Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 254
Filtrar
1.
Nat Commun ; 15(1): 3371, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643278

RESUMO

Despite the high therapeutic response achieved with B-cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapy in relapsed and refractory multiple myeloma (R/R MM), primary resistance and relapse exist with single-target immunotherapy. Here, we design bispecific BC19 CAR T cells targeting BCMA/CD19 and evaluate antimyeloma activity in vitro and in vivo. Preclinical results indicate that BC19 CAR specifically recognize target antigens, and BC19 CAR T cells mediate selective killing of BCMA or CD19-positive cancer cells. BC19 CAR T cells also exhibit potent antigen-specific anti-tumor activity in xenograft mouse models. We conduct an open-label, single-arm, phase I/II study of BC19 CAR T cells in 50 patients with R/R MM (ChiCTR2000033567). The primary endpoint was safety. BC19 CAR T cells are well tolerated with grade 3 or higher cytokine release syndrome in 8% of patients and grade 1 neurotoxic events in 4% of patients, which meet the pre-specified primary endpoint. Secondary endpoints include overall response rate (92%), median progression-free survival (19.7 months), median overall survival (19.7 months) and median duration of response (not reached). Our study demonstrates that bispecific BC19 CAR T cells are feasible, safe and effective in treating patients with R/R MM.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Animais , Camundongos , Mieloma Múltiplo/patologia , Imunoterapia Adotiva/métodos , Antígeno de Maturação de Linfócitos B , Recidiva Local de Neoplasia , Antígenos CD19
2.
Cytotherapy ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38625072

RESUMO

BACKGROUND AIMS: Chimeric antigen receptor-T (CAR-T) cells have exhibited remarkable efficacy in treating refractory or relapsed multiple myeloma (R/R MM). Although obesity has a favorable value in enhancing the response to immunotherapy, less is known about its predictive value regarding the efficacy and prognosis of CAR-T cell immunotherapy. METHODS: We conducted a retrospective study of 111 patients with R/R MM who underwent CAR-T cell treatment. Using the body mass index (BMI) classification, the patients were divided into a normal-weight group (73/111) and an overweight group (38/111). We investigated the effect of BMI on CAR-T cell therapy outcomes in patients with R/R MM. RESULTS: The objective remission rates after CAR-T cell infusion were 94.7% and 89.0% in the overweight and normal-weight groups, respectively. The duration of response and overall survival were not significant difference between BMI groups. Compared to normal-weight patients, overweight patients had an improved median progression-free survival. There was no significant difference in cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome between the subgroups. In terms of hematological toxicity, the erythrocyte, hemoglobin, platelet, leukocyte and neutrophil recovery was accelerated in the overweight group. Fewer patients in the overweight group displayed moderate percent CD4 and CD4/CD8 ratios compared to the normal-weight group. Furthermore, the percent CD4 ratios were positively correlated with the levels of cytokines [interleukin-2 (IL-2) (day 14), interferon gamma (IFN-γ) (day 7) and tumor necrosis factor alpha (TNF-α) (days 14 and 21)] after cells infusion. On the other hand, BMI was positively associated with the levels of IFN-γ (day 7) and TNF-α (days 14 and 21) after CAR-T cells infusion. CONCLUSIONS: Overall, this study highlights the potential beneficial effect of a higher BMI on CAR-T cell therapy outcomes.

3.
Blood ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38603632

RESUMO

Notch signaling regulates cell-fate decisions in several developmental processes and cell functions. However, a role for Notch in hepatic thrombopoietin (TPO) production remains unclear. We noted thrombocytopenia in mice with hepatic Notch1 deficiency, and so investigated TPO production and other features of platelets in these mice. We found that the liver ultrastructure and hepatocyte function were comparable between control mice and Notch1-deficient mice. However, the Notch1-deficient mice had significantly lower plasma TPO and hepatic TPO mRNA levels, concomitant with lower numbers of platelets and impaired megakaryocyte differentiation and maturation, which were rescued by addition of exogenous TPO. Additionally, JAK2/STAT3 phosphorylation was significantly inhibited in Notch1-deficient hepatocytes, consistent with the RNA-seq analysis. JAK2/STAT3 phosphorylation and TPO production was also impaired in cultured Notch1-deficient hepatocytes after treatment with desialylated platelets. Consistently, hepatocyte-specific Notch1 deletion inhibited JAK2/STAT3 phosphorylation and hepatic TPO production induced by administration of desialylated platelets in vivo. Interestingly, Notch1 deficiency downregulated the expression of HES5 but not HES1. Moreover, desialylated platelets promoted the binding of HES5 to JAK2/STAT3, leading to JAK2/STAT3 phosphorylation and pathway activation in hepatocytes. Hepatocyte Ashwell-Morell receptor (AMR) (asialoglycoprotein receptor 1, ASGR1) physically associates with Notch1 and inhibition of AMR impaired Notch1 signaling activation and hepatic TPO production. Furthermore, blockage of Dll4 on desialylated platelets inhibited hepatocyte Notch1 activation and HES5 expression, JAK2/STAT3 phosphorylation and subsequent TPO production. In conclusion, our study identifies a novel regulatory role of Notch1 in hepatic TPO production, indicating that it might be a target for modulating TPO level.

