title: A pivotal role of vitamin B9 in the maintenance of regulatory T cells in vitro and in vivo.
abstract: Dietary factors regulate immunological function, but the underlying mechanisms remain elusive. Here we show that vitamin B9 is a survival factor for regulatory T (Treg) cells expressing high levels of vitamin B9 receptor (folate receptor 4). In vitamin B9-reduced condition in vitro, Treg cells could be differentiated from naïve T cells but failed to survive. The impaired survival of Treg cells was associated with decreased expression of anti-apoptotic Bcl2 and independent of IL-2. In vivo depletion of dietary vitamin B9 resulted in the reduction of Treg cells in the small intestine, a site for the absorption of dietary vitamin B9. These findings provide a new link between diet and the immune system, which could maintain the immunological homeostasis in the intestine.
authors.affiliation: Division of Mucosal Immunology, Department of Microbiology and Immunology, Institute of Medical Science, The University of Tokyo, Tokyo, Japan. kunisawa@ims.u-tokyo.ac.jp
authors.forename: Jun
authors.initials: J
authors.lastname: Kunisawa
authors.forename: Eri
authors.initials: E
authors.lastname: Hashimoto
authors.forename: Izumi
authors.initials: I
authors.lastname: Ishikawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kiyono
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000494:pharmacology*; D051858:Forkhead Transcription Factors / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007421:Intestine, Small / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D015398:Signal Transduction / Q000187:drug effects; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*
chemical_list: D002352:Carrier Proteins; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D007376:Interleukin-2; D005492:Folic Acid