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1.
Chemosphere ; 361: 142525, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838867

RESUMO

Pseudomonas sp. ZHL02, removing nitrogen via ammonia nitrogen (NH4+) → hydroxylamine (HN2OH) → nitrite (NO2-) → nitrate (NO3-) → NO2- → nitric oxide (NO) → nitrous oxide (N2O) pathway was employed for getting in-depth information on the heterotrophic nitrification-aerobic denitrification (HNAD) pathway from carbon oxidation, nitrogen conversion, electron transport process, enzyme activity, as well as gene expression while sodium succinate, sodium citrate, and sodium acetate were utilized as the carbon sources. The nitrogen balance analysis results demonstrated that ZHL02 mainly removed NH4+-N through assimilation. The carbon source metabolism resulted in the discrepancies in electron transport chain and nitrogen removal between different HNAD bacteria. Moreover, the prokaryotic strand-specific transcriptome method showed that, amo and hao were absent in ZHL02, and unknown genes may be involved in ZHL02 during the HNAD process. As a fascinating process for removing nitrogen, the HNAD process is still puzzling, and the relationship between carbon metabolism and nitrogen metabolism among different HNAD pathways should be studied further.


Assuntos
Carbono , Desnitrificação , Processos Heterotróficos , Nitrificação , Nitrogênio , Carbono/metabolismo , Nitrogênio/metabolismo , Pseudomonas/metabolismo , Aerobiose , Nitritos/metabolismo , Nitratos/metabolismo
2.
Cell Rep ; 43(6): 114301, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38823016

RESUMO

CD8+ T cells are rendered exhausted in tumor and chronic infection. Among heterogeneous exhausted T cells, a subpopulation of progenitor-like (Tpex) cells have been found important for long-term tumor or pathogen control and are also the main responders in immunotherapy. Using an RFP reporter mouse for the orphan nuclear receptor NR4A1, originally characterized as critical in T cell dysfunction, we discover that the reporter is highly expressed in Tpex cells in tumor and chronic infection. Enforced expression of Nr4a1 promotes Tpex cell accumulation, whereas tumor control is improved after Nr4a1 deletion, associated with increased effector function but decreased long-term maintenance of CD8+ T cells. Integrating chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) analysis, NR4A1 is found to bind and promote the expression of Tpex-related genes, as well as suppress terminal differentiation-associated genes. This study therefore has identified a key role of NR4A1 in Tpex regulation and provides a promising target for immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Diferenciação Celular , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Microambiente Tumoral , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Camundongos , Microambiente Tumoral/imunologia , Camundongos Endogâmicos C57BL , Transcrição Gênica , Células-Tronco/metabolismo , Humanos
3.
Eur J Med Res ; 29(1): 310, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38840262

RESUMO

KDM6A (lysine demethylase 6A) has been reported to undergo inactivating mutations in colorectal cancer, but its function in the progression of colorectal cancer has not been evaluated using animal models of colorectal cancer. In this study, we found that knocking out KDM6A expression in mouse intestinal epithelium increased the length of villus and crypt, promoting the development of AOM (azoxymethane)/DSS (dextran sulfate sodium salt)-induced colorectal cancer. On the other hand, knocking down KDM6A expression promoted the growth of colorectal cancer cells. In molecular mechanism studies, we found that KDM6A interacts with HIF-1α; knocking down KDM6A promotes the binding of HIF-1α to the LDHA promoter, thereby promoting LDHA expression and lactate production, enhancing glycolysis. Knocking down LDHA reversed the malignant phenotype caused by KDM6A expression loss. In summary, this study using animal models revealed that KDM6A loss promotes the progression of colorectal cancer through reprogramming the metabolism of the colorectal cancer cells, suggesting that restoring the function of KDM6A is likely to be one of the strategies for colorectal cancer treatment.


