title: Regulatory T-Cell (Treg) hybridoma as a novel tool to study Foxp3 regulation and Treg fate.
abstract: The CD25(+)Foxp3(+) regulatory T-cells (Treg) that had lost CD25 and Foxp3 in vivo (ex-Treg) exist but are difficult to study. We generated antigen (Ag)-specific Treg hybridomas from iTreg clones (iTreg-hyb) using iTreg of DO11.10.Foxp3-GFP mice and presented evidence that they behave like ex-Treg. The iTreg-hyb displayed little CD25 and Foxp3-GFP but strong expression could be induced with OVA(323-339) in the presence of Ag-presenting cells, rIL-2 and rTGF-β1. They displayed all of the iTreg-associated markers examined except CTLA-4, the latter was also absent in the ex-Treg. They lacked the Helios transcription factor, suggesting they were derived from iTreg. Similar to ex-Treg, the iTreg-hyb produced high level of IL-2 and Foxp3 under specific activation conditions. Two unusual properties were observed. First, the ability to induce Foxp3-GFP upon activation is progressively lost in culture over a period of 2-4 weeks. Second, Rag2(-/-) spleen cells alone selectively induced Foxp3-GFP expression albeit 30 times less efficient than Ag-specific activation. We identified cell-free supernatant, IL-6, IL-9, and IL-27 as Foxp3-inducing factors. Our study has significant implications to the stability, plasticity and fate of Treg. The usefulness and limitation of iTreg-hyb as a novel tool to study Foxp3 regulation and the fate of specific Treg subsets are discussed.
authors.affiliation: Center for Immunity, Inflammation and Regenerative Medicine, Department of Medicine, University of Virginia, Charlottesville, VA 22908-0412, USA.
authors.forename: Rahul
authors.initials: R
authors.lastname: Sharma
authors.forename: Sun-Sang J
authors.initials: SS
authors.lastname: Sung
authors.forename: Chiao-Ying A
authors.initials: CY
authors.lastname: Ju
authors.forename: Umesh S
authors.initials: US
authors.lastname: Deshmukh
authors.forename: Shu Man
authors.initials: SM
authors.lastname: Fu
authors.forename: Shyr-Te
authors.initials: ST
authors.lastname: Ju
mesh_terms: D000818:Animals; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000276:immunology; D006825:Hybridomas; D007158:Immunologic Techniques / Q000639:trends; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D008213:Lymphocyte Activation / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D010047:Ovalbumin / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D037182:T-Cell Antigen Receptor Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D019076:Transgenes / Q000235:genetics
chemical_list: D016207:Cytokines; D004268:DNA-Binding Proteins; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D053645:Interleukin-2 Receptor alpha Subunit; C111390:OVA 323-339; D010446:Peptide Fragments; C499308:Rag2 protein, mouse; D010047:Ovalbumin