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Fujimoto K, Higaki T, Abe J, Fujita M, Kawakami T. Theoretical Validation of In Chemico Skin Sensitization Assay "ADRA" Using the Products Formed by Nucleophilic Reagents and Chemicals. Chem Res Toxicol 2022; 35:2107-2121. [PMID: 36315617 DOI: 10.1021/acs.chemrestox.2c00228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Amino acid derivative reactivity assay (ADRA) is an in chemico assay for assessing the skin sensitization potential of chemicals by evaluating the reactivity of nucleophilic reagents that mimic skin proteins. N-(2-(1-Naphthyl)acetyl)-l-cysteine (NAC) and α-N-(2-(1-naphthyl)acetyl)-l-lysine (NAL), used as nucleophilic reagents, are small-molecule derivatives of two different amino acids, each with a naphthalene ring attached. The rate of decrease in the amount of NAC or NAL in the reaction solution is evaluated in this assay as an indicator of the test substance's skin sensitization ability. However, the products formed between the nucleophilic reagent and the test substance, which play an important role in vivo, are not directly identified. Therefore, six highly reactive chemicals, including the proficiency substances listed in the OECD Test Guidelines─squaric acid diethyl ester, 2-methyl-2H-isothiazol-3-one (MI), p-benzoquinone, palmitoyl chloride, diphenylcyclopropenone (DPCP), and imidazolidinyl urea (IU)─were used to determine each formed product. Samples were prepared according to the standard ADRA method, and the formed products were predicted on the basis of the reaction mechanism. Excluding DPCP, the estimated structures were validated using mass spectrometry and nuclear magnetic resonance spectrometry on the synthesized samples. In this manner, the products of each nucleophile were confirmed for all examined test substances. The estimated structure products were obtained through a series of reactions initiated by the nucleophilic attack of NAC's thiol group or NAL's amino group on the test substance's electron-deficient carbonyl carbon. However, contrary to expectations, disulfide-linked-type ring-opened products were detected in the case of MI, and products with free formaldehyde in solution were detected in the case of IU. In summary, all skin sensitizers tested herein reacted with NAC and/or NAL to give products. This supports the theoretical validity of ADRA, which provides an indirect evaluation of the formed products based on a decrease in nucleophilic reagents.
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Affiliation(s)
- Keiichi Fujimoto
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 1-98, Kasugade-Naka 3-Chome, Konohana-Ku, Osaka City 554-8558, Osaka, Japan
| | - Tamaki Higaki
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 1-98, Kasugade-Naka 3-Chome, Konohana-Ku, Osaka City 554-8558, Osaka, Japan
| | - Jun Abe
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 1-98, Kasugade-Naka 3-Chome, Konohana-Ku, Osaka City 554-8558, Osaka, Japan
| | - Masaharu Fujita
- Safety Evaluation Center, FUJIFILM Corporation, 210, Nakanuma, Minamiashigara 250-0193, Kanagawa, Japan
| | - Tsuyoshi Kawakami
- Division of Environmental Chemistry, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Kanagawa, Japan
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2
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Tokunaga T, Yamamoto G, Takahashi T, Mukumoto M, Sato M, Okamoto M. Sensitive Method for the Identification of Potential Sensitizing Impurities in Reaction Mixtures by Fluorescent Nitrobenzoxadiazole-Labeled Glutathione. Chem Res Toxicol 2020; 33:3001-3009. [PMID: 33256404 DOI: 10.1021/acs.chemrestox.0c00327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Allergic contact dermatitis is a critical issue in the development of new chemicals. Minor impurities with strong skin-sensitizing properties can be generated as byproducts. However, it is very difficult to identify these skin sensitizers in product mixtures. In this study, fluorescent nitrobenzoxadiazole-labeled glutathione (NBD-GSH) was synthesized to identify small amounts of skin sensitizers in reaction mixtures. Twelve known skin sensitizers and three nonsensitizers were reacted with NBD-GSH. Adducts formed only with the skin sensitizers, which allowed for their detection by a fluorescence detector. Liquid chromatography-mass spectrometry (LC-MS) analyses showed that NBD-GSH reacted with the skin sensitizers via its thiol and amino groups. An adduct of NBD-GSH with the strong skin sensitizer 1-chloro-2,4-dinitrobenzene was detected with a limit of detection of 6 × 10-8 mol/L by high-performance liquid chromatography with fluorescence detection. When a reaction mixture from primary alcohol oxidation was incubated with NBD-GSH, a NBD-GSH adduct formed with skin-sensitizing aldehyde impurities and could be specifically detected by LC-MS with fluorescence detection. This method will be useful for detection and identification of small amounts of skin sensitizers in raw materials, intermediates, reaction mixtures, and end products in the chemical industry.
