Monitoring specific immune cells in vivo will provide significant information for improving the therapeutic effect of immunotherapy. Herein, the in vivo two-color fluorescence molecular imaging of an ...important immune cell, myeloid-derived suppressor cell (MDSC), was realized by using quantum dot (QD)-based nanoprobes with non-overlap emission in the second near-infrared window (NIR-II, 1000–1700 nm). NIR-IIa and NIR-IIb QDs were conjugated with two MDSC-specific antibodies, respectively, and targeted the in vivo MDSCs together. Due to the suppressed photon scattering and diminished autofluorescence in the NIR-II window, the distribution of MDSCs in different organs and tissues was clearly revealed in a non-invasive way by the colocalization of two-color fluorescence from nanoprobes. The high-resolution imaging further confirmed the exact distribution of MDSCs in tumor immune microenvironment (TIME). Our results demonstrated that NIR-II fluorescence nanoprobes with molecular targeting ability provided a powerful tool for monitoring the dynamic change of immune cell populations in TIME in vivo, thus guiding the choice of clinical medicine and evaluating the therapeutic effect.
NLRP3 inflammasome acts as a danger signal sensor that triggers and coordinates the inflammatory response. However, the roles of NLRP3 inflammasome in the tumorigenesis and development of cancer stem ...cells (CSCs) of squamous cell carcinoma of the head and neck (SCCHN) remain ambiguous.
In our study, tissue microarrays, ELISA, sphere-forming assay, colony formation assay and Western blot analysis were performed to evaluate the effect of NLRP3 inflammasome on the development of CSCs in human SCCHN tissue specimen, cell lines, and transgenic mouse SCCHN model.
The components of NLRP3 inflammasome, namely, NLRP3, ASC, Caspase-1, and IL-18 were correlated with CSCs markers BMI1, ALDH1 and CD44 in human SCCHN specimens. Moreover, NLRP3, Caspase-1, IL-1β, and IL-18 were highly expressed in SCCHN cell lines. NLRP3 inflammasome activated by LPS and ATP promoted sphere-forming and colony formation capacities along with an upregulation of BMI1, ALDH1 and CD44. In addition, NLRP3 inflammasome blockade by NLRP3 inhibitor MCC950 reduced sphere and colony number, also decreased the expression of BMI1, ALDH1 and CD44 in SCCHN cell lines. Expression of NLRP3, ASC, Caspase-1, IL-1β, IL-18, BMI1, ALDH1 and CD44 was upregulated in Tgfbr1/Pten 2cKO mouse SCCHN model, and NLRP3 inflammasome expression was closely related to those CSCs makers in mice SCCHN. However, MCC950 treatment reduced the expression of NLRP3 inflammasome, CSCs markers BMI1, ALDH1 and CD44 in Tgfbr1/Pten 2cKO mice SCCHN. In addition, blockade of NLRP3 inflammasome can also delayed the tumor-burdened speed in SCCHN mice.
Our study demonstrates that NLRP3 inflammasome was upregulated and associated with the carcinogenesis and CSCs self-renewal activation in SCCHN. NLRP3 inflammasome can be a potential target in the development of novel approaches for head and neck squamous cell carcinoma therapy.
The nitrate electroreduction reaction (NO3 –-ERR) is an efficient and green approach for nitrate remediation, which requires a highly active and selective electrocatalyst. In this work, porous and ...amorphous cobalt phosphide nanoshuttles (CoP PANSs) are successfully synthesized by using Mg2+ ion-doped calcium carbonate nanoshuttles (Mg-CaCO3 NSs) as the initial reaction precursor via precipitation transformation and a high-temperature phosphidation strategy. Various physical characterizations show that CoP PANSs have porous architecture, amorphous crystal structure, and big surface area. Electrochemical measurements reveal for the first time that CoP PANSs have outstanding electroactivity for NO3 –-ERR in a neutral electrolyte. At an applied potential of −0.5 V vs reversible hydrogen electrode, CoP PANSs can achieve a high Faraday efficiency (94.24 ± 2.8%) and high yield rate (19.28 ± 0.53 mg h–1 mgcat –1) for ammonia production, which exceeds most reported values at various electrocatalysts for NO3 –-ERR. Thus, the present result indicates that cobalt phosphide nanomaterials have promising application for NO3 –-ERR.