Assuntos
Neoplasias Colorretais , Progressão da Doença , Glicólise , Histona Desmetilases , Animais , Humanos , Camundongos , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética
4.
Front Immunol ; 15: 1391504, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887292

RESUMO

Diabetes is a prevalent chronic disease that traditionally requires severe reliance on medication for treatment. Oral medication and exogenous insulin can only temporarily maintain blood glucose levels and do not cure the disease. Most patients need life-long injections of exogenous insulin. In recent years, advances in islet transplantation have significantly advanced the treatment of diabetes, allowing patients to discontinue exogenous insulin and avoid complications.Long-term follow-up results from recent reports on islet transplantation suggest that they provide significant therapeutic benefit although patients still require immunotherapy, suggesting the importance of future transplantation strategies. Although organ shortage remains the primary obstacle for the development of islet transplantation, new sources of islet cells, such as stem cells and porcine islet cells, have been proposed, and are gradually being incorporated into clinical research. Further research on new transplantation sites, such as the subcutaneous space and mesenteric fat, may eventually replace the traditional portal vein intra-islet cell infusion. Additionally, the immunological rejection reaction in islet transplantation will be resolved through the combined application of immunosuppressant agents, islet encapsulation technology, and the most promising mesenchymal stem cells/regulatory T cell and islet cell combined transplantation cell therapy. This review summarizes the progress achieved in islet transplantation, and discusses the research progress and potential solutions to the challenges faced.


Assuntos
Transplante das Ilhotas Pancreáticas , Transplante das Ilhotas Pancreáticas/métodos , Humanos , Animais , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/imunologia
5.
BMC Plant Biol ; 24(1): 376, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38714947

RESUMO

BACKGROUND: Casuarina equisetifolia (C. equisetifolia) is a woody species with many excellent features. It has natural resistance against drought, salt and saline-alkali stresses. WRKY transcription factors (TFs) play significant roles in plant response to abiotic stresses, therefore, molecular characterization of WRKY gene family under abiotic stresses holds great significance for improvement of forest trees through molecular biological tools. At present, WRKY TFs from C. equisetifolia have not been thoroughly studied with respect to their role in salt and saline-alkali stresses response. The current study was conducted to bridge the same knowledge gap. RESULTS: A total of 64 WRKYs were identified in C. equisetifolia and divided into three major groups i.e. group I, II and III, consisting of 10, 42 and 12 WRKY members, respectively. The WRKY members in group II were further divided into 5 subgroups according to their homology with Arabidopsis counterparts. WRKYs belonging to the same group exhibited higher similarities in gene structure and the presence of conserved motifs. Promoter analysis data showed the presence of various response elements, especially those related to hormone signaling and abiotic stresses, such as ABRE (ABA), TGACG (MeJA), W-box ((C/T) TGAC (T/C)) and TC-rich motif. Tissue specific expression data showed that CeqWRKYs were mainly expressed in root under normal growth conditions. Furthermore, most of the CeqWRKYs were up-regulated by NaCl and NaHCO3 stresses with few of WRKYs showing early responsiveness to both stresses while few others exhibiting late response. Although the expressions of CeqWRKYs were also induced by cold stress, the response was delayed compared with other stresses. Transgenic C. equisetifolia plants overexpressing CeqWRKY11 displayed lower electrolyte leakage, higher chlorophyll content, and enhanced tolerance to both stresses. The higher expression of abiotic stress related genes, especially CeqHKT1 and CeqPOD7, in overexpression lines points to the maintenance of optimum Na+/K+ ratio, and ROS scavenging as possible key molecular mechanisms underlying salt stress tolerance. CONCLUSIONS: Our results show that CeqWRKYs might be key regulators of NaCl and NaHCO3 stresses response in C. equisetifolia. In addition, positive correlation of CeqWRKY11 expression with increased stress tolerance in C. equisetifolia encourages further research on other WRKY family members through functional genomic tools. The best candidates could be incorporated in other woody plant species for improving stress tolerance.


