BACKGROUND: Macrophage polarization anomalies and dysfunction play a crucial role in the pathogenesis of immune thrombocytopenia (ITP). Itaconate is a Krebs cycle-derived immunometabolite synthesized by myeloid cells to modulate cellular metabolism and inflammatory responses. This study aimed to evaluate the immunoregulatory effects of an itaconate derivative on macrophages in patients with ITP. METHODS: Peripheral blood-derived macrophages from patients with ITP and healthy controls were treated with 4-octyl itaconate (4-OI), a derivative of itaconate that can penetrate the cell membrane. Macrophage polarization, antigen-presenting functions, and phagocytic capability were measured via flow cytometry and enzyme-linked immunosorbent assay (ELISA). Macrophage glycolysis in patients with ITP and the metabolic regulatory effect of 4-OI were detected using a Seahorse XFe96 Analyzer. An active murine model of ITP was used to evaluate the therapeutic effects of 4-OI in vivo . RESULTS: 4-OI reduced the levels of CD80 and CD86 in M1 macrophages and suppressed the release of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 pro-inflammatory cytokines, suggesting that 4-OI could hinder the polarization of macrophages toward an M1 phenotype. We found that 4-OI pretreated M1 macrophages reduced the proliferation of CD4 + T cells and promoted the differentiation of regulatory T cells. In addition, after 4-OI treatment, the phagocytic capacity of M1 macrophages toward antibody-coated platelets decreased significantly in patients with ITP. In addition, the glycolytic function of M1 macrophages was elevated in individuals with ITP compared to those in healthy controls. 4-OI treatment downregulated glycolysis in M1 macrophages. The glycolysis inhibitor 2-deoxy-d-glucose (2-DG) also inhibited the polarization of M1 macrophages and restored their functions. In vivo , 4-OI treatment significantly increased platelet counts in the active ITP murine model. CONCLUSIONS Itaconate derivative 4-OI inhibited M1 macrophage polarization and restored impaired functions through metabolic reprogramming. This study provides a novel therapeutic option for ITP.
Macrophages/metabolism* ; Humans ; Animals ; Succinates/pharmacology* ; Mice ; Male ; Female ; Adult ; Middle Aged ; Flow Cytometry ; Tumor Necrosis Factor-alpha/metabolism* ; Enzyme-Linked Immunosorbent Assay ; Purpura, Thrombocytopenic, Idiopathic/metabolism* ; Glycolysis/drug effects* ; Metabolic Reprogramming

Objective This study investigated the regulatory effect of high mobility group protein B1 (HMGB1) in the peripheral blood of patients with primary immune thrombocytopenia (ITP) on myeloid dendritic cells (mDC) and Th17/regulatory T cells (Treg) balance. Methods The study enrolled 30 newly diagnosed ITP patients and 30 healthy controls.Flow cytometry was used to measure the proportion of mDC, Th17, and Treg cells in the peripheral blood of ITP patients and healthy controls. ELISA was conducted to quantify the serum levels of HMGB1, interleukin 6 (IL-6), IL-23, IL-17, and transforming growth factor β(TGF-β). The mRNA levels of retinoic acid-related orphan receptor γt(RORγt) and forehead box P3(FOXP3) were detected by real-time PCR. The correlation between the abovementioned cells, cytokines, and platelet count was assessed using Pearson linear correlation analysis. Results The proportion of Th17 cells and the expression levels of HMGB1, IL-6, IL-23, IL-17 and the level of RORγt mRNA in the peripheral blood of ITP patients were higher than those in healthy controls. However, the Treg cell proportion and TGF-β level were lower in ITP patients than those in healthy controls. In patients with ITP, the proportion of mDC and the level of FOXP3 mRNA did not show significant changes. The proportion of mDC cells was significantly correlated with the expression of IL-6 and IL-23. Moreover, the expression of HMGB1 showed a significant correlation with the expression of mDC, IL-6, IL-23, RORγt mRNA, and IL-17. Notably, both the proportion of mDC cells and the expression of HMGB1 were negatively correlated with platelet count. Conclusion The high expression of HMGB1 in peripheral blood of ITP patients may induce Th17/Treg imbalance by promoting the maturation of mDC and affecting the secretion of cytokines, thereby potentially playing a role in the immunological mechanism of ITP.
Humans ; Th17 Cells/cytology* ; HMGB1 Protein/genetics* ; T-Lymphocytes, Regulatory/cytology* ; Female ; Male ; Dendritic Cells/metabolism* ; Adult ; Middle Aged ; Purpura, Thrombocytopenic, Idiopathic/genetics* ; Nuclear Receptor Subfamily 1, Group F, Member 3/genetics* ; Young Adult ; Interleukin-23/blood* ; Interleukin-17/blood* ; Interleukin-6/blood* ; Forkhead Transcription Factors/genetics* ; Myeloid Cells/cytology* ; Aged

