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1.
Open Life Sci ; 19(1): 20220915, 2024.
Article in English | MEDLINE | ID: mdl-39071493

ABSTRACT

The present work focused on investigating the role of the altered expression of complement C1s in proliferation and apoptosis of esophageal squamous cell carcinoma (ESCC) cells and explore its biological functions in ESCC, so as to lay a theoretical foundation and provide certain clinical reference for diagnosing and treating ESCC. Complement C1s expression within ESCC was assessed, and its clinical pathological characteristics in ESCC patients were analyzed. Subsequently, in vitro experiments were performed to further explore the mechanisms by which complement C1s affected ESCC. According to the results, complement C1s expression within ESCC markedly increased relative to adjacent non-cancerous samples. High C1s expression showed positive relation to race, residual lesion, and tumor location of ESCC patients. Complement C1s affected ESCC cell proliferation and apoptosis. Notably, C1s knockdown significantly inhibited ESCC cell proliferation and enhanced their apoptosis. C1s suppressed ESCC cell proliferation via Wnt1/ß-catenin pathway and promoted their apoptosis through modulating the expression of Bcl2, Bax, and cleaved-caspase3.

2.
Small Methods ; : e2400640, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39041431

ABSTRACT

La3-xTe4 is a very promising high-temperature candidate applied in next-generation Radioisotope Thermoelectric Generators (RTGs). Conventional synthesis of such materials is based on the mechanochemical method, which makes the sample difficult to purify due to the high-energy ball milling. In this report, a novel synthetic method is developed, which utilizes Te-vapor transport and solid-phase diffusion to efficiently produce the RE3-xTe4 phases (RE = La, Ce, Pr, Nd). Notably, this method obviates the requirement for high-energy ball-milling instruments, conventionally indispensable in the mechanochemical syntheses. For as-synthesized La2.74Te4 material, a high figure of merit of 1.5 is achieved at 1073 K, owning to the reduced electronic thermal conductivity with metal impurities well eliminated.

3.
Front Mol Biosci ; 11: 1391046, 2024.
Article in English | MEDLINE | ID: mdl-38841190

ABSTRACT

Dendritic cells (DCs) are involved in the initiation and maintenance of immune responses against malignant cells by recognizing conserved pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) through pattern recognition receptors (PRRs). According to recent studies, tumor cell-derived DNA molecules act as DAMPs and are recognized by DNA sensors in DCs. Once identified by sensors in DCs, these DNA molecules trigger multiple signaling cascades to promote various cytokines secretion, including type I IFN, and then to induce DCs mediated antitumor immunity. As one of the potential attractive strategies for cancer therapy, various agonists targeting DNA sensors are extensively explored including the combination with other cancer immunotherapies or the direct usage as major components of cancer vaccines. Moreover, this review highlights different mechanisms through which tumor-derived DNA initiates DCs activation and the mechanisms through which the tumor microenvironment regulates DNA sensing of DCs to promote tumor immune escape. The contributions of chemotherapy, radiotherapy, and checkpoint inhibitors in tumor therapy to the DNA sensing of DCs are also discussed. Finally, recent clinical progress in tumor therapy utilizing agonist-targeted DNA sensors is summarized. Indeed, understanding more about DNA sensing in DCs will help to understand more about tumor immunotherapy and improve the efficacy of DC-targeted treatment in cancer.

4.
ACS Appl Mater Interfaces ; 16(22): 28886-28895, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38771993

ABSTRACT

Mg3Bi2-based materials are a very promising substitute for current commercial Bi2Te3 thermoelectric alloys. The successful growth of Mg3Bi2-based single crystals with high room-temperature performance is especially significant for practical applications. Previous studies indicated that the effective suppression of Mg defects in Mg3Bi2-based materials was crucial for high performance, which was usually realized by applying excessive Mg during syntheses. However, utilization of excessive Mg generates Mg-rich phases between the crystalline boundaries and is unfavorable for the long-term stability of the materials. Here, bulk single crystals with a low-content Mg component such as Mg3.1Bi1.49Sb0.5Te0.01 were successfully grown. For compensating Mg defects, Li was chosen as the additional electron dopant. The results indicate that Li is a very effective electron compensator when low-concentration doping is applied. For high-concentration doping, Mg atoms in the lattice are substituted by Li, leading to decreased electron concentration again. This strategy is very significant for improving the room-temperature performance of Mg3Bi2-based materials. As a result, a record-high figure of merit of 1.05 at 300 K is achieved for Mg3+xLi0.003Bi1.49Sb0.5Te0.01 single crystals.

