (versus 0.87 ± 0.10 mm) in MP-treated mice. MP increased lymphocyte proliferation (11.14 ± 0.60 versus 5.81 ± 0.40 SI) and macrophage phagocyte response (0.24 ± 0.02 versus 0.15 ± 0.009), expressed as absorbance at 570 nm, but decreased nitrite production (17.4 ± 1.10 versus 24.3 ± 1.30 µM/10⁶ cells). We also observed an increased bone marrow cellularity (24.5 ± 1.10 versus 17.10 ± 0.70 cells/femur) and WBC count (12 667 ± 377 versus 9178 ± 213 cells/mm³) following MP treatment. There was no sign of toxicity at 400 mg/kg, 1/12th of reported LD₅₀. CONCLUSION MP elicits a dose-dependent Th1 immune response.
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Affiliation(s)
- Ishrina Rubab
- Department of Biochemistry, Faculty of Science, Jamia Hamdard-Hamdard University, Hamdard Nagar, New Delhi, India
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14
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Dobrovolskaia MA, McNeil SE. Understanding the correlation between in vitro and in vivo immunotoxicity tests for nanomedicines. J Control Release 2013; 172:456-66. [PMID: 23742883 DOI: 10.1016/j.jconrel.2013.05.025] [Citation(s) in RCA: 171] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 05/10/2013] [Accepted: 05/27/2013] [Indexed: 02/02/2023]
Abstract
Preclinical characterization of novel nanotechnology-based formulations is often challenged by physicochemical characteristics, sterility/sterilization issues, safety and efficacy. Such challenges are not unique to nanomedicine, as they are common in the development of small and macromolecular drugs. However, due to the lack of a general consensus on critical characterization parameters, a shortage of harmonized protocols to support testing, and the vast variety of engineered nanomaterials, the translation of nanomedicines into clinic is particularly complex. Understanding the immune compatibility of nanoformulations has been identified as one of the important factors in (pre)clinical development and requires reliable in vitro and in vivo immunotoxicity tests. The generally low sensitivity of standard in vivo toxicity tests to immunotoxicities, inter-species variability in the structure and function of the immune system, high costs and relatively low throughput of in vivo tests, and ethical concerns about animal use underscore the need for trustworthy in vitro assays. Here, we consider the correlation (or lack thereof) between in vitro and in vivo immunotoxicity tests as a mean to identify useful in vitro assays. We review literature examples and case studies from the experience of the NCI Nanotechnology Characterization Lab, and highlight assays where predictability has been demonstrated for a variety of nanomaterials and assays with high potential for predictability in vivo.
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Affiliation(s)
- Marina A Dobrovolskaia
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick Inc., NCI-Frederick, Frederick, MD 21702, USA
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15
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Clichici S, Biris AR, Catoi C, Filip A, Tabaran F. Short-term splenic impact of single-strand DNA functionalized multi-walled carbon nanotubes intraperitoneally injected in rats. J Appl Toxicol 2013; 34:332-44. [PMID: 23677818 DOI: 10.1002/jat.2883] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/10/2013] [Accepted: 03/10/2013] [Indexed: 11/07/2022]
Abstract
In recent years, a great deal of studies have focused on the possible toxicity of carbon nanotubes (CNT), as a result of their potential applications in the field of nanotechnologies. The investigation of spleen toxicity is part of the carbon nanotubes-induced toxicity assessment. In this study, we investigated the possible toxic effects of CNT on the rat spleen, after intraperitoneally (i.p.) administration of a single dose [1.5 ml; 2 mg multi-walled (MW) CNT per body weight (bw)] of multi-walled carbon nanotubes (exterior diameter 15-25 nm, interior diameter 10-15 nm, surface 88 m(2) g(-1) ) functionalized 1:1 with single-strand DNA (ss-DNA-MWCNT, 270 mg l(-1) ). CNT functionalization with DNA determines a stable dispersion in the body fluids. For the detection of carbon nanotubes in the spleen, Raman spectroscopy, histopathologic examination, confocal microscopy and transmission electron microscopy (TEM) were performed at different time points (1, 6, 24, 48 and 144 h) after MWCNT administration. The dynamics of oxidative stress parameters (malondialdehyde, protein carbonyls and reduced glutathione), along with nitrosative stress parameters (nitric oxide, inducible NO synthase), the pro-inflammatory cytokines [interleukin-(IL)-1β] and the number of cells expressing caspase 3 and proliferating cell nuclear antigen (PCNA) were assessed. Our results indicate that, after i.p. administration, MWCNT translocate progressively in the spleen, with a peak of concentration after 48 h, and determine lymphoid hyperplasia and an increase in the number of cells which undergo apoptosis, in parallel with the enhancement of the mitosis in the white pulp and with transient alterations of oxidative stress and inflammation that need further investigations for a longer period of monitoring.
