title: Ganoderic acid Me induces the apoptosis of competent T cells and increases the proportion of Treg cells through enhancing the expression and activation of indoleamine 2,3-dioxygenase in mouse lewis lung cancer cells.
abstract: The indoleamine 2,3-dioxygenase-(IDO-) mediated microenvironment plays an important role in tumor immune escape. It is known that ganoderic acid Me can enhance IFN-γ expression and IDO is preferentially induced by IFN-γ. However, whether GA-Me can induce IDO expression has not been clarified yet. We established stable clones of IDO-overexpressing 2 LL cells (2LL-EGFP-IDO). After co-culturing with IDO expressing or control vector-transfected 2LL-EGFP cells, T cell apoptosis was determined and the proportion of the regulatory T cells (Tregs) and CD8+ T cell subset was measured. The total cellular protein samples of 2 LL-EGFP-IDO cells were isolated for detecting JAK-STAT1 signalling pathway. Co-culture supernatants were used to detect amino acids and cytokines. IDO transfected 2 LL cells yielded high level of IDO enzymatic activity, resulting in complete depletion of tryptophan from the culture medium. We found that apoptosis occurred in T cells after cocultured with IDO+2LL cells and the proportion of CD4+CD25+ cells and FoxP3+ cells increased while CD8+ cells decreased. The specific inhibitor of IDO, 1-D-MT and GA-Me efficiently enhanced T cell apoptosis, increased Tregs, and reduced CD8+ T cells in vitro. Increased expression of IDO, p-JAK1 and p-STAT1 were confirmed by Western blot analysis. The levels of IFN-γ, IL-10, LDH and kynurenine in co-culture supernatant correspondingly increased, while tryptophan reduced. These results suggest that GA-Me contributing to IDO helps to create a tolerogenic milieu in lung tumors by directly inducing T cell apoptosis, restraining CD8+ T cell activation, and enhancing Treg-mediated immunosuppression.
authors.affiliation: Department of Molecular & Cellular Pharmacology, Biomedical Nanotechnology Center, State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Zujun
authors.initials: Z
authors.lastname: Que
authors.affiliation: Department of Molecular & Cellular Pharmacology, Biomedical Nanotechnology Center, State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Fangyuan
authors.initials: F
authors.lastname: Zou
authors.affiliation: Department of Molecular & Cellular Pharmacology, Biomedical Nanotechnology Center, State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Anle
authors.initials: A
authors.lastname: Zhang
authors.affiliation: Department of Molecular & Cellular Pharmacology, Biomedical Nanotechnology Center, State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Yuanhong
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 200032, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Bi
authors.affiliation: State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dong-Chuan Road, Shanghai 200240, PR China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China.
authors.forename: Jianjiang
authors.initials: J
authors.lastname: Zhong
authors.affiliation: Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 200032, PR China.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Tian
authors.affiliation: Department of Molecular & Cellular Pharmacology, Biomedical Nanotechnology Center, State Key Laboratory of Bioreactor Engineering & Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China. Electronic address: liujian@ecust.edu.cn.
authors.forename: Jianwen
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D018827:Carcinoma, Lewis Lung / Q000188:drug therapy* / Q000276:immunology; D002999:Clone Cells; D018920:Coculture Techniques; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000235:genetics / Q000378:metabolism*; D007371:Interferon-gamma / Q000378:metabolism; D007375:Interleukin-1 / Q000378:metabolism; D053612:Janus Kinases / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008517:Phytotherapy / Q000379:methods*; D020940:Reishi / Q000276:immunology; D050794:STAT1 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects* / Q000276:immunology; D014315:Triterpenes / Q000494:pharmacology*; D019139:Tumor Escape
chemical_list: D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D007375:Interleukin-1; D050794:STAT1 Transcription Factor; D014315:Triterpenes; C534033:ganoderic acid Me; D007371:Interferon-gamma; D053612:Janus Kinases
keywords: Co-culture; GA-Me; IDO1; Mouse lewis lung cancer cells; Treg