5.
CNS Neurosci Ther ; 30(4): e14696, 2024 04.
Article in English | MEDLINE | ID: mdl-38668740

ABSTRACT

AIMS: Excessive neuroinflammation mediated mainly by microglia plays a crucial role in ischemic stroke. AZD1390, an ataxia telangiectasia mutated (ATM) specific inhibitor, has been shown to promote radio-sensitization and survival in central nervous system malignancies, while the role of AZD1390 in ischemic stroke remains unknown. METHODS: Real-time PCR, western blot, immunofluorescence staining, flow cytometry and enzyme-linked immunosorbent assays were used to assess the activation of microglia and the release of inflammatory cytokines. Behavioral tests were performed to measure neurological deficits. 2,3,5-Triphenyltetrazolium chloride staining was conducted to assess the infarct volume. The activation of NF-κB signaling pathway was explored through immunofluorescence staining, western blot, co-immunoprecipitation and proximity ligation assay. RESULTS: The level of pro-inflammation cytokines and activation of NF-κB signaling pathway was suppressed by AZD1390 in vitro and in vivo. The behavior deficits and infarct size were partially restored with AZD1390 treatment in experimental stroke. AZD1390 restrict ubiquitylation and sumoylation of the essential regulatory subunit of NF-κB (NEMO) in an ATM-dependent and ATM-independent way respectively, which reduced the activation of the NF-κB pathway. CONCLUSION: AZD1390 suppressed NF-κB signaling pathway to alleviate ischemic brain injury in experimental stroke, and attenuated microglia activation and neuroinflammation, which indicated that AZD1390 might be an attractive agent for the treatment of ischemic stroke.


Subject(s)
Microglia , Neuroinflammatory Diseases , Pyridines , Quinolones , Animals , Microglia/drug effects , Microglia/metabolism , Neuroinflammatory Diseases/drug therapy , Neuroinflammatory Diseases/metabolism , Male , Mice , Mice, Inbred C57BL , Brain Ischemia/drug therapy , Brain Ischemia/metabolism , Ataxia Telangiectasia Mutated Proteins/metabolism , Ataxia Telangiectasia Mutated Proteins/antagonists & inhibitors , NF-kappa B/metabolism , NF-kappa B/antagonists & inhibitors , Cytokines/metabolism , Signal Transduction/drug effects
6.
Protein J ; 43(3): 447-463, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38622349

ABSTRACT

The thymus is the key immune organ for the development of T cells. Different populations of thymic stromal cells interact with T cells, thereby controlling the dynamic development of T cells through their differentiation and function. Proteostasis represents a balance between protein expression, folding, and modification and protein clearance, and its fluctuation usually depends at least partially on related protein regulatory systems for further survival and effects. However, in terms of the substantial requirement for self-antigens and their processing burden, increasing evidence highlights that protein regulation contributes to the physiological effects of thymic stromal cells. Impaired proteostasis may expedite the progression of thymic involution and dysfunction, accompanied by the development of autoimmune diseases or thymoma. Hence, in this review, we summarize the regulation of proteostasis within different types of thymic stromal cells under physiological and pathological conditions to identify potential targets for thymic regeneration and immunotherapy.


