title: Differentiation of naive CD4+ T cells into CD4+CD25+FOXP3+ regulatory T cells by continuous antigen stimulation.
abstract: Human CD4+CD25+ regulatory T (T(R)) cells express the transcription factor forkhead box p3 (FOXP3) and have potent immunosuppressive properties. While naturally occurring T(R) cells develop in the thymus, adaptive T(R) cells develop in the periphery from naive CD4+ T cells. Adaptive T(R) cells may express cyclooxygenase type 2 (COX-2) and suppress effector T cells by a PGE(2)-dependent mechanism, which is reversible with COX inhibitors. In this study we have characterized the differentiation of naive CD4+ T cells into adaptive T(R) cells in detail during 7 days of continuous antigen stimulation. After 2 days of stimulation of CD4+CD25- T cells, the cells expressed FOXP3 and COX-2 and displayed potent immunosuppressive properties. The suppressive phenotype was present at all observed time-points from Day 2, although suppression was merely present at Day 7. The adaptive T(R) cells expressed cell surface markers consistent with an activated phenotype and secreted high levels of TGF-beta, IL-10, and PGE(2). However, the suppressive phenotype was found exclusively in cells that proliferated upon activation. These data support the notion that activation of naive CD4+ T cells leads to concomitant acquisition of effector and suppressive properties.
authors.affiliation: The Biotechnology Centre of Oslo, University of Oslo, Gaustadalleen 21, N-0349 Oslo, Norway.
authors.forename: Milada
authors.initials: M
authors.lastname: Mahic
authors.forename: Sheraz
authors.initials: S
authors.lastname: Yaqub
authors.forename: Tone
authors.initials: T
authors.lastname: Bryn
authors.forename: Karen
authors.initials: K
authors.lastname: Henjum
authors.forename: Dag M
authors.initials: DM
authors.lastname: Eide
authors.forename: Knut M
authors.initials: KM
authors.lastname: Torgersen
authors.forename: Einar M
authors.initials: EM
authors.lastname: Aandahl
authors.forename: Kjetil
authors.initials: K
authors.lastname: Taskén
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000494:pharmacology; D001782:Blood Donors; D015704:CD4 Antigens / Q000032:analysis*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000276:immunology*; D002454:Cell Differentiation; D002455:Cell Division; D018920:Coculture Techniques; D004768:Enterotoxins / Q000494:pharmacology; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000032:analysis* / Q000235:genetics; D006801:Humans; D007165:Immunosuppression Therapy; D053645:Interleukin-2 Receptor alpha Subunit / Q000032:analysis*; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D015704:CD4 Antigens; D004768:Enterotoxins; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D053645:Interleukin-2 Receptor alpha Subunit; C031818:enterotoxin B, staphylococcal