Xanthomonas campestris pv. campestris (Xcc) controls virulence and plant infection mechanisms via the activity of the sensor kinase and response regulator pair HpaS/hypersensitive response and ...pathogenicity G (HrpG). Detailed analysis of the regulatory role of HpaS has suggested the occurrence of further regulators besides HrpG. Here we used in vitro and in vivo approaches to identify the orphan response regulator VemR as another partner of HpaS and to characterize relevant interactions between components of this signalling system. Bacterial two‐hybrid and protein pull‐down assays revealed that HpaS physically interacts with VemR. Phos‐tag SDS‐PAGE analysis showed that mutation in hpaS reduced markedly the phosphorylation of VemR in vivo. Mutation analysis reveals that HpaS and VemR contribute to the regulation of motility and this relationship appears to be epistatic. Additionally, we show that VemR control of Xcc motility is due in part to its ability to interact and bind to the flagellum rotor protein FliM. Taken together, the findings describe the unrecognized regulatory role of sensor kinase HpaS and orphan response regulator VemR in the control of motility in Xcc and contribute to the understanding of the complex regulatory mechanisms used by Xcc during plant infection.
Sensor kinase HpaS regulates T3SS and swimming motility by controlling the phosphorylation of response regulators HrpG and VemR, respectively.
Vortex-induced vibration (VIV) exists widely in natural and industrial fields. The main approaches for solving VIV problems are numerical simulations and experimental methods. However, experiment ...methods are difficult to obtain the whole flow field information and also high-cost while numerical simulation is extraordinary time-consuming and limited in low Reynolds number and simple geometric configuration. In addition, numerical simulations are difficult to handle the moving mesh technique. In this paper, physics informed neural network (PINN) is utilized to solve the VIV and wake-induced vibration (WIV) of cylinder with different reduced velocities. Compared to tradition data-driven neural network, the Reynolds Average Navier-Stokes (RANS) equation, by implanting an additional turbulent eddy viscosity, coupled with structure's dynamic motion equation are also embedded into the loss function. Training and validation data is obtained by computational fluid dynamic (CFD) technique. Three scenarios are proposed to validate the performance of PINN in solving VIV and WIV of cylinders. In the first place, the stiffness parameter and damping parameter are calculated via limited force data and displacement data; secondly, the turbulence flow field and lifting force/drag force are inferred by scattered velocity information; eventually, the displacement can be directly predicted only through lifting forces and drag forces based on LSTM. Results demonstrate that, compared with traditional neural network, PINN method is more effective in inferring and re-constructing the unknown parameters and flow field with different Reynolds numbers under VIV and WIV circumstances.
•The RANS model is embedded into the PINN to calculate the VIV and WIV.•The PINN method is utilized to construct the whole fluid flow.•The eddy viscosity is inferred by PINN.•The trajectories of cylinders can be directly inferred by PINN.
Signal transduction pathways mediated by sensor histidine kinases and cognate response regulators control a variety of physiological processes in response to environmental conditions in most ...bacteria. Comparatively little is known about the mechanism(s) by which single‐domain response regulators (SD‐RRs), which lack a dedicated output domain but harbour a phosphoryl receiver domain, exert their various regulatory effects in bacteria. Here we have examined the role of the SD‐RR proteins encoded by the phytopathogen Xanthomonas campestris pv. campestris (Xcc). We describe the identification and characterization of a SD‐RR protein named McvR (motility, chemotaxis, and virulence‐related response regulator) that is required for virulence and motility regulation in Xcc. Deletion of the mcvR open reading frame caused reduced motility, chemotactic movement, and virulence in Xcc. Global transcriptome analyses revealed the McvR had a broad regulatory role and that most motility and pathogenicity genes were down‐regulated in the mcvR mutant. Bacterial two‐hybrid and protein pull‐down assays revealed that McvR did not physically interact with components of the bacterial flagellum but interacts with other SD‐RR proteins (like CheY) and the subset of DNA‐binding proteins involved in gene regulation. Site‐directed mutagenesis and phosphor‐transfer experiments revealed that the aspartyl residue at position 55 of the receiver domain is important for phosphorylation and the regulatory activity of McvR protein. Taken together, the findings describe a previously unrecognized class of SD‐RR protein that contributes to the regulation of motility and virulence in Xcc.
McvR modulates cell motility via interacting with CheY protein and indirectly regulating the expression of a series of motility‐related genes.
Ferroptosis has been defined as a novel form of regulated cell death characterized by iron-dependent lipid peroxidation. Manganese has been used to induce ferroptosis in cancer cells recently. This ...study aims to investigate whether manganese can induce ferroptosis in oral squamous cell carcinoma (OSCC) and the underlying biological mechanisms.
Cancer cells with or without manganese treatment were analyzed by RNA-sequencing to identify ferroptosis-related genes. Next, the activation of YAP/TAZ/ACSL4-ferroptosis signaling pathway was detected. Bioinformatic analysis and immunofluorescence assay were used to explore the phase separation of YAP/TAZ. Finally, specimens of OSCC patients were applied to analyze the clinical significance of YAP/TAZ/ACSL4.
