Evaluation of changes of cell-surface thiols as a new biomarker for in vitro sensitization test.
In order to find a novel biomarker for a simple assay to predict skin sensitization, we evaluated cell-surface thiols as a biomarker reflecting intracellular signaling in THP-1 cells (human monocytic cell line). First, we found that a decrease of cell-surface thiols on hapten-treated THP-1 cells was induced in parallel with phosphorylation of p38 MAPK. Next, we confirmed that 2-mercaptoethanol in the culture medium and the differentiation state of THP-1 cells did not affect the changes of cell-surface thiols by hapten. Changes of cell-surface thiols on THP-1 cells were detected after 2h treatment with most allergens (e.g., DNCB, NiSO(4)), as well as some non-allergens (e.g., Tween80, benzalkonium chloride), though other non-allergens (e.g., SDS, glycerol) had no effect. When either a significant decrease or increase of cell-surface thiols (more than 15% in each case) was used as a criterion, the results using 36 allergens and 16 non-allergens were in good accordance with those of in vivo assays. Finally, we confirmed that ATP, which is released as a consequence of cytotoxicity, did not affect the changes of cell-surface thiols. Our results suggest that changes of cell-surface thiols may be useful for an in vitro sensitization assay, which we designate as the SH test.
Suzuki
Mie
M
Quality Assessment Center, Shiseido Co., Ltd., 2-12-1 Fukuura, Kanazawa-ku, Yokohama-shi, Kanagawa 236-8643, Japan.
Hirota
Morihiko
M
Hagino
Shigenobu
S
Itagaki
Hiroshi
H
Aiba
Setsuya
S
D000255:Adenosine Triphosphate / Q000494:pharmacology; D015415:Biomarkers; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D008623:Mercaptoethanol / Q000494:pharmacology; D010766:Phosphorylation; D012867:Skin / Q000187:drug effects*; D013438:Sulfhydryl Compounds / Q000032:analysis*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D015415:Biomarkers; D013438:Sulfhydryl Compounds; D008623:Mercaptoethanol; D000255:Adenosine Triphosphate; D048051:p38 Mitogen-Activated Protein Kinases