title: Insufficient secretion of IL-10 by Tregs compromised its control on over-activated CD4+ T effector cells in newly diagnosed adult immune thrombocytopenia patients.
abstract: Primary immune thrombocytopenia (ITP) is an autoimmune heterogeneous disorder. Excessive activated CD4(+) T effector cells (Teffs) and compromised regulatory T cells (Tregs) were reported in ITP patients, yet little is known about the mechanisms. Interleukin-10 (IL-10) is an important regulatory cytokine of Tregs in inflammatory condition. It has been recently highlighted that IL-10-producing Tregs contribute to the effective controls of several autoimmune diseases. Hence this study was aimed to examine the role of IL-10 produced by Tregs in newly diagnosed ITP patients. Newly diagnosed ITP patients and healthy volunteers were enrolled to assess the numbers of peripheral Th1, Th17 cells and Tregs. CD4(+)CD25(-)Teffs and CD4(+)CD25(+)Tregs were purified. CD4(+)CD25(-)Teffs, labeled with CFSE, were cultured alone or with Tregs for 5 days, and the supernatants were then collected for IL-10 concentration test. The role of IL-10 in Tregs' inhibitory function was also determined. In ITP patients, Teffs were excessively activated, while the Tregs were numerically and functionally impaired. The percentages of IL-10(+) Tregs in Tregs' population were found elevated dramatically in ITP patients but decreased in the remitted patients. The IL-10 concentrations in the cultured supernatant were decreased in ITP patients but elevated in the remitted patients. Furthermore, the IL-10 secretion by Tregs was dramatically decreased in ITP patients. IL-10 treatment enhanced the suppression effect of Tregs toward Teffs, whereas anti-IL-10 treatment boosted the proliferation of Teffs and Th17 cells. Excessive activated Teffs and impaired Tregs play major roles in the exuberant CD4(+) T cells immune responses of ITP. The inhibitory effect of Tregs toward Teffs is largely exerted by IL-10. Insufficient secretion of IL-10 compromises the inhibitory capability of Tregs against Teffs in newly diagnosed ITP patients.
authors.affiliation: Department of Hematology, Zhongshan Hospital, Fudan University, 180 Fenglin Rd, Shanghai, 200032, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Lili
authors.initials: L
authors.lastname: Ji
authors.forename: Weiguang
authors.initials: W
authors.lastname: Wang
authors.forename: Fanli
authors.initials: F
authors.lastname: Hua
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Zhan
authors.forename: Shanhua
authors.initials: S
authors.lastname: Zou
authors.forename: Ling
authors.initials: L
authors.lastname: Yuan
authors.forename: Yang
authors.initials: Y
authors.lastname: Ke
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Min
authors.forename: Dongli
authors.initials: D
authors.lastname: Song
authors.forename: Lihua
authors.initials: L
authors.lastname: Sun
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Cheng
mesh_terms: D000328:Adult; D000368:Aged; D015551:Autoimmunity; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007165:Immunosuppression Therapy; D016753:Interleukin-10 / Q000378:metabolism*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D055815:Young Adult
chemical_list: D016753:Interleukin-10