Regulatory role of ceRNA network in B lymphocytes of patients with immune thrombocytopenia.

OBJECTIVE: High-throughput sequencing was used to screen expressing differences of miRNA, lncRNA, and mRNA in CD19+ B peripheral blood samples of newly diagnosed immune thrombocytopenia (ITP) patients and healthy controls. The study aimed to explore the regulatory role of ceRNA network in the pathogenesis of dysfunctional CD19 + B lymphocytes of ITP patients. METHODS: CD19+ B lymphocytes were isolated from peripheral blood samples of ITP patients and their healthy counterparts. High-throughput sequencing was used to screen for the expression of miRNA, lncRNA, and mRNA of ITP patients and healthy controls, which were analysed by the ceRNA network. Moreover, qPCR was used to verify the differential expression of miRNA, lncRNA, and mRNA in ITP patients and healthy controls. The correlation between differentially expressed miRNA, lncRNA, mRNA, and B lymphocyte subsets was also analysed. RESULTS: The CD19+ B lymphocytes of 4 newly diagnosed ITP patients and 4 healthy controls were sequenced and analysed. There were 65 differentially expressed lncRNA and 149 mRNA forming a ceRNA network showed that 12 lncRNA and 136 differentially expressed mRNA were closely associated. Similarly, miR-144-3p, miR-374c-3p, and miR-451a were highly expressed in ITP patients, as confirmed by qPCR, which was consistent with the high-throughput sequence results. LOC102724852 and CCL20 were highly expressed in ITP patients, while LOC105378901, LOC112268311, ALAS2, and TBC1D3F were not as compared to healthy controls, which was consistent with the high-throughput sequence results. In addition, the expression of miR-374c-3p, LOC112268311, LOC105378901, and CXCL3 were correlated with the percentage of B lymphocyte subsets. CONCLUSIONS: The ceRNA network of miRNA, lncRNA, and mRNA in peripheral CD19 + B lymphocytes plays an essential role in the pathogenesis of ITP.

Efficacy and quality of life of Romiplostim in adults and children with immune thrombocytopenia: A review.

BACKGROUND: To systematically evaluate the clinical efficacy, drug safety and health-related quality of life (HRQoL) of Romiplostim in adult and child immune thrombocytopenia (ITP) patients. METHODS: PubMed, EMBASE and Cohrane library databases were searched for all randomized controlled trials published until 2022, and the Review Manager 5.3 was used for meta-analysis. RESULTS: A total of 9 randomized controlled trials were included in this study. The results of meta-analysis showed that the total platelet response rate and long-term platelet response rate in treatment group were significantly higher than those in control group (P<0.05). There was no statistical significance in the side effects, serious side effects, bleeding events and serious bleeding events between 2 groups (P>0.05). Compared with control group, the HRQoL in ITP adults and children, and parents of ITP children had no statistical significance (P>0.05). CONCLUSION: Romiplostim has a certain clinical efficacy in ITP adults and children, and relatively small adverse drug reactions. The improvement of Romiplostim on HRQoL in ITP adults and children is not clear.

Bone marrow free immune checkpoints as a potential biomarker for differential diagnosis of acquired bone marrow failures.

OBJECTIVE: Clinically, to make a definite diagnosis of aplastic anemia (AA), idiopathic cytopenia of undetermined significance (ICUS) or myelodysplastic syndrome (MDS), they should be distinguished from each other. AA and ICUS have some incidence to transform into MDS. Immunosuppressive therapy (IST) is effective in AA and partial ICUS patients, while other ICUSs are more likely to progress to MDS without response to IST. To date, we neither found a technical method that could easily identify AA from hypoproliferative MDS, nor a simple parameter that could indicate ICUS with a response to IST. Here, we detected the concentration of free immune checkpoints in bone marrow supernatant of AA, ICUS, and MDS patients, analyzed the differences of immune status among these three diseases, to try to find a way to predict the response to IST in ICUSs. METHODS: Seventy-four novel patients were enrolled with newly diagnosed acquired bone marrow failure (including 29 AA patients, 11 ICUS patients, and 34 MDS patients), bone marrow supernatants were collected. Luminex liquid suspension array technology was used to measure the concentrations of 17 immune checkpoints to analyze the differences of immune status among these three diseases. RESULTS: The levels of 17 free immune checkpoints were elevated in MDS and showed a strong correlation with each other, followed by ICUS, and with the weakest in AA. By drawing the ROC curve, we found eight immune checkpoints, including sCD40, sCD86/B7-2, sCTLA-4, sGITR, sHVEM, sPD-1, sTIM-3, and sTLR-2, could easily distinguish AA from hypoproliferative MDS. ICUSs with lower concentrations of these eight free immune checkpoints predicted a better IST response. CONCLUSION: In conclusion, we found that there were notable differences in the immune status of AA, ICUS, and MDS. The concentrations of sCD40, sCD86/B7-2, sCTLA-4, sGITR, sHVEM, sPD-1, sTIM-3, and sTLR-2 could be used to identify AA and hypoproliferative MDS patients, as well as to distinguish ICUS patients who could benefit from IST.

