sq-23377 and Purpura--Thrombocytopenic--Idiopathic

Regulatory B cells (Breg) are a distinct B cell subset with immunoregulatory properties. Pivotal to Breg function is interleukin-10. This study was to investigate the role of IL-10-producing B cell (B10) and its association with Treg and Th17 subsets in immune thrombocytopenia (ITP) patients.. Peripheral blood mononuclear cells from ITP patients and controls were stimulated with PMA, ionomycin, and Brefeldin A. The frequencies of CD19(+)IL-10(+) B cells, CD3(+)CD4(+)IL-17(+) Th17 cells, and CD4(+)CD25(hi)Foxp3(+) Treg cells were analyzed by flow cytometry. The mRNA expression of Foxp3 and RORγt was detected by real-time quantitative PCR.. The number of B10 cells was elevated in ITP patients. After first-line therapies, it remained at high level in patients who achieved complete or partial response but decreased in those who acquired no response. There was a positive correlation between B10 cells and Tregs in ITP both before and after therapies. The ratio of Treg/Th17 decreased in ITP, and it strongly correlated with B10 cells.. The frequency of B10 cells is elevated in ITP and it correlates with both the Tregs counts and the Treg/Th17 ratio. B10 cells to regulate functional T cell subsets might be impaired in patients with ITP.

Topics: Adult; Aged; Antigens, CD19; B-Lymphocytes; Brefeldin A; CD3 Complex; CD4-Positive T-Lymphocytes; Female; Flow Cytometry; Humans; Interleukin-10; Interleukin-17; Interleukin-2 Receptor alpha Subunit; Ionomycin; Leukocytes, Mononuclear; Male; Middle Aged; Phorbol Esters; Polymerase Chain Reaction; Purpura, Thrombocytopenic, Idiopathic; Th17 Cells; Treatment Outcome; Young Adult

Chronic immune thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by increased platelet clearance because of antiplatelet antibodies. It was recently reported that the balance of T helper 1 (Th1) and T helper 2 (Th2) subsets has been implicated in the regulation of many immune responses. In this study, the intracellular interleukin-4 and interferon-gamma production in CD4+ T-lymphocytes activated by phorbol 12-myristate 13-acetate and ionomycin was assessed via flow cytometry in order to determine the clinical significance of the Th1/Th2 ratio in 42 patients with ITP. The study cohort included 28 untreated patients, seven postprednisolone therapy patients and seven postsplenectomy patients. The mean level of the Th1/Th2 ratio in the untreated group was 36.9 (95% CI 25.8-47.9), and significantly higher than in the control group (mean 12.8, 95% CI 9.5-16.1). The mean levels of the Th1/Th2 ratio in the postprednisolone therapy and postsplenectomy groups were 20.5 (95% CI 8.4-32.6) and 16.4 (95% CI 3.1-29.7), respectively, but were no significant differences as compared with control subjects. When untreated patients were divided into two subgroups by Th1/Th2 ratio, the mean level of platelet associated IgG in the high Th1/Th2 subgroup (higher than upper limit of control group) tended to be higher than in the normal Th1/Th2 subgroup. In conclusion, the high Th1/Th2 ratio was closely related to the etiology and disease status of chronic ITP.

Topics: Adult; Aged; Case-Control Studies; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Chronic Disease; Cohort Studies; Cytokines; Female; Flow Cytometry; Humans; Immunoglobulin G; Ionomycin; Ionophores; Male; Middle Aged; Prednisolone; Purpura, Thrombocytopenic, Idiopathic; Tetradecanoylphorbol Acetate; Th1 Cells; Th2 Cells; Time Factors