Blockade of CD300A enhances the ability of human NK cells to lyse hematologic malignancies

Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(NK) cells targeting hematologic malignancies(HMs).Methods: We implemented a stimulation system involving the CD300A ligand, phosphatidylserine(PS), exposed to the outer surface of malignant cells. Additionally, we utilized CD300A overexpression, a CD300A blocking system, and a xenotransplantation model to evaluate the impact of CD300A on NK cell efficacy against HMs in in vitro and in vivo settings. Furthermore, we explored the association between CD300A and HM progression in patients.Results: Our findings indicated that PS hampers the function of NK cells. Increased CD300A expression inhibited HM lysis by NK cells. CD300A overexpression shortened the survival of HM-xenografted mice by impairing transplanted NK cells. Blocking PS–CD300A signals with antibodies significantly amplified the expression of lysis function-related proteins and effector cytokines in NK cells, thereby augmenting the ability to lyse HMs. Clinically, heightened CD300A expression correlated with shorter survival and an “exhausted” phenotype of intratumoral NK cells in patients with HMs or solid tumors.Conclusions: These results propose CD300A as a potential target for invigorating NK cell-based treatments against HMs.

群体感应抑制剂对费氏弧菌生物荧光随时间变化Hormesis效应的机制探究

群体感应抑制剂(quorum sensing inhibitor,QSIs)是作用于细菌群体感应系统的一类新型抗菌药物。目前关于QSIs引起Hormesis效应的机制探究较少。本文以费氏弧菌(Aliivibrio fischeri,A.fischeri)为模式生物,测定了3种高丝氨酸内酯(N-Acyl homoserine lactone,AHL)类QSIs(AHL-QSIs)对A.fischeri生物荧光的影响,发现AHL-QSIs对A.fischeri生物荧光产生了随时间变化的Hormesis效应。通过测定AHL-QSIs对A.fischeri生长量、相关蛋白表达量及模拟发光反应的影响,推测随时间变化Hormesis的机制如下:AHL-QSIs在低浓度时可以通过增强荧光素酶的活性进而促进个体发光反应,最终刺激A.fischeri的生物荧光;而当AHL-QSIs处于高浓度时,更多的AHL-QSIs不仅会通过改变细胞膜功能抑制细菌的生长,还可以与C6竞争结合LuxR影响荧光素酶的含量,最终抑制A.fischeri的生物荧光;AHL-QSIs对A.fischeri生物荧光的刺激作用和抑制作用会随细菌生长阶段状态的不同而发生变化,最终导致了随时间变化的Hormesis效应。研究结果可为今后AHL-QSIs的生态风险及其进一步的广泛应用提供一定的数据基础和理论依据。

Propagation characteristics of oblique incidence terahertz wave through non-uniform plasma

The propagation characteristics of oblique incidence terahertz(THz) waves through non-uniform plasma are investigated by the shift-operator finite-difference time-domain(SO-FDTD) method combined with the phase matching condition.The electron density distribution of the non-uniform plasma is assumed to be in a Gaussian profile. Validation of the present method is performed by comparing the results with those obtained by an analytical method for a homogeneous plasma slab.Then the effects of parameters of THz wave and plasma layer on the propagation properties are analyzed. It is found that the transmission coefficients greatly depend on the incident angle as well as on the thickness of the plasma, while the polarization of the incident wave has little influence on the propagation process in the range of frequency considered in this paper. The results confirm that the THz wave can pass through the plasma sheath effectively under certain conditions,which makes it a potential candidate to overcome the ionization blackout problem.

Trispecific killer engager 161519 enhances natural killer cell function and provides anti-tumor activity against CD19-positive cancers