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Affiliation(s)
- Simona Clichici
- Department of Physiology, University of Medicine and Pharmacy, Cluj-Napoca, Romania
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16
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Descotes J. Safety immunopharmacology: evaluation of the adverse potential of pharmaceuticals on the immune system. J Pharmacol Toxicol Methods 2012; 66:79-83. [PMID: 22587937 PMCID: PMC7111030 DOI: 10.1016/j.vascn.2012.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/24/2012] [Accepted: 05/05/2012] [Indexed: 02/08/2023]
Abstract
The ICH S6R1 and S8 guidelines define a general framework for the immunotoxicity evaluation of biotechnology-derived pharmaceuticals and human pharmaceuticals, respectively. As severe and unpredicted adverse events dramatically showed in the recent years that the immune system is a critical aspect of drug safety, this framework needs to be revisited to enhance the prediction of nonclinical immune safety evaluation. Safety immunopharmacology is deemed to contribute to this awaited improvement by enabling early screening of the potential for drug candidates to induce unexpected immunosuppressive and immunostimulatory effects as well as nonimmune-mediated hypersensitivity reactions. Dedicated safety immunopharmacology can also generate mechanistic data to determine which relevant additional immunotoxicity studies should be conducted. Immunological assays and models that can be considered for use in the context of safety pharmacology studies are presented as well as perspectives for their timely development.
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Affiliation(s)
- Jacques Descotes
- Poison Center and Pharmacovigilance Department, Lyon University Hospitals, and Claude Bernard University, Lyon, France.
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17
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Tan W, Cooley J, Austin F, Lu SE, Pruett SB, Smith L. Nonclinical Toxicological Evaluation of Occidiofungin, a Unique Glycolipopeptide Antifungal. Int J Toxicol 2012; 31:326-36. [DOI: 10.1177/1091581812445185] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Occidiofungin, a glycolipopeptide obtained from the liquid culture of Burkholderia contaminans MS14, has been identified as a novel fungicide. The present study was designed to initially assess the in vitro toxicity in a rat hepatoma (H4IIE) cell line and acute toxicological effects of occidiofungin using a mouse model. In vitro toxicity was observed in all variables at 5 μmol/L. B6C3F1 mice were given single and repeat doses of occidiofungin up to 20 mg/kg. Key effects were a reduction in body and organ weights. However, no significant decrease in body weight was noted at a dose of 1 mg/kg, which is comparable to the dose level of other cyclic glycopeptide antifungal agents currently approved for human use. Microscopic examination of treated mice did not identify any signs of organ-specific toxicity at the dose levels tested.
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Affiliation(s)
- Wei Tan
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Jim Cooley
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Frank Austin
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Shi-En Lu
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS, USA
| | - Stephen B. Pruett
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Leif Smith
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
- Department of Biological Sciences, Texas A & M University, College Station, TX, USA(current address)
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18
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Ward JM, Rehg JE, Morse HC. Differentiation of rodent immune and hematopoietic system reactive lesions from neoplasias. Toxicol Pathol 2012; 40:425-34. [PMID: 22215512 PMCID: PMC3443630 DOI: 10.1177/0192623311431467] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The immune and hematopoietic systems play an important role in the normal homeostasis of blood and blood cells and for immune responses to endogenous and exogenous processes and insults. In order to interpret histopathologic changes in the immune and hematopoietic systems, it is important to understand the normal anatomy and histology of the thymus, spleen, lymph nodes, bone marrow, and other tissues. The thymus, spleen, and lymph nodes can be categorized by anatomical compartments, each of which contributes to specific immune functions. Lesions may be diagnosed by interpretive or descriptive (semiquantitative) methods. The interpretation of these tissues by lesion in anatomical compartments should allow for better understanding of these reactions and more definitive pathologic findings. Proliferative lesions may be difficult to differentiate from lymphomas and leukemias. The use of immunohistochemistry, compartmental pathology, and methods for the evaluation of clonality will make interpretation easier.
