API

Event: 312

Key Event Title

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N/A, Allergic contact dermatitis on challenge

Short name

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N/A, Allergic contact dermatitis on challenge

Key Event Component

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Process Object Action

Key Event Overview


AOPs Including This Key Event

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Stressors

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Level of Biological Organization

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Biological Organization
Individual



Taxonomic Applicability

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Term Scientific Term Evidence Link
human Homo sapiens Strong NCBI
mouse Mus musculus Strong NCBI
guinea pig Cavia porcellus Strong NCBI

Life Stages

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Sex Applicability

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How This Key Event Works

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In vivo studies, including ones with human subjects, have been critical in the evolution of the science of skin sensitisation. Human sensitisation testing is conducted with the human repeat insult patch test (HRIPT), as described by McNamee et al.[1]. The experimental endpoint of this type of study can be considered the adverse outcome described as allergic contact dermatitis. Dermal sensitizers are assumed to elicit an adverse effect only after a threshold dose is reached. Above this threshold, the severity of the adverse effect is assumed to increase proportionally to the dose, so the total dose per area of skin (e.g. μg/cm2) is the critical exposure determinant. In this regard, animal data is consistent with human clinical data ([2]). These observations are consistent with the immunological mechanism presented with this AOP, where it is assumed that for an adverse outcome to commence, a certain number of dendritic cells is required to be activated and to migrate to the nearest lymph node in order to instigate the further cascade of biological events (see [2]).

Today the generation of sensitisation data in animal models remains the basis of assessing the sensitisation potential of chemicals. Adler et al.[3] have reviewed animal test methods for skin sensitisation. Briefly, among these in vivo assays are the guinea-pig occluded patch test ([4];[5];[5]), the Magnusson-Kligman guinea-pig maximization test [6]; [5];[7]), and the murine LLNA ([8];[9]; [10],[11],[12]). Positive results in the occluded patch test or the guinea-pig maximization test can be considered the adverse outcome described as contact hypersensitivity.

The similarities and differences between results, with the guinea-pig test, the LLNA and where available human evidence, is important in the IPCS MOA Framework[13] and addressed through the Bradford Hill criteria. While it will have implication in human risk assessment and classification and labelling under existing standards, it has less of an impact on the acceptance of an AOP and its use in forming chemical categories and integrated assessment and testing approaches.


How It Is Measured or Detected

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In vivo studies, including ones with human subjects, have been critical in the evolution of the science of skin sensitisation. Human sensitisation testing is conducted with the human repeat insult patch test (HRIPT), as described by McNamee et al[1].


Evidence Supporting Taxonomic Applicability

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In vivo studies remain the basis of assessing the sensitisation potential of chemicals (see[3]) As previously noted, human sensitisation testing is conducted with the HRIPT ([1]). Other in vivo methods include the guinea-pig occluded patch test[5], the Magnusson- Kligman guinea-pig maximization test ([5]), and the mouse LLNA ([10];[11];[12]). While quantitative models have been developed with guinea-pig data, the LLNA assay was designed to allow for a direct quantitative assessment of skin sensitisation potency. Briefly, the relative potency of a skin-sensitizing chemical is measured by derivation of an ECx value, which is the concentration of a test chemical necessary to produce a X-fold increase in lymph node cell proliferation compared with concurrent vehicle controls (i.e. a threshold positive response) ([14]). Since the LLNA does not include the challenge phase of sensitisation, it may be considered an incomplete in vivo sensitisation assay. Using LLNA data, sensitizers can be grouped into potency groups (e.g. extreme, strong, moderate, weak, and non-sensitizers). However, as noted by Basketter et al. ([15]), the LLNA is not without limitations, including variability between EC3 values or any other value (i.e. ECx) within isoreactive mechanistic classes. There are increased efforts to look at in vivo skin sensitisation potential or lack of potential as concordance between LLNA and guinea-pig data, and human evidence.


