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Candida bloodstream infection in patients with systemic autoimmune diseases. Med Mal Infect 2020; 50:372-376. [PMID: 32113868 DOI: 10.1016/j.medmal.2020.01.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 12/09/2019] [Accepted: 01/29/2020] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To describe the epidemiological, clinical and microbiological characteristics and mortality of patients with Candida bloodstream infection and systemic autoimmune diseases. METHODS We performed a retrospective multicenter study of candidemia in adults with systemic autoimmune diseases between 2010 and 2016. RESULTS Among 1040 patients with candidemia, 36 (3.5%) had a systemic autoimmune disease. The most common systemic autoimmune disease was rheumatoid arthritis (27.8%). The most common species was Candida albicans (66.7%). Twenty-two (61.1%) patients received a corticosteroid therapy and nine (25%) received an immunosuppressive therapy at the time of candidemia. The mortality rate was 27.8%. CONCLUSIONS Systemic autoimmune diseases are not common in patients with candidemia. The unadjusted mortality rate was comparable to other candidemia studies in the general population.
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2
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DeWitt JC, Germolec DR, Luebke RW, Johnson VJ. Associating Changes in the Immune System with Clinical Diseases for Interpretation in Risk Assessment. CURRENT PROTOCOLS IN TOXICOLOGY 2016; 67:18.1.1-18.1.22. [PMID: 26828330 PMCID: PMC4780336 DOI: 10.1002/0471140856.tx1801s67] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This overview is an update of the unit originally published in 2004. While the basic tenets of immunotoxicity have not changed in the past 10 years, several publications have explored the application of immunotoxicological data to the risk assessment process. Therefore, the goal of this unit is still to highlight relationships between xenobiotic-induced immunosuppression and risk of clinical diseases progression. In immunotoxicology, this may require development of models to equate moderate changes in markers of immune functions to potential changes in incidence or severity of infectious diseases. For most xenobiotics, exposure levels and disease incidence data are rarely available, and safe exposure levels must be estimated based on observations from experimental models or human biomarker studies. Thus, it is important to establish a scientifically sound framework that allows accurate and quantitative interpretation of experimental or biomarker data in the risk assessment process.
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Affiliation(s)
- Jamie C DeWitt
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Dori R Germolec
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, North Carolina
| | - Robert W Luebke
- Cardiopulmonary and Immunotoxicology Branch, United States Environmental Protection Agency, Research Triangle Park, North Carolina
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3
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Smith MJ, White KL. Establishment and comparison of delayed-type hypersensitivity models in the B₆C₃F₁ mouse. J Immunotoxicol 2010; 7:308-17. [PMID: 20825253 DOI: 10.3109/1547691x.2010.509707] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The objective of these studies was to establish and compare delayed-type hypersensitivity (DTH) models, using keyhole limpet hemocyanin (KLH), sheep red blood cells (SRBC), and Candida albicans as sensitizing antigens, for their capability to assess a DTH response (utilizing footpad swelling as the endpoint) with minimal confounding factors resulting from antigen-specific antibody (Ab) production. The key elements of the DTH are the sensitization dose, time interval between sensitization and challenge [i.e. the challenge interval (CI)], and the challenge dose. Models were established by first determining the challenge dose, or the amount of antigen that produced no greater footpad swelling 24-h post-injection than the trauma induced by injection of physiological saline. Time-course studies determined the CI that produced a peak response for each antigen. Dose-response sensitization studies were conducted to determine the optimum sensitization concentration (i.e. maximum footpad swelling with minimal impact by antigen-specific Ab production). Footpad swelling decreased dose-responsively with increasing KLH sensitization concentration and corresponded to a dose-responsive increase in KLH-specific Ab levels. In the SRBC model, footpad swelling decreased at the high dose (1 x 10⁹ SRBC/mouse), and a corresponding increase in SRBC-specific Ab was observed at this dose level. A dose-responsive increase in footpad swelling was observed in the C. albicans model up to 3 x 10⁷ organisms/mouse, while antigen-specific antibody levels were not different from background (unsensitized) levels following sensitization with any concentration of C. albicans (up to 1.2 x 10⁸ organisms/mouse, the highest concentration tested). Finally, each model was evaluated for its ability to detect immunosuppression following exposure to benzo[a]pyrene (B[a]P), with the C. albicans model demonstrating greater sensitivity than the other models. These results indicate that, of the three models examined here, the C. albicans DTH model may be the most appropriate model for evaluating effects on cell-mediated immunity when conducting immunotoxicological investigations.