Assuntos
Proteínas de Plantas , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Cloreto de Sódio/farmacologia , Filogenia , Bicarbonato de Sódio/farmacologia , Estresse Salino/genética , Estresse Fisiológico/genética , Genoma de Planta
6.
Micromachines (Basel) ; 15(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675338

RESUMO

The single-event effects (SEEs) of frequency divider circuits and the radiation tolerance of the hardened circuit are studied in this paper. Based on the experimental results of SEEs in InP HBTs, a transient current model for sensitive transistors is established, taking into account the influence of factors such as laser energy, base-collector junction voltage, and radiation position. Moreover, the SEEs of the (2:1) static frequency divider circuit with the InP DHBT process are simulated under different laser energies by adding the transient current model at sensitive nodes. The effect of the time relationship between the pulsed laser and clock signal are discussed. Changes in differential output voltage and the degradation mechanism of unhardened circuits are analyzed, which are mainly attributed to the cross-coupling effect between the transistors in the differential pair. Furthermore, the inverted output is directly connected to the input, leading to a feedback loop and causing significant logic upsets. Finally, an effective hardened method is proposed to provide redundancy and mitigate the impacts of SEEs on the divider. The simulation results demonstrate a notable improvement in the radiation tolerance of the divider.

7.
J Cardiothorac Surg ; 19(1): 151, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521937

RESUMO

BACKGROUND: Iatrogenic complications of endovascular treatment for central venous stenosis have not yet been reported. Here we present a case of a patient on maintenance hemodialysis who developed catheter-related superior vena cava syndrome and subsequently suffered from hemorrhagic pericardial tamponade after undergoing percutaneous transluminal angioplasty and stenting. CASE PRESENTATION: A 72-year-old male patient presented with uremia, and had been receiving maintenance hemodialysis for the past five years. The patient initially presented with dysfunction of the dialysis catheter (a cuffed tunneled double-lumen catheter in the right internal jugular vein). Imaging examination revealed a segmental occlusion of the superior vena cava stretching from the distal end of the dialysis catheter up to right atrium entrance, apparent compensatory dilatation of the azygos vein, and abundant subcutaneous collaterals. The patient underwent percutaneous transluminal balloon dilatation and stenting (covered stent) of the superior vena cava in the Cath Lab. During the procedure, with forceful advancement of the guidewire, it was observed to progress for a distance before a "smoke" appeared, and an outward spillage of contrast agent was visible, which suggested a possible vessel puncture leading into the mediastinum. Unfortunately, postoperative hemorrhagic pericardial tamponade occurred and the patient developed cardiogenic shock. He experienced symptoms included chest tightness and breath shortness with a recorded blood pressure of 84/60mmHg. After draining 600 ml of bloody fluid through pericardiocentesis, the patient's symptoms alleviated and his condition improved. CONCLUSIONS: The case emphasizes the need for increased attention to iatrogenic endovascular injuries during catheter placement and endovascular treatment, such as causing pericardial hemorrhage leading to cardiac tamponade.


Assuntos
Tamponamento Cardíaco , Cateterismo Venoso Central , Derrame Pericárdico , Síndrome da Veia Cava Superior , Doenças Vasculares , Masculino , Humanos , Idoso , Síndrome da Veia Cava Superior/etiologia , Síndrome da Veia Cava Superior/cirurgia , Veia Cava Superior , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Cateterismo Venoso Central/efeitos adversos , Diálise Renal/efeitos adversos , Catéteres/efeitos adversos , Doença Iatrogênica
8.
J Evid Based Med ; 17(1): 207-223, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530771