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Affiliation(s)
- Jerrold M Ward
- Global VetPathology and Laboratory of Immunopathology, NIAID, NIH, Bethesda, Maryland 20892, USA.
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19
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Gomuttapong S, Pewphong R, Choeisiri S, Jaroenporn S, Malaivijitnond S. Testing of the estrogenic activity and toxicity ofStephania venosaherb in ovariectomized rats. Toxicol Mech Methods 2012; 22:445-57. [DOI: 10.3109/15376516.2012.668573] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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20
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Abstract
Enhanced histopathology (EH) of the immune system is a tool that the pathologist can use to assist in the detection of lymphoid organ lesions when evaluating a suspected immunomodulatory test article within a subchronic study or as a component of a more comprehensive, tiered approach to immunotoxicity testing. There are three primary points to consider when performing EH: (1) each lymphoid organ has separate compartments that support specific immune functions; (2) these compartments should be evaluated individually; and (3) semiquantitative descriptive rather than interpretive terminology should be used to characterize any changes. Enhanced histopathology is a screening tool that should be used in conjunction with study data including clinical signs, gross changes, body weight, spleen and thymus weights, other organ or tissue changes, and clinical pathology. Points to consider include appropriate tissue collection, sectioning, and staining; lesion grading; and diligent comparison with concurrent controls. The value of EH of lymphoid organs is to aid in the identification of target cell type, changes in cell production and cell death, changes in cellular trafficking and recirculation, and determination of mechanism of action.
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Affiliation(s)
- Susan A Elmore
- National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
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21
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Segner H, Wenger M, Möller AM, Köllner B, Casanova-Nakayama A. Immunotoxic effects of environmental toxicants in fish - how to assess them? ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2011; 19:2465-2476. [PMID: 22828877 DOI: 10.1007/s11356-012-0978-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 05/09/2012] [Indexed: 06/01/2023]
Abstract
Numerous environmental chemicals, both long-known toxicants such as persistent organic pollutants as well as emerging contaminants such as pharmaceuticals, are known to modulate immune parameters of wildlife species, what can have adverse consequences for the fitness of individuals including their capability to resist pathogen infections. Despite frequent field observations of impaired immunocompetence and increased disease incidence in contaminant-exposed wildlife populations, the potential relevance of immunotoxic effects for the ecological impact of chemicals is rarely considered in ecotoxicological risk assessment. A limiting factor in the assessment of immunotoxic effects might be the complexity of the immune system what makes it difficult (1) to select appropriate exposure and effect parameters out of the many immune parameters which could be measured, and (2) to evaluate the significance of the selected parameters for the overall fitness and immunocompetence of the organism. Here, we present - on the example of teleost fishes - a brief discussion of how to assess chemical impact on the immune system using parameters at different levels of complexity and integration: immune mediators, humoral immune effectors, cellular immune defenses, macroscopical and microscopical responses of lymphoid tissues and organs, and host resistance to pathogens. Importantly, adverse effects of chemicals on immunocompetence may be detectable only after immune system activation, e.g., after pathogen challenge, but not in the resting immune system of non-infected fish. Current limitations to further development and implementation of immunotoxicity assays and parameters in ecotoxicological risk assessment are not primarily due to technological constraints, but are related from insufficient knowledge of (1) possible modes of action in the immune system, (2) the importance of intra- and inter-species immune system variability for the response against chemical stressors, and (3) deficits in conceptual and mechanistic assessment of combination effects of chemicals and pathogens.
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Affiliation(s)
- Helmut Segner
- Centre for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Laenggass-Strasse 122, 3012, Bern, Switzerland.
