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1.
Signal Transduct Target Ther ; 9(1): 102, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653983

RESUMO

Patients with refractory immune thrombocytopenia (ITP) frequently encounter substantial bleeding risks and demonstrate limited responsiveness to existing therapies. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) present a promising alternative, capitalizing on their low immunogenicity and potent immunomodulatory effects for treating diverse autoimmune disorders. This prospective phase I trial enrolled eighteen eligible patients to explore the safety and efficacy of UC-MSCs in treating refractory ITP. The research design included administering UC-MSCs at escalating doses of 0.5 × 106 cells/kg, 1.0 × 106 cells/kg, and 2.0 × 106 cells/kg weekly for four consecutive weeks across three cohorts during the dose-escalation phase, followed by a dose of 2.0 × 106 cells/kg weekly for the dose-expansion phase. Adverse events, platelet counts, and changes in peripheral blood immunity were monitored and recorded throughout the administration and follow-up period. Ultimately, 12 (with an addition of three patients in the 2.0 × 106 cells/kg group due to dose-limiting toxicity) and six patients were enrolled in the dose-escalation and dose-expansion phase, respectively. Thirteen patients (13/18, 72.2%) experienced one or more treatment emergent adverse events. Serious adverse events occurred in four patients (4/18, 22.2%), including gastrointestinal hemorrhage (2/4), profuse menstruation (1/4), and acute myocardial infarction (1/4). The response rates were 41.7% in the dose-escalation phase (5/12, two received 1.0 × 106 cells/kg per week, and three received 2.0 × 106 cells/kg per week) and 50.0% (3/6) in the dose-expansion phase. The overall response rate was 44.4% (8/18) among all enrolled patients. To sum up, UC-MSCs are effective and well tolerated in treating refractory ITP (ClinicalTrials.gov ID: NCT04014166).


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Púrpura Trombocitopênica Idiopática , Humanos , Feminino , Masculino , Púrpura Trombocitopênica Idiopática/terapia , Púrpura Trombocitopênica Idiopática/imunologia , Pessoa de Meia-Idade , Adulto , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Células-Tronco Mesenquimais/imunologia , Cordão Umbilical/citologia , Estudos Prospectivos , Idoso
2.
Haemophilia ; 30 Suppl 3: 21-28, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38571362

RESUMO

Registries are excellent sources of data to address questions that are typically not evaluated in randomized clinical trials, including natural history, disease prevalence, treatment approaches and adverse events, and models of care. Global and regional registries can provide data to identify differences in outcomes and in haemophilia care between countries, economic settings, and regions, while facilitating research and data sharing. In this manuscript, we highlight five bleeding disorder registries: Country registries from Australia and China, Paediatric Network on Haemophilia Management (PedNet) data on children who have received emicizumab, data from the European Haemophilia Safety Surveillance (EUHASS) system, and data on women and girls with haemophilia from the World Federation of Haemophilia (WFH) registries. Data from these and other bleeding disorder registries have been and will continue to be used to advance patient care, understand treatment patterns and adverse reactions, and identify areas of increased need and focus.


Assuntos
Hemofilia A , Humanos , Feminino , Criança , Hemofilia A/tratamento farmacológico , Sistema de Registros , China , Prevalência , Austrália/epidemiologia
5.
Br J Haematol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513635

RESUMO

This study aimed to identify key proteomic analytes correlated with response to splenectomy in primary immune thrombocytopenia (ITP). Thirty-four patients were retrospectively collected in the training cohort and 26 were prospectively enrolled as validation cohort. Bone marrow biopsy samples of all participants were collected prior to the splenectomy. A total of 12 modules of proteins were identified by weighted gene co-expression network analysis (WGCNA) method in the developed cohort. The tan module positively correlated with megakaryocyte counts before splenectomy (r = 0.38, p = 0.027), and time to peak platelet level after splenectomy (r = 0.47, p = 0.005). The blue module significantly correlated with response to splenectomy (r = 0.37, p = 0.0031). KEGG pathways analysis found that the PI3K-Akt signalling pathway was predominantly enriched in the tan module, while ribosomal and spliceosome pathways were enriched in the blue module. Machine learning algorithm identified the optimal combination of biomarkers from the blue module in the training cohort, and importantly, cofilin-1 (CFL1) was independently confirmed in the validation cohort. The C-index of CFL1 was >0.7 in both cohorts. Our results highlight the use of bone marrow proteomics analysis for deriving key analytes that predict the response to splenectomy, warranting further exploration of plasma proteomics in this patient population.