4.
Ann Hematol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607553

RESUMO

NLRP6 plays a crucial role in maintaining intestinal homeostasis by regulating the interaction between the intestinal mucosa and the microbiota. However, the impact of NLRP6 deficiency on intestinal damage following hematopoietic stem cell transplantation (HSCT) remains poorly understood. In this study, we established a syngeneic HSCT mouse model using C57BL/6 mice as donors and NLRP6-/- or C57BL/6 mice as recipients. Our findings revealed that NLRP6 deficiency had minimal influence on peripheral blood cell counts and splenic immune cell proportions in transplanted mice. However, it exacerbated pathological changes in the small intestine on day 14 post-transplantation, accompanied by increased proportions of macrophages, dendritic cells, and neutrophils. Furthermore, the NLRP6 deficiency resulted in elevated expression of MPO and CD11b, while reducing the levels mature caspase-1 and mature IL-1ß in the intestine. Moreover, the NLRP6 deficiency disturbed the expression of apoptosis-related molecules and decreased the tight junction protein occludin. Notably, recipient mice with NLRP6 deficiency exhibited lower mRNA expression levels of antimicrobial genes, such as Reg3γ and Pla2g2a. The short-term increase in inflammatory cell infiltration caused by NLRP6 deficiency was associated with intestinal damage, increased apoptosis, reduced expression of antimicrobial peptides, and impaired intestinal repair. Taken together, our findings demonstrate that the loss of NLRP6 exacerbates post-transplantation intestinal damage in recipient mice.

5.
Int Immunopharmacol ; 130: 111760, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38428148

RESUMO

Bone marrow macrophages (Mφ) are essential components of the bone marrow niche that regulate the function of hematopoietic stem cells. Poor graft function and inhibition of hematopoietic production can result from abnormal macrophage function; however, the underlying mechanism is unclear. Clodronate liposomes (Clo-Lip) have been used widely to deplete macrophages and study their functions. Our previous results showed that Clod-Lip-mediated clearance of macrophages plays a vital role in regulating hematopoietic reconstruction after allogeneic hematopoietic cell transplantation (HCT). In this study, using an isogenic hematopoietic stem cell transplantation model, we found that Clod-Lip-mediated clearance of macrophages suppressed hematopoietic reconstruction by inhibiting the homing process of hematopoietic cells. We also demonstrated that macrophage depletion inhibited the direct supportive effect of macrophages on hematopoietic stem and progenitor cells and erythroid differentiation but promoted the production of megakaryocytic progenitors ex vivo. We showed that macrophages increase CD49e expression on hematopoietic stem and progenitor cells (HSPCs). However, CD49e inhibitors did not support the proliferative effect of macrophages on hematopoietic cells. In contrast, macrophage E-selectin/ intercellular cell adhesion molecule-1 (ICAM-1) may be involved in directly regulating HSPCs. In conclusion, macrophage depletion with Clo-Lip partially disrupts bone marrow hematopoiesis after HCT by impeding donor cell homing and macrophage-HSPCs interactions.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Integrina alfa5 , Integrina alfa5/metabolismo , Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/métodos , Hematopoese , Macrófagos/metabolismo
6.
Chemosphere ; 353: 141588, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430939