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Affiliation(s)
- Matthew J Smith
- Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA 23298, USA
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4
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Bilitewski U. Determination of immunomodulatory effects: focus on functional analysis of phagocytes as representatives of the innate immune system. Anal Bioanal Chem 2008; 391:1545-54. [PMID: 18427788 DOI: 10.1007/s00216-008-2089-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 03/03/2008] [Accepted: 03/24/2008] [Indexed: 12/31/2022]
Abstract
The evaluation of the effects of drugs or chemicals on the functions of the immune system is an increasingly important task. Due to the accessibility of primary cells and cell lines, in vitro cellular functional tests are frequently being performed with cells representing the innate immune system, in particular those with phagocytotic activities, such as neutrophils and macrophages. Suitable functional parameters are the efficiency of phagocytosis, the efficiency with which viable pathogens are killed, the production of reactive oxygen and nitrogen species (ROS and RNS) and that of cytokines. Corresponding analytical procedures are available, but standardization is required, as varying the procedure may influence the outcomes of the assays.
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Affiliation(s)
- Ursula Bilitewski
- Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany.
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5
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Bertók L. Radio-detoxified endotoxin activates natural immunity: A review. PATHOPHYSIOLOGY 2005; 12:85-95. [PMID: 16023558 DOI: 10.1016/j.pathophys.2005.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Revised: 02/16/2005] [Accepted: 02/23/2005] [Indexed: 11/28/2022] Open
Abstract
It is well demonstrated that serial endotoxin injections produce endotoxin tolerance and elevate the natural immunity/resistance. However, such injections may also have harmful effects such as high fever, hypotension and abortion. For this reason endotoxin (LPS) injections are not suitable to enhance nonspecific resistance in endotoxin-sensitive species like man. Various techniques have been designed (physical, chemical, etc.) for the detoxification of endotoxins while the beneficial effects are maintained. Perhaps one of the best detoxification techniques is the treatment with ionizing radiation. The irradiation of LPS with 60Co (150 kGy) decreased its toxicity in a dose-dependent manner. Such radio-detoxified endotoxin (RD-LPS) preparations show decreased toxicity whereas the beneficial effects were preserved. Irradiation causes marked chemical alterations in LPS, such as a decrease of glucosamine, ketodeoxyoctonic and fatty acids. A single parenteral RD-LPS injection prevents various forms of shock in experimental animals. This preparation has a membrane-stabilizing effect, and thereby it can prevent the membrane-damaging effect of LPS and of some cytostatic agents. Unlike endotoxin, RD-LPS has little hypotensive effects, and the pretreatment with this preparation can prevent practically all the hemodynamic changes induced by LPS. LPS plays an important role in the pathogenesis of intestinal syndrome of radiation disease, which may be prevented by RD-LPS pretreatment up to 70% in rats. RD-LPS retains the adjuvant activity of LPS, and it serves as a good adjuvant for inactivated virus vaccines. RD-LPS can also evoke the regeneration of the immune system in irradiated animals. The decrease of nonspecific resistance in immunodeficient or immunosuppressed patients is the most important cause of opportunistic infections that may lead to sepsis like in endotoxaemia and pneumonia. Organ transplant recipients commonly die of septicaemia. Antilymphocyte serum (ALS) is used in such patients as an immunosuppressant. The augmentation of natural resistance and the induction of endotoxin tolerance are of major significance in such patients. In ALS-treated rats RD-LPS induces also tolerance against the lethal dose of LPS. This demonstrates that in spite of the suppressive effect of ALS on T-lymphocytes the induction of LPS tolerance (the enhancement of natural resistance) remains normal. Facultative pathogenic organisms may flourish and cause disease when specific and nonspecific resistance is impaired. RD-LPS can produce a significant proliferation of lymphoid cells in germ-free animals which are immunodeficient. Many other beneficial effects are preserved by RD-LPS preparations, such as the activation of macrophages and of the reticuloendothelial system and antitumor activity. On the basis of these favorable experimental results, RD-LPS has been tested on 350 surgical patients suffering from gastrointestinal tumors, patients suffering from acquired immunodeficiency syndrome (AIDS) and cancer patients treated with CYSPLATIN. RD-LPS treatment prevented sepsis and activated the bone marrow function in these patients.