Subject(s)
Proteostasis , Stromal Cells , Thymus Gland , Humans , Thymus Gland/metabolism , Thymus Gland/cytology , Stromal Cells/metabolism , Animals , Autoimmune Diseases/metabolism , Autoimmune Diseases/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/immunology
7.
Clin Exp Immunol ; 217(2): 136-150, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38651831

ABSTRACT

CD8 T cells are crucial adaptive immune cells with cytotoxicity to fight against pathogens or abnormal self-cells via major histocompatibility complex class I-dependent priming pathways. The composition of the memory CD8 T-cell pool is influenced by various factors. Physiological aging, chronic viral infection, and autoimmune diseases promote the accumulation of CD8 T cells with highly differentiated memory phenotypes. Accumulating studies have shown that some of these memory CD8 T cells also exhibit innate-like cytotoxicity and upregulate the expression of receptors associated with natural killer (NK) cells. Further analysis shows that these NK-like CD8 T cells have transcriptional profiles of both NK and CD8 T cells, suggesting the transformation of CD8 T cells into NK cells. However, the specific induction mechanism underlying NK-like transformation and the implications of this process for CD8 T cells are still unclear. This review aimed to deduce the possible differentiation model of NK-like CD8 T cells, summarize the functions of major NK-cell receptors expressed on these cells, and provide a new perspective for exploring the role of these CD8 T cells in health and disease.


Subject(s)
Adaptive Immunity , CD8-Positive T-Lymphocytes , Immunity, Innate , Immunologic Memory , Killer Cells, Natural , Humans , CD8-Positive T-Lymphocytes/immunology , Killer Cells, Natural/immunology , Immunologic Memory/immunology , Immunity, Innate/immunology , Animals , Adaptive Immunity/immunology , Cell Differentiation/immunology , Cytotoxicity, Immunologic
8.
J Physiol ; 602(10): 2265-2285, 2024 May.
Article in English | MEDLINE | ID: mdl-38632887

ABSTRACT

The mechanisms governing brain vascularization during development remain poorly understood. A key regulator of developmental vascularization is delta like 4 (DLL4), a Notch ligand prominently expressed in endothelial cells (EC). Exposure to hyperoxia in premature infants can disrupt the development and functions of cerebral blood vessels and lead to long-term cognitive impairment. However, its role in cerebral vascular development and the impact of postnatal hyperoxia on DLL4 expression in mouse brain EC have not been explored. We determined the DLL4 expression pattern and its downstream signalling gene expression in brain EC using Dll4+/+ and Dll4+/LacZ mice. We also performed in vitro studies using human brain microvascular endothelial cells. Finally, we determined Dll4 and Cldn5 expression in mouse brain EC exposed to postnatal hyperoxia. DLL4 is expressed in various cell types, with EC being the predominant one in immature brains. Moreover, DLL4 deficiency leads to persistent abnormalities in brain microvasculature and increased vascular permeability both in vivo and in vitro. We have identified that DLL4 insufficiency compromises endothelial integrity through the NOTCH-NICD-RBPJ-CLDN5 pathway, resulting in the downregulation of the tight junction protein claudin 5 (CLDN5). Finally, exposure to neonatal hyperoxia reduces DLL4 and CLDN5 expression in developing mouse brain EC. We reveal that DLL4 is indispensable for brain vascular development and maintaining the blood-brain barrier's function and is repressed by neonatal hyperoxia. We speculate that reduced DLL4 signalling in brain EC may contribute to the impaired brain development observed in neonates exposed to hyperoxia. KEY POINTS: The role of delta like 4 (DLL4), a Notch ligand in vascular endothelial cells, in brain vascular development and functions remains unknown. We demonstrate that DLL4 is expressed at a high level during postnatal brain development in immature brains and DLL4 insufficiency leads to abnormal cerebral vasculature and increases vascular permeability both in vivo and in vitro. We identify that DLL4  regulates endothelial integrity through NOTCH-NICD-RBPJ-CLDN5 signalling. Dll4 and Cldn5 expression are decreased in mouse brain endothelial cells exposed to postnatal hyperoxia.