MicroRNA-21-5p Regulates CD3+T Lymphocytes Through VCL and LTF in Patients with Immune Thrombocytopenia.

BACKGROUND: Immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease with distinct clinical manifestations such as extensive skin petechiae, mucosal bleeding, and even visceral hemorrhage. In this study, CD3+T lymphocytes from ITP patients were screened for differentially expressed genes. The expression of miR-21 and miR-155 in T lymphocytes of ITP patients were investigated. The downstream target genes of miR-21 and miR-155 were also searched for the correlation between differentially expressed genes of ITP. METHODS: Differential gene screening was performed using the GSE43177 data set in the GEO database, and the expression of miR-21 and miR-155 in T lymphocytes of ITP patients was verified by qPCR. The interaction network of core downstream target genes and ITP differentially expressed genes of miR-21 and miR-155 were constructed with the STRING database, and the associated factors were verified by qPCR. RESULTS: In ITP patients, the expression of CD8+T lymphocytes increased, the expression of CD4+T lymphocytes decreased, and the ratio of CD4+/CD8+T cells decreased. Fourteen genes were differentially expressed in CD3+T lymphocytes, all of which were upregulated, and the expression of S100A8 was increased in ITP patients. The expression of miR-21-5p and miR-155-5p increased in CD3+T lymphocytes of initial ITP patients. The core down-stream target gene VCL of miR-21 was associated with the differentially expressed genes such as LTF, LCN2, and DEFA4 in the interaction network. VCL expression was decreased and LTF expression was increased in ITP patients. CONCLUSIONS: S100A8 plays an important role in the regulation of CD3+T lymphocytes in ITP patients. MiR-21-5p regulates the differentially expressed gene LTF by inhibiting the core downstream target gene VCL and participates in the immune mechanism of T lymphocytes in ITP patients. MiR-155-5p is also involved in the immunoregulatory mechanism of T lymphocytes in ITP patients.

Myeloid dendritic cells in severe aplastic anemia patients exhibit stronger phagocytosis.

BACKGROUND: A deeper understanding of the pathogenesis of severe aplastic anemia (SAA) is urgently warranted to achieve better therapeutic effects. The objective of this study was to investigate the phagocytosis of myeloid dendritic cell (mDC) in SAA patients. METHODS: Myeloid dendritic cells were induced in vitro from bone marrow mononuclear cells from 26 SAA patients and 12 normal controls (HCs). The phagocytosis of mDCs was detected by flow cytometry using FITC-Dextran (40KD), and its correlation with the immune status and severity of the disease was analyzed. RESULTS: The phagocytosis of mDC from untreated SAA patients was significantly stronger than that from complete remission group and HC group (p < 0.05). There was no statistical difference between the latter two groups (p > 0.05). The phagocytosis of mDC from SAA patients correlated positively with the concentration of interleukin (IL)-2 (r = 0.389, p < 0.05), and IL-4 (r = 0.556, p < 0.05), negatively with CD4+ /CD8+ ratio (r = -0.421, p < 0.05). It also had negative correlations with the level of hemoglobin (r = -0.393, p < 0.05), white blood cell (r = -0.436, p < 0.05), platelet (r = -0.431, p < 0.05), and reticulocyte (r = -0.447, p < 0.05). The phagocytosis of mDC does not correlate with the response to IST. CONCLUSIONS: The increased phagocytosis of mDC in untreated SAA patients may contribute to abnormal activation of T helper (Th) and subsequent cytotoxic T lymphocyte (CTL) activation in these patients. It may be involved in the immune pathogenesis of SAA.