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22
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Brennan FR, Morton LD, Spindeldreher S, Kiessling A, Allenspach R, Hey A, Muller PY, Frings W, Sims J. Safety and immunotoxicity assessment of immunomodulatory monoclonal antibodies. MAbs 2010; 2:233-55. [PMID: 20421713 PMCID: PMC2881251 DOI: 10.4161/mabs.2.3.11782] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2010] [Accepted: 03/23/2010] [Indexed: 12/31/2022] Open
Abstract
Most therapeutic monoclonal antibodies (mAbs) licensed for human use or in clinical development are indicated for treatment of patients with cancer and inflammatory/autoimmune disease and as such, are designed to directly interact with the immune system. A major hurdle for the development and early clinical investigation of many of these immunomodulatory mAbs is their inherent risk for adverse immune-mediated drug reactions in humans such as infusion reactions, cytokine storms, immunosuppression and autoimmunity. A thorough understanding of the immunopharmacology of a mAb in humans and animals is required to both anticipate the clinical risk of adverse immunotoxicological events and to select a safe starting dose for first-in-human (FIH) clinical studies. This review summarizes the most common adverse immunotoxicological events occurring in humans with immunomodulatory mAbs and outlines non-clinical strategies to define their immunopharmacology and assess their immunotoxic potential, as well as reduce the risk of immunotoxicity through rational mAb design. Tests to assess the relative risk of mAb candidates for cytokine release syndrome, innate immune system (dendritic cell) activation and immunogenicity in humans are also described. The importance of selecting a relevant and sensitive toxicity species for human safety assessment in which the immunopharmacology of the mAb is similar to that expected in humans is highlighted, as is the importance of understanding the limitations of the species selected for human safety assessment and supplementation of in vivo safety assessment with appropriate in vitro human assays. A tiered approach to assess effects on immune status, immune function and risk of infection and cancer, governed by the mechanism of action and structural features of the mAb, is described. Finally, the use of immunopharmacology and immunotoxicity data in determining a minimum anticipated biologic effect Level (MABEL) and in the selection of safe human starting dose is discussed.
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Affiliation(s)
- Frank R Brennan
- Novartis Biologicals, Translational Sciences and Safety, Basel, Switzerland.
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23
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Abstract
A brief historical perspective of immunotoxicology is presented describing the early development of predictive screening tests to identify xenobiotics that may cause immunosuppression or skin sensitization. This includes a discussion of the evolution of the discipline to support a better understanding of basic -science and improvement of human risk assessment. The last section describes the need for additional validated screening tests and recent efforts to address this gap in the other areas of immunotoxicology including food and respiratory allergy, autoimmunity and immunostimulation.
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24
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Dietert RR. New developments in the assessment of developmental immunotoxicology. J Immunotoxicol 2009; 2:185-9. [PMID: 18958672 DOI: 10.1080/15476910500362788] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Recent progress has been made in directly comparing the risk of immunotoxicity following exposure to various drugs and environmental chemicals during different stages of life. With the availability of an increased developmental immunotoxicology database, new concepts of effective immunotoxicological risk assessment have emerged. From the standpoint of risk assessment, recent results suggest that there is greater value obtained from exposure-assessment of non-adults than can be derived solely from adult-exposure-outcome data. This is hardly surprising given the fact that, for the vast majority of known immunotoxicants compared across age groups, the non-adult stages are more sensitive than adults for risk of clinically important immunomodulation. Therefore, if immunotoxicity testing is to identify risk for the more susceptible subpopulations, the adult is not the informative model. This brief review, based on the Immuntoxicology III conference presentation, describes the data supporting age-based differences in sensitivity to immunotoxicants, differences in immunotoxic outcomes, and the potential benefits of utilizing non-adult exposures and life-stage-relevant immune assessment. In essence, the issue is whether historic adult immunotoxicity testing strategies can continue to ensure adequate protection of the most vulnerable subpopulations in the face of recent developmental immunotoxicological data. The review describes the possible benefits of substituting non-adult exposures for adult exposures in future assessment protocols.
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Affiliation(s)
- Rodney R Dietert
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA.