OBJECTIVES: To investigate the expression of interleukin-37 (IL-37), vascular endothelial growth factor A (VEGFA), and transforming growth factor-β1 (TGF-β1) in children with primary immune thrombocytopenia (ITP) and their correlation with T cells. METHODS: A retrospective analysis was conducted on 45 children with ITP (ITP group) who were admitted to Handan Central Hospital from January 2020 to April 2022, and 30 healthy children who underwent physical examination during the same period were included as the healthy control group. The mRNA expression levels of IL-37, VEGFA, and TGF-β1 and the levels of regulatory T cells (Treg) and helper T cells 17 (Th17) were measured before and after treatment, and the correlation between the mRNA expression levels of IL-37, VEGFA, and TGF-β1 and the levels of Treg, Th17, and Treg/Th17 ratio were analyzed. RESULTS: Compared with the healthy control group, the ITP group had a significantly higher mRNA expression level of IL-37 and a significantly higher level of Th17 before and after treatment, as well as significantly lower mRNA expression levels of VEGFA and TGF-β1 and significantly lower levels of Treg and Treg/Th17 ratio (P<0.05). After treatment, the ITP group had significant reductions in the mRNA expression level of IL-37 and the level of Th17 and significant increases in the mRNA expression levels of VEGFA and TGF-β1 and the levels of Treg and Treg/Th17 ratio (P<0.05). Correlation analysis showed that in the ITP group, the mRNA expression levels of IL-37 and TGF-β1 were negatively correlated with the levels of Treg and Treg/Th17 ratio (P<0.05) and were positively correlated with the level of Th17 (P<0.05) before and after treatment; the mRNA expression level of VEGFA was positively correlated with the levels of Treg and Treg/Th17 ratio (P<0.05) and was negatively correlated with the Th17 level (P<0.05) before and after treatment. CONCLUSIONS Abnormal expression levels of IL-37, VEGFA, and TGF-β1 may be observed in children with ITP, which is significantly associated with the imbalance of Treg/Th17 ratio. It is speculated that the cytokines such as IL-37, VEGFA, and TGF-β1 may be involved in the development and progression of ITP or may become important potential targets for the treatment of children with ITP. Citation:Chinese Journal of Contemporary Pediatrics, 2023, 25(11): 1131-1136.
Child ; Humans ; Interleukins ; Purpura, Thrombocytopenic, Idiopathic ; Retrospective Studies ; RNA, Messenger/metabolism* ; T-Lymphocytes, Regulatory ; Th17 Cells/metabolism* ; Transforming Growth Factor beta1/genetics* ; Vascular Endothelial Growth Factor A/genetics*

OBJECTIVE: To investigate the expression of programmed death receptor-1 (PD-1) and inducible costimulator (ICOS) on the surface of CD8⁺ T cells in peripheral blood of patients with primary immune thrombocytopenia (ITP), and explore the roles of PD-1 and ICOS in the occurrence and development of ITP. METHODS: A total of 28 ITP patients treated in Tianjin Medical University General Hospital from September to December 2020 were selected, including 13 patients with newly diagnosed ITP, 15 patients with chronic ITP, and 22 healthy volunteers were recruited as control group. Flow cytometry was used to detect the expression levels of PD-1 and ICOS, and evaluate their correlation with clinical indicators. RESULTS: The percentage of CD8 ⁺ T cells in ITP patients of chronic group was higher than that of the newly diagnosed group and the control group (P<0.05). The expression level of PD-1 on CD8⁺ T cells in ITP patients of newly diagnosed group and chronic group were significantly lower than that of the control group (P<0.05), while the expression level of ICOS were significantly higher (P<0.05). In ITP patients, PD-1 was negatively correlated with platelet count (r=-0.4942, P<0.01), but positively with ICOS (r=0.4342). PD-1 and ICOS were both negatively correlated with lymphocyte count (r_PD-1=-0.4374; r_ICOS=-0.4492). CONCLUSION In ITP patients, the unbalanced expression of PD-1 and ICOS may interfere with the immune homeostasis of the body, which can be used as a therapeutic target for ITP patients.
CD8-Positive T-Lymphocytes/metabolism* ; Flow Cytometry ; Humans ; Inducible T-Cell Co-Stimulator Protein/metabolism* ; Platelet Count ; Programmed Cell Death 1 Receptor/metabolism* ; Purpura, Thrombocytopenic, Idiopathic