RESUMO

FeS2 is well-known for its role in redox reactions. However, the mechanism within heterogeneous electron-Fenton (Hetero-EF) systems remains unclear. In this study, a novel FeS2 based three-dimensional system (GF/Cu-FeS2) with self-generation of H2O2 was investigated for Hetero-EF degradation of sulfamethazine (SMZ). The results revealed that SMZ could be completely removed in 1.5 h, accompanying with the mineralization efficiency of 96% within 4 h. This system performed excellent stability, evidenced by consistently eliminated 100% of SMZ within 2 h over 4 cycles. The generated Reactive Oxygen Species (ROS) of •OH and •O2- in every degradation cycle were quantitatively measured to confirm the stability of the GF/Cu-FeS2 system. Additionally, the redox reaction mechanism on the surface of FeS2 was thoroughly analyzed in detail. The accelerated reduction of Fe(III) to Fe(II), triggered by S22- on the surface of FeS2, promoted the iron cycling, thereby quickening the Fenton process. Density Functional Theory (DFT) results illustrated the process of S22- to be oxidized to in detail. Therefore, this work provides deeper insight into the mechanistic role of S22- in FeS2 for environmental remediation.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Ferro , Enxofre , Sulfametazina , Compostos Ferrosos , Oxirredução
7.
Biochem Biophys Res Commun ; 703: 149686, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38367513

RESUMO

Transforming growth factor ß1 (TGFB1) refers to a pleiotropic cytokine exerting contrasting roles in hematopoietic stem cells (HSCs) functions in vitro and in vivo. However, the understanding of hematopoiesis in vivo, when TGFB1 is constantly deactivated, is still unclear, mainly due to significant embryonic lethality and the emergence of a fatal inflammatory condition, which makes doing these investigations challenging. Our study aims to find the specific role of TGFB1 in regulating hematopoiesis in vivo. We engineered mice strains (Vav1 or Mx1 promoter-driven TGFB1 knockout) with conditional knockout of TGFB1 to study its role in hematopoiesis in vivo. In fetal and adult hematopoiesis, TGFB1 KO mice displayed deficiency and decreased self-renewal capacity of HSCs with myeloid-biased differentiation. The results were different from the regulating role of TGFB1 in vitro. Additionally, our results showed that TGFB1 deficiency from fetal hematopoiesis stage caused more severe defect of HSCs than in the adult stage. Mechanistically, our findings identified TGFB1-SOX9-FOS/JUNB/TWIST1 signal axis as an essential regulating pathway in HSCs homeostasis. Our study may provide a scientific basis for clinical HSC transplantation and expansion.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas , Fator de Crescimento Transformador beta1 , Animais , Camundongos , Diferenciação Celular , Citocinas/metabolismo , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Fator de Crescimento Transformador beta1/metabolismo
8.
Cancer Cell Int ; 24(1): 66, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336746

RESUMO

Acute myeloid leukemia (AML) is a malignant hematologic disease caused by gene mutations and genomic rearrangements in hematologic progenitors. The PHF6 (PHD finger protein 6) gene is highly conserved and located on the X chromosome in humans and mice. We found that PHF6 was highly expressed in AML cells with MLL rearrangement and was related to the shortened survival time of AML patients. In our study, we knocked out the Phf6 gene at different disease stages in the AML mice model. Moreover, we knocked down PHF6 by shRNA in two AML cell lines and examined the cell growth, apoptosis, and cell cycle. We found that PHF6 deletion significantly inhibited the proliferation of leukemic cells and prolonged the survival time of AML mice. Interestingly, the deletion of PHF6 at a later stage of the disease displayed a better anti-leukemia effect. The expressions of genes related to cell differentiation were increased, while genes that inhibit cell differentiation were decreased with PHF6 knockout. It is very important to analyze the maintenance role of PHF6 in AML, which is different from its tumor-suppressing function in T-cell acute lymphoblastic leukemia (T-ALL). Our study showed that inhibiting PHF6 expression may be a potential therapeutic strategy targeting AML patients.