6.
Br J Haematol ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438130

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by antibody-mediated platelet destruction and impaired platelet production. The mechanisms underlying ITP and biomarkers predicting the response of drug treatments are elusive. We performed a metabolomic profiling of bone marrow biopsy samples collected from ITP patients admission in a prospective study of the National Longitudinal Cohort of Hematological Diseases. Machine learning algorithms were conducted to discover novel biomarkers to predict ITP patient treatment responses. From the bone marrow biopsies of 91 ITP patients, we quantified a total of 4494 metabolites, including 1456 metabolites in the positive mode and 3038 metabolites in the negative mode. Metabolic patterns varied significantly between groups of newly diagnosed and chronic ITP, with a total of 876 differential metabolites involved in 181 unique metabolic pathways. Enrichment factors and p-values revealed the top metabolically enriched pathways to be sphingolipid metabolism, the sphingolipid signalling pathway, ubiquinone and other terpenoid-quinone biosynthesis, thiamine metabolism, tryptophan metabolism and cofactors biosynthesis, the phospholipase D signalling pathway and the phosphatidylinositol signalling system. Based on patient responses to five treatment options, we screened several metabolites using the Boruta algorithm and ranked their importance using the random forest algorithm. Lipids and their metabolism, including long-chain fatty acids, oxidized lipids, glycerophospholipids, phosphatidylcholine and phosphatidylethanolamine biosynthesis, helped differentiate drug treatment responses. In conclusion, this study revealed metabolic alterations associated with ITP in bone marrow supernatants and a potential biomarker predicting the response to ITP.

7.
Res Pract Thromb Haemost ; 8(1): 102318, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38433975

RESUMO

Background: Acquired hemophilia A (AHA) is a rare hemorrhagic disorder caused by factor (F)VIII inhibitors. The diagnosis and management of AHA remains challenging because of its rarity and heterogeneity. Objectives: To analyze the characteristics of AHA to enhance our understanding of this disease and identify effective treatment strategies. To analyze the characteristics of AHA to enhance our understanding of this disease and identify effective treatment strategies. Methods: Clinical features of 165 patients with AHA from a single center between July 1997 and December 2021 were retrospectively analyzed. Results: The median age of patients at diagnosis was 45 years. The median time to diagnosis was 30 days. All 165 patients experienced bleeding, with a median bleeding score (BS) of 4 (range, 2-12). Hemostatic therapy was administered to 129 (78.2%) patients. Bleeding control was achieved in 80.0% of patients who received prothrombin complex concentrate and in 92.3% of patients who were treated with recombinant activated FVII. Of the 163 patients who received immunosuppressive therapy, 80 (49.1%) received rituximab-based therapy with a 93.3% complete remission (CR) rate, 50 (30.7%) received steroids plus cyclophosphamide with an 85.0% CR rate, and 22 (13.5%) received steroids alone with an 82.4% CR rate. Six cases relapsed after a median duration of 330 days. Immunosuppressive therapy-related adverse events were reported in 17 patients. Seven deaths were recorded. FVIII inhibitor titer of ≥15 BU/mL and BS of ≥6 were identified as significantly poor prognostic factors for CR. Conclusion: Immunosuppressive therapies yield remarkably high response rates, with a CR rate exceeding 80%; notably, the regimen containing rituximab exhibits a CR rate of approximately 90%. FVIII inhibitor titer of ≥5 BU/mL and BS of ≥6 were poor predictors of CR in patients with AHA.

8.
Br J Haematol ; 204(4): 1207-1218, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37967471

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has a significant impact on the immune system. This is the first and largest study on pre-existing immune thrombocytopenia (ITP) patients infected with COVID-19 in China. We prospectively collected ITP patients infected with COVID-19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty-eight pre-existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty-seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25-2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO-RAs) (OR, 2.27; 95% CI, 1.60-3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09-3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12-5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63-7.64; p = 0.001), maintenance therapy including TPO-RAs (OR, 2.14; 95% CI, 1.17-3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17-7.91; p = 0.02). In this cohort study, we described the characteristics of pre-existing ITP patients infected with COVID-19 and identified several factors associated with poor outcomes.