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Affiliation(s)
- Lóránd Bertók
- Fodor József National Center of Public Health, Frédéric Joliot-Curie National Research Institute for Radiobiology and Radiohygiene, H-1221 Anna u. 5, Budapest, Hungary.
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6
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Luster MI, Germolec DR, Parks CG, Blaciforti L, Kashon M, Luebke R. Associating changes in the immune system with clinical diseases for interpretation in risk assessment. CURRENT PROTOCOLS IN TOXICOLOGY 2004; Chapter 18:Unit18.1. [PMID: 23045101 PMCID: PMC7162383 DOI: 10.1002/0471140856.tx1801s20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This overview unit discusses the relationship between immunosuppression, a potential consequence of immunotoxicity, and disease progression. It also discusses other factors, such as stress and age, that affect disease susceptibility. These factors play an important role in risk assessment for exposures to environmental factors.
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Affiliation(s)
- Michael I Luster
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV, USA
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7
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Herzyk DJ, Bugelski PJ, Hart TK, Wier PJ. Practical aspects of including functional endpoints in developmental toxicity studies. Case study: immune function in HuCD4 transgenic mice exposed to anti-CD4 MAb in utero. Hum Exp Toxicol 2002; 21:507-12. [PMID: 12458908 DOI: 10.1191/0960327102ht289oa] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Keliximab is a human-cynomolgus monkey chimeric (Primatized) monoclonal antibody with specificity for human and chimpanzee CD4. As the preclinical safety assessment of biopharmaceuticals requires evaluation in pharmacologically responsive species, comprehensive toxicology studies, including reproductive toxicity, of this antibody were conducted in a human CD4 transgenic mouse model. The reproductive toxicology studies included a pre- and postnatal development study that incorporated immunotoxicological evaluation of offspring (F1) mice. The potential effects of exposure to treating maternal mice (F0) with keliximab during pregnancy and lactation on offspring viability, physical growth, neurobehavioral development, reproductive function, lymphoid tissue morphological structure, lymphocyte subsets and host resistance to Candida albicans infection were assessed. The results showed no impairment of these functions. The use of F1 transgenic mice in study with keliximab provides an example of a novel practical approach to assess developmental immunotoxicity within a study of pre- and postnatal development designed in accordance with ICH Guidelines.
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Affiliation(s)
- D J Herzyk
- Departments of Safety Assessment, GlaxoSmithKline Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA.
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Bendel CM, Wiesner SM, Garni RM, Cebelinski E, Wells CL. Cecal colonization and systemic spread of Candida albicans in mice treated with antibiotics and dexamethasone. Pediatr Res 2002; 51:290-5. [PMID: 11861932 DOI: 10.1203/00006450-200203000-00005] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Infections with Candida albicans have become a significant problem among very low birth weight infants in the neonatal intensive care unit. Risk factors are multiple and include administration of antibiotics and glucocorticoids, such as dexamethasone. Experiments were designed to study the combined effect of oral broad-spectrum antibiotics and parenteral dexamethasone on cecal colonization and extraintestinal dissemination of C. albicans in separate groups of mice that were orally inoculated with one of four C. albicans strains that were either wild-type INT1/INT1 or had one or more disruptions of the INT1 gene. Intestinal colonization was monitored by quantitative culture of the mouse cecum, and extraintestinal invasion was monitored by quantitative culture of the draining mesenteric lymph nodes and kidneys. At sacrifice, the average numbers of cecal C. albicans differed from 7.7 log(10)/g to 6.7 log(10)/g (p < 0.01) in mice orally inoculated with C. albicans containing two functional copies of INT1 and no functional copies of INT1, respectively. The incidence of extraintestinal dissemination to mesenteric lymph nodes and kidneys correspondingly varied from 57 to 13% (p < 0.01) and 83 to 4% (p < 0.01) in mice inoculated with these two C. albicans strains. Mice orally inoculated with C. albicans containing one functional copy of INT1 had intermediate levels of cecal colonization and extraintestinal dissemination. Thus, cecal colonization and extraintestinal dissemination of C. albicans was facilitated in antibiotic-treated mice given dexamethasone. In addition, the presence of two functional copies of the INT1 gene was associated with the greatest levels of cecal colonization and extraintestinal dissemination of C. albicans.