9.
Cell Death Dis ; 15(2): 159, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383474

RESUMO

Bone marrow ablation is routinely performed before hematopoietic stem cell transplantation (HSCT). Hematopoietic stem and progenitor cells (HSPCs) require a stable bone marrow microenvironment to expand and refill the peripheral blood cell pool after ablation. Roundabout guidance receptor 4 (Robo4) is a transmembrane protein exclusive to endothelial cells and is vital in preserving vascular integrity. Hence, the hypothesis is that Robo4 maintains the integrity of bone marrow endothelial cells following radiotherapy. We created an endothelial cell injury model with γ-radiation before Robo4 gene manipulation using lentiviral-mediated RNAi and gene overexpression techniques. We demonstrate that Robo4 and specific mesenchymal proteins (Fibronectin, Vimentin, αSma, and S100A4) are upregulated in endothelial cells exposed to irradiation (IR). We found that Robo4 depletion increases the expression of endoglin (CD105), an auxiliary receptor for the transforming growth factor (TGF-ß) family of proteins, and promotes endothelial-to-mesenchymal transition (End-MT) through activation of both the canonical (Smad) and non-canonical (AKT/NF-κB) signaling pathways to facilitate Snail1 activation and its nuclear translocation. Endothelial Robo4 overexpression stimulates the expression of immunoglobulin-like adhesion molecules (ICAM-1 and VCAM-1) and alleviates irradiation-induced End-MT. Our coculture model showed that transcriptional downregulation of endothelial Robo4 reduces HSPC proliferation and increases HSC quiescence and apoptosis. However, Robo4 overexpression mitigated the damaged endothelium's suppressive effects on HSC proliferation and differentiation. These findings indicate that by controlling End-MT, Robo4 preserves microvascular integrity after radiation preconditioning, protects endothelial function, and lessens the inhibitory effect of damaged endothelium on hematopoietic reconstitution.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Receptores de Superfície Celular , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Células Endoteliais/metabolismo , Endotélio , Células-Tronco Hematopoéticas/metabolismo
10.
Biochem Biophys Res Commun ; 693: 149366, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38091842

RESUMO

INTRODUCTION: Celastrol is an active pentacyclic triterpenoid extracted from Tripterygium wilfordii and has anti-inflammatory and anti-tumor properties. Whether Celastrol modulates platelet function remains unknown. Our study investigated its role in platelet function and thrombosis. METHODS: Human platelets were isolated and incubated with Celastrol (0, 1, 3 and 5 µM) at 37 °C for 1 h to measure platelet aggregation, granules release, spreading, thrombin-induced clot retraction and intracellular calcium mobilization. Additionally, Celastrol (2 mg/kg) was intraperitoneally administrated into mice to evaluate hemostasis and thrombosis in vivo. RESULTS: Celastrol treatment significantly decreased platelet aggregation and secretion of dense or alpha granules induced by collagen-related peptide (CRP) or thrombin in a dose-dependent manner. Additionally, Celastrol-treated platelets showed a dramatically reduced spreading activity and decreased clot retraction. Moreover, Celastrol administration prolonged tail bleeding time and inhibited formation of arterial/venous thrombosis. Furthermore, Celastrol significantly reduced calcium mobilization. CONCLUSION: Celastrol inhibits platelet function and venous/arterial thrombosis, implying that it might be utilized for treating thrombotic diseases.


Assuntos
Ativação Plaquetária , Trombose , Humanos , Animais , Camundongos , Cálcio/metabolismo , Trombina/metabolismo , Hemostasia , Agregação Plaquetária , Plaquetas/metabolismo , Triterpenos Pentacíclicos , Trombose/metabolismo
11.
Thromb Haemost ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38151026

RESUMO

BACKGROUND: Transforming growth factor-ß1 (TGF-ß1) modulates multiple cellular functions during development and tissue homeostasis. A large amount of TGF-ß1 is stored in platelet α-granules and released upon platelet activation. Whether platelet-derived TGF-ß1 plays a role in venous thrombosis remains unclear. This study intends to assess the role of platelet-derived TGF-ß1 in the development of venous thrombosis in mice. MATERIAL AND METHODS: TGF-ß1flox/flox and platelet-specific TGF-ß1-/- mice were utilized to assess platelet function in vitro, arterial thrombosis induced by FeCl3, tail bleeding time, prothrombin time (PT), activated partial thromboplastin time (APTT), and deep vein thrombosis induced through ligation of the inferior vena cava (IVC). The IVC sample was collected to measure accumulation of neutrophils, monocytes, and the formation of neutrophil extracellular traps (NETs) by immunofluorescence staining. RESULTS: TGF-ß1 deficiency in platelets did not affect the number of circulating platelets, platelet aggregation, adenosine triphosphate release, and integrin αIIbß3 activation. Meanwhile, TGF-ß1 deficiency did not alter the arterial thrombus formation, hemostasis, and coagulation time (PT and APTT), but significantly impaired venous thrombus formation, inhibited the recruitment and accumulation of neutrophils and monocytes in thrombi, as well as reduced formation of NETs and platelet-neutrophil complex. In addition, adoptive transfer of TGF-ß1flox/flox platelets to TGF-ß1-/- mice rescued the impaired venous thrombus formation, recruitment of leukocytes and monocytes, as well as the NETs formation. CONCLUSION: In conclusion, platelet-derived TGF-ß1 positively modulates venous thrombus formation in mice, indicating that targeting TGF-ß1 might be a novel approach for treating venous thrombosis without increasing the risk of bleeding.