Assuntos
COVID-19 , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Adulto , Púrpura Trombocitopênica Idiopática/epidemiologia , Púrpura Trombocitopênica Idiopática/terapia , Estudos de Coortes , Estudos Prospectivos , Trombocitopenia/epidemiologia , Trombocitopenia/etiologia , Trombopoetina , Proteínas Recombinantes de Fusão , Receptores Fc , Hidrazinas
9.
Am J Hematol ; 99(1): 28-37, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37851608

RESUMO

Acquired hemophilia A (AHA) is a rare but serious bleeding disorder. Randomized controlled trial (RCT) comparing the efficacy of immunosuppression therapy for AHA lacks. We conducted the first multicenter RCT aiming to establish whether the single-dose rituximab combination regimen was noninferior to the cyclophosphamide combination regimen. From 2017 to 2022, 63 patients with newly diagnosed AHA from five centers were randomly assigned 1:1 to receive glucocorticoid (methylprednisolone 0.8 mg/kg per day for the first 3 weeks and then tapered) plus single-dose rituximab (375 mg/m2 ; n = 31) or plus cyclophosphamide (2 mg/kg per day until inhibitor becomes negative, for a maximum of 5 weeks; n = 32). The primary outcome was complete remission (CR, defined as FVIII activity ≥50 IU/dL, FVIII inhibitor undetectable, immunosuppression tapered and no bleeding for 24 h without bypassing agents) rate measured within 8 weeks. The noninferiority margin was an absolute difference of 20%. Twenty-four (77.4%) patients in the rituximab group and 22 (68.8%) patients in the cyclophosphamide group achieved CR, which showed the noninferiority of the single-dose rituximab-based regimen (absolute difference = -8.67%, lower limit of the 95% confidence interval = -13.11%; Pnoninferiority = 0.005). No difference was found in the incidence of treatment-related adverse events. Single-dose rituximab plus glucocorticoid regimen showed similar efficacy and safety, without a reported risk of secondary malignancies or reproductive toxicity seen in cyclophosphamide, it might be recommended as a first-line therapy for AHA, especially in China where there is a young age trend in AHA patients. This trial was registered at ClinicalTrials.gov as #NCT03384277.


Assuntos
Glucocorticoides , Hemofilia A , Humanos , Ciclofosfamida/uso terapêutico , Glucocorticoides/uso terapêutico , Hemofilia A/tratamento farmacológico , Metilprednisolona/uso terapêutico , Rituximab/uso terapêutico , Resultado do Tratamento , Quimioterapia Combinada/efeitos adversos
11.
Expert Rev Hematol ; 16(12): 1125-1133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38009277

RESUMO

BACKGROUND: There is lacking studies of longitudinally assessment of fatigue and health-related quality of life (HRQoL) among Chinese immune thrombocytopenia (ITP) adults. We aimed to evaluate changes in fatigue and HRQoL and identify the associated factors. METHODS: Patients' characteristics, Functional Assessment of Chronic Illness Therapy (FACIT-F) and the ITP-specific Patient Assessment Questionnaire (ITP-PAQ) scores at admission (T0), at discharge (T1), and three months after discharge (T2) were collected. Linear mixed effects models were used to examine changes over time. RESULTS: We included 175 patients. The mean score of FACIT-F at T0 was 37.2 and increased at T1 (39.0), while then decreased at T2 (34.7). Patients who were single, retired, had persistent ITP, splenomegaly had more severe fatigue, whereas those who had not received any prior treatment and had a bleeding score of 0 at admission had milder fatigue. The mean score of ITP-PAQ was 57.7 at T0, then gradually increased to 60.3 at T1 and 62.8 at T2. Patients with persistent ITP and those who have never received treatment for ITP have better HRQoL. CONCLUSION: ITP adults' fatigue and HRQoL were impaired. Patients' fatigue improved at discharge but worsened at three months after discharge, while HRQoL gradually improved over time.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Adulto , Humanos , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/terapia , Qualidade de Vida , Fadiga/etiologia , Fadiga/terapia , China
12.
Res Pract Thromb Haemost ; 7(5): 100192, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37601010