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Affiliation(s)
- Takashi Tokunaga
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
| | - Gaku Yamamoto
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
| | - Teruki Takahashi
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
| | - Makiko Mukumoto
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
| | - Masayuki Sato
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
| | - Masahiko Okamoto
- Environmental Health Science Laboratory, Sumitomo Chemical Co., Ltd., 3-1-98 Kasugadenaka, Konohana-ku, Osaka 554-8558, Japan
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3
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Nakagawa S, Okamoto M, Nukada Y, Morita O. Comparison of the potential mechanisms for hepatotoxicity of p-dialkoxy chlorobenzenes in rat primary hepatocytes for read-across. Regul Toxicol Pharmacol 2020; 113:104617. [PMID: 32087351 DOI: 10.1016/j.yrtph.2020.104617] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 12/26/2019] [Accepted: 02/18/2020] [Indexed: 01/06/2023]
Abstract
Read-across based on only structural similarity is considered to have a risk of error in chemical risk assessment. Under these circumstances, considering biological similarity based on adverse outcome pathways using in vitro omics technologies is expected to enhance the accuracy and robustness of conclusions in read-across. However, due to a lack of practical case studies, key considerations and use of these technologies for data gap filling are not well discussed. Here we extracted and compared the potential mechanisms for hepatotoxicity for structural analogs of p-dialkoxy chlorobenzenes including 1,4-dichloro-2,5-dimethoxybenzene (DDMB), 2,5-dichloro-1,4-diethoxybenzene (DDEB), 2-chloro-1,4-dimethoxybenzene (CDMB), and 1-chloro-2,5-diethoxybenzene (CDEB) using in vitro omics technologies for read-across. To reveal the potential mechanisms for hepatotoxicity, we conducted microarray analysis with rat primary hepatocytes. The results showed that three (DDMB, DDEB, CDEB) of the four chemicals affected similar biological pathways such as peroxisome proliferation, oxidative stress, and mitochondrial dysfunction. Furthermore, these biological pathways are consistent with in vivo hepatotoxicity in the source chemical, DDMB. In contrast, CDMB did not affect a specific toxicological pathway. Taken together, these data show the potential mechanisms for hepatotoxicity for three chemicals (DDMB, DDEB, CDEB) and provide novel insights into grouping chemicals using in vitro toxicogenomics for read-across.
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Affiliation(s)
- Shota Nakagawa
- Kao Corporation, Safety Science Research, 2606, Akabane, Ichikai-Machi, Haga-Gun Tochigi, 321-3497, Japan.
| | - Maiko Okamoto
- Kao Corporation, Safety Science Research, 2606, Akabane, Ichikai-Machi, Haga-Gun Tochigi, 321-3497, Japan
| | - Yuko Nukada
- Kao Corporation, Safety Science Research, 2606, Akabane, Ichikai-Machi, Haga-Gun Tochigi, 321-3497, Japan
| | - Osamu Morita
- Kao Corporation, Safety Science Research, 2606, Akabane, Ichikai-Machi, Haga-Gun Tochigi, 321-3497, Japan
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4
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Höper T, Mussotter F, Haase A, Luch A, Tralau T. Application of proteomics in the elucidation of chemical-mediated allergic contact dermatitis. Toxicol Res (Camb) 2017; 6:595-610. [PMID: 30090528 PMCID: PMC6062186 DOI: 10.1039/c7tx00058h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/07/2017] [Indexed: 12/23/2022] Open
Abstract
Allergic contact dermatitis (ACD) is a widespread hypersensitivity reaction of the skin. The cellular mechanisms underlying its development are complex and involve close interaction of different cell types of the immune system. It is this very complexity which has long prevented straightforward replacement of the corresponding regulatory in vivo tests. Recent efforts have already resulted in the development of several in vitro testing alternatives that address key steps of ACD. Yet identification of suitable biomarkers is still a subject of intense research. Search strategies for the latter encompass transcriptomics, proteomics as well as metabolomics approaches. The scope of this review shall be the application and use of proteomics in the context of ACD. This includes highlighting relevant aspects of the molecular and cellular mechanisms underlying ACD, the exploitation of these mechanisms for testing and biomarkers (e.g., in the context of the OECD's adverse outcome pathway initiative) as well as an outlook on emerging proteome targets, for example during the allergen-induced activation of dendritic cells (DCs).
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Affiliation(s)
- Tessa Höper
- German Federal Institute for Risk Assessment , Department of Chemical and Product Safety , Max-Dohrn-Strasse 8-10 , 10589 Berlin , Germany .
| | - Franz Mussotter
- German Federal Institute for Risk Assessment , Department of Chemical and Product Safety , Max-Dohrn-Strasse 8-10 , 10589 Berlin , Germany .
| | - Andrea Haase
- German Federal Institute for Risk Assessment , Department of Chemical and Product Safety , Max-Dohrn-Strasse 8-10 , 10589 Berlin , Germany .
| | - Andreas Luch
- German Federal Institute for Risk Assessment , Department of Chemical and Product Safety , Max-Dohrn-Strasse 8-10 , 10589 Berlin , Germany .
| | - Tewes Tralau
- German Federal Institute for Risk Assessment , Department of Chemical and Product Safety , Max-Dohrn-Strasse 8-10 , 10589 Berlin , Germany .