References

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  1. 1.0 1.1 1.2 McNamee PM, Api AM, Basketter DA, Gerberick GF, Gilpin DA, Hall BM, Jowsey I, Robinson MK. 2008. A review of critical factors in the conduct and interpretation of the human repeat insult patch test. Reg. Toxicol. Pharmacol. 52: 24-34.
  2. 2.0 2.1 Api AM, Basketter DA, Cadby PA, Cano MF, Ellis G, Gerberick GF, Griem P, McNamee PM, Ryan CA, Safford B. 2008. Dermal sensitisation quantitative risk assessment (QRA) for fragrance ingredients. Reg. Toxicol. Pharmcol. 52: 3-23.
  3. 3.0 3.1 3.2 3.3 Adler S, BasketterD, Creton S, Pelkonen O, van Benthem J, Zuang V, Ejner-Andersen K, Angers- Loustau A, Aptula A, Bal-Price A, Benfenati E, Bernauer U, Bessems J, Bois FY, Boobis A, Brandon E, Bremer S, Broschard T, Casati S Coecke S Corvi R, Cronin M, Daston G, Dekant W, Felter S, Grignard E, Gundert-Remy U, Heinonen T, Kimber I, Kleinjans J, Komulainen H, Kreiling R, Kreysa J, Batista Leite S, Loizou G, Maxwell G, Mazzatorta P, Munn S, Pfuhler S, Phrakonkham P, Piersma A, Poth A, Prieto P, Repetto G, Rogiers V, Schoeters G, Schwarz M, Serafimova R, Tahti H, Testai E, van Delft J, van Loveren H, Vinken M, Worth A, Zaldivar JM. 2011. Alternative (non-animal) methods for cosmetics testing: current status and future prospects-2010. Arch. Toxicol. 85: 367-485.
  4. Buehler EV. 1965. Delayed hypersensitivity in the guinea pig. Arch. Dermatol. 91: 171-177.
  5. 5.0 5.1 5.2 5.3 5.4 Organization for Economic Co-operation and Development (OECD) 1992. Test No. 406: Skin Sensitisation, OECD Guidelines for the Testing of Chemicals, Section 4: Health Effects, OECD Publishing. doi: 10.1787/9789264070660-en
  6. Magnusson B and Kligman AM. 1970. Allergic Contact Dermatitis in the Guinea Pig. Identification of Contact Allergens. Charles C Thomas, ; Springfield, IL USA.
  7. Maurer T, Arthur A, Bentley P. 1994. Guinea-pig contact sensitisation assays. Toxicology 93: 47- 54.
  8. 8.0 8.1 Basketter DA, Gerberick GF, Kimber I, Loveless SE. 1996. The local lymph node assay: a viable alternative to currently accepted skin sensitisation tests. Food Chem. Toxicol. 34: 985-997.
  9. Kimber I, Basketter DA, Gerberick GF, Dearman RJ. 2002a. Allergic contact dermatitis. Int.Immunopharmacol. 2: 201-211.
  10. 10.0 10.1 OECD 2010a. Test No. 429: Skin Sensitisation: Local Lymph Node Assay, OECD Guidelines for the Testing of Chemicals, Section 4: Health Effects, OECD Publishing. doi: 10.1787/9789264071100- en
  11. 11.0 11.1 OECD 2010b. Test No. 442A: Skin Sensitisation: Local Lymph Node Assay: DA, OECD Guidelines for the Testing of Chemicals, Section 4: Health Effects, OECD Publishing. doi: 10.1787/9789264090972- en
  12. 12.0 12.1 OECD 2010c. Test No. 442B: Skin Sensitisation: Local Lymph Node Assay: BrdU-ELISA, OECD Guidelines for the Testing of Chemicals, Section 4: Health Effects, OECD Publishing. doi: 10.1787/9789264090996-en
  13. Boobis AR, Doe JE, Heinrich-Hirsch B, Meek ME, Munn S, Ruchirawat M, Schlatter J, Seed J, Vickers C. 2008. IPCS framework for analyzing the relevance of the non-cancer mode of action for humans. Crit. Rev. Toxicol. 38: 87-96.
  14. Basketter DA, Lea LJ, Cooper KJ, Dickens A, Stocks J, Pate I. 1999. Thresholds for classification as a skin sensitiser in the local lymph node assay: a statistical evaluation. Food Chem. Toxicol. 37:1167-1174.
  15. Basketter DA, McFadden JF, Gerberick F, Cochshott A, Kimber I. 2009. Nothing is perfect, not even the local lymph node assay: a commentary and the implications for REACH. Contact Dermatitis 60: 65-69.
  16. Aeby P, Ashikaga T, Bessou-Touya S, Schapky A, Geberick F, Kern P, Marrec-Fairley M, Maxwell G, Ovigne J-M, Sakaguchi H, Reisinger K, Tailhardat M, Martinozzi-Teisser S, Winkler P 2010. Identifying and characterizing chemical skin sensitizers without animal testing; Colipa’s research and methods development program. Toxicol. In Vitro 24: 1465-1473.
  17. Basketter DA and Kimber I. 2010. Contact hypersensitivity. In: McQueen, CA (ed) Comparative Toxicology Vol. 5, 2nd Ed. Elsevier, Kidlington, UK, pp. 397-411.
  18. Kimber I, Dearman RJ, Basketter DA, Ryan CA, Gerberick GF. 2002b. The local lymph node assay: past, present and future. Contact Dermatitis 47: 315-328.
  19. Basketter DA, Lea LJ, Cooper KJ, Dickens A, Stocks J, Pate I. 1999. Thresholds for classification as a skin sensitiser in the local lymph node assay: a statistical evaluation. Food Chem. Toxicol. 37:1167-1174.
  20. Basketter DA, McFadden JF, Gerberick F, Cochshott A, Kimber I. 2009. Nothing is perfect, not even the local lymph node assay: a commentary and the implications for REACH. Contact Dermatitis 60: 65-69.
  21. Ball N, Cagen S, Carrillo JC, Certa H, Eigler D, Emter R, Faulhammer F, Garcia C, Graham C, Haux C, Kolle SN, Kreiling R, Natsch A, Mehling A. 2011. Evaluating the sensitisation potential of surfactants: Integrating data from the local lymph node assay, guinea pig maximization test, and in vitro methods in a weight-of-evidence approach, Reg. Toxicol. Pharmacol., doi:10.1016/j.yrtph.2011.05.007