Objective:Natural killer(NK)cells have gained considerable attention due to their potential in treating"cold tumors,"and are therefore considered as one of the new strategies for curing cancer,by using worldwide development of their new possibilities and interventions with NK cell-related therapeutic products.Methods:We constructed a trispecific killer engager(TriKE)consisting of anti-CD16,IL-15,and anti-CD19.This TriKE was designed to attract CD19^(+)tumor cells to CD16^(+)NK cells,whereas IL-15 sustained the proliferation,development,and survival of NK cells.Results:Treatment with 161519 TriKE in the presence of CD19^(+)targets upregulated expression of CD69,CD107 a,TRAIL,IFN-γ,and TNF-α in NK cells,and significantly improved the proliferation and cytotoxicity of NK cells.NK cells"armed"with 161519 TriKE showed stronger cytolysis against CD19+targets compared with that of"unarmed"NK cells.A preclinical model of B-cell lymphoma in human peripheral blood mononuclear cell-reconstituted xenograft mice showed significant inhibition of tumor growth and prolonged overall survival after treatment with 161519 TriKE,when compared with that in control mice or mice treated with 1619 BiKE.Combined use of IL-2 was a more effective treatment with 1619 BiKE,when compared with that using 161519 TriKE.Conclusions:The newly generated 161519 TriKE enhanced the proliferation,activation,cytokine secretion,and cytotoxicity of NK cells in the presence of CD19+tumor cells.The 161519 TriKE aided inhibition of tumor growth and prolonged the overall survival of murine xenografts,and could be used to treat CD19-positive cancers.

Panoramic comparison between NK cells in healthy and cancerous liver through single-cell RNA sequencing

Objective:NK cells play crucial roles in the immune defense mechanisms against viral infections and transformed cells.However,the developmental progression,transcriptomic landscape,and functional subtypes of liver NK cells are not well defined.Hepatocellular carcinoma(HCC)accounts for approximately 80%of primary liver cancer worldwide,yet the biological characteristics of NK cells in the HCC environment are unclear.Therefore,we aimed to determine these cells’roles in tumorigenesis and prognosis.Methods:We compared the single-cell RNA sequencing profiles of NK cells purified from blood(n=1),healthy liver tissues(n=3),HCC tumor tissues(n=4),and peritumor liver tissues(n=1)to identify NK cell subsets.Furthermore,we performed bioinformatics analysis by using The Cancer Genome Atlas(TCGA)data to identify prognostic biomarkers simultaneously overexpressed in the blood and tumor tissues of patients with HCC.Results:Transcriptomic analysis revealed 5 NK cell subsets(L1-NK-CD56bright,L2-NK-CD56dim,L3-NK-HLA,L4-LrNK-FCGR3A,and L5-LrNK-XCL1)in the healthy liver tissues.However,the transitional L3 subset and the CXCR6+CD16+L4 subset with strong anti-tumor activity were absent in the HCC and peritumor liver tissues.Furthermore,4 common prognosis-associated genes(RHOB,TALDO1,HLA-DPA1,and TKT)were significantly overexpressed in the paired tumor tissue and blood.Conclusions:Our study revealed 5 specific subsets of NK cells in healthy human liver tissues.However,only 3 of the 5 NK cell subsets were present in HCC and peritumor tissues.The cytotoxic NK cell subsets were absent in HCC tissues.Furthermore,we identified 4 potential non-invasive prognostic biomarkers in patients with HCC.

Sliding Mode Control of Hydraulic Pressure in Electro-Hydraulic Brake System Based on the Linearization of Higher-Order Model

The possibility to enhance the stability and robustness of electrohydraulic brake(EHB)systems is considered a subject of great importance in the automotive field.In such a context,the present study focuses on an actuator with a four-way sliding valve and a hydraulic cylinder.A 4-order nonlinear mathematical model is introduced accordingly.Through the linearization of the feedback law of the high order EHB model,a sliding mode control method is proposed for the hydraulic pressure.The hydraulic pressure tracking controls are simulated and analyzed by MATLAB/Simulink soft considering separately different conditions,i.e.,a sine wave,a square wave and a square wave with superimposed sine disturbance.The results show that the proposed strategy can track the target within 0.25 s,and the mean observed error is less than 1.2 bar.Moreover,with such a strategy,faster response and less overshoot are possible,which should be regarded as significant advantages.

Structural effects of sulfonamides on the proliferation dynamics of sulfonamide resistance genes in the sequencing batch reactors and the mechanism