RESUMO

Postoperative gastrointestinal disorder (POGD) was a common complication after surgery under anesthesia. Strategies in combination with Traditional Chinese Medicine and Western medicine showed some distinct effects but standardized clinical practice guidelines were not available. Thus, a multidisciplinary expert team from various professional bodies including the Perioperative and Anesthesia Professional Committees of the Chinese Association of Integrative Medicine (CAIM), jointly with Gansu Province Clinical Research Center of Integrative Anesthesiology/Anesthesia and Pain Medical Center of Gansu Provincial Hospital of Traditional Chinese Medicine and WHO Collaborating Center for Guideline Implementation and Knowledge Translation/Chinese Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) Center/Gansu Provincial Center for Medical Guideline Industry Technology/Evidence-based Medicine Center of Lanzhou University, was established to develop evidence-based guidelines. Clinical questions (7 background and 12 clinical questions) were identified through literature reviews and expert consensus meetings. Based on systematic reviews/meta-analyses, evidence quality was analyzed and the advantages and disadvantages of interventional measures were weighed with input from patients' preferences. Finally, 20 recommendations were developed through the Delphi-based consensus meetings. These recommendations included disease definitions, etiologies, pathogenesis, syndrome differentiation, diagnosis, and perioperative prevention and treatment.


Assuntos
Gastroenteropatias , Medicina Integrativa , Humanos , Medicina Tradicional Chinesa , Gastroenteropatias/prevenção & controle , Medicina Baseada em Evidências
9.
Sci Immunol ; 9(92): eadk4348, 2024 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-38335269

RESUMO

TCRαß+CD8αα+ intraepithelial lymphocytes (CD8αα+ αß IELs) are a specialized subset of T cells in the gut epithelium that develop from thymic agonist selected IEL precursors (IELps). The molecular mechanisms underlying the selection and differentiation of this T cell type in the thymus are largely unknown. Here, we found that Bcl6 deficiency in αß T cells resulted in the near absence of CD8αα+ αß IELs. BCL6 was expressed by approximately 50% of CD8αα+ αß IELs and by the majority of thymic PD1+ IELps after agonist selection. Bcl6 deficiency blocked early IELp generation in the thymus, and its expression in IELps was induced by thymic TCR signaling in an ERK-dependent manner. As a result of Bcl6 deficiency, the precursors of IELps among CD4+CD8+ double-positive thymocytes exhibited increased apoptosis during agonist selection and impaired IELp differentiation and maturation. Together, our results elucidate BCL6 as a crucial transcription factor during the thymic development of CD8αα+ αß IELs.


Assuntos
Linfócitos Intraepiteliais , Proteínas Proto-Oncogênicas c-bcl-6 , Receptores de Antígenos de Linfócitos T alfa-beta , Animais , Camundongos , Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Mucosa Intestinal , Linfócitos Intraepiteliais/metabolismo , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo
10.
Adv Healthc Mater ; : e2304523, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345186

RESUMO

Achieving hemostasis in penetrating and irregular wounds is challenging because the hemostasis factor cannot arrive at the bleeding site, and substantial bleeding will wash away the blood clot. Since the inherently gradual nature of blood clot formation takes time, a physical barrier is needed before blood clot formation. Herein, an ultra-light and shape memory hemostatic aerogel consisting of oxidized bacterial cellulose (OBC) and platelet extracellular vesicles (pVEs) is reported. The OBC-pVEs aerogel provides a physical barrier for the bleeding site by self-expansion, absorbing the liquid from blood to concentrate platelets and clotting factors and accelerating the clot formation by activating platelets and transforming fibrinogen into fibrin. In the rat liver and tail injury models, the blood loss decreases by 73% and 59%, and the bleeding times are reduced by 55% and 62%, respectively. OBC-pVEs aerogel has also been shown to accelerate wound healing. In conclusion, this work introduces an effective tool for treating deep, non-compressible, and irregular wounds and offers valuable strategies for trauma bleeding and wound treatment.