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5
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Gerberick GF. The use of peptide reactivity assays for skin sensitisation hazard identification and risk assessment. Altern Lab Anim 2017; 44:437-442. [PMID: 27805826 DOI: 10.1177/026119291604400506] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Over the past 20 years or more, investigators have been developing non-animal test methods for use in assessing the skin sensitisation potential of chemicals. In parallel with this effort, the key biological events of skin sensitisation have been well-characterised in an Adverse Outcome Pathway (AOP) proposed by the Organisation for Economic Co-operation and Development (OECD). The key molecular initiating event of this AOP is haptenation or covalent modification of epidermal proteins. In this review, the strengths and limitations of the Direct Peptide Reactivity Assay (DPRA) are described, and the more recently developed Peroxidase Peptide Reactivity Assay (PPRA). The DPRA has been formally validated and incorporated into an OECD Test Guideline (TG442C). The DPRA shows promise for assisting in hazard identification as well as for assessing skin sensitisation potency when used in an integrated testing strategy.
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Affiliation(s)
- G Frank Gerberick
- The Procter & Gamble Company, Mason Business Center, Cincinnati, OH, USA
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6
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Natsch A, Emter R. Reaction Chemistry to Characterize the Molecular Initiating Event in Skin Sensitization: A Journey to Be Continued. Chem Res Toxicol 2016; 30:315-331. [DOI: 10.1021/acs.chemrestox.6b00365] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Andreas Natsch
- Biosciences, Givaudan Schweiz AG, Ueberlandstrasse 138, CH-8600 Duebendorf, Switzerland
| | - Roger Emter
- Biosciences, Givaudan Schweiz AG, Ueberlandstrasse 138, CH-8600 Duebendorf, Switzerland
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7
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Debeuckelaere C, Berl V, Elbayed K, Moussallieh FM, Namer IJ, Lepoittevin JP. Matrix Effect of Human Reconstructed Epidermis on the Chemoselectivity of a Skin Sensitizing α-Methylene-γ-Butyrolactone: Consequences for the Development of in Chemico Alternative Methods. Chem Res Toxicol 2015; 28:2192-8. [DOI: 10.1021/acs.chemrestox.5b00363] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Camille Debeuckelaere
- Institute
of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue
Blaise Pascal, 67081 Strasbourg, France
| | - Valérie Berl
- Institute
of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue
Blaise Pascal, 67081 Strasbourg, France
| | - Karim Elbayed
- Institute
of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue
Blaise Pascal, 67081 Strasbourg, France
- Laboratoire
des sciences de l’ingénieur, de l’informatique
et de l’imagerie (ICube), CNRS UMR 7357 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - François-Marie Moussallieh
- Institute
of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue
Blaise Pascal, 67081 Strasbourg, France
- Laboratoire
des sciences de l’ingénieur, de l’informatique
et de l’imagerie (ICube), CNRS UMR 7357 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - Izzie-Jacques Namer
- Laboratoire
des sciences de l’ingénieur, de l’informatique
et de l’imagerie (ICube), CNRS UMR 7357 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - J.-P. Lepoittevin
- Institute
of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue
Blaise Pascal, 67081 Strasbourg, France
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8
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Rehema A, Kullisaar T, Seer K, Reinmann K, Zilmer M, Kilk K. Proteomic proof that a probiotic elevates glutathione level in human serum. Open Life Sci 2015. [DOI: 10.1515/biol-2015-0021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AbstractLactobacillus fermentum ME-3 (LfME-3) has been
proven to synthesize and secrete glutathione. A regular
use of the foods fermented by it has shown a favourable
influence on human lipid profiles and several antioxidant
parameters. We administered the LfME-3-fermented kefir
for 14 days to 43 human subjects and evaluated their serum
with MALDI-TOF mass spectrometer at the beginning and
end of the test period. We found an increase of the peak at
m/z 308 (corresponding to glutathione) and a new peak
at m/z 1467.