12.
Clin Exp Med ; 23(8): 5241-5254, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37907623

RESUMO

Chimeric antigen receptor T (CAR-T) cell therapy exhibits remarkable efficacy against refractory or relapsed multiple myeloma (RRMM); however, the immune deficiency following CAR-Ts infusion has not been well studied. In this study, 126 patients who achieved remission post-CAR-Ts infusion were evaluated for cellular immunity. Following lymphodepletion (LD) chemotherapy, the absolute lymphocyte count (ALC) and absolute counts of lymphocyte subsets were significantly lower than baseline at D0. Grade ≥ 3 lymphopenia occurred in 99% of patients within the first 30 days, with most being resolved by 180 days. The median CD4+ T-cell count was consistently below baseline and the lower limit of normal (LLN) levels at follow-up. Conversely, the median CD8+ T-cell count returned to the baseline and LLN levels by D30. The median B-cell count remained lower than baseline level at D60 and returned to baseline and LLN levels at D180. In the first 30 days, 27 (21.4%) patients had 29 infections, with the majority being mild to moderate in severity (21/29; 72.4%). After day 30, 44 (34.9%) patients had 56 infections, including 20 severe infections. One patient died from bacteremia at 3.8 months post-CAR-Ts infusion. In conclusion, most patients with RRMM experienced cellular immune deficiency caused by LD chemotherapy and CAR-Ts infusion. The ALC and most lymphocyte subsets gradually recovered after day 30 of CAR-Ts infusion, except for CD4+ T cells. Some patients experience prolonged CD4+ T-cell immunosuppression without severe infection.


Assuntos
Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Humanos , Mieloma Múltiplo/tratamento farmacológico , Imunoterapia Adotiva/efeitos adversos , Imunidade Celular , Terapia Baseada em Transplante de Células e Tecidos
13.
Regen Ther ; 24: 54-63, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37868719

RESUMO

Introduction: Clodronate-Liposomes (Clod-Lipo) injection after hematopoietic stem cell transplantation (HSCT) has been shown to be detrimental to hematopoietic reconstitution after transplantation, and our previous study showed that Clod-Lipo injection after HSCT increased adipocytes in the bone marrow cavity of mice after HSCT, but the reason for the large increase in adipocytes has not been clearly explained. The aim of this study was to investigate the source and mechanism of bone marrow cavity adipocytes after HSCT injection of Clod-Lipo. Methods: BALB/c mice received 7.5 Gy of total body irradiation followed by infusion of 5x106 bone marrow mononuclear cells from C57BL/6 via the tail vein. Clod-Lipo were injected through the tail vein on the first day after HSCT and every 5 days for the rest of the day. BALB/c mice were then divided into three groups: BMT, BMT + Clodronate-Liposomes (BMT + Clod-Lipo), and BMT + PBS-Liposomes (BMT + PBS-Lipo). Bone marrow pathological changes were detected by H&E staining, Western blot was used to detect the expression of NLRP3 and Caspase-1 in mouse bone marrow cells, and RT-qPCR was used to detect the expression levels of the key transcription factors peroxisome proliferator-activated receptor γ (PPAR-γ) and CCAAT/enhancer binding protein (C/EBPα) mRNA in bone marrow cells. Mouse mesenchymal stem cells (MSC) cultured in vitro were identified by flow cytometry, and adipocyte induction assays were performed using Clod-Lipo action for 24 h, Oil red staining was used to identify adipogenesis. Western blot was performed to detect NLRP3 and caspase-1 expression in MSC after Clod-Lipo action. Caspase-1 was blocked with Ac-YVAD-cmk (Ac-YV), followed by adipogenesis assay after 24 h of Clod-Lipo action to observe the change in the amount of adipogenesis. Results: Compared with the other two groups, a significant increase in adipocytes was found in the Clod-Lipo group by HE staining, and increased expression of NLRP3 and Caspase-1 in mouse bone marrow cells was found by western Blot. By culturing MSC in vitro and performing adipogenesis assay after 24 h of Clod-Lipo action, it was found that adipogenesis was increased in the Clod-Lipo group, while the expression of NLRP3 and Caspase-1 was increased in MSCs, and adipogenesis assay was performed after 2 h of action using Caspase-1 inhibitor, and it was found that adipocytes was reduced. Conclusions: The results of this study suggest that MSC are biased towards adipocyte generation in response to Clod-Lipo, a process that may be associated with activation of the NLRP3/caspase-1 pathway.