Plasma Metabolomic and Intestinal Microbial Analyses of Patients With Severe Aplastic Anemia.

Aplastic anemia results from bone marrow failure caused by an autoimmune abnormality, but the pathogenesis of severe aplastic anemia (SAA) is not well characterized. To identify potential metabolic markers of SAA and to further elucidate the pathogenetic mechanisms of SAA, we performed a metabolomic study of plasma samples and characterized the intestinal microbiota of patients with SAA and healthy controls. Patients with SAA had more Enterobacteriales and Lactobacillales, but fewer Bacteroidales, Clostridiales, and Erysipelotrichales than healthy controls. At the species level, the abundances of Escherichia coli and others including Clostridium citroniae were higher, whereas those of Prevotella copri, Roseburia faecis, and Ruminococcus bromii were lower. Eight metabolites showed significantly different plasma concentrations in the SAA and healthy control groups. Coumaric acid, L-phenylalanine, and sulfate were present at higher concentrations in the SAA group; whereas L-glutamic γ-semialdehyde, theobromine, 3a, 7a-dihydroxy-5b-cholestane, γ-δ-dioxovaleric acid, and (12Z)-9, 10-dihydroxyoctadec-12-enoic acid were present at lower concentrations. In conclusion, patients with SAA show abnormalities in both their plasma metabolomes and intestinal microbial compositions. These differences might reflect the molecular mechanisms involved in the defective immunity that characterizes SAA.

Immunological characteristics and effect of cyclosporin in patients with immune thrombocytopenia.

OBJECTIVE: Immune thrombocytopenia (ITP) is well-known as an antibody-mediated autoimmune disease, and it is easy to get response but often turns to relapse or refractory. Cyclosporin is a traditional immunosuppressant and had a good effect on ITP patients. In this paper, we retrospectively analyze the immunological characteristics and therapeutic effect of cyclosporin in 220 patients with ITP. METHODS: All newly diagnosed ITP patients in the Department of Hematology, Tianjin Medical University General Hospital from June 2018 to December 2020 were enrolled and divided into four groups according to the expression of autoantibodies and the occurrence of prodromal infection. The basic data and immune indexes of ITP patients in each group were collected. The clinical immunological characteristics of patients in each group and the therapeutic effect of cyclosporin in each group were analyzed. RESULTS: Multi-autoantibody ITP patients were more likely to have low serum albumin and high gamma globulin, and the ratio of albumin to globulin decreased. In addition, the level of IgA and IgG increased and the level of complement C3 and C4 decreased more frequently than those in other groups. The number of CD3+T lymphocytes, especially CD3+CD4+T lymphocytes, decreased in ANA+ITP patients. The number of CD16+CD56+NK cells, pDC/DC ratio, and pDC/mDC ratio were higher than those in other groups. The expression of IL-6 and the proportion of CD19+B lymphocytes increased in two groups of ITP patients with abnormal autoantibodies. The patients of pro-infected group were more likely to suffer from coagulation disorder. After treatment with cyclosporin, the response rate increased and the 3-month relapse rate decreased in all ITP patients, and the therapeutic effect of patients with high megakaryocyte number was significantly higher than that of patients with low megakaryocyte number. The impact factors that influence the effect of glucocorticoid and(or) IVIG were the number of CD3+CD8+T lymphocytes, CD4/CD8 cell ratio, and the number of CD19+B lymphocytes. The independent impact factor of cyclosporin therapeutic response rate was the number of CD3+T lymphocytes. CONCLUSIONS: ITP is a heterogeneous disease, recurrence may occur during or rapidly after treatment. Cyclosporine included treatment can improve the effective rate of ITP and reduce the relapse rate within 3 months. The number of CD3+T lymphocytes was the only impact factor that influence the therapeutic effect of cyclosporin in ITP patients.