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Affiliation(s)
- Aune Rehema
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
| | - Tiiu Kullisaar
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
| | - Kärt Seer
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
| | - Kristen Reinmann
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
| | - Mihkel Zilmer
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
| | - Kalle Kilk
- 1Tartu University Medical Faculty Department of Biochemistry 50411 Tartu, Ravila st. 19, Estonia
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9
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Salapovic H, Geier J, Reznicek G. Quantification of Sesquiterpene Lactones in Asteraceae Plant Extracts: Evaluation of their Allergenic Potential. Sci Pharm 2013; 81:807-18. [PMID: 24106675 PMCID: PMC3791941 DOI: 10.3797/scipharm.1306-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 08/15/2013] [Indexed: 11/23/2022] Open
Abstract
Sesquiterpene lactones (SLs), mainly those with an activated exocyclic methylene group, are important allergens in Asteraceae (Compositae) plants. As a screening tool, the Compositae mix, consisting of five Asteraceae plant extracts with allergenic potential (feverfew, tansy, arnica, yarrow, and German chamomile) is part of several national patch test baseline series. However, the SL content of the Compositae mix may vary due to the source material. Therefore, a simple spectrophotometric method for the quantitative measurement of SLs with the α-methylene-γ-butyrolactone moiety was developed, giving the percentage of allergenic compounds in plant extracts. The method has been validated and five Asteraceae extracts, namely feverfew (Tanacetum parthenium L.), tansy (Tanacetum vulgare L.), arnica (Arnica montana L.), yarrow (Achillea millefolium L.), and German chamomile (Chamomilla recutita L. Rauschert) that have been used in routine patch test screening were evaluated. A good correlation could be found between the results obtained using the proposed spectrophotometric method and the corresponding clinical results. Thus, the introduced method is a valuable tool for evaluating the allergenic potential and for the simple and efficient quality control of plant extracts with allergenic potential.
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In chemico evaluation of prohapten skin sensitizers: Behavior of 2-methoxy-4-(13C)methylphenol in the peroxidase peptide reactivity assay (PPRA) as an alternative to animal testing. Toxicol Lett 2013; 218:266-72. [DOI: 10.1016/j.toxlet.2013.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 02/18/2013] [Accepted: 02/19/2013] [Indexed: 11/15/2022]
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11
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Lalko J, Dearman R, Gerberick G, Troutman J, Api A, Kimber I. Reactivity of chemical respiratory allergens in the Peroxidase Peptide Reactivity Assay. Toxicol In Vitro 2013; 27:651-61. [DOI: 10.1016/j.tiv.2012.10.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/05/2012] [Accepted: 10/29/2012] [Indexed: 11/28/2022]
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12
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Elbayed K, Berl V, Debeuckelaere C, Moussallieh FM, Piotto M, Namer IJ, Lepoittevin JP. HR-MAS NMR Spectroscopy of Reconstructed Human Epidermis: Potential for the in Situ Investigation of the Chemical Interactions between Skin Allergens and Nucleophilic Amino Acids. Chem Res Toxicol 2013; 26:136-45. [DOI: 10.1021/tx300428u] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Karim Elbayed
- Institute of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - Valérie Berl
- Institute of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - Camille Debeuckelaere
- Institute of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
| | - François-Marie Moussallieh
- Institute of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
- Department of Biophysics and Nuclear Medicine, Strasbourg University Hospital, 67098 Strasbourg, France
| | | | - Izzie-Jacques Namer
- Department of Biophysics and Nuclear Medicine, Strasbourg University Hospital, 67098 Strasbourg, France
- Institute of Biological Physics, Faculty of Medicine, LINC/CNRS UMR 7237 and University of Strasbourg, 67085 Strasbourg, France
| | - Jean-Pierre Lepoittevin
- Institute of Chemistry, CNRS UMR 7177 and University of Strasbourg, 4 rue Blaise Pascal, 67081 Strasbourg, France
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13
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Sibille E, Bana E, Chaouni W, Diederich M, Bagrel D, Chaimbault P. Development of a matrix-assisted laser desorption/ionization–mass spectrometry screening test to evidence reversible and irreversible inhibitors of CDC25 phosphatases. Anal Biochem 2012; 430:83-91. [DOI: 10.1016/j.ab.2012.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 07/26/2012] [Accepted: 08/08/2012] [Indexed: 10/28/2022]
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14
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Lalko JF, Kimber I, Dearman RJ, Api AM, Gerberick GF. The selective peptide reactivity of chemical respiratory allergens under competitive and non-competitive conditions. J Immunotoxicol 2012; 10:292-301. [PMID: 23050863 DOI: 10.3109/1547691x.2012.725784] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
It is well established that certain chemicals cause respiratory allergy. In common with contact allergens, chemicals that induce sensitization of the respiratory tract must form stable associations with host proteins to elicit an immune response. Measurement of the reactivity of chemical allergens to single nucleophilic peptides is increasingly well-described, and standardized assays have been developed for use in hazard assessment. This study employed standard and modified peptide reactivity assays to investigate the selectivity of chemical respiratory allergens for individual amino acids under competitive and non-competitive conditions. The reactivity of 20 known chemical respiratory sensitizers (including diisocyanates, anhydrides, and reactive dyes) were evaluated for reactivity towards individual peptides containing cysteine, lysine, histidine, arginine, or tyrosine. Respiratory allergens exhibited the common ability to deplete both lysine and cysteine peptides; however, reactivity for histidine, arginine, and tyrosine varied between chemicals, indicating differences in relative binding affinity toward each nucleophile. To evaluate amino acid selectivity for cysteine and lysine under competitive conditions a modified assay was used in which reaction mixtures contained different relative concentrations of the target peptides. Under these reaction conditions, the binding preferences of reference respiratory and contact allergens (dinitrochlorobenzene, dinitrofluorobenzene) were evaluated. Discrete patterns of reactivity were observed showing various levels of competitive selectivity between the two allergen classes.