11.
FASEB J ; 38(2): e23387, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38193649

RESUMO

Human brain microvascular endothelial cells (HBMVECs) and microglia play critical roles in regulating cerebral homeostasis during ischemic stroke. However, the role of HBMVECs-derived exosomes in microglia polarization after stroke remains unknown. We isolated exosomes (Exos) from oxygen glucose deprivation (OGD)-exposed HBMVECs, before added them into microglia. Microglia polarization markers were tested using RT-qPCR or flow cytometry. Inflammatory cytokines were measured with ELISA. Endothelial cell damage was assessed by cell viability, apoptosis, apoptosis-related proteins, oxidative stress, and angiogenic activity using CCK-8, flow cytometry, western blot, ELISA, and endothelial tube formation assay, respectively. We also established middle cerebral artery occlusion (MCAO) mice model to examine the function of circ_0000495 on stroke in vivo. Our study found that HBMVECs-Exos reduced M2 markers (IL-10, CD163, and CD206), increased M1 markers (TNF-α, IL-1ß, and IL-12), CD86-positive cells, and inflammatory cytokines (TNF-α and IL-1ß), indicating the promotion of microglial M1-polarization. Microglial M1-polarization induced by HBMVECs-Exos reduced viability and promoted apoptosis and oxidative stress, revealing the aggravation of endothelial cell damage. However, circ_0000495 silencing inhibited HBMVECs-Exos-induced alterations. Mechanistically, circ_0000495 adsorbed miR-579-3p to upregulate toll-like receptor 4 (TLR4) in microglia; miR-579-3p suppressed HBMVECs-Exos-induced alterations via declining TLR4; furthermore, Yin Yang 1 (YY1) transcriptionally activated circ_0000495 in HBMVECs. Importantly, circ_0000495 aggravated ischemic brain injury in vivo via activating TLR4/nuclear factor-κB (NF-κB) pathway. Collectively, OGD-treated HBMVECs-Exos transmitted circ_0000495 to regulate miR-579-3p/TLR4/NF-κB axis in microglia, thereby facilitating microglial M1-polarization and endothelial cell damage.


Assuntos
Exossomos , MicroRNAs , Acidente Vascular Cerebral , Animais , Camundongos , Humanos , Células Endoteliais , Microglia , Receptor 4 Toll-Like/genética , NF-kappa B , Fator de Necrose Tumoral alfa , Encéfalo , Hipóxia , Oxigênio , Citocinas , MicroRNAs/genética
12.
J Agric Food Chem ; 72(3): 1630-1639, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38194497

RESUMO

Glycerol is an important platform compound with multidisciplinary applications, and glycerol production using low-cost sugar cane bagasse hydrolysate is promising. Candida glycerinogenes, an industrial yeast strain known for its high glycerol production capability, has been found to thrive in bagasse hydrolysate obtained through a simple treatment without detoxification. The engineered C. glycerinogenes exhibited significant resistance to furfural, acetic acid, and 3,4-dimethylbenzaldehyde within undetoxified hydrolysates. To further enhance glycerol production, genetic modifications were made to Candida glycerinogenes to enhance the utilization of xylose. Fermentation of undetoxified bagasse hydrolysate by CgS45 resulted in a glycerol titer of 40.3 g/L and a yield of 40.4%. This process required only 1 kg of bagasse to produce 93.5 g of glycerol. This is the first report of glycerol production using lignocellulose, which presents a new way for environmentally friendly industrial production of glycerol.


Assuntos
Candida , Glicerol , Pichia , Candida/metabolismo , Lignina/metabolismo , Fermentação , Saccharomyces cerevisiae/metabolismo , Xilose
13.
Neuroscience ; 538: 95-109, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-37778691