14.
Int Immunopharmacol ; 125(Pt A): 111091, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37883814

RESUMO

The MPLW515L mutation is a prevalent genetic mutation in patients with myeloproliferative neoplasms (MPN), and utilizing this mutation in mice model can provide important insights into the disease. However, the relationship between intestinal homeostasis and MPN mice model remains elusive. In this study, we utilized a retroviral vector to transfect hematopoietic stem cells with the MPLW515L mutation, creating mutated MPN mice model to investigate their intestinal status. Our results revealed that the MPLW515L in MPN mice model aggravated inflammation in the intestines, decreased the levels of tight junction proteins and receptors for bacteria metabolites. Additionally, there was increased activation of the caspase1/IL-1ß signaling pathway and a significant reduction in phos-p38 levels in the intestinal tissue in MPN mice. The MPLW515L mutation also led to up-expression of anti-microbial genes in the intestinal tract. Though the mutation had no impact on the alpha diversity and dominant bacterial taxa, it did influence the rare bacterial taxa/sub-communities and consequently impacted intestinal homeostasis. Our findings demonstrate the significance of MPLW515L mice model for studying MPN disease and highlight the mutation's influence on intestinal homeostasis, including inflammation, activation of the IL-1ß signaling pathway, and the composition of gut microbial communities.


Assuntos
Transtornos Mieloproliferativos , Neoplasias , Humanos , Animais , Camundongos , Mutação , Transdução de Sinais , Modelos Animais de Doenças , Janus Quinase 2/metabolismo , Inflamação , Calreticulina/genética , Calreticulina/metabolismo , Receptores de Trombopoetina
15.
Artigo em Inglês | MEDLINE | ID: mdl-37768178

RESUMO

A novel Gram-stain-negative, facultatively anaerobic and heterotrophic bacterium, designated strain ZH257T, was isolated from in situ enrichment samples incubated on the seamount floor of the Western Pacific Ocean. Cells were rod-shaped, oxidase- and catalase- positive, and motile by means of polar flagella. Strain ZH257T grew at 4-37 °C (optimum, 28-32 °C), pH 6.0-9.0 (optimum, pH 7.0) and with 2.0-9.0 % (w/v) NaCl (optimum, 3.0-4.0 %). Strain ZH257T was most closely related to members of the genus Pseudophaeobacter, sharing 99.13, 98.27 and 96.89 % 16S rRNA gene sequence identities with Pseudophaeobacter flagellatus GDMCC 1.2988T, Pseudophaeobacter arcticus DSM 23566T and Pseudophaeobacter leonis DSM 25627T, respectively. The DNA G+C content was 59.2 mol%. The estimated average nucleotide identity and digital DNA-DNA hybridization values between strain ZH257T and its closely related species were 79.61-93.04 % and 23.10-50.20 %, respectively. Strain ZH257T harboured complete denitrification and nitrate assimilation pathways. Strain ZH257T contained summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) as major fatty acids (>5 %), and Q-10 as the major respiratory quinone. The polar lipid profile contained phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, an unidentified phospholipid, an unidentified aminolipid and four unidentified lipids. The combined phenotypic, genotypic and chemotaxonomic data showed that strain ZH257T represents a novel species of the genus Pseudophaeobacter, for which the name Pseudophaeobacter profundi sp. nov. is proposed, with the type strain ZH257T (=MCCC M29024T=KACC 23147T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Oceano Pacífico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Filogenia , Fosfolipídeos/química
16.
Pest Manag Sci ; 79(12): 5304-5311, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37605962