Antibiotic resistance genes(ARGs)can be easily promoted by antibiotics,however,the structural effects of antibiotics on the proliferation of ARGs dynamic and the associated mechanisms remain obscure in,especially,activated sludge sequencing batch reactors.In the present study,the effects of 9 sulfonamides(SAs)with different structures on the proliferation dynamic of sulfonamide resistance genes(Suls)in the activated sludge sequencing batch reactors and the corresponding mechanisms were determined(30 days),and the results showed that the largest proliferation value(ΔA^(R))of Suls dynamic for SAs(sulfachloropyridazine)was approximately 2.9 times than that of the smallest one(sulfadiazine).The proliferation of Suls was significantly related to the structural features(minHBint6,SssNH,SHBd and SpMax2_Bhm)that represent the biological activity of SAs.To interpret the phenomenon,a mechanistic model was developed and the results indicated that the biodegradation of SAs(T_(1/2))rather than conjugative transfer frequency or mutation frequency tends to be the key process for affecting Suls proliferation.T_(1/2)was proved to be dependent on the interactions between SAs and receptors(E_(binding)),the cleavage mode(bond dissociation energy),and the site of nucleophilic assault.Besides,the metagenomic analysis showed that SAs posed significant effect on antibiotic resistome and Tnp31 played a vital role in the proliferation of Suls.Overall,our findings provide important insight into a theoretical basis for understanding the structural effects of SAs on the proliferation of ARGs in SBR systems.

Biomimetic microchannel network with functional endothelium formed by sacrificial electrospun fibers inside 3D gelatin methacryloyl(GelMA)hydrogel models

Three-dimensional(3D)hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration.A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular function.This report describes the preparation of a biomimetic hydrogel scaffold with an internal microchannel network,using electrospinning techniques and the sacrificial template method for 3D cell culture.Microchannels and cavities were created within the gelatin methacryloyl(GelMA)hydrogel by sacrificing polyvinyl alcohol(PVA)electrospun fibers(>10µm),resulting in the creation of microvessel-like channels.Mechanical characterizations,swelling properties,and biodegradation analysis were conducted to investigate the feasibility of a biomimetic microchannel network hydrogel scaffold for 3D cell culture applications.Compared to pure GelMA hydrogel,the hydrogel with microchannels promoted cell proliferation,adhesion,and endothelial tube formation.Moreover,the results confirmed that the biomimetic microchannel network scaffold had a major impact on the distribution and arrangement of human umbilical vein endothelial cells(HUVECs)and can enable the formation of artificial microvasculature by the culture of HUVECs and cell media perfusion.

多级钯-铜-银多孔纳米花作为高效电催化剂催化CO_(2)还原为C_(2+)产物

近年来,具有可控元素分布的铜基多金属纳米晶作为CO_(2)还原反应(CO_(2)RR)的电催化剂,受到了广泛研究。通过对铜电催化剂进行二次甚至多次的金属元素修饰,能够有效改变其整体d带结构并引起d带中心的位移。这种变化可以影响铜对关键中间体的表面亲和力,从而影响后续的催化途径。除了调整电子结构,形貌工程也成为提高CO_(2)RR电催化性能的有效手段。相对于随机形状的球形颗粒,基于二维纳米片构建的三维多孔结构有利于最大限度地暴露表面原子,为催化过程中产生的关键中间体提供丰富的扩散通道和反应中心。然而,通过设计合成路线构建这种类型的纳米结构是一项技术挑战,传统的分步自组装策略耗时且难以精确控制结构。因此,我们的研究旨在实现高纯度的合成方法,制备这种独特的纳米结构,并精确调控元素组成和电子结构,以探索结构优势与CO_(2)RR电化学性能改善之间的潜在关系,具有重要的应用价值。在此研究中,我们合理设计了钯-铜-银(Pd-Cu-Ag)纳米晶的二维-三维杂化结构,实现了可控的合成过程,并验证了其在电化学CO_(2)还原中的应用潜力。合成过程中,通过使用封装剂十八烷基三甲基氯化铵,成功地将Au@Cu_(x)O纳米球转化为层状CuAg纳米花(HNFs)。有趣的是,该过程中原位形成了作为构建单元的纳米薄片。通过对CuAg HNFs与Na_(2)PdCl_(4)进行电偶置换,除去了Ag和Cu,引入了零价的Pd,并在纳米片上形成了大量孔隙。我们对这些CuAg电催化剂进行了CO_(2)RR测试,结果显示Pd_(0.7)Cu_(40.0)Ag_(59.7)PHNs在C_(2+)产物选择性(69.5%)和C_(2+)分电流密度(-349.1mA·cm^(-2))方面表现出最佳性能。密度泛函理论(DFT)模拟表明,PdAgCu表面具有独特的电子性质,降低了C-C偶联反应的能垒,凸显了Pd掺杂对CuAg电催化剂CO_(2)还原的卓越性能。本研究为基于多孔纳米薄片构建多层次多金属纳米结构提供了一种直观方法,并验证了其在电催化方面的结构优势,为高效的CO_(2)RR催化剂的合理设计提供了依据。