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25
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Weir AB. Hazard Identification and Risk Assessment for Biologics Targeting the Immune System. J Immunotoxicol 2008; 5:3-10. [DOI: 10.1080/15476910801897409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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26
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Randall KJ, Pearse G. A Dual-label Technique for the Immunohistochemical Demonstration of T-Lymphocyte Subsets in Formalin-fixed, Paraffin-Embedded Rat Lymphoid Tissue. Toxicol Pathol 2008; 36:795-804. [DOI: 10.1177/0192623308322311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Immunotoxicology has developed into an integral regulatory requirement of the toxicological assessment of xenobiotics. Histopathological assessment of lymphoid tissues can provide genuine insight into perturbations of lymphoid cell populations. To facilitate retrospective examination of lymphoid organs should concerns over immunotoxicity be raised, we have endeavored to develop a panel of immunohistochemical techniques to demonstrate T-cells and T-cell subsets in formalin-fixed, paraffin-embedded rat lymphoid tissues. We were successful in developing methods for CD3 and CD8 but failed to arrive at a satisfactory technique for the direct demonstration of CD4 in these tissues. Taking the assumption that the majority of mature T-cells are either CD4+ orCD8+, we have combined our methods for CD3 and CD8 in a novel dual-labeling IHC method to simultaneously demonstrate CD3, CD8, and, by implication, CD4 in rat spleen, thymus, lymph node, and Peyer’s patch.
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Affiliation(s)
- Kevin J. Randall
- AstraZeneca, Alderley Park, Macclesfield, Cheshire, United Kingdom
| | - Gail Pearse
- AstraZeneca, Alderley Park, Macclesfield, Cheshire, United Kingdom
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27
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Burns-Naas LA, Hastings KL, Ladics GS, Makris SL, Parker GA, Holsapple MP. What’s So Special about the Developing Immune System? Int J Toxicol 2008; 27:223-54. [DOI: 10.1080/10915810801978110] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The evolution of the subdiscipline of developmental immunotoxicology (DIT) as it exists today has been shaped by significant regulatory pressures as well as key scientific advances. This review considers the role played by legislation to protect children’s health, and on the emergence of immunotoxcity and developmental immunotoxicity guidelines, as well as providing some context to the need for special attention on DIT by considering the evidence that the developing immune system may have unique susceptibilities when compared to the adult immune system. Understanding the full extent of this potential has been complicated by a paucity of data detailing the development of the immune system during critical life stages as well as by the complexities of comparisons across species. Notably, there are differences between humans and nonhuman species used in toxicity testing that include specific differences relative to the timing of the development of the immune system as well as more general anatomic differences, and these differences must be factored into the interpretation of DIT studies. Likewise, understanding how the timing of the immune development impacts on various immune parameters is critical to the design of DIT studies, parameters most extensively characterized to date in young adult animals. Other factors important to DIT, which are considered in this review, are the recognition that effects other than suppression (e.g., allergy and autoimmunity) are important; the need to improve our understanding of how to assess the potential for DIT in humans; and the role that pathology has played in DIT studies in test animals. The latter point receives special emphasis in this review because pathology evaluations have been a major component of standard nonclinical toxicology studies, and could serve an important role in studies to evaluate DIT. This possibility is very consistent with recommendations to incorporate a DIT evaluation into standard developmental and reproductive toxicology (DART) protocols. The overall objective of this review is to provide a ‘snapshot’ of the current state-of-the-science of DIT. Despite significant progress, DIT is still evolving and it is our hope that this review will advance the science.
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Affiliation(s)
- Leigh Ann Burns-Naas
- Drug Safety Research and Development, Pfizer Global Research and Development, San Diego, CA 92064, California, USA
| | - Kenneth L. Hastings
- United States Food and Drug Administration, Center for Drug Evaluation Research, Office of New Drugs, Rockville, Maryland, USA
| | | | - Susan L. Makris
- United States Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC, USA
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28
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De Jong WH, Van Loveren H. Screening of xenobiotics for direct immunotoxicity in an animal study. Methods 2007; 41:3-8. [PMID: 17161297 DOI: 10.1016/j.ymeth.2006.09.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Accepted: 09/22/2006] [Indexed: 11/28/2022] Open
Abstract
It has now been recognised that the immune system as a whole can be the target for xenobiotic induced toxicity. The discipline of immuntoxicology encompasses non specific direct immunotoxicity and immunostimulation, and specific responses like hypersensitivity and autoimmunity. Direct immunotoxicity can be determined in tiered studies, TIER 1 being a general toxicity study with emphasis on evaluation of organs belonging to the immune system, TIER 2 investigating the effects of xenobiotics on immune functionality in immunological challenge experiments. In the TIER 1 study, organ weights and histopathological evaluation of immune organs like spleen, thymus, lymph nodes, blood and bone marrow may detect the occurrence of direct immunotoxicity. The follow up studies in the TIER 2 phase can then determine the extent of the immunosuppression and identify which specific parts or cellular components of the immune system are involved. In view of the complexity of the immune system and the multitude of interactions within the immune system in vivo animal experiments are needed to investigate xenobiotics for their potential immunotoxicity. In vitro assays with in vivo exposed cells of the immune system may present additional information on the mechanisms involved in the observed direct immunotoxicity.