Subject(s)
Adaptor Proteins, Signal Transducing , Animals, Newborn , Calcium-Binding Proteins , Claudin-5 , Endothelial Cells , Hyperoxia , Receptors, Notch , Animals , Humans , Mice , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Brain/metabolism , Brain/blood supply , Brain/growth & development , Calcium-Binding Proteins/metabolism , Calcium-Binding Proteins/genetics , Cells, Cultured , Claudin-5/metabolism , Claudin-5/genetics , Endothelial Cells/metabolism , Hyperoxia/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , Mice, Inbred C57BL , Receptors, Notch/metabolism , Receptors, Notch/genetics , Signal Transduction
10.
Opt Lett ; 48(23): 6088-6091, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38039198

ABSTRACT

In this Letter, we propose a novel, to the best of our knowledge, dual-mode tunable absorber that utilizes quasi-bound states in the continuum (q-BIC) based on the periodically arranged silicon cylinders tetramer. By introducing asymmetry perturbation through manipulating the diameters of diagonal cylinders in the all-dielectric structure, the symmetry-protected BIC (SP-BIC) transforms into q-BIC, leading to the emergence of one transmission and one reflection Fano-like resonant mode. The relationship between the quality factor of each mode and the asymmetry parameter α is analyzed, revealing an exponential dependence with an exponent of -1.75, i.e., Q ∝ α-1.75. To explain the underlying physics, multipole decomposition analysis and Aleksandra's theory are applied. Subsequently, a monolayer graphene is introduced to the all-dielectric structure to demonstrate the application of the dual-mode tunable absorber. When the critical coupling condition is satisfied, each mode can achieve the theoretical maximum absorption, demonstrating the distinctive capability of our proposed absorber for tuning and efficient light absorption. This research provides valuable insights into light-matter interactions and opens up possibilities for optical modulation and the development of graphene-based devices.

11.
J Neuroinflammation ; 20(1): 260, 2023 Nov 11.
Article in English | MEDLINE | ID: mdl-37951917

ABSTRACT

BACKGROUND: Emerging evidence has shown that myeloid cells that infiltrate into the peri-infarct region may influence the progression of ischemic stroke by interacting with microglia. Properdin, which is typically secreted by immune cells such as neutrophils, monocytes, and T cells, has been found to possess damage-associated molecular patterns (DAMPs) properties and can perform functions unrelated to the complement pathway. However, the role of properdin in modulating microglia-mediated post-stroke neuroinflammation remains unclear. METHODS: Global and conditional (myeloid-specific) properdin-knockout mice were subjected to transient middle cerebral artery occlusion (tMCAO). Histopathological and behavioral tests were performed to assess ischemic brain injury in mice. Single-cell RNA sequencing and immunofluorescence staining were applied to explore the source and the expression level of properdin. The transcriptomic profile of properdin-activated primary microglia was depicted by transcriptome sequencing. Lentivirus was used for macrophage-inducible C-type lectin (Mincle) silencing in microglia. Conditioned medium from primary microglia was administered to primary cortex neurons to determine the neurotoxicity of microglia. A series of cellular and molecular biological techniques were used to evaluate the proinflammatory response, neuronal death, protein-protein interactions, and related signaling pathways, etc. RESULTS: The level of properdin was significantly increased, and brain-infiltrating neutrophils and macrophages were the main sources of properdin in the ischemic brain. Global and conditional myeloid knockout of properdin attenuated microglial overactivation and inflammatory responses at the acute stage of tMCAO in mice. Accordingly, treatment with recombinant properdin enhanced the production of proinflammatory cytokines and augmented microglia-potentiated neuronal death in primary culture. Mechanistically, recombinant properdin served as a novel ligand that activated Mincle receptors on microglia and downstream pathways to drive primary microglia-induced inflammatory responses. Intriguingly, properdin can directly bind to the microglial Mincle receptor to exert the above effects, while Mincle knockdown limits properdin-mediated microglial inflammation. CONCLUSION: Properdin is a new medium by which infiltrating peripheral myeloid cells communicate with microglia, further activate microglia, and exacerbate brain injury in the ischemic brain, suggesting that targeted disruption of the interaction between properdin and Mincle on microglia or inhibition of their downstream signaling may improve the prognosis of ischemic stroke.