RESUMO

BACKGROUND: Khapra beetle (Trogoderma granarium Everts), one of the most important quarantine pests globally, is capable of causing severe infestation and huge economic loss to stored grain, and its interception rate has increased in major global trade countries over the past few years. However, difficulties remain in distinguishing this species with similar ones. In order to assist border ports and warehouses in khapra beetle's effective rapid identification as well as pest control at the early stages of monitoring or interception, we herein developed a new and rapid visual detection assay for T. granarium based on recombinase polymerase amplification (RPA) and the CRISPR/Cas12a system. RESULTS: We designed and selected the first khapra beetle-specific RPA primers and crRNA, and optimized the visualization reaction system (Cas12a/CrRNA = 100 nM/500 nM). With only a 37 °C-heat-source and a blue light torch, RPA and CRISPR/CAS12a-based visualization assays can be completed within 40 min to differentiate between khapra beetle and nine similar Dermestidae species. After DNA extraction using a kit (4-5 h) or a simple method (5 min), the specific amplicons were obtained after a 15 min RPA reaction at 37 °C, followed by a 15 min color reaction under 37 °C in dark conditions using a CRISPR/CAS12a system and a fluorescent probe (5'-FAM/3'-BHQ1 labeled). This method is ingenious to low levels of DNA (10-1 ng µL-1 ) and meets the sensitivity requirements for detecting a single khapra beetle's egg (≈0.7 mm). CONCLUSION: Our specificity and sensitivity analysis inferred that the present visualization system is effective to quickly and uniquely detect khapra beetle at room temperature (37 °C), thereby preventing this species before they spread widely. Our study is suitable for being pushed forward in storage pest management, and provides value as a reference for monitoring and identification of other pests. © 2023 Society of Chemical Industry.


Assuntos
Sistemas CRISPR-Cas , Besouros , Animais , Recombinases , Besouros/genética , DNA
17.
Nat Commun ; 14(1): 4829, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563135

RESUMO

Human MutT Homolog 1 (MTH1) is a nucleotide pool sanitization enzyme that hydrolyzes oxidized nucleotides to prevent their mis-incorporation into DNA under oxidative stress. Expression and functional roles of MTH1 in platelets are not known. Here, we show MTH1 expression in platelets and its deficiency impairs hemostasis and arterial/venous thrombosis in vivo. MTH1 deficiency reduced platelet aggregation, phosphatidylserine exposure and calcium mobilization induced by thrombin but not by collagen-related peptide (CRP) along with decreased mitochondrial ATP production. Thrombin but not CRP induced Ca2+-dependent mitochondria reactive oxygen species generation. Mechanistically, MTH1 deficiency caused mitochondrial DNA oxidative damage and reduced the expression of cytochrome c oxidase 1. Furthermore, MTH1 exerts a similar role in human platelet function. Our study suggests that MTH1 exerts a protective function against oxidative stress in platelets and indicates that MTH1 could be a potential therapeutic target for the prevention of thrombotic diseases.


Assuntos
Plaquetas , Trombose , Humanos , Plaquetas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Trombina/farmacologia , Trombina/metabolismo , Estresse Oxidativo , Hemostasia , Nucleotídeos/metabolismo , Mitocôndrias/metabolismo , Trombose/genética , Trombose/prevenção & controle , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo
18.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37511237

RESUMO

Herein, we report the synthesis of bimetal-organic frameworks (BMOFs) with both Brønsted and Lewis acidities, in which phosphotungstic acid (PTA) was encapsulated in BMOFs. It is efficient in converting starch to 5-hydroxymethyl-furfural (HMF) in deep eutectic solvents (DESs) such as choline chloride and formic acid. The highest yield of HMF (37.94%) was obtained using P0.5/BMOFs1.0 to catalyze starch in a mixed solvent system comprising DESs and ethyl acetate (EAC) (v/v; 2:3) at 180 °C and a reaction time of 10 min. Employing a DES as a cocatalyst and solvent reduced the use of organic solvents. The catalyst showed adequate reusability, and the HMF yield only decreased by 2.88% after six cycles of reuse compared with that of the initial catalyst. This study demonstrates the application potential of BMOFs in the conversion of biomass to useful molecules with commercial and/or research value.