RESUMO

OBJECTIVE: Depression is a common mental illness. Neural stem cell-derived extracellular vesicles (NSC-EVs) are involved in repairing neuronal injury. We estimated the mechanism of miR-16-5p in depression rats. METHODS: EVs were extracted from NSCs. The depression rat model was established by corticosterone (CORT) induction and treated with NSC-EVs. The depression behavioral/pathological changes in rats were assessed using forced swimming test, open field test, sucrose consumption test and western blotting. The neuronal apoptosis in hippocampal tissue were detected. CORT-induced PC12 cell model was established. EV uptake by PC12 cells was measured and PC12 cell apoptosis was detected. The downstream targets of miR-16-5p were predicted and verified. The expressions of miR-16-5p and MYB in rats, PC12 cells, and EVs were measured. Functional rescue experiments were conducted to verify the role of miR-16-5p and MYB in PC12 cell apoptosis. RESULTS: CORT induction increased neuronal apoptosis in hippocampal tissue and induced depression-like behaviors in rats, while NSC-EV treatment improved depression-like behaviors and apoptosis in rats. In PC12 cells, NSC-EVs decreased CORT-induced PC12 cell apoptosis. NSC-EVs carried miR-16-5p into PC12 cells. miR-16-5p knockdown in EVs partially reversed the inhibitory effects of NSC-EVs on CORT-induced PC12 cell apoptosis. miR-16-5p targeted to inhibit MYB to repress CORT-induced PC12 cell apoptosis. In vivo experiments further verified that NSC-EVs reduced neuronal injury in CORT-induced depression rats via the miR-16-5p/MYB axis. CONCLUSION: NSC-EVs-mediated alleviation on neuronal injury by carrying miR-16-5p to target MYB was highly likely one of the mechanisms by which NSC-EVs mediated miR-16-5p in neuroprotection of depression rats.


Assuntos
Vesículas Extracelulares , MicroRNAs , Células-Tronco Neurais , Animais , Ratos , Corticosterona , Depressão/induzido quimicamente
16.
J Exp Med ; 221(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38047912

RESUMO

T follicular helper (Tfh) cells, essential for germinal center reactions, are not identical, with different phenotypes reported. Whether, when, and how they generate memory cells is still poorly understood. Here, through single-cell RNA-sequencing analysis of CXCR5+Bcl6+ Tfh cells generated under different conditions, we discovered, in addition to PD-1hi effector Tfh cells, a CD62L+PD1low subpopulation. CD62L-expressing Tfh cells developed independently from PD-1+ cells and not in direct contact with B cells. More importantly, CD62L+ Tfh cells expressed memory- and stemness-associated genes, and with better superior long-term survival, they readily generated PD-1hi cells in the recall response. Finally, KLF2 and IL7R, also highly expressed by CD62L+ Tfh cells, were required to regulate their development. Our work thus demonstrates a novel Tfh memory-like cell subpopulation, which may benefit our understanding of immune responses and diseases.


Assuntos
Linfócitos B , Células T Auxiliares Foliculares , Centro Germinativo , Fenótipo , Receptores CXCR5
17.
Front Immunol ; 14: 1293762, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111575

RESUMO

It is now understood that islet transplantation serves as a ß-cell replacement therapy for type 1 diabetes. Many factors impact the survival of transplanted islets, especially those related to the microenvironment. This review explored microenvironmental components, including vascular endothelial cells, inflammatory cytokines, and immune cells, and their profound effects on post-islet transplantation survival rates. Furthermore, it revealed therapeutic strategies aimed at targeting these elements. Current evidence suggests that vascular endothelial cells are pivotal in facilitating vascularization and nutrient supply and establishing a new microcirculation network for transplanted islets. Consequently, preserving the functionality of vascular endothelial cells emerges as a crucial strategy to enhance the survival of islet transplantation. Release of cytokines will lead to activation of immune cells and production and release of further cytokines. While immune cells hold undeniable significance in regulating immune responses, their activation can result in rejection reactions. Thus, establishing immunological tolerance within the recipient's body is essential for sustaining graft functionality. Indeed, future research endeavors should be directed toward developing precise strategies for modulating the microenvironment to achieve higher survival rates and more sustained transplantation outcomes. While acknowledging certain limitations inherent to this review, it provides valuable insights that can guide further exploration in the field of islet transplantation. In conclusion, the microenvironment plays a paramount role in islet transplantation. Importantly, we discuss novel perspectives that could lead to broader clinical applications and improved patient outcomes in islet transplantation.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Transplante das Ilhotas Pancreáticas , Humanos , Citocinas , Células Endoteliais , Diabetes Mellitus Tipo 1/terapia
19.
Aging Clin Exp Res ; 35(12): 3023-3031, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37923935