Subject(s)
Brain Injuries , Brain Ischemia , Ischemic Stroke , Mice , Animals , Microglia/metabolism , Ischemic Stroke/metabolism , Properdin/metabolism , Properdin/pharmacology , Neuroinflammatory Diseases , Macrophages/metabolism , Infarction, Middle Cerebral Artery/pathology , Brain Injuries/metabolism , Brain Ischemia/metabolism , Mice, Inbred C57BL
12.
Lasers Med Sci ; 38(1): 279, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38030741

ABSTRACT

The study aimed to investigate the clinical effect of transurethral columnar balloon dilation of the prostate combined with holmium laser in the treatment of bladder neck contracture (BNC). This retrospective study included 41 patients with BNC, who had been treated with transurethral columnar balloon dilation and holmium laser in our hospital from June 2020 to June 2022. Admission, operation, and discharge of all the patients were completed in 24 h. The patients' satisfaction, postoperative complications, and chronic pain after operation were followed up. Clinical parameters, such as International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), quality of life (QoL), and post-void residual volume (PVR) in pre-operation, 1 month and 6 months after operation were recorded. All patients underwent the operations successfully. Six patients experienced urge incontinence and one patient experienced recurrence of BNC after 12 months. At 1 month and 6 months after the operation, IPSS, QoL, PVR, and Qmax of the patients were significantly better than those before the operation (P < 0.05). Transurethral columnar balloon dilation of the prostate combined with holmium laser can effectively treat BNC with simple performance and satisfactory clinical effects. It is a minimally invasive treatment that can be conducted by simple day surgery.


Subject(s)
Contracture , Laser Therapy , Lasers, Solid-State , Prostatic Hyperplasia , Transurethral Resection of Prostate , Male , Humans , Prostate/surgery , Urinary Bladder/surgery , Lasers, Solid-State/therapeutic use , Quality of Life , Ambulatory Surgical Procedures , Retrospective Studies , Dilatation , Prostatic Hyperplasia/surgery , Prostatic Hyperplasia/complications , Contracture/surgery , Contracture/complications , Treatment Outcome
13.
Cells ; 12(18)2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37759454

ABSTRACT

Angiogenesis plays a critical role in various physiological and pathological processes and is regulated by VEGF. Histone Deacetylase 6 (HDAC6) is a class IIB HDAC that regulates cytoplasmic signaling through deacetylation and is emerging as a target for modulating angiogenesis. We investigated the hypothesis that VEGF-induced endothelial cell (EC) NOTCH signaling is regulated by HDAC6 through acetylation of NOTCH intracellular cytoplasmic domain (NICD). In pulmonary endothelial cells (EC), VEGF-induced activation of the NICD transcriptional response was regulated by ERK1/2 and ADAM 17 and required DLL4. While HDAC6 inhibition induced the acetylation of NICD and stabilized NICD, it repressed NICD-SNW1 binding required for the NOTCH transcriptional responses. In vitro experiments showed that HDAC6 inhibition inhibited lung EC angiogenesis, and neonatal mice treated with a systemic HDAC6 inhibitor had significantly altered angiogenesis and alveolarization. These findings shed light on the role of HDAC6 in modulating VEGF-induced angiogenesis through acetylation and repression of the transcriptional regulators, NICD and SNW1.

14.
J Orthop Surg Res ; 18(1): 500, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37454090

ABSTRACT

BACKGROUND: The function of mesenchymal stem cells (MSCs) from patients with osteoporosis (OP) is impaired and worsens in patients with type 2 diabetes mellitus (T2DM). Icariin (ICA) is the major active flavonoid glucoside isolated from traditional Chinese herbal Epimedium pubescens, and confirmed able to improve bone mass of OP patients. OBJECTIVE: To investigate the effect of ICA on the proliferation and osteogenic differentiation of bone-derived MSCs (BMSCs) from patients with OP and T2DM and uncover the potential mechanism. METHODS: BMSCs were treated with ICA, and proliferation and osteogenic potency were evaluated using the 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and detection of osteogenic markers (ALP, RUNX2, SPP1, COL1A1, and mineralized nodules) was performed. RNA sequencing and bioinformatic analysis were performed to identify differentially expressed genes (DEGs) after ICA treatment and screen proliferation- and osteogenic differentiation-related processes. Gene gain and loss were performed to confirm the role of the key candidate gene. RESULTS: ICA significantly promoted the proliferation and osteogenic differentiation of BMSCs. A total of 173 DEGs were identified after ICA treatment. Six DEGs (GLI-1, IGF2, BMP6, WNT5A, PTHLH, and MAPK14) enriched in both proliferation- and osteogenic differentiation-related processes were screened; GLI-1 had the highest validated |log2FC| value. Overexpression of GLI-1 enhanced the proliferation and osteogenic differentiation of BMSCs, and knockdown of GLI-1 weakened the positive effect of ICA on BMSCs. CONCLUSION: ICA promoted the proliferation and osteogenic differentiation of impaired BMSCs by upregulating GLI-1.


