title: Global expression profiling of peripheral Qa-1-restricted CD8αα+TCRαβ+ regulatory T cells reveals innate-like features: implications for immune-regulatory repertoire.
abstract: Among peripheral regulatory T cells, CD8(+) T cells also play an important role in the maintenance of immune homeostasis. A subset of CD8(+) Treg that express αβ T cell receptor (TCR) and CD8αα homodimers can recognize TCR-derived peptides in the context of the class Ib MHC molecule Qa-1. To gain a better understanding of the nature and phenotype of CD8αα(+)TCRαβ+ Treg, a global gene expression profiling using microarray, real-time quantitative polymerase chain reaction, and flow-cytometric analysis was performed using functional Treg clones and lines. The study findings show that CD8(+) Treg shared gene profile expressed by innate-like lymphocytes, including murine intraepithelial lymphocytes and thymic CD8αα(+)TCRαβ+ T-cell populations. In addition, this subset displays differential expression of several key regulatory molecules, including CD200. CD8αα(+) Treg expressed higher levels of a number of natural killer cell-related receptors and molecules belonging to the TNF superfamily. Collectively, peripheral class Ib-reactive CD8αα(+)TCRαβ+ T cells represent a unique regulatory population different from class Ia major histocompatibility complex-restricted conventional T cells. These studies have important implications for the regulatory mechanisms mediated by the CD8(+) Treg population in general.
authors: Laboratory of Autoimmunity, Torrey Pines Institute for Molecular Studies, San Diego, California, USA.
authors: Shaohsuan S
authors: SS
authors: Fanchiang
authors: Radu
authors: R
authors: Cojocaru
authors: Mohammad
authors: M
authors: Othman
authors: Ritu
authors: R
authors: Khanna
authors: Matthew J
authors: MJ
authors: Brooks
authors: Trevor
authors: T
authors: Smith
authors: Xiaolei
authors: X
authors: Tang
authors: Igor
authors: I
authors: Maricic
authors: Anand
authors: A
authors: Swaroop
authors: Vipin
authors: V
authors: Kumar
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D016827:CD8 Antigens / Q000378:metabolism; D002460:Cell Line; D002999:Clone Cells; D020869:Gene Expression Profiling; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D007113:Immunity, Innate; D056747:Immunomodulation; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D020411:Oligonucleotide Array Sequence Analysis; D061166:Peripheral Tolerance; D011485:Protein Binding; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
chemical_list: D015703:Antigens, CD; D016827:CD8 Antigens; C409469:CD8 antigen, alpha chain; D015395:Histocompatibility Antigens Class I; C032907:Q surface antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta; C042739:antigens, CD200