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Affiliation(s)
- Jon F Lalko
- Research Institute for Fragrance Materials Inc., Woodcliff Lake, NJ 07677, USA.
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15
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16
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Troutman JA, Foertsch LM, Kern PS, Dai HJ, Quijano M, Dobson RL, Lalko JF, Lepoittevin JP, Gerberick GF. The Incorporation of Lysine into the Peroxidase Peptide Reactivity Assay for Skin Sensitization Assessments. Toxicol Sci 2011; 122:422-36. [DOI: 10.1093/toxsci/kfr101] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Chemical reactivity measurements: Potential for characterization of respiratory chemical allergens. Toxicol In Vitro 2011; 25:433-45. [DOI: 10.1016/j.tiv.2010.11.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 10/01/2010] [Accepted: 11/11/2010] [Indexed: 01/13/2023]
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18
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Merckel F, Bernard G, Mutschler J, Giménez-Arnau E, Gerberick GF, Lepoittevin JP. Effect of a Microemulsion System on Hapten-Peptide Reactivity Studies: Examples of Hydroxycitronellal and Citral, Fragrance Skin Sensitizers, with Glutathione. Chem Res Toxicol 2010; 23:1433-41. [DOI: 10.1021/tx100043b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Fabien Merckel
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
| | - Guillaume Bernard
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
| | - Julien Mutschler
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
| | - Elena Giménez-Arnau
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
| | - G. Frank Gerberick
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
| | - Jean-Pierre Lepoittevin
- Laboratoire de Dermatochimie, Institut de Chimie, CNRS and Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France, and Central Product Safety, Miami Valley Innovation Center, The Procter & Gamble Company, Cincinnati, Ohio 45253
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19
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McKim JM, Keller DJ, Gorski JR. A newin vitromethod for identifying chemical sensitizers combining peptide binding with ARE/EpRE-mediated gene expression in human skin cells. Cutan Ocul Toxicol 2010; 29:171-92. [DOI: 10.3109/15569527.2010.483869] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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20
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ANZAI T, ULLMANN LG, HAYASHI D, SATOH T, KUMAZAWA T, SATO K. Effects of Strain Differences and Vehicles on Results of Local Lymph Node Assays. Exp Anim 2010; 59:245-9. [DOI: 10.1538/expanim.59.245] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
- Takayuki ANZAI
- Showa University School of Medicine
- Harlan Laboratories Ltd
| | | | | | - Tetsuo SATOH
- HAB Research Institute, Ichikawa General Hospital
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Carmichael P, Davies M, Dent M, Fentem J, Fletcher S, Gilmour N, MacKay C, Maxwell G, Merolla L, Pease C, Reynolds F, Westmoreland C. Non-Animal Approaches for Consumer Safety Risk Assessments: Unilever's Scientific Research Programme. Altern Lab Anim 2009; 37:595-610. [DOI: 10.1177/026119290903700605] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Non-animal based approaches to risk assessment are now routinely used for assuring consumer safety for some endpoints (such as skin irritation) following considerable investment in developing and applying new methods over the past 20 years. Unilever's research programme into non-animal approaches for safety assessment is currently focused on the application of new technologies to risk assessments in the areas of skin allergy, cancer and general toxicity (including inhalation toxicity). In all of these areas, a long-term investment is essential to increase the scientific understanding of the underlying biological and chemical processes that we believe will ultimately form a sound basis for novel risk assessment approaches. Our research programme in these priority areas consists of in-house research as well as Unilever-sponsored academic research, involvement with EU-funded projects (e.g. Sens-it-iv, carcino-GENOMICS), participation in cross-industry collaborative research (e.g. COLIPA, EPAA) and ongoing involvement with other scientific initiatives on non-animal approaches to risk assessment (e.g. UK NC3Rs, US ‘Human Toxicology Project’ consortium).