Assuntos
Solventes Eutéticos Profundos , Furaldeído , Ácido Fosfotúngstico , Carboidratos , Solventes , Hexoses , Amido , Catálise
19.
Transplant Cell Ther ; 29(8): 492.e1-492.e10, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37192732

RESUMO

Hepatic sinusoidal obstruction syndrome (HSOS) is a life-threatening complication that may occur after hematopoietic stem cell transplantation (HSCT). Hepatic sinusoidal endothelial cell (HSEC) injury and liver fibrosis are key mechanisms of HSOS. Thymosin ß4 (Tß4) is an active polypeptide that functions in a variety of pathologic and physiologic states, including inflammation regulation, anti-apoptosis, and anti-fibrosis. In this study, we found that Tß4 can stimulate HSEC proliferation, migration, and tube formation in vitro via activation of pro-survival signaling AKT (protein kinase B). In addition, Tß4 resisted γ irradiation-induced HSEC growth arrest and apoptosis in parallel with upregulation of anti-apoptotic protein B cell lymphoma extra-large (Bcl-xL) and B cell lymphoma-2 (Bcl-2), which may be associated with activation of AKT. More importantly, Tß4 significantly inhibited irradiation-induced pro-inflammatory cytokines in parallel with negative regulation of TLR4/MyD88/NF-κB and MAPK p38. Meanwhile, Tß4 reduced intracellular reactive oxygen species production and upregulated antioxidants in HSECs. Additionally, Tß4 inhibited irradiation-induced activation of hepatic stellate cells by downregulating the expression of fibrogenic markers α-SMA, PAI-1, and TGF-ß. In a murine HSOS model, levels of circulating alanine aminotransferase, aspartate aminotransferase, total bilirubin, and pro-inflammatory cytokines IL-6, IL-1ß, and TNF-α were significantly reduced after administration of Tß4 peptide; furthermore, Tß4 treatment successfully ameliorated HSEC injury, inflammatory damage, and fibrosis of the murine liver. Taken together, our findings indicate that Tß4 stimulates proliferation and angiogenesis of HSECs, exerts a cytoprotective effect, and attenuates liver injury in a murine HSOS model, suggesting that its use may be a potential strategy to prevent and treat HSOS after HSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Hepatopatia Veno-Oclusiva , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Hepatopatia Veno-Oclusiva/tratamento farmacológico , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/prevenção & controle , Fibrose , Fator de Crescimento Transformador beta , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
20.
Int Immunopharmacol ; 120: 110381, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37245302

RESUMO

BACKGROUND: Dimethyl fumarate (DMF) is a methyl ester of fumaric acid and has been approved for treating multiple sclerosis (MS) and psoriasis due to anti-inflammatory effect. There is a close association between platelets and the pathogenesis of MS. Whether DMF affects platelet function remains unclear. Our study intends to evaluate DMF's effect on platelet function. METHODS: Washed human platelets were treated with different concentrations of DMF (0, 50, 100 and 200 µM) at 37 °C for 1 h followed by analysis of platelet aggregation, granules release, receptors expression, spreading and clot retraction. In addition, mice received intraperitoneal injection of DMF (15 mg/kg) to assess tail bleeding time, arterial and venous thrombosis. RESULTS: DMF significantly inhibited platelet aggregation and the release of dense/alpha granules in response to collagen-related peptide (CRP) or thrombin stimulation dose-dependently without altering the expression of platelet receptors αIIbß3, GPIbα, and GPVI. In addition, DMF-treated platelets presented significantly reduced spreading on collagen or fibrinogen and thrombin-mediated clot retraction along with the decreased phosphorylation of c-Src and PLCγ2. Moreover, administration of DMF into mice significantly prolonged the tail bleeding time and impaired arterial and venous thrombus formation. Furthermore, DMF reduced the generation of intracellular reactive oxygen species and calcium mobilization, and inhibited NF-κB activation and the phosphorylation of ERK1/2, p38 and AKT. CONCLUSION: DMF inhibits platelet function and arterial/venous thrombus formation. Considering the presence of thrombotic events in MS, our study indicates that DMF treatment for patients with MS might obtain both anti-inflammatory and anti-thrombotic benefits.


Assuntos
Ativação Plaquetária , Trombose , Humanos , Camundongos , Animais , Fibrinolíticos , Fumarato de Dimetilo/farmacologia , Fumarato de Dimetilo/uso terapêutico , Fumarato de Dimetilo/metabolismo , Trombina/metabolismo , Trombina/farmacologia , Agregação Plaquetária , Plaquetas/metabolismo , Trombose/tratamento farmacológico , Trombose/etiologia , Trombose/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...