RESUMO

Background: Multiple trials have confirmed that romiplostim could increase platelet count in individuals with primary immune thrombocytopenia (ITP), but no related study has assessed Chinese patients. Objectives: To assess the effectiveness of romiplostim as a second-line treatment of persistent or chronic ITP in Chinese adults. Methods: This phase III multicenter, randomized, placebo-controlled, double-blind, then open-label clinical trial (NCT02868099, CTR20150395) was conducted at 28 investigational sites in China. The patients were randomly assigned (3:1) to romiplostim (starting and maximum doses of 1 and 10 µg/kg, respectively) or placebo for 9 weeks (double-blind period), followed by the open-label period (both groups administered romiplostim) to week 22. The primary endpoint was the time (in weeks) during which platelet counts were ≥50 × 109/L in the double-blind period. Results: In this study, 202 patients (romiplostim, n = 151; placebo, n = 51) started the treatment. The median (range) numbers of weeks with platelet response after 6 weeks of treatment were 2 (0-6) and 0 (0-2) in patients administered romiplostim and placebo, respectively (P < .001). During the double-blind period, the proportions of patients with treatment-emergent adverse events were comparable between the romiplostim and placebo groups (82.8% vs 82.4%). The treatment-emergent adverse event with ≥10% difference in incidence between these 2 groups was injection site bleeding (1.3% vs 11.8%). Conclusion: Romiplostim significantly increased the time with maintained platelet response in patients with persistent or chronic ITP in comparison with placebo. No new safety signal was observed. Trial registration: ClinicalTrials.gov, NCT02868099. www.chinadrugtrials.org.cn/clinicaltrials.searchlist.dhtml, CTR20150395.

13.
Nat Commun ; 14(1): 4373, 2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474525

RESUMO

Mesenchymal stem cells (MSCs) possess potent immunomodulatory activity and have been extensively investigated for their therapeutic potential in treating inflammatory disorders. However, the mechanisms underlying the immunosuppressive function of MSCs are not fully understood, hindering the development of standardized MSC-based therapies for clinical use. In this study, we profile the single-cell transcriptomes of MSCs isolated from adipose tissue (AD), bone marrow (BM), placental chorionic membrane (PM), and umbilical cord (UC). Our results demonstrate that MSCs undergo a progressive aging process and that the cellular senescence state influences their immunosuppressive activity by downregulating PD-L1 expression. Through integrated analysis of single-cell transcriptomic and proteomic data, we identify GATA2 as a regulator of MSC senescence and PD-L1 expression. Overall, our findings highlight the roles of cell aging and PD-L1 expression in modulating the immunosuppressive efficacy of MSCs and implicating perinatal MSC therapy for clinical applications in inflammatory disorders.


Assuntos
Antígeno B7-H1 , Células-Tronco Mesenquimais , Humanos , Feminino , Gravidez , Regulação para Baixo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Multiômica , Proteômica , Placenta/metabolismo , Senescência Celular/genética , Células-Tronco Mesenquimais/metabolismo
14.
Ann Hematol ; 102(8): 2097-2107, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37354213

RESUMO

Approximately half of patients diagnosed with essential thrombocythemia (ET) are older adults (aged ≥ 60 years), but to date, little is known about the clinical and molecular characteristics of older patients diagnosed according to the 2016 World Health Organization criteria. We retrospectively collected clinical and molecular data from 282 older (≥ 60 years) and 621 younger ET patients (18-59 years) in China from March 1, 2012 to November 1, 2021 and summarized the clinical characteristics and treatment of these older ET patients. Compared to younger patients, older patients had a higher incidence of the JAK2V617F mutation (P = 0.001), a lower incidence of CALR mutations (P = 0.033) and a higher rate of epigenetic mutations (P < 0.001), TP53 mutations (P = 0.005), and RNA splicing mutations (P < 0.001). Older patients had not only a higher incidence of thrombosis but also a higher incidence of bleeding events. Furthermore, older patients had a significantly higher mortality rate after disease progression (P = 0.050) or after thrombotic events (P = 0.013). Risk factors for thrombosis or prognosis were significantly different between older patients and the entire ET cohort. In older patients, non-driver mutations contributed significantly to thrombotic complications and a poor prognosis, while the JAK2V617F mutation was a risk factor for overall survival but not for thrombotic events. The application of interferon in older ET patients was not inferior to that of hydroxyurea in terms of efficacy and safety. Older patients presented unique characteristics different from those of younger patients, which could provide new information for formulating more appropriate treatment and follow-up strategies.