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Affiliation(s)
- Paul Carmichael
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Michael Davies
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Matt Dent
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Julia Fentem
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Samantha Fletcher
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Nicola Gilmour
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Cameron MacKay
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Gavin Maxwell
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Leona Merolla
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Camilla Pease
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Fiona Reynolds
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
| | - Carl Westmoreland
- Safety & Environmental Assurance Centre (SEAC), Unilever, Colworth Science Park, Sharnbrook, Bedford, UK
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22
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Pham TTP, Oyama T, Isse T, Kawamoto T. Application of tryptophan fluorescence to assess sensitizing potentials of chemicals. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 57:427-436. [PMID: 19247567 DOI: 10.1007/s00244-009-9297-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 02/09/2009] [Indexed: 05/27/2023]
Abstract
There are too many chemical substances around our living space. However, the toxicity of most of them has not been reported, especially regarding their sensitizing potentials. We aimed to develop a simple in vitro method to quantitatively predict the sensitizing potentials of chemicals by measuring the fluorescence of chemical-human serum albumin (HSA) complexes. HSA was treated with test chemicals and then analyzed by tryptophan fluorescence and protein concentration measurement. Four commonly designated sensitizers, two possible sensitizers, and two nonsensitizers were examined using the tryptophan fluorescence assay. HSA fluorescence at 280 nm excitation and 340 nm emission was reduced by toluene 2,4-diisocyanate (TDI), dose dependently. The addition of TDI immediately reduced the fluorescence, and it was stable for 6 h to 21 days after treatment, with a slight decrease. The reduction of HSA fluorescence by chemicals was in the order: commonly designated sensitizers > possible sensitizers > nonsensitizers. Chemical treatment at 0.05 and 0.5 mM led to optimal separation among the three groups. o-Phthalaldehyde (OPA), which has not been evaluated regarding its sensitization potential by any of the authorized organizations, reduced HSA fluorescence as much as the commonly designated sensitizer at final concentrations of the chemical of 0.05 and 0.5 mM. According to our method, OPA is evaluated as a commonly designated sensitizer. The treatment of all test chemicals did not lead to marked differences in the total protein concentrations by either the Lowry or the Bradford method. The assay utilizing tryptophan fluorescence loss of HSA after chemical treatment is a promising method to evaluate the sensitizing potentials of chemicals.
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Affiliation(s)
- Thi-Thu-Phuong Pham
- Department of Environmental Health, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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23
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Gerberick GF, Troutman JA, Foertsch LM, Vassallo JD, Quijano M, Dobson RLM, Goebel C, Lepoittevin JP. Investigation of Peptide Reactivity of Pro-hapten Skin Sensitizers Using a Peroxidase-Peroxide Oxidation System. Toxicol Sci 2009; 112:164-74. [DOI: 10.1093/toxsci/kfp192] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Aleksic M, Thain E, Roger D, Saib O, Davies M, Li J, Aptula A, Zazzeroni R. Reactivity profiling: covalent modification of single nucleophile peptides for skin sensitization risk assessment. Toxicol Sci 2009; 108:401-11. [PMID: 19221146 DOI: 10.1093/toxsci/kfp030] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The molecular basis of chemical allergy is rooted in the ability of an allergen (hapten) to modify endogenous proteins. This mechanistic understanding aided development of screening assays which generate reproducible quantitative and qualitative reactivity data. Such assays use model peptides with a limited number and type of protein nucleophiles, and the data does not reflect the specificity, variety, and complexity of hapten interactions with multiple nucleophiles. Building on these developments, we extended the standardized approach to maximize the type and the amount of information that can be derived from an in chemico assay. We used a panel of six single nucleophile peptides and individually optimized the incubation conditions to favor chemical modification. Employing liquid chromatography tandem mass spectrometry (LC-MS/MS) technique, we simultaneously obtained multiple quantitative and qualitative measurements (% peptide depletion, adducts formation, and peptide dimerization for Cys-containing peptide). Using these methods, we obtained reactivity data for 36 chemicals of known skin sensitizing potency. By optimizing incubation conditions, we ensured detection of all reactive chemicals. We explored the LC-MS/MS approach to generate kinetic data for 10 chemicals allowing further characterization of reactivity and a potentially more robust quantitative reactivity descriptor. Our ultimate aim is to integrate this dataset with available physicochemical data and outputs from other predictive assays, all addressing different key steps in the induction of sensitization, to help us make decisions about the safe use of chemicals without using animal tests. The epidermal protein target sites, modification of which may be immunogenic and lead to induction of skin sensitization, are currently unknown. Increasing the understanding of this process may help further refine in chemico reactivity assays as well as aid the interpretation of the reactivity data.
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Affiliation(s)
- Maja Aleksic
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, Bedford, UK.
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Assuring Consumer Safety without Animal Testing: A Feasibility Case Study for Skin Sensitisation. Altern Lab Anim 2008; 36:557-68. [DOI: 10.1177/026119290803600511] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Allergic Contact Dermatitis (ACD; chemical-induced skin sensitisation) represents a key consumer safety endpoint for the cosmetics industry. At present, animal tests (predominantly the mouse Local Lymph Node Assay) are used to generate skin sensitisation hazard data for use in consumer safety risk assessments. An animal testing ban on chemicals to be used in cosmetics will come into effect in the European Union (EU) from March 2009. This animal testing ban is also linked to an EU marketing ban on products containing any ingredients that have been subsequently tested in animals, from March 2009 or March 2013, depending on the toxicological endpoint of concern. Consequently, the testing of cosmetic ingredients in animals for their potential to induce skin sensitisation will be subject to an EU marketing ban, from March 2013 onwards. Our conceptual framework and strategy to deliver a non-animal approach to consumer safety risk assessment can be summarised as an evaluation of new technologies (e.g. ‘omics’, informatics), leading to the development of new non-animal ( in silico and in vitro) predictive models for the generation and interpretation of new forms of hazard characterisation data, followed by the development of new risk assessment approaches to integrate these new forms of data and information in the context of human exposure. Following the principles of the conceptual framework, we have been investigating existing and developing new technologies, models and approaches, in order to explore the feasibility of delivering consumer safety risk assessment decisions in the absence of new animal data. We present here our progress in implementing this conceptual framework, with the skin sensitisation endpoint used as a case study.