Subject(s)
Diabetes Mellitus, Type 2 , Mesenchymal Stem Cells , Osteoporosis , Humans , Osteogenesis/genetics , Cell Differentiation , Osteoporosis/drug therapy , Osteoporosis/genetics , Cell Proliferation/genetics , Cells, Cultured
15.
iScience ; 26(7): 107268, 2023 Jul 21.
Article in English | MEDLINE | ID: mdl-37496671

ABSTRACT

Ischemic stroke is the second leading cause of death worldwide, and there are limited effective treatment strategies. QHRD106, a polyethyleneglycol (PEG)-modified long-acting tissue kallikrein preparation, has not been reported previously. In this study, we aimed to investigate the therapeutic effect of QHRD106 in ischemic stroke and its possible mechanism. We found that QHRD106 treatment alleviated brain injury after stroke via bradykinin (BK) receptor B2 (B2R) instead of BK receptor B1 (B1R). Mechanistically, QHRD106 reduced high-mobility group box 1 (HMGB1)-induced apoptosis and inflammation after ischemic stroke in vivo and in vitro. Moreover, we confirmed that QHRD106 reduced the level of acetylated HMGB1 and reduced the binding between heat shock protein 90 alpha family class A member 1 (HSP90AA1) and HMGB1, thus inhibiting the translocation and release of HMGB1. In summary, these findings indicate that QHRD106 treatment has therapeutic potential for cerebral ischemic stroke.

16.
Mitochondrion ; 71: 64-75, 2023 07.
Article in English | MEDLINE | ID: mdl-37276954

ABSTRACT

As the cell's energy factory and metabolic hub, mitochondria are critical for ATP synthesis to maintain cellular function. Mitochondria are highly dynamic organelles that continuously undergo fusion and fission to alter their size, shape, and position, with mitochondrial fusion and fission being interdependent to maintain the balance of mitochondrial morphological changes. However, in response to metabolic and functional damage, mitochondria can grow in size, resulting in a form of abnormal mitochondrial morphology known as megamitochondria. Megamitochondria are characterized by their considerably larger size, pale matrix, and marginal cristae structure and have been observed in various human diseases. In energy-intensive cells like hepatocytes or cardiomyocytes, the pathological process can lead to the growth of megamitochondria, which can further cause metabolic disorders, cell damage and aggravates the progression of the disease. Nonetheless, megamitochondria can also form in response to short-term environmental stimulation as a compensatory mechanism to support cell survival. However, extended stimulation can reverse the benefits of megamitochondria leading to adverse effects. In this review, we will focus on the findings of the different roles of megamitochondria, and their link to disease development to identify promising clinical therapeutic targets.


Subject(s)
Metabolic Diseases , Mitochondria , Humans , Mitochondrial Swelling , Mitochondria/metabolism , Hepatocytes/metabolism , Mitochondrial Membranes/metabolism , Mitochondrial Dynamics
18.
Inorg Chem ; 62(19): 7333-7341, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37133387