Assuntos
Trombocitemia Essencial , Trombose , Humanos , Idoso , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/tratamento farmacológico , Trombocitemia Essencial/epidemiologia , Estudos Retrospectivos , Trombose/tratamento farmacológico , Hidroxiureia/uso terapêutico , Mutação , Janus Quinase 2/genética , Calreticulina/genética
16.
Glob Med Genet ; 10(2): 87-96, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37228869

RESUMO

Objective In this study, we aimed to evaluate the efficacy and safety of combination therapy, consisting of intravenous immunoglobulin (IVIg) and corticosteroids, in comparison to respective monotherapies in the treatment of relapsed immune thrombocytopenia (ITP) in adults. Methods A retrospective analysis of clinical data was conducted on 205 adult patients with relapsed ITP who received first-line combination therapy or monotherapy in multiple centers across China from January 2010 to December 2022. The study evaluated the patients' clinical characteristics, efficacy, and safety. Results We found that the proportion of patients with platelet counts in complete response was significantly higher in the combination group (71.83%) compared with the IVIg group (43.48%) and the corticosteroids group (23.08%). The mean PLT max in the combination group (178 × 10 9 /L) was significantly higher than that in the IVIg group (109 × 10 9 /L) and the corticosteroids group (76 × 10 9 /L). Additionally, the average time for platelet counts to reach 30 × 10 9 /L, 50 × 10 9 /L, and 100 × 10 9 /L in the combination group was significantly shorter than in the monotherapy groups. The proportion curves for reaching these platelet counts during treatment were also significantly different from those in the monotherapy groups. However, there were no significant differences in the effective rate, clinical characteristics, and adverse events among the three groups. Conclusion We concluded that combining IVIg and corticosteroids was a more effective and faster treatment for relapsed ITP in adults than using either therapy alone. The findings of this study provided clinical evidence and reference for the use of first-line combination therapy in the treatment of relapsed ITP in adults.

17.
J Thromb Thrombolysis ; 56(2): 291-300, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37249742

RESUMO

The current study involving 318 essential thrombocythemia (ET) patients with prior thrombosis was designed to identify risk factors that were predictive of recurrent thrombosis. The whole cohort was randomly split into derivation and validation cohorts. The random forest method, support vector machine with built-in recursive feature elimination model, and logistic multivariable analysis were performed in the derivation cohort, and cardiovascular risk factor (CVF) and RBC distribution width with standard deviation (RDW-SD) were finally selected as independent predictors. Subsequently we devise a 3-tiered model (low risk: 0 points; intermediate risk: 1-1.5 points; and high risk: 2.5 points) and it showed good discrimination in all cohorts. Moreover, the model was significantly correlated with rethrombosis-free survival (rTFS) (p = 0.0007 in the derivation cohort; p = 0.0019 in the validation cohort). In the whole cohort, cytoreductive therapy was more effective than antiplatelet agents alone for 10-year rTFS (p = 0.0336). No significant difference in 10-year rTFS was observed among interferon (IFN), hydroxyurea (HU), and IFN + HU therapy (p = 0.444). The present study helps identify individuals who need close monitoring and provides valuable risk signals for recurrence in ET patients with prior thrombosis.


Assuntos
Trombocitemia Essencial , Trombose , Humanos , Adulto , Trombocitemia Essencial/complicações , Trombocitemia Essencial/tratamento farmacológico , Trombose/etiologia , Hidroxiureia/uso terapêutico , Fatores de Risco , Inibidores da Agregação Plaquetária/uso terapêutico
18.
Res Pract Thromb Haemost ; 7(3): 100132, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37113987

RESUMO

Background: Thrombosis is an important cause of death in patients with polycythemia vera (PV). The conventional stratification of thrombosis may ignore some potential risk factors. Objectives: This study aimed to develop and validate a multiple factor-based prediction model of thrombosis for the 2016 World Health Organization-dened PV. Methods: Clinical and next-generation sequencing data from 2 cohorts of patients with PV were analyzed. Multivariable Cox regression analyses were conducted for the identification of thrombotic risk factors and model development. Results: The study involved 372 patients in the training cohort and another 195 patients in the external validation cohort. Multivariable analyses indicated that age ≥60 years (hazard ratio [HR] 2.56, 95% CI 1.51-4.35, P < .001), cardiovascular risk factors (HR 4.22, 95% CI 2.00-8.92, P < .001), at least 1 high-risk mutation for thrombosis (mutations in DNMT3A, ASXL1, or BCOR/BCORL1) (HR 4.35, 95% CI 2.62-7.21, P < .001), and previous thrombosis (HR 5.93, 95% CI 3.29-10.68, P < .001) were independent risk factors of thrombosis. After assigning coefficient-weighted scores to each risk factor mentioned above, a multiple factor-based prognostic score system of thrombosis (MFPS-PV) was developed, classifying patients into low-risk, intermediate-risk, and high-risk groups. Patients in the 3 groups had notably different thrombosis-free survival rates (P < .001). The MFPS-PV outperformed the conventional model in discrimination power (C-statistic: 0.87 [95% CI 0.83-0.91] vs 0.80 [95% CI 0.74-0.86]). The MFPS-PV was well calibrated and remained consistent during external validation. Conclusion: The MFPS-PV, integrating genetic and clinical characteristics for the first time, shows excellent accuracy and utility for thrombosis prediction in WHO-defined PV.