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Affiliation(s)
- Wim H De Jong
- Laboratory for Toxicology, Pathology and Genetics, National Institute for Public Health and the Environment (Rijksinstituut voor Volksgezondheid en Milieu, RIVM), P.O. Box 1, 3720 BA Bilthoven, The Netherlands.
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29
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Abstract
Immunotoxicology is an important aspect of the safety evaluation of drugs and chemicals. Immunosuppression, (unspecific) immunostimulation, hypersensitivity and autoimmunity are the four types of immune-mediated adverse effects. However, the nonclinical assessment of immunotoxicity is at present often restricted to animal models and assays to predict unexpected immunosuppression. There is, however, no general consensus that a variety of assays can be considered depending on the compound to be tested. A major issue is whether histological examination of the thymus, spleen, lymphoid organs and Peyer's patches is a reliable predictor of immunosuppression or whether immune function should also be assessed. A T-dependent antibody response assay, either the plaque-forming cell assay or anti-keyhole limpet haemocyanin enzyme-linked immunosorbant assay, is recommended as a first-line assay. A variety of assays, including lymphocyte subset analysis, natural killer-cell activity, lymphocyte proliferation, delayed-type hypersensitivity, cytotoxic T-lymphocyte activity and macrophage/neutrophil function assays, can also be used. In certain circumstances, host resistance assays can be considered. With the exception of contact sensitisation, very few animal models and assays can reliably predict the potential for (unspecific) immunostimulation, hypersensitivity or autoimmunity. A major limitation of immunotoxicity risk assessment is the lack of human data. Immunological end points and clinical criteria to be included in clinical trials and epidemiological studies have to be carefully standardised and validated.
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Affiliation(s)
- Jacques Descotes
- Centre Antipoison - Centre de Pharmacovigilance, 162 Avenue Lacassagne, 69424 Lyon cedex 03, France.
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30
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Dietert RR, Holsapple MP. Methodologies for developmental immunotoxicity (DIT) testing. Methods 2007; 41:123-31. [PMID: 17161309 DOI: 10.1016/j.ymeth.2006.06.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 06/06/2006] [Indexed: 10/23/2022] Open
Abstract
Developmental immunotoxicity has gained increasing recognition as a significant factor influencing the risk of later life disease. Based on the data collected thus far on different chemicals and drugs, the developing immune system can be significantly more sensitive than the adult immune system to xenobiotic-induced insult. There are distinct differences between the immune system surrounding birth and that in the mature adult as well as differences in the nature of immunotoxic changes based on age. Immunosuppresssion is not the only concern. Immunotoxic changes that increase the risk for allergic or autoimmune responses should also be considered. Therefore, one should not assume that immunotoxicity assays validated for adult exposure assessment are inherently the most predictive for developmental immunotoxicology (DIT) evaluation. Many of those adult-based protocols were developed solely to detect immunosuppression, whereas DIT concerns include shifts in immune balance. For this reason, it is useful to examine the various immune endpoints that have been employed in recent perinatal immunotoxicity studies, compare those against routine adult immunotoxicity evaluation protocols, and consider the options that are available for effective DIT testing. The results published on several chemicals and drugs in recent years suggest that functional tests are a front-line priority for perinatal immunotoxicity detection and that a combination of at least two functional tests (such as a multi-isotype T-dependent antibody response (TDARs), and a cell-mediated immune response assay such as the delayed-type hypersensitivity assay and/or T cell or NK cytotoxicity assays) should be paired with immune cell populations and histopathological analysis. Cytokine production measurements offer outstanding promise and may eventually be able to be substituted for other more laborious procedures. However, multi-cytokine analysis needs to be standardized in terms of optimum source for analysis and protocol.