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Affiliation(s)
- Catherine M Bendel
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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Herzyk DJ, Gore ER, Polsky R, Nadwodny KL, Maier CC, Liu S, Hart TK, Harmsen AG, Bugelski PJ. Immunomodulatory effects of anti-CD4 antibody in host resistance against infections and tumors in human CD4 transgenic mice. Infect Immun 2001; 69:1032-43. [PMID: 11160000 PMCID: PMC97984 DOI: 10.1128/iai.69.2.1032-1043.2001] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Anti-CD4 antibodies, which cause CD4(+) T-cell depletion, have been shown to increase susceptibility to infections in mice. Thus, development of anti-CD4 antibodies for clinical use raises potential concerns about suppression of host defense mechanisms against pathogens and tumors. The anti-human CD4 antibody keliximab, which binds only human and chimpanzee CD4, has been evaluated in host defense models using murine CD4 knockout-human CD4 transgenic (HuCD4/Tg) mice. In these mice, depletion of CD4(+) T cells by keliximab was associated with inhibition of anti-Pneumocystis carinii and anti-Candida albicans antibody responses and rendered HuCD4/Tg mice susceptible to P. carinii, a CD4-dependent pathogen, but did not compromise host defense against C. albicans infection. Treatment of HuCD4/Tg mice with corticosteroids impaired host immune responses and decreased survival for both infections. Resistance to experimental B16 melanoma metastases was not affected by treatment with keliximab, in contrast to an increase in tumor colonization caused by anti-T cell Thy1.2 and anti-asialo GM-1 antibodies. These data suggest an immunomodulatory rather than an overt immunosuppressive activity of keliximab. This was further demonstrated by the differential effect of keliximab on type 1 and type 2 cytokine expression in splenocytes stimulated ex vivo. Keliximab caused an initial up-regulation of interleukin-2 (IL-2) and gamma interferon, followed by transient down-regulation of IL-4 and IL-10. Taken together, the effects of keliximab in HuCD4/Tg mice suggest that in addition to depleting circulating CD4(+) T lymphocytes, keliximab has the capability of modulating the function of the remaining cells without causing general immunosuppression. Therefore, keliximab therapy may be beneficial in controlling certain autoimmune diseases.
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Affiliation(s)
- D J Herzyk
- Department of Safety Assessment, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA.
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10
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Bugelski PJ, Herzyk DJ, Rehm S, Harmsen AG, Gore EV, Williams DM, Maleeff BE, Badger AM, Truneh A, O'Brien SR, Macia RA, Wier PJ, Morgan DG, Hart TK. Preclinical development of keliximab, a Primatized anti-CD4 monoclonal antibody, in human CD4 transgenic mice: characterization of the model and safety studies. Hum Exp Toxicol 2000; 19:230-43. [PMID: 10918514 DOI: 10.1191/096032700678815783] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The preclinical safety assessment of biopharmaceuticals necessitates that studies be conducted in species in which the products are pharmacologically active. Monoclonal antibodies are a promising class of biopharmaceuticals for many disease indications; however, by design, these agents tend to have limited species cross-reactivity and tend to only be active in primates. Keliximab is a human-cynomolgus monkey chimeric (Primatized) monoclonal antibody with specificity for human and chimpanzee CD4. In order to conduct a comprehensive preclinical safety assessment of this antibody to support chronic treatment of rheumatoid arthritis in patients, a human CD4 transgenic mouse was used for chronic and reproductive toxicity studies and for genotoxic studies. In addition, immunotoxicity studies were conducted in these mice with Candida albicans, Pneumocystis carinii and B16 melanoma cells to assess the effects of keliximab on host resistance to infection and immunosurveillance to neoplasia. The results of these studies found keliximab to be well tolerated with the only effects observed being related to its pharmacologic activity on CD4+ T lymphocytes. The use of transgenic mice expressing human proteins provides a useful alternative to studies in chimpanzees with biopharmaceutical agents having limited species cross-reactivity.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/toxicity
- Antibody Formation/drug effects
- CD4 Antigens/immunology
- CHO Cells
- Candidiasis/immunology
- Cricetinae
- Drug Evaluation, Preclinical
- Female
- Flow Cytometry
- Humans
- Hypersensitivity, Delayed/immunology
- Immune System/growth & development
- In Situ Hybridization, Fluorescence
- Lymphocyte Culture Test, Mixed
- Male
- Melanoma, Experimental/drug therapy
- Melanoma, Experimental/pathology
- Mice
- Mice, SCID
- Mice, Transgenic
- Micronucleus Tests
- Pneumocystis Infections/immunology
- Reproduction/drug effects
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Affiliation(s)
- P J Bugelski
- Department of Safety Assessment, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA
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Badger AM, Handler JA, Genell CA, Herzyk D, Gore E, Polsky R, Webb L, Bugelski PJ. Atiprimod (SK&F 106615), a novel macrophage targeting agent, enhances alveolar macrophage candidacidal activity and is not immunosuppressive in Candida-infected mice. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1999; 21:161-76. [PMID: 10348366 DOI: 10.1016/s0192-0561(98)00076-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Azaspiranes are novel macrophage-targeting agents with activity in preclinical animal models of autoimmune disease and transplantation. The purpose of this work was to determine the effects of atiprimod (SK&F 106615), an azaspirane being developed for the treatment of rheumatoid arthritis, on rat pulmonary alveolar macrophage (AM) function and immunocompetance in Candida-infected mice. AM from rats treated with 20 mg/kg/day of atiprimod for 15 days demonstrated enhanced killing of Candida albicans ex vivo. Concentration-dependent increases in candidacidal activity were also observed as early as one hour after exposure in vitro in AM from untreated normal rats. Treatment of AM with atiprimod in vitro did not increase particulate-stimulated superoxide production or phagocytosis of Candida but decreased their ability to concentrate acridine orange, indicating an increase in lysosomal pH. Increased candidacidal activity was inhibited by superoxide dismutase and catalase, suggesting a role for reactive oxygen intermediates (ROI). Atiprimod also increased free radical-mediated killing of Candida in the presence of H2O2, iron and iodide in a cell-free system. These findings indicated that treatment with atiprimod increased the candidacidal activity of rat AM in a free radical-dependent manner. The data also suggested that atiprimod did not increase ROI production by AM, but rather increased the efficiency of radical-mediated killing. This increase may be caused by cyclization of atiprimod, facilitating electron transfer and peroxidation of lipid membranes. In vivo studies in Candida-infected CBA mice showed that atiprimod (10 mg/kg/day), did not compromise immune function in the infected mice and could be differentiated from prototypical immunosuppressive compounds used for treatment of autoimmune diseases.
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Affiliation(s)
- A M Badger
- Department of Bone and Cartilage Biology, Smith Kline Beecham Pharmaceuticals Research and Development, King of Prussia, PA 19406-0939, USA
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Abstract
The ultimate goal of any animal model in immunotoxicity testing is that it be a sensitive predictor of xenobiotic-induced immune dysfunction in humans. Such models should be capable of identifying the target(s) within the immune system affected by the xenobiotic. In particular the tier testing models have been successfully used to identify and characterize a variety of different immunotoxicants in animals as it pertains to immunosuppression and reduced resistance to infectious diseases. These tier models in mice and rats have been validated in interlaboratory studies. Although these protocols were designed for studies of rats and mice, some have been applied successfully for studying immunotoxicity in other animal species, including non-human primates. A great amount of data has been generated by the application of these models, which demonstrate that xenobiotics alter the immune system of animals. In man, the database on chemical-induced immunosuppression is limited, as the use of markers of immunotoxicity has received little attention in clinical and epidemiological studies. Such studies have not been performed frequently, and their interpretation often does not permit unequivocal conclusions to be drawn, due for instance to the presence of confounding factors and the uncontrolled nature of exposure. Also, testing possibilities in humans are limited and immune function changes by chemical exposure are often subtle. In humans, a number of agents have been shown to have immunosuppressive properties (including PCBs, PCDDs, PCDFs, oxidant gases, and ultraviolet radiation), but the strongest evidence stems from the clinical use of immunosuppressant drugs in transplant patients. These human data do in general terms confirm the data gained with experimental animals. Immunotoxicity assessment in rodents therefore adequately forms the basis for human risk assessment. Knowledge on the predictability of these animal models and immune assays can be further improved by comparison of the human and animal data obtained in the development of drugs.
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Affiliation(s)
- J G Vos
- Laboratory for Pathology and Immunobiology, National Institute of Public Health and the Environment, Bilthoven, The Netherlands
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14
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Bertram TA. Assessment of altered immune status induced by immunomodulatory drugs via an apical test in mice. Toxicol Pathol 1997; 25:419-20. [PMID: 9280131 DOI: 10.1177/019262339702500417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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