PMID- 28826779 OWN - NLM STAT- MEDLINE DCOM- 20171017 LR - 20201209 IS - 1879-3169 (Electronic) IS - 0378-4274 (Linking) VI - 280 DP - 2017 Oct 5 TI - Gene expression profiles in auricle skin as a possible additional endpoint for determination of sensitizers: A multi-endpoint evaluation of the local lymph node assay. PG - 133-141 LID - S0378-4274(17)31245-6 [pii] LID - 10.1016/j.toxlet.2017.08.009 [doi] AB - The murine local lymph node assay (LLNA) is widely used to test chemicals to induce skin sensitization. Exposure of mouse auricle skin to a sensitizer results in proliferation of local lymph node T cells, which has been measured by in vivo incorporation of H(3)-methyl thymidine or 5-bromo-2'-deoxyuridine (BrdU). The stimulation index (SI), the ratio of the mean proliferation in each treated group to that in the concurrent vehicle control group, is frequently used as a regulatory-authorized endpoint for LLNA. However, some non-sensitizing irritants, such as sodium dodecyl sulfate (SDS) or methyl salicylate (MS), have been reported as false-positives by this endpoint. In search of a potential endpoint to enhance the specificity of existing endpoints, we evaluated 3 contact sensitizers; (hexyl cinnamic aldehyde [HCA], oxazolone [OXA], and 2,4-dinitrochlorobenzene [DNCB]), 1 respiratory sensitizer (toluene 2,4-diisocyanate [TDI]), and 2 non-sensitizing irritants (MS and SDS) by several endpoints in LLNA. Each test substance was applied to both ears of female CBA/Ca mice daily for 3 consecutive days. The ears and auricle lymph node cells were analyzed on day 5 for endpoints including the SI value, lymph node cell count, cytokine release from lymph node cells, and histopathological changes and gene expression profiles in auricle skin. The SI values indicated that all the test substances induced significant proliferation of lymph node cells. The lymph node cell counts showed no significant changes by the non-sensitizers assessed. The inflammatory findings of histopathology were similar among the auricle skins treated by sensitizers and irritants. Gene expression profiles of cytokines IFN-gamma, IL-4, and IL-17 in auricle skin were similar to the cytokine release profiles in draining lymph node cells. In addition, the gene expression of the chemokine CXCL1 and/or CXCL2 showed that it has the potential to discriminate sensitizers and non-sensitizing irritants. Our results suggest that multi-endpoint analysis in the LLNA leads to a better determination of the sensitizing potential of test substances. We also show that the gene expression of CXCL1 and/or CXCL2, which is involved in elicitation of contact hypersensitivity (CHS), can be a possible additional endpoint for discrimination of sensitizing compounds in LLNA. CI - Copyright (c) 2017 Elsevier B.V. All rights reserved. FAU - Tsuchiyama, Hiromi AU - Tsuchiyama H AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Maeda, Akihisa AU - Maeda A AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Nakajima, Mayumi AU - Nakajima M AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Kitsukawa, Mika AU - Kitsukawa M AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Takahashi, Kei AU - Takahashi K AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Miyoshi, Tomoya AU - Miyoshi T AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Mutsuga, Mayu AU - Mutsuga M AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Asaoka, Yoshiji AU - Asaoka Y AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. FAU - Miyamoto, Yohei AU - Miyamoto Y AD - Pharmaceutical Clinical Research Development, Toray Industries Inc., 1-1, Nihonbashi-muromachi 2-chome, Chuo-ku, Tokyo, 103-8666, Japan. FAU - Oshida, Keiyu AU - Oshida K AD - Pharmaceutical Research Laboratories, Toray Industries Inc., 10-1, Tebiro 6-chome, Kamakura, Kanagawa, 248-8555, Japan. Electronic address: Keiyu_Oshida@nts.toray.co.jp. LA - eng PT - Journal Article DEP - 20170818 PL - Netherlands TA - Toxicol Lett JT - Toxicology letters JID - 7709027 RN - 0 (Cytokines) RN - 0 (Dinitrochlorobenzene) RN - 0 (Salicylates) RN - 15646-46-5 (Oxazolone) RN - 17X7AFZ1GH (Toluene 2,4-Diisocyanate) RN - 368GB5141J (Sodium Dodecyl Sulfate) RN - 78243HXH5O (2,6-diisocyanatotoluene) RN - LAV5U5022Y (methyl salicylate) SB - IM MH - Animals MH - Cytokines/genetics/metabolism MH - Dinitrochlorobenzene/toxicity MH - Ear Auricle/*metabolism MH - Female MH - Gene Expression Regulation/drug effects MH - *Local Lymph Node Assay MH - Mice MH - Mice, Inbred CBA MH - Oxazolone/toxicity MH - Salicylates/toxicity MH - Skin/*metabolism MH - Sodium Dodecyl Sulfate/toxicity MH - Toluene 2,4-Diisocyanate/toxicity MH - Transcriptome/*drug effects OTO - NOTNLM OT - False-positives OT - Gene expression OT - Local lymph node assay OT - Skin irritation OT - Skin sensitization EDAT- 2017/08/23 06:00 MHDA- 2017/10/19 06:00 CRDT- 2017/08/23 06:00 PHST- 2017/03/30 00:00 [received] PHST- 2017/06/30 00:00 [revised] PHST- 2017/08/09 00:00 [accepted] PHST- 2017/08/23 06:00 [pubmed] PHST- 2017/10/19 06:00 [medline] PHST- 2017/08/23 06:00 [entrez] AID - S0378-4274(17)31245-6 [pii] AID - 10.1016/j.toxlet.2017.08.009 [doi] PST - ppublish SO - Toxicol Lett. 2017 Oct 5;280:133-141. doi: 10.1016/j.toxlet.2017.08.009. Epub 2017 Aug 18.