ABSTRACT

Zintl compounds often feature complex structural fragments and small band gaps, favoring promising thermoelectric properties. In this work, a new phase Ca2ZnSb2 is synthesized and characterized to be a LiGaGe-type structure. It is isotypic to Yb2MnSb2 with half vacancies at transition metal sites and undergoes a phase transition to Ca9Zn4+xSb9 after annealing. Interestingly, Ca2ZnSb2 and Yb2MnSb2 are amenable to diverse doping mechanisms at different sites. Here, by substituting smaller Li on cation sites, two novel layered compounds Ca1.84(1)Li0.16(1)Zn0.84(1)Sb2 and Yb1.82(1)Li0.18(1)Mn0.96(1)Sb2 with the P63/mmc space group are discovered, which can be viewed as derivatives of LiGaGe type. Despite having lower occupancy, the structural stability is improved compared with the prototype compounds owing to the reduced interlayered distances. Besides, the band structure analyses demonstrate that the bands near the Fermi level are mainly governed by the interlayered interaction. Due to the highly disordered structure, Yb1.82Li0.18Mn0.96Sb2 features ultralow thermal conductivity from 0.79 to 0.47 W·m-1·K-1 among the testing range; in addition, a remarkable Seebeck coefficient of 270.77 µV·K-1 at 723 K is observed. The discovery of the Ca2ZnSb2 phase enriches the 2-1-2 map, and the size effect induced by cations provides new ideas for material designing.

19.
Nat Cell Biol ; 25(5): 726-739, 2023 05.
Article in English | MEDLINE | ID: mdl-37142791

ABSTRACT

Stimulator of interferon genes (STING) orchestrates the production of proinflammatory cytokines in response to cytosolic double-stranded DNA; however, the pathophysiological significance and molecular mechanism underlying the folding and maturation of nascent STING protein at the endoplasmic reticulum (ER) remain unknown. Here we report that the SEL1L-HRD1 protein complex-the most conserved branch of ER-associated degradation (ERAD)-is a negative regulator of the STING innate immunity by ubiquitinating and targeting nascent STING protein for proteasomal degradation in the basal state. SEL1L or HRD1 deficiency in macrophages specifically amplifies STING signalling and immunity against viral infection and tumour growth. Mechanistically, nascent STING protein is a bona fide substrate of SEL1L-HRD1 in the basal state, uncoupled from ER stress or its sensor inositol-requiring enzyme 1α. Hence, our study not only establishes a key role of SEL1L-HRD1 ERAD in innate immunity by limiting the size of the activable STING pool, but identifies a regulatory mechanism and therapeutic approach to targeting STING.


Subject(s)
Endoplasmic Reticulum-Associated Degradation , Ubiquitin-Protein Ligases , Ubiquitin-Protein Ligases/metabolism , Proteins/metabolism , Endoplasmic Reticulum/metabolism , Immunity, Innate
20.
J Clin Invest ; 133(11)2023 06 01.
Article in English | MEDLINE | ID: mdl-37097753

ABSTRACT

Neonatal herpes simplex virus (HSV) infection is a devastating disease with substantial morbidity and mortality. The genetic basis of susceptibility to HSV in neonates remains undefined. We evaluated a male infant with neonatal skin/eye/mouth (SEM) HSV-1 disease, who had complete recovery after acyclovir but developed HSV-1 encephalitis at 1 year of age. An immune workup showed an anergic PBMC cytokine response to TLR3 stimulation but no other TLRs. Exome sequencing identified rare missense variants in IFN-regulatory factor 7 (IRF7) and UNC-93 homolog B1 (UNC93B1). PBMC single-cell RNA-Seq done during childhood revealed decreased expression of several innate immune genes and a repressed TLR3 pathway signature at baseline in several immune cell populations, including CD14 monocytes. Functional studies in fibroblasts and human leukemia monocytic THP1 cells showed that both variants individually suppressed TLR3-driven IRF3 transcriptional activity and the type I IFN response in vitro. Furthermore, fibroblasts expressing the IRF7 and UNC93B1 variants had higher intracellular viral titers with blunting of the type I IFN response upon HSV-1 challenge. This study reports an infant with recurrent HSV-1 disease complicated by encephalitis associated with deleterious variants in the IRF7 and UNC93B1 genes. Our results suggest that TLR3 pathway mutations may predispose neonates to recurrent, severe HSV.


Subject(s)
Encephalitis, Herpes Simplex , Herpes Simplex , Herpesvirus 1, Human , Interferon Type I , Humans , Infant , Infant, Newborn , Male , Encephalitis, Herpes Simplex/genetics , Herpes Simplex/genetics , Leukocytes, Mononuclear/metabolism , Membrane Transport Proteins , Toll-Like Receptor 3/genetics
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