2, 3, 7, 8-Tetrachloodibenzo-p-dioxin affects the differentiation of CD4 helper T cell. (1st September 2019)

• Record Type: Journal Article
• Authors: Pang, Chengfang; Zhu, Conghui; Zhang, Yuanyuan; Ge, Ying; Li, Shujuan; Huo, Shouliang; Xu, Tuan; Stauber, Roland H.; Zhao, Bin
• Is Part Of: Toxicology letters. Volume 311(2019)
• Page Start: 49
• Page End: 57
• Publication Date: 2019-09-01
• Subjects: Dioxin -- TCDD -- Helper T cell -- Cell differentiation -- Immune suppression -- AhR; Toxicology -- Periodicals; 363.179
• DOI: 10.1016/j.toxlet.2019.04.015
• Languages: English
• ISSNs: 0378-4274

Abstract

Graphical abstract: Highlights: TCDD had a dose-dependent effect to differentiation of CD4 helper T cell. The absence of Treg shows different effect to immune regulation and toxicity. Microenvironment might influence the TCDD's effects to CD4 helper T cell. Abstract: 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener of dioxins, is a persistent and ubiquitous environmental contaminant. Although the immunotoxic effects of TCDD have been reported, the mechanisms underlying these effects are still unclear. In this study, we have determined the toxic effects of TCDD on thymocytes and splenic T cells with in vitro cell culture systems. Magnetically isolated mouse splenic Th cells, Treg cells and the mixed spleen lymphocytes (SLC) were cultured and treated with TCDD and the differentiation of CD4 Th cells was determined by flow cytometery. Our results showed that different concentrations of TCDD caused immunotoxic effects through different toxicological mechanisms in both the purified mouse splenic Th cells and the mixed SLC. The low dose exposure to TCDD triggered regulatory effects in the immune system, while the high dose TCDD exposure resulted in severe immune toxicity. Notably, a decline of Treg subset was observed, suggesting an imbalanced immune regulation by TCDD treatment, as well as a possible decrease of TCDD's indirect effects on bystander immune cells. Our CD4 Th subset co-culture experiments showed that TCDD-induced pathobiology depended on immune cell balance, suggesting that cytokine-induced microenvironments further modulated toxic effects associated with TCDD exposure.