19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(2): 489-494, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37096524

RESUMO

OBJECTIVE: To screen better promoters and provide more powerful tools for basic research and gene therapy of hemophilia. METHODS: Bioinformatics methods were used to analyze the promoters expressing housekeeping genes with high abundance, so as to select potential candidate promoters. The GFP reporter gene vector was constructed, and the packaging efficiency of the novel promoter was investigated with EF1 α promoter as control, and the transcription and activities of the reporter gene were investigated too. The activity of the candidate promoter was investigated by loading F9 gene. RESULTS: The most potential RPS6 promoter was obtained by screening. There was no difference in lentiviral packaging between EF1 α-LV and RPS6-LV, and their virus titer were consistent. In 293T cells, the transduction efficiency and mean fluorescence intensity of RPS6pro-LV and EF1 αpro-LV were proportional to the lentiviral dose. The transfection efficiency of both promoters in different types of cells was in the following order: 293T>HEL>MSC; Compared with EF1 αpro-LV, RPS6pro-LV could obtain a higher fluorescence intensity in MSC cells, and RPS6pro-LV was more stable in long-term cultured HEL cells infected with two lentiviruses respectively. The results of RT-qPCR, Western blot and FIX activity (FIX∶C) detection of K562 cell culture supernatant showed that FIX expression in the EF1 α-F9 and RPS6-F9 groups was higher than that in the unloaded control group, and there was no significant difference in FIX expression between the EF1 α-F9 and RPS6-F9 groups. CONCLUSION: After screening and optimization, a promoter was obtained, which can be widely used for exogenous gene expression. The high stability and viability of the promoter were confirmed by long-term culture and active gene expression, which providing a powerful tool for basic research and clinical gene therapy of hemophilia.


Assuntos
Vetores Genéticos , Hemofilia A , Humanos , Transdução Genética , Hemofilia A/genética , Transfecção , Fatores de Coagulação Sanguínea/genética , Lentivirus/genética
20.
Thromb Res ; 226: 18-29, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37087805

RESUMO

INTRODUCTION: Platelet function, rather than platelet count, plays a crucial role in thrombosis in essential thrombocythemia (ET). However, little is known about the abnormal function of platelets in ET. Here, we investigated the functional characteristics of platelets in ET hemostasis to explore the causes of ET platelet dysfunction and new therapeutic strategies for ET. MATERIALS AND METHODS: We analyzed platelet aggregation, activation, apoptosis, and reactive oxygen species (ROS) in ET patients and JAK2V617F-positive ET-like mice. The effects of ROS on platelet function and the underlying mechanism were investigated by inhibiting ROS using N-acetylcysteine (NAC). RESULTS: Platelet aggregation, activation, apoptosis, ROS, and clot retraction were elevated in ET. No significant differences were observed between ET patients with JAK2V617F or CALR mutations. Increased ROS activated the JAK-STAT pathway, which may further influence platelet function. Inhibition of platelet ROS by NAC reduced platelet aggregation, activation, and apoptosis, and prolonged bleeding time. Furthermore, NAC treatment reduced platelet count in ET-like mice by inhibiting platelet production from megakaryocytes. CONCLUSIONS: Elevated ROS in ET platelets resulted in enhanced platelet activation, function and increased risk of thrombosis. NAC offers a potential therapeutic strategy for reducing platelet count.


Assuntos
Trombocitemia Essencial , Trombose , Camundongos , Animais , Trombocitemia Essencial/tratamento farmacológico , Trombocitemia Essencial/genética , Espécies Reativas de Oxigênio/metabolismo , Janus Quinases/metabolismo , Janus Quinases/farmacologia , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Fatores de Transcrição STAT/farmacologia , Plaquetas/metabolismo , Trombose/metabolismo , Acetilcisteína/metabolismo , Acetilcisteína/farmacologia
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