The gut microbiota is an important part of the human body, and it's also the largest genome in the human body. Recent studies on the gut microbiota have found that it plays an important role in human immune diseases. In recent years, the methods of sequencing gut microbiota has teen improved, thus dysregulation of the gut microbiota is found in many immune diseases, and the most widely studied mechanism is the short-chain fatty acids (SCFA), which is a metabolite of gut microbiota. The role of short-chain fatty acids in intestinal barrier, IgA immunity, dendritic cells and regulatory T cells has become increasingly clear. The mechanisms of short-chain fatty acids in regulating immunity and its role in the pathogenesis of immune thrombocytopenia were covered in this review, so as to provide a new idea for the treatment of immune thrombocytopenia in the future.
Adolescent ; Fatty Acids, Volatile/metabolism* ; Gastrointestinal Microbiome ; Humans ; Intestines ; Purpura, Thrombocytopenic, Idiopathic

OBJECTIVETo explore the role of Treg cells in the pathogenesis of idiopathic thrombocytopenic purpura (ITP).

METHODSThe ITP mouse model was established, the Treg cell ratio in peripheral blood and spleen was detected by flow cytometry, the CD4+ CD25+ T cells were sorted by immunomagnetic beads, the Treg cell associated transcription factors (Foxp3, Smad7, STAT5 and Akt-1) and cytokines (IL-10, TGF-β) in CD4+ CD25+ T cells were enriched from spleen mononuclear cells, and the mRNA expression of Treg cell was measured by real-time PCR.

RESULTSThe ratio of Tregs in peripheral blood and spleen decreased significantly in ITP mouse, as compared with the controls (P<0.01). In addition, the mRNA expression of IL-10, TGF-β and Foxp3 decreased significantly in spleen CD4+ CD25+ T cells (P<0.05). Expression of Smad 7 mRNA was higher than that of controls.

CONCLUSIONThe alteration in Treg frequency and function may be responsible for the immune dysfunction in ITP disease. It is also speculated that the lower mRNA expression of Foxp3 and higher mRNA expression of Smad 7 may inhibit the proliferation and differentiation of Treg cells.

Animals ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Interleukin-10 ; metabolism ; Mice ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; pathology ; RNA, Messenger ; metabolism ; Real-Time Polymerase Chain Reaction ; Smad7 Protein ; metabolism ; Spleen ; cytology ; T-Lymphocytes, Regulatory ; cytology ; Transforming Growth Factor beta ; metabolism

OBJECTIVETo investigate the expression of IL- 23/IL- 17 axis in peripheral blood of patients with primary immune thrombocytopenia （ITP） and its clinical significance.

METHODSThe real-time quantitative reverse transcription-polymerase chain reaction（RT-PCR）was used to determine the expression of IL-23p19, p40, p35, IL-23R, IL-12Rβ1, IL-12Rβ2, IL-17A, IL-17F mRNA in the peripheral blood of 45 ITP patients and 30 healthy controls. The correlations between the expression of IL-23 and IL- 17, platelet counts, serum cytokine concentrations of ITP patients were analyzed. Furthermore, nine newly diagnosed ITP patients were followed up during treatment.

RESULTSThe gene expressions of IL-23p19, p40, IL-23R, IL-12Rβ1, IL-17A, IL-17F in ITP patients were significantly higher than those in healthy controls, the relative expression levels of ITP were 5.58, 2.13, 4.20, 2.45, 4.29, 2.50 times as much as that of healthy controls. And elevated serum IL-23［（198.70±94.56）ng/L vs（50.72±22.97）ng/L, t= 10.06, P<0.001］, IL-17［（85.25±21.97）ng/L vs（11.39±4.27）ng/L, t=21.94，P<0.001］levels were also observed in these ITP patients. In addition, the serum IL-23 level in ITP patients was positively correlated with IL-17（r=0.496, P<0.01）, but negatively correlated with the platelet counts（r=-0.408, P<0.01）, and IL-17 level was negatively correlated with platelet counts（r=-0.464, P<0.01）.