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Gerberick F, Aleksic M, Basketter D, Casati S, Karlberg AT, Kern P, Kimber I, Lepoittevin JP, Natsch A, Ovigne JM, Rovida C, Sakaguchi H, Schultz T. Chemical reactivity measurement and the predicitve identification of skin sensitisers. The report and recommendations of ECVAM Workshop 64. Altern Lab Anim 2008; 36:215-42. [PMID: 18522487 DOI: 10.1177/026119290803600210] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Frank Gerberick
- Procter & Gamble Company, Miami Valley Innovation Center, Cincinnati, OH 45253, USA.
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Bernstein IL, Li JT, Bernstein DI, Hamilton R, Spector SL, Tan R, Sicherer S, Golden DBK, Khan DA, Nicklas RA, Portnoy JM, Blessing-Moore J, Cox L, Lang DM, Oppenheimer J, Randolph CC, Schuller DE, Tilles SA, Wallace DV, Levetin E, Weber R. Allergy diagnostic testing: an updated practice parameter. Ann Allergy Asthma Immunol 2008; 100:S1-148. [PMID: 18431959 DOI: 10.1016/s1081-1206(10)60305-5] [Citation(s) in RCA: 291] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Karlberg AT, Bergström MA, Börje A, Luthman K, Nilsson JLG. Allergic contact dermatitis--formation, structural requirements, and reactivity of skin sensitizers. Chem Res Toxicol 2007; 21:53-69. [PMID: 18052130 DOI: 10.1021/tx7002239] [Citation(s) in RCA: 197] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Contact allergy is caused by a wide range of chemicals after skin contact. Its clinical manifestation, allergic contact dermatitis (ACD), is developed upon repeated contact with the allergen. This perspective focuses on two areas that have yielded new useful information during the last 20 years: (i) structure-activity relationship (SAR) studies of contact allergy based on the concept of hapten-protein binding and (ii) mechanistic investigations regarding activation of nonsensitizing compounds to contact allergens by air oxidation or skin metabolism. The second area is more thoroughly reviewed since the full picture has previously not been published. Prediction of the sensitizing capacity of a chemical is important to avoid outbreaks of ACD in the population. Much research has been devoted to the development of in vitro and in silico predictive testing methods. Today, no method exists that is sensitive enough to detect weak allergens and that is robust enough to be used for routine screening. To cause sensitization, a chemical must bind to macromolecules (proteins) in the skin. Expert systems containing information about the relationship between the chemical structure and the ability of chemicals to haptenate proteins are available. However, few designed SAR studies based on mechanistic investigations of prohaptens have been published. Many compounds are not allergenic themselves but are activated in the skin (e.g., metabolically) or before skin contact (e.g., via air oxidation) to form skin sensitizers. Thus, more basic research is needed on the chemical reactions involved in the antigen formation and the immunological mechanisms. The clinical importance of air oxidation to activate nonallergenic compounds has been demonstrated. Oxidized fragrance terpenes, in contrast to the pure terpenes, gave positive patch test reactions in consecutive dermatitis patients as frequently as the most common standard allergens. This shows the importance of using compounds to which people are exposed when screening for ACD in dermatology clinics.
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Affiliation(s)
- Ann-Therese Karlberg
- Dermatochemistry and Skin Allergy and Medical Chemistry, Department of Chemistry, Götegorg University, Göteborg, Sweden.
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29
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Respiratory sensitization and allergy: current research approaches and needs. Toxicol Appl Pharmacol 2007; 226:1-13. [PMID: 18023833 DOI: 10.1016/j.taap.2007.10.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 09/07/2007] [Accepted: 10/05/2007] [Indexed: 11/24/2022]
Abstract
There are currently no accepted regulatory models for assessing the potential of a substance to cause respiratory sensitization and allergy. In contrast, a number of models exist for the assessment of contact sensitization and allergic contact dermatitis (ACD). Research indicates that respiratory sensitizers may be identified through contact sensitization assays such as the local lymph node assay, although only a small subset of the compounds that yield positive results in these assays are actually respiratory sensitizers. Due to the increasing health concerns associated with occupational asthma and the impending directives on the regulation of respiratory sensitizers and allergens, an approach which can identify these compounds and distinguish them from contact sensitizers is required. This report discusses some of the important contrasts between respiratory allergy and ACD, and highlights several prominent in vivo, in vitro and in silico approaches that are being applied or could be further developed to identify compounds capable of causing respiratory allergy. Although a number of animal models have been used for researching respiratory sensitization and allergy, protocols and endpoints for these approaches are often inconsistent, costly and difficult to reproduce, thereby limiting meaningful comparisons of data between laboratories and development of a consensus approach. A number of emerging in vitro and in silico models show promise for use in the characterization of contact sensitization potential and should be further explored for their ability to identify and differentiate contact and respiratory sensitizers. Ultimately, the development of a consistent, accurate and cost-effective model will likely incorporate a number of these approaches and will require effective communication, collaboration and consensus among all stakeholders.
