PMID- 20491607
OWN - NLM
STAT- MEDLINE
DCOM- 20110204
LR  - 20161125
IS  - 1556-9535 (Electronic)
IS  - 1556-9527 (Linking)
VI  - 29
IP  - 3
DP  - 2010 Sep
TI  - A new in vitro method for identifying chemical sensitizers combining peptide 
      binding with ARE/EpRE-mediated gene expression in human skin cells.
PG  - 171-92
LID - 10.3109/15569527.2010.483869 [doi]
AB  - Allergic contact dermatitis (ACD) is a significant safety concern for developers 
      of cosmetic, personal care, chemical, pharmaceutical, and medical device 
      products. The guinea pig maximization test (GMPT) and the murine local lymph node 
      assay (LLNA) are accepted methods for determining chemical sensitization. Recent 
      legislative initiatives in Europe require the development of new in vitro 
      alternatives to animal tests for chemical sensitization. The aim of this project 
      was to develop an in vitro screening method that uses a human skin cell line 
      (HaCaT), chemical reactivity, and gene expression profiling to identify positive 
      and negative responses, to place chemicals into potency categories of 
      extreme/strong (ES), moderate (M), weak (W), and nonsensitizers (N), and to 
      provide an estimate of corresponding LLNA values. The method and processing 
      algorithm were developed from a training set of 39 chemicals possessing a wide 
      range of sensitization potencies. Three cationic metals, chromium (Cr), nickel 
      (Ni), and silver (Ag), were also evaluated in this model. Chemical reactivity was 
      determined by measuring glutathione (GSH) depletion in a cell free matrix. Three 
      signaling pathways (Keap1/Nrf 2/ARE/EpRE, ARNT/AhR/XRE, and Nrf1/MTF/MRE) that 
      are known to be activated by sensitizing agents were monitored by measuring the 
      relative abundance of 11 genes whose expression is controlled by one of these 3 
      pathways. Final exposure concentrations were based on toxicity and solubility. A 
      range-finding experiment was conducted with each compound to determine 
      cytotoxicity and solubility. Six exposure concentrations (0.1 to 2,500 microM) 
      and an exposure time of 24 hours were used in the final experiments. Glutathione 
      depletion alone did not provide the accuracy necessary to differentiate potency 
      categories. However, chemical reactivity combined with gene expression profiles 
      significantly improved the in vitro predictions. A predicted toxicity index (PTI) 
      was determined for each test chemical. A comparison of LLNA values with PTI 
      values revealed an inverse relationship. The large variation in LLNA data for 
      compounds in the same potency category makes direct extrapolation from PTI to 
      LLNA difficult. To challenge the system, 58 additional compounds were submitted 
      in a blinded manner. Compounds placed into ES and M categories were considered 
      positive, whereas compounds classified as W or N were considered negative. 
      Accuracy was approximately 84%, with a sensitivity of 81% and a specificity of 
      92%. The model correctly identified 2 of 3 cationic metals as positive. In 
      conclusion, the method described here demonstrates a valuable in vitro method for 
      identifying chemicals and metals that induce skin sensitization.
FAU - McKim, James M Jr
AU  - McKim JM Jr
AD  - CeeTox Inc., Kalamazoo, Michigan 49008, USA. jmckim@ceetox.com
FAU - Keller, Don J 3rd
AU  - Keller DJ 3rd
FAU - Gorski, Joel R
AU  - Gorski JR
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Cutan Ocul Toxicol
JT  - Cutaneous and ocular toxicology
JID - 101266892
RN  - 0 (HIF1A protein, human)
RN  - 0 (Haptens)
RN  - 0 (Hypoxia-Inducible Factor 1, alpha Subunit)
RN  - 0 (Intracellular Signaling Peptides and Proteins)
RN  - 0 (KEAP1 protein, human)
RN  - 0 (Kelch-Like ECH-Associated Protein 1)
RN  - 0 (MAFF protein, human)
RN  - 0 (MafF Transcription Factor)
RN  - 0 (Nuclear Proteins)
RN  - EC 1.14.14.1 (Cytochrome P-450 CYP1A1)
RN  - GAN16C9B8O (Glutathione)
SB  - IM
MH  - Animals
MH  - Cell Line
MH  - Cytochrome P-450 CYP1A1/metabolism
MH  - Dermatitis, Allergic Contact/*etiology
MH  - Gene Expression/*drug effects
MH  - Glutathione/chemistry
MH  - Haptens/toxicity
MH  - Humans
MH  - Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
MH  - Intracellular Signaling Peptides and Proteins/metabolism
MH  - Kelch-Like ECH-Associated Protein 1
MH  - Keratinocytes/*drug effects/metabolism
MH  - Local Lymph Node Assay
MH  - MafF Transcription Factor/metabolism
MH  - Nuclear Proteins/metabolism
MH  - Response Elements
MH  - Signal Transduction/*drug effects
MH  - Toxicity Tests/*methods
EDAT- 2010/05/25 06:00
MHDA- 2011/02/05 06:00
CRDT- 2010/05/25 06:00
PHST- 2010/05/25 06:00 [entrez]
PHST- 2010/05/25 06:00 [pubmed]
PHST- 2011/02/05 06:00 [medline]
AID - 10.3109/15569527.2010.483869 [doi]
PST - ppublish
SO  - Cutan Ocul Toxicol. 2010 Sep;29(3):171-92. doi: 10.3109/15569527.2010.483869.