CONCLUSIONThe IL-23/IL- 17 expression in ITP patients was significantly elevated, indicating IL-23/IL-17 play an important role in the pathogenesis of ITP.

Case-Control Studies ; Cytokines ; blood ; Gene Expression ; Humans ; Interleukin-17 ; metabolism ; Interleukin-23 ; metabolism ; Platelet Count ; Purpura, Thrombocytopenic, Idiopathic ; metabolism ; RNA, Messenger

Adult ; Cell Proliferation ; Female ; Humans ; Interleukins ; blood ; Leukocytes, Mononuclear ; cytology ; metabolism ; Male ; Middle Aged ; Purpura, Thrombocytopenic, Idiopathic ; blood ; Young Adult

OBJECTIVETo explore the expression and clinical significance of T cell immunoglobulin mucin (TIM)-1, TIM-3 and T cell-specific transcription factors T-bet and GATA-3 in spleen mononuclear cells in patients with primary immune thrombocytopenia (ITP).

METHODSThe spleen samples were obtained from 17 active ITP patients and 10 controls with spleen traumatic rupture. By using real-time quantitative polymerase chain reaction, the mRNA expressions of TIM-3, TIM1, T-bet and GATA-3 were studied in all subjects.

RESULTSTIM-3 mRNA levels of active ITP patients were significantly decreased to (29 ± 16)% of that of control, TIM-1 mRNA levels of active ITP patients increased to (3.20 ± 2.18) folds of that of control, but the difference was not significant. The ratio of TIM-1/ TIM-3 was elevated in active ITP patients. T-bet mRNA levels were up-regulated in ITP patients by (2.82 ± 1.57) folds (P<0.05) and the expression of GATA3 was decreased by 14% folds (P<0.05) compared to controls. The ratio of T-bet/GATA3 were significantly elevated in ITP patients.

CONCLUSIONThe imbalance between TIM-3 and TIM-1 expression might play an important role in pathogenesis of ITP.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Case-Control Studies ; Female ; Flow Cytometry ; GATA3 Transcription Factor ; metabolism ; Hepatitis A Virus Cellular Receptor 1 ; Hepatitis A Virus Cellular Receptor 2 ; Humans ; Male ; Membrane Glycoproteins ; metabolism ; Membrane Proteins ; metabolism ; Middle Aged ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; metabolism ; RNA, Messenger ; genetics ; Receptors, Virus ; metabolism ; Spleen ; metabolism ; Th1 Cells ; immunology ; Th2 Cells ; immunology ; Young Adult

Defective dendritic cell (DC) functions have been implicated in ITP. The purpose of this study was to investigate the distribution and activation of dendritic cells in immune thrombocytopenia (ITP) patients. ITP patients were divided into 3 groups: the newly diagnosed, refractory and effective treatment group. The distributions of plasmacytoid dendritic cells (pDC) and myeloid dendritic cells (mDC) in peripheral blood, bone marrow and spleen were detected with flow cytometry. The expression level of CD80 and CD86 on surface of pDC and mDC was also detected with flow cytometry. The results indicated that the percentage of mDC was higher than that of pDC in all sites of all groups. The percentage of mDC and pDC in all site of refractory group was higher than that in newly diagnosed and effective groups, but the percentage of mDC in spleen of refractory group was obviously higher than that in other sites. The percentage of pDC was no significant different in all groups. The expression level of CD86 in all groups was higher than that of CD80, the expression level of CD80 was lower in mDC and pDC of all groups, but there was no obvious difference in all sites. The CD86 expression in all site of refractory group was higher than that in newly diagnosed and effective treatment groups, while the CD86 expression of mDC in spleen of newly diagnosed group obviously higher than that in other sites. It is concluded that the distribution abnormality of mDC and pDC exists in ITP patients, the mDC are more accumulated in spleen, and differentiation of mDC to maturity is more obvious in spleen, spleen-derived mDC significantly express CD86, spleen-derived mDC may play an important role in the pathogenesis of ITP.
Adult ; B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; Dendritic Cells ; cytology ; immunology ; Female ; Humans ; Male ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; Spleen ; cytology