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Nanney LB, Caldwell RL, Pollins AC, Cardwell NL, Opalenik SR, Davidson JM. Novel approaches for understanding the mechanisms of wound repair. J Investig Dermatol Symp Proc 2006; 11:132-9. [PMID: 17069021 DOI: 10.1038/sj.jidsymp.5650002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mechanisms that drive wound repair are complex and have challenged wound-healing investigators for many years. In this review, we present four examples of new tools that are being utilized to discover events that drive wound repair and regeneration. Laser capture microdissection facilitates the focused collection of tissue for purposes of genomic or proteomic analysis from specific cell populations within the wound bed. Tissue profiling and protein imaging by matrix-assisted laser desorption ionization mass spectrometry are two proteomic-based tools that permit rapid analysis with spatial orientation and relative abundance of hundreds to thousands of molecules from intact tissues. Another approach uses an in vivo porcine model to harness a strategy of adenoviral-driven receptor overexpression. This biological model closely mimics the human setting and permits transient stimulation along a specific cytokine pathway to tip the balance in favor of accelerated repair. The advent of new approaches that collect cell samples from within their in vivo circumstance while preserving discrete cellular localizations is likely to move the field of wound repair forward.
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Affiliation(s)
- Lillian B Nanney
- Department of Plastic Surgery Research Laboratory, Vanderbilt School of Medicine, Nashville, Tennessee 37232, USA.
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Pickard C, Smith AM, Cooper H, Strickland I, Jackson J, Healy E, Friedmann PS. Investigation of mechanisms underlying the T-cell response to the hapten 2,4-dinitrochlorobenzene. J Invest Dermatol 2006; 127:630-7. [PMID: 17008874 DOI: 10.1038/sj.jid.5700581] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
T-cell mediated contact sensitization by small molecular weight xenobiotics results in significant morbidity and absences from work. To be recognized by T-cells, xenobiotics must act as haptens, becoming protein-bound. At present, the requirement for processing and presentation of xenobiotics, the nature of the T-cell responses to them and the mechanisms that confer individual susceptibility in humans are unclear. We have investigated the T-cell response to the hapten 2,4-dinitrochlorobenzene (DNCB) which can sensitize all immunocompetent people. Fourteen healthy adults were sensitized with DNCB; 11 demonstrated positive T-cell responses to the chemical in vitro. Responding cells were of both CD4+ and CD8+ subsets, of Th1 and Tc1 phenotypes, producing high levels of IFN-gamma and low levels of IL-10. DNCB-specific T-cell clones were raised from 2 subjects, which in the presence of fixed and unfixed autologous Epstein-Barr virus transformed B cells as antigen-presenting-cells (APC), demonstrated that the chemical requires metabolic processing by the APC in order to initiate the T-cell response. Intracellular-reduced glutathione is consumed in detoxication of DNCB, leaving residual non-detoxified DNCB free to bind to proteins. The results suggest that DNCB forms multiple haptens with intracellular and extracellular proteins leading to Th1 and Tc1 responses in individuals exposed to this compound.
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Affiliation(s)
- Chris Pickard
- Dermatopharmacology Unit, Southampton General Hospital, Southampton, UK
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32
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Beltrani VS, Bernstein I, Cohen DE, Fonacier L. Contact dermatitis: a practice parameter. Ann Allergy Asthma Immunol 2006. [DOI: 10.1016/s1081-1206(10)60811-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Divkovic M, Pease CK, Gerberick GF, Basketter DA. Hapten-protein binding: from theory to practical application in the in vitro prediction of skin sensitization. Contact Dermatitis 2005; 53:189-200. [PMID: 16191014 DOI: 10.1111/j.0105-1873.2005.00683.x] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In view of the forthcoming European Union ban on in vivo testing of cosmetic and toiletry ingredients, following the publication of the 7th amendment to the Cosmetics Directive, the search for practical, alternative, non-animal approaches is gathering pace. For the end-point of skin sensitization, the ultimate goal, i.e. the development and validation of alternative in vitro/in silico assays by 2013, may be achieved through a better understanding of the skin sensitization process on the cellular and molecular levels. One of the key molecular events in skin sensitization is protein haptenation, i.e. the chemical modification of self-skin protein(s) thus forming macromolecular immunogens. This concept is widely accepted and in theory can be used to explain the sensitizing capacity of many known skin sensitizers. Thus, the principle of protein or peptide haptenation could be used in in vitro assays to predict the sensitization potential of a new chemical entity. In this review, we consider some of the theoretical aspects of protein haptenation, how mechanisms of protein haptenation can be investigated experimentally and how we can use such knowledge in the development of novel, alternative approaches for predicting skin sensitization potential in the future.
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