NK cell receptor imbalance and NK cell dysfunction in HBV nfection and hepatocellular carcinoma

Hepatocellular carcinoma （HCC） is currently the third leading cause of cancer mortality and a common poor-prognosis malignancy due to postoperative recurrence and metastasis. There is a significant correlation between chronic hepatitis B virus （HBV） infection and hepatocarcinogenesis. As the first line of host defense against viral infections and tumors, natural killer （NK） cells express a large number of immune recognition receptors （NK receptors （NKRs）） to recognize ligands on hepatocytes, liver sinusoidal endothelial cells, stellate cells and Kupffer cells, which maintain the balance between immune response and immune tolerance of NK cells. Unfortunately, the percentage and absolute number of liver NK cells decrease significantly during the development and progression of HCC. The abnormal expression of NK cell receptors and dysfunction of liver NK cells contribute to the progression of chronic HBV infection and HCC and are significantly associated with poor prognosis for liver cancer. In this review, we focus on the role of NK cell receptors in anti-tumor immune responses in HCC, particularly HBV-related HCC. We discuss specifically how tumor cells evade attack from NK cells and how emerging understanding of NKRs may aid the development of novel treatments for HCC. Novel mono- and combination therapeutic strategies that target the NK cell receptor-ligand system may potentially lead to successful and effective immunotherapy in HCC.

Tissue-resident lymphocytes: from adaptive to innate immunity

Efficient immune responses against invading pathogens often involve coordination between cells from both the innate and adaptive immune systems.For multiple decades,it has been believed that CD8+memory T cells and natural killer(NK)cells constantly and uniformly recirculate.Only recently was the existence of noncirculating memory T and NK cells that remain resident in the peripheral tissues,termed tissue-resident memory T(TRM)cells and tissue-resident NK(trNK)cells,observed in various organs owing to improved techniques.TRM cells populate a wide range of peripheral organs,including the skin,sensory ganglia,gut,lungs,brain,salivary glands,female reproductive tract,and others.Recent findings have demonstrated the existence of TRM in the secondary lymphoid organs(SLOs)as well,leading to revision of the classic theory that they exist only in peripheral organs.trNK cells have been identified in the uterus,skin,kidney,adipose tissue,and salivary glands.These tissue-resident lymphocytes do not recirculate in the blood or lymphatic system and often adopt a unique phenotype that is distinct from those of circulating immune cells.In this review,we will discuss the recent findings on the tissue residency of both innate and adaptive lymphocytes,with a particular focus on CD8+memory T cells,and describe some advances regarding unconventional T cells(invariant NKT cells,mucosal-associated invariant T cells(MAIT),andγδT cells)and the emerging family of trNK cells.Specifically,we will focus on the phenotypes and functions of these subsets and discuss their implications in anti-viral and anti-tumor immunity.

Natural killer cells in liver diseases

The liver has been characterized as a frontline lymphoid organ with complex immunological features such as liver immunity and liver tolerance. Liver tolerance plays an important role in liver diseases including acute inflammation, chronic infection, autoimmune disease, and tumors. The liver contains a large proportion of natural killer （NK） cells, which exhibit heterogeneity in phenotypic and functional characteristics. NK cell activation, well known for its role in the immune surveillance against tumor and pathogen-infected cells, depends on the balance between numerous activating and inhibitory signals. In addition to the innate direct ＂killer＂ functions, NK cell activity contributes to regulate innate and adaptive immunity （helper or regulator）. Under the setting of liver diseases, NK cells are of great importance for stimulating or inhibiting immune responses, leading to either immune activation or immune tolerance. Here, we focus on the relationship between NK cell biology, such as their phenotypic features and functional diversity, and liver diseases.

All-trans retinoic acid induces leukemia resistance to NK cell cytotoxicity by down-regulating B7-H6 expression via c-Myc signaling