RESUMO

BACKGROUND: Observational studies have suggested an association between white blood cells (WBCs) and frailty, but considering the susceptibility to reverse causality and confounding, the causal direction and magnitude of this association remain ambiguous. Our aim was to investigate the causal effect of WBCs on frailty by means of a Mendelian randomization (MR) analysis. METHODS: Based on the genome-wide association study (GWAS) summary statistics data provided by the European Bioinformatics Institute (EBI), we carried out a two-sample MR study. We applied the genetically predicted independent WBCs from GWAS as a measure of exposure data. The Rockwood Frailty Index (FI) was used as outcome measure, which was derived from a meta-analysis from GWAS in UK Biobank European ancestry participants and Swedish TwinGene participants. Our study applied inverse variance weighted (IVW), weighted median, Mendelian randomization-Egger (MR-Egger) and outlier test (MR-PRESSO) methods to explore relationships between various WBCs and frailty. RESULTS: In our study, a possible causal relationship between eosinophil levels and frailty was demonstrated by two-sample MR analysis. Eosinophils were associated with FI (beta:0.0609; 95% CI 0.0382, 0.0836; P = 1.38E-07). Our results suggest that as the level of eosinophils increases, so does the risk of frailty. No meaningful causal relationship between neutrophils, lymphocytes, monocytes or basophils and FI was found in the MR results (P > 0.05). CONCLUSIONS: According to this MR study, higher eosinophil counts are related to an increased risk of frailty. To validate these findings and investigate the mechanisms underlying these connections, future studies are warranted.


Assuntos
Fragilidade , Humanos , Fragilidade/genética , Estudo de Associação Genômica Ampla , Leucócitos , Monócitos , Predisposição Genética para Doença
20.
Sci Immunol ; 8(88): eadh1306, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37862431

RESUMO

Overcoming CD8+ T cell exhaustion is critical in cancer immunotherapy. Recently, an intratumor stem/progenitor-like CD8+ T cell (Tprog cell) population that mediates the persistence of antitumor responses has been defined, which can further develop into a terminally differentiated CD8+ T cell (Tterm cell) subpopulation with potent cytotoxic functions. Tprog cells are the main responders to immune checkpoint blockade therapies, yet how extrinsic signals via transcription factors control Tprog cell generation and persistence in tumors is unclear. Here, we found that BCL6 inhibits tumor-specific Tterm cell generation from Tprog cell downstream of TCF1. We show that Bcl6 deficiency reduced the persistence of Tprog cells, without affecting their generation, thus abrogating long-term tumor control. High-level BCL6 expression was observed in tumor-specific T cells in draining lymph nodes (LNs) and was associated with T cell exhaustion. This was observed in TOX+TCF1+ Tprog cells in both LNs and tumors. BCL6 expression in CD8+ T cells was up-regulated by TGF-ß-SMAD2 signaling but down-regulated by the IL-2-STAT5 pathway. Mechanistically, BCL6 transcriptionally repressed the expression of Tterm cell-associated genes and induced those of Tprog cell-related genes, in a manner antagonistic to BLIMP1. Prdm1 deficiency also promoted the Tprog cell program and greatly improved the efficacy of anti-PD-1 therapy. Thus, we identified the TGF-ß-BCL6 and IL-2-BLIMP1 antagonistic pathways in regulation of antitumor CD8+ T cells, which may benefit the development of long-lasting and effective cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Interleucina-2 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta , Proteínas Proto-Oncogênicas c-bcl-6/genética
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