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Affiliation(s)
- Rodney R Dietert
- Department of Microbiology and Immunology, College of Veterinary Medicine, C-5-135 VMC, N.Tower Rd., Cornell University, Ithaca, NY 14853, USA.
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31
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Abstract
The thymus is a primary or central lymphoid organ in which T lymphocytes undergo differentiation and maturation autonomously within the cortex, without the need for antigenic stimulation, and it is essential for the normal development and function of the immune system. The thymus has been shown to be a sensitive target organ following exposure to immunotoxicants and endogenous corticosteroids, and a decrease in size or weight is often one of the first noted measures of compound-induced effects with cortical lymphocytes (thymocytes) being especially susceptible. Therefore, changes in thymus histopathology and architecture are considered to be of particular relevance for immunotoxicity screening. The separate compartments in each lymphoid organ should be evaluated separately and descriptive rather than interpretive terminology should be used to characterize changes within those compartments (Haley et al., 2005). Therefore, enhanced histopathological evaluation of the thymus involves the determination of the size and cellularity of the cortex and medulla, which should be noted separately. Other changes to evaluate include, but are not limited to, increased lymphocyte apoptosis, lymphocyte necrosis, cortex:medulla ratio and an increase or decrease in the epithelial component of the thymus.
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Affiliation(s)
- Susan A Elmore
- Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences/NIH, 111 Alexander Drive, Research Triangle Park, NC 27709, USA.
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32
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Abstract
The spleen is the largest secondary lymphoid organ, is considered the draining site for compounds that are administered intravenously, and is therefore considered an important organ to evaluate for treatment-related lesions. Due to the presence of B and T lymphocytes, the immunotoxic effects of xenobiotics or their metabolites on these cell populations may be reflected in the spleen. Therefore it is one of the recommended organs to evaluate for enhanced histopathology of the immune system. The two major functional zones of the spleen are the hematogenous red pulp and the lymphoid white pulp (periarteriolar sheaths, follicles and marginal zones). For enhanced histopathology, these splenic compartments should be evaluated separately for changes in size and cellularity, and descriptive rather than interpretive terminology should be used to characterize any changes (Haley et al., 2005). Moreover, germinal center development within the lymphoid follicles should be noted as increased or decreased.
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Affiliation(s)
- Susan A Elmore
- Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences/NIH, 111 Alexander Drive, Research Triangle Park, NC 27709, USA.
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33
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Schulte A, Ruehl-Fehlert C. Regulatory aspects of immunotoxicology. ACTA ACUST UNITED AC 2006; 57:385-9. [PMID: 16713214 DOI: 10.1016/j.etp.2006.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 03/30/2006] [Indexed: 10/24/2022]
Abstract
Since years, differences among the regulatory requirements on preclinical immunotoxicity testing for pharmaceuticals in the EU, Japan and US indicated a need for an internationally accepted approach. Requests for immunotoxicity investigations are also addressed by guidelines in non-drug areas. While some contain more detailed information in their requirements, other regulations comprise only vague descriptions for consideration of (non-intended) effects on the immune effects. Since 2002, the International Conference on Harmonisation (ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use put effort in the development of a harmonised approach for testing of immunosuppression and immunoenhancement. Consensus on the ICH S8 guideline on immunotoxicity testing for pharmaceuticals was achieved which now can be implemented into national regulations. The new concept contains in-depth testing, e.g., by functional tests in a concern/weight of evidence approach if the standard toxicity studies or other causes of concern give evidence of an immunotoxic potential or when the target populations are specifically vulnerable. It is expected that the progress on immunotoxicity testing reached by the ICH process will also have an impact on other regulatory areas. Additionally, the regulatory differences in testing requirements on immunotoxicity in other pharmaceutical areas including biotechnology-derived drugs, medicinal products and vaccines and in non-drug areas consisting of chemicals, agrochemicals or food additives are briefly highlighted.
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Affiliation(s)
- Agnes Schulte
- Federal Institute for Risk Assessment, Toxicology of Chemicals, Berlin, Germany.