RNA-sequencing analysis showed the ferroptosis-related genes and YAP/TAZ were upregulated after manganese treatment. The results of immunofluorescence, ELISA, western blotting, etc. further confirmed that manganese-induced ferroptosis depends on YAP/TAZ/ACSL4 signaling pathway. Moreover, the activation of ACSL4 was achieved by YAP/TAZ phase separation. The survival analysis in OSCC specimen suggested that the higher level of YAP/TAZ-ACSL4 axis expression indicates longer survival.
Manganese induces YAP/TAZ phase separation and subsequent ACSL4 activation via YAP/TAZ nuclear translocation, which facilitates ferroptosis of OSCC. Then YAP/TAZ-ACSL4 axis can be used as a potential prognostic predictor of OSCC patients.
The bacterial phytopathogen Xanthomonas campestris pv. campestris (Xcc) relies on the hrp (hypersensitive response and pathogenicity) genes to cause disease and induce hypersensitive response (HR). ...The hrp genes of bacterial phytopathogens are divided into two groups. Xcc hrp genes belong to group II. It has long been known that the group II hrp genes are activated by an AraC‐type transcriptional regulator whose expression is controlled by a two‐component system (TCS) response regulator (named HrpG in Xcc). However, no cognate sensor kinase has yet been identified. Here, we present evidence showing that the Xcc open‐reading frame XC_3670 encodes a TCS sensor kinase (named HpaS). Mutation of hpaS almost completely abolished the HR induction and virulence. Bacterial two‐hybrid and protein pull‐down assays revealed that HpaS physically interacted with HrpG. Phos‐tag™ SDS‐PAGE analysis showed that mutation in hpaS reduced markedly the phosphorylation of HrpG in vivo. These data suggest that HpaS and HrpG are most likely to form a TCS. We also showed that XC_3669 (named hpaR2), which is adjacent to hpaS and encodes a putative TCS response regulator, is required for full virulence but not HR induction. HpaR2 also physically interacted with HpaS, suggesting that HpaS may also form another TCS with HpaR2.
Due to high mortality rates and poor prognosis, liver injury remains one of the leading causes of mortality worldwide. Amounting evidence suggested that the activation of the nucleotide-binding ...oligomerization domain (NOD)-like receptor containing pyrin domain 3 (NLRP3) inflammasome, which promotes pro-interleukin-1β (pro-IL-1β) and pro-interleukin-18 (pro-IL-18) cleavage and maturation play a vital role in the occurrence and development of liver injury and liver disease. Mitochondrial dysfunction is a common co-occurring event in liver injury. Abnormal mitochondrial function has also been shown to be closely related to NLRP3 inflammasome activation. Currently, natural products have attracted the attention of researchers as potential therapeutic agents for liver injury and liver disease due to their less toxicity and multi-targeting advantages. A number of natural products have been discovered to prevent and treat liver injury by modulating the activation of NLRP3 inflammasome. In this review, we highlight the mechanisms involved in the regulation of NLRP3 inflammasome activation by mitochondria during liver injury and natural products that target mitochondrial function processes to prevent or treat liver injury. Our paper may shed insight into novel viewpoint and target for prevention and treatment of liver injury based on NLRP3 inflammasome.
Display omitted
•NLRP3 inflammasome activation regulated by mitochondria is involved in liver injury.•Natural products target NLRP3 inflammasome activation by mitochondria.•The crosstalk between mitochondria and NLRP3 inflammasome deserves investigation.
Summary
The ability of the bacterial phytopathogen Xanthomonas campestris pv. campestris (Xcc) to cause disease is dependent on the type III secretion system (T3SS). Proteins of the Xcc T3SS are ...encoded by hrp (hypersensitive response and pathogenicity) genes and whose expression is mainly controlled by the regulators HrpG and HrpX. Here, we describe the identification and characterization of a previously unknown regulatory protein (named HpaP), which plays important role in hrp gene expression and virulence in Xcc. Clean deletion of hpaP demonstrated reduced virulence and HR (hypersensitive response) induction of Xcc and alterations in cell motility and stress tolerance. Global transcriptome analyses revealed that most hrp genes were down regulated in the hpaP mutant, suggesting HpaP positively regulates hrp genes. GUS activity assays implied that HpaP regulates the expression of hrp genes via controlling the expression of hrpX. Biochemical analyses revealed that HpaP protein had both ATPase and phosphatase activity. While further site‐directed mutagenesis of conserved residues in the PTP loop (a protein tyrosine phosphatase signature) of HpaP resulted in the loss of both phosphatase activity and regulatory activity in virulence and HR. Taken together, the findings identify a new regulatory protein that controls hrp gene expression and virulence in Xcc.
PDF
