PMID- 34311055 OWN - NLM STAT- MEDLINE DCOM- 20220107 LR - 20220107 IS - 1096-0295 (Electronic) IS - 0273-2300 (Linking) VI - 125 DP - 2021 Oct TI - Development of quantitative model of a local lymph node assay for evaluating skin sensitization potency applying machine learning CatBoost. PG - 105019 LID - S0273-2300(21)00160-4 [pii] LID - 10.1016/j.yrtph.2021.105019 [doi] AB - The estimated concentrations for a stimulation index of 3 (EC3) in murine local lymph node assay (LLNA) is an important quantitative value for determining the strength of skin sensitization to chemicals, including cosmetic ingredients. However, animal testing bans on cosmetics in Europe necessitate the development of alternative testing methods to LLNA. A machine learning-based prediction method can predict complex toxicity risks from multiple variables. Therefore, we developed an LLNA EC3 regression model using CatBoost, a new gradient boosting decision tree, based on the reliable Cosmetics Europe database which included data for 119 substances. We found that a model using in chemico/in vitro tests, physical properties, and chemical information associated with key events of skin sensitization adverse outcome pathway as variables showed the best performance with a coefficient of determination (R(2)) of 0.75. In addition, this model can indicate the variable importance as the interpretation of the model, and the most important variable was associated with the human cell line activation test that evaluate dendritic cell activation. The good performance and interpretability of our LLNA EC3 predictable regression model suggests that it could serve as a useful approach for quantitative assessment of skin sensitization. CI - Copyright (c) 2021 The Authors. Published by Elsevier Inc. All rights reserved. FAU - Ambe, Kaori AU - Ambe K AD - Department of Regulatory Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan. Electronic address: ambek@phar.nagoya-cu.ac.jp. FAU - Suzuki, Masaharu AU - Suzuki M AD - Department of Regulatory Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan. Electronic address: c202712@ed.nagoya-cu.ac.jp. FAU - Ashikaga, Takao AU - Ashikaga T AD - Division of Risk Assessment, National Institute of Health Sciences, Kawasaki, Japan. Electronic address: takao.ashikaga@nihs.go.jp. FAU - Tohkin, Masahiro AU - Tohkin M AD - Department of Regulatory Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan. Electronic address: tohkin@phar.nagoya-cu.ac.jp. LA - eng PT - Journal Article DEP - 20210724 PL - Netherlands TA - Regul Toxicol Pharmacol JT - Regulatory toxicology and pharmacology : RTP JID - 8214983 SB - IM MH - Animal Testing Alternatives MH - Animals MH - Cell Line MH - Databases, Factual MH - Dendritic Cells/drug effects MH - Dermatitis, Allergic Contact/*diagnosis MH - Europe MH - Humans MH - Keratinocytes/drug effects MH - *Local Lymph Node Assay MH - *Machine Learning MH - Mice MH - T-Lymphocytes/drug effects MH - United Nations/standards OTO - NOTNLM OT - Adverse outcome pathway OT - CatBoost OT - Integrated approaches to testing and assessment OT - Machine learning OT - Murine local lymph node assay OT - Quantitative model OT - Skin sensitization EDAT- 2021/07/27 06:00 MHDA- 2022/01/08 06:00 CRDT- 2021/07/26 20:12 PHST- 2020/11/15 00:00 [received] PHST- 2021/06/13 00:00 [revised] PHST- 2021/07/21 00:00 [accepted] PHST- 2021/07/27 06:00 [pubmed] PHST- 2022/01/08 06:00 [medline] PHST- 2021/07/26 20:12 [entrez] AID - S0273-2300(21)00160-4 [pii] AID - 10.1016/j.yrtph.2021.105019 [doi] PST - ppublish SO - Regul Toxicol Pharmacol. 2021 Oct;125:105019. doi: 10.1016/j.yrtph.2021.105019. Epub 2021 Jul 24.