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34
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Frieke Kuper C. General aspects of immunotoxicology including validation issues. ACTA ACUST UNITED AC 2006; 57:363-6. [PMID: 16709446 DOI: 10.1016/j.etp.2006.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 03/30/2006] [Indexed: 11/30/2022]
Abstract
Histologic examination of lymphoid organs has revealed immunotoxic effects of a broad range of substances. The thymus has proven especially sensitive. The relative lack of sensitivity of mucosa-associated lymphoid cells and tissues may be due to shortcomings in the way they are examined. Validation of ways to examine mucosal lymphoid tissues and cells and development of histopathological tools to flag a compound as a potential inducer of autoimmune disease or allergy are challenges for the future.
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Affiliation(s)
- C Frieke Kuper
- TNO Quality of Life, Department of Toxicology and Applied Pharmacology, P.O. Box 360, 3700 AJ Zeist, The Netherlands.
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Ruehl-Fehlert C, Bradley A, George C, Germann PG, Bolliger AP, Schultee A. Harmonization of immunotoxicity guidelines in the ICH process--pathology considerations from the guideline Committee of the European Society of Toxicological Pathology (ESTP) . ACTA ACUST UNITED AC 2005; 57:1-5. [PMID: 16089314 DOI: 10.1016/j.etp.2005.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
As part of the ICH process of harmonization of testing guidelines for immunotoxicity, the European Society of Toxicologic Pathology (ESTP) has contributed to the scientific discussion on methods and evaluation of immunotoxicity studies with technical and scientific recommendations on toxicologic pathology. The weighing and sampling of immune organs is discussed taking into consideration specifically the value of lymph node weighing and the selection of appropriate lymph nodes for the detection of local and systemic effects. The different techniques of bone marrow preparation are considered for routine and extended investigations. Criteria are given for the gross and histopathological detection of effects in Peyer's patches. For the histopathological evaluation it is strongly recommended that each compartment within the different lymphoid organs is investigated separately and semiquantitatively since this approach has shown to increase the sensitivity and specificity of immunohistopathology.
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Chu I, Bowers WJ, Caldwell D, Nakai J, Pulido O, Yagminas A, Wade MG, Moir D, Gill S, Mueller R. Toxicological Effects of Gestational and Lactational Exposure to a Mixture of Persistent Organochlorines in Rats: Systemic Effects. Toxicol Sci 2005; 88:645-55. [PMID: 16177236 DOI: 10.1093/toxsci/kfi335] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A large multi-disciplinary study was conducted to investigate the systemic, neurodevelopmental, neurochemical, endocrine, and molecular pathological effects of a mixture of reconstituted persistent organochlorine pollutants (POP) based on the blood profiles of Canadians residing in the Great Lakes/St. Lawrence region. This report outlines the overall study design and describes the systemic effects in rat offspring perinatally exposed to the POP mixture. Maternal rats were administered orally 0, 0.013, 0.13, 1.3, or 13 mg/kg bw/day of the mixture from gestational day (GD) 1 to postnatal day (PND) 23. Positive and negative controls were given Aroclor 1254 (15 mg/kg bw/day) and corn oil (vehicle), respectively. The rat pups were reared, culled to 8 per litter, and killed on postnatal days 35, 70, and 350, at which time tissues were collected for analysis. Exposure to high doses of the mixture elicited clinical, biochemical, and pathological changes and high mortality rates in rat offspring. Aroclor 1254 produced similar effects but a lower mortality than was seen in POP mixture groups. Biochemical changes consisted of increased liver microsomal activities and elevated serum cholesterol. Hepatomegaly was observed in the highest dose group of the mixture and in the positive control. Liver, thymus, and spleen were the target organs of action. Microscopic changes in the liver consisted of vacuolation and hypertrophy, and those in the thymus were characterized by reduced cortical and medullary volume. The spleen showed a treatment-related reduction in lymphocyte density and lymphoid areas. This study demonstrates that exposure to the POP mixture up to 13 mg/kg/day perinatally produced growth suppression, elevated serum cholesterol, increased liver microsomal enzyme activities, and immunopathological changes in the thymus and spleen, and lethality. Most of the effects were seen at dose levels much higher than expected human exposure.
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Affiliation(s)
- Ih Chu
- Environmental and Occupational Toxicology Division, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario.
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Affiliation(s)
- MaryJane K Selgrade
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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