Background:The interaction between activating receptor NKp30 and its major tumor ligand B7-H6 is important for NK cell-mediated tumor rejection.However,the regulation of B7-H6 by tumor therapeutics remains largely unknown.In this study,we investigated the regulation of B7-H6 by all-trans retinoic acid(atRA),a terminal differentiation inducer of tumor cells that is extensively used for clinical leukemia therapy.Methods:We investigated the role of NKp30:B7-H6 axis in NK cell-mediated tumor lysis against leukemia cells and the influence of atRA treatment on the cytotoxicity of NK cells using NK cell lines(NK92 and NKG)and leukemia cell lines(U-937 and THP-1).We evaluated the effect of atRA treatment on the expression of B7-H6 using real-time PCR,flow cytometry and western blotting.We used CRISPR/Cas9 to knockdown B7-H6 expression and siRNA to knockdown c-Myc in U-937 cells to evaluate the role of B7-H6 and c-Myc in atRA-induced tumor resistance against NK cells.Results:NK cell-mediated U-937 cell lysis was mainly dependent on NKp30/B7-H6 interaction.Blockade of B7-H6 by monoclonal antibody significantly impaired NK cytotoxicity.atRA treatment induced U-937 resistance to NK cell cytotoxicity by reducing B7-H6 expression,and showed no effect on NK cytotoxicity against B7-H6 knockdown U-937 cells.Epigenetic modifications,such as DNA methylation and histone deacetylase(HDAC),were not responsible for atRA-mediated B7-H6 down-regulation as inhibitors of these pathways could not restore B7-H6 mRNA expression.On the other hand,atRA treatment reduced c-Myc expression,which in turn inhibited the transcription of B7-H6 on leukemia cells.Conclusion:atRA treatment promotes tumor cell resistance against NK cellmediated lysis by down-regulating B7-H6 expression via the c-Myc signaling pathway,suggesting that more attention needs to be paid to the immunological adverse effects in the clinical use of atRA treatment.

Single-cell analysis reveals the origins and intrahepatic development of liver-resident IFN-γ-producing γδ T cells

γδ T cells are heterogeneous lymphocytes located in various tissues.However,a systematic and comprehensive understanding of the origins of γδ T cell heterogeneity and the extrathymic developmental pathway associated with liver γδ T cells remain largely unsolved.In this study,we performed single-cell RNA sequencing(scRNA-seq)to comprehensively catalog the heterogeneity of γδ T cells derived from murine liver and thymus samples.We revealed the developmental trajectory of γδ T cells and found that the liver contains γδ T cell precursors(pre-γδ T cells).The developmental potential of hepatic γδ T precursor cells was confirmed through in vitro coculture experiments and in vivo adoptive transfer experiments.The adoptive transfer of hematopoietic progenitor Lin^(-)Sca-1^(+)Mac-1^(+)(LSM)cells from fetal or adult liver samples to sublethally irradiated recipients resulted in the differentiation of liver LSM cells into pre-γδ T cells and interferon-gamma^(+)(IFN-γ^(+))but not interleukin-17a^(+)(IL-17a^(+))γδ T cells in the liver.Importantly,thymectomized mouse models showed that IFN-γ-producing γδ T cells could originate from liver LSM cells in a thymus-independent manner.These results suggested that liver hematopoietic progenitor LSM cells were able to differentiate into pre-γδ T cells and functionally mature γδ T cells,which implied that these cells are involved in a distinct developmental pathway independent of thymus-derived γδ T cells.

Preferential Formation of Ethylene via Electrocatalytic CO_(2) Reduction on Mesoporous Cu_(2)O Nanoparticles:Synergistic Effects of Pore Structure Confinement and Surface Amine

We present a facile synthetic strategy to create mesoporous Cu_(2)O nanocrystals with tunable pore structures and surface functional groups of amine derivatives for efficient and preferable electrochemical conversion of CO_(2) into ethylene.The structural characteristics of theseCu_(2)O nanocrystals can be manipulated using a set of amine derivatives,such as pyridine,4,4'-bipyridine,and hexamethylenetetramine,during the oxidative etching process of Cu nanocrystals by bubbling gaseous oxygen in N,N-dimethylformamide solution.These amine derivatives not only serve as surface functional groups but also significantly affect the resulting pore structures.The synergistic effect of pore structure confinement and surface amine functionalization leads to the superb Faradaic efficiency(FE)of 51.9% for C_(2)H_(4),respectively,together with the C_(2)H_(4) partial current density of -209.4 mA·cm^(-2) at -0.8 V vs.reversible hydrogen electrode(RHE).The relatively high selectivity towards C_(2)H_(4) was investigated using DFT simulations,where 4,4'-bipyridine functionalized Cu_(2)O seemed to favor the C_(2)H_(4) formation with the low free energy of the intermediates.This study provides a feasible strategy to manipulate the pore structure and surface functionalization of mesoporous Cu_(2)O nanocrystals by regulating the oxidative etching process,which sheds light on the rational preparation of high-performance CO_(2)RR electrocatalysts.