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1.
Nat Immunol ; 19(6): 547-560, 2018 06.
Article in English | MEDLINE | ID: mdl-29777223

ABSTRACT

The adaptor CARD9 functions downstream of C-type lectin receptors (CLRs) for the sensing of microbial infection, which leads to responses by the TH1 and TH17 subsets of helper T cells. The single-nucleotide polymorphism rs4077515 at CARD9 in the human genome, which results in the substitution S12N (CARD9S12N), is associated with several autoimmune diseases. However, the function of CARD9S12N has remained unknown. Here we generated CARD9S12N knock-in mice and found that CARD9S12N facilitated the induction of type 2 immune responses after engagement of CLRs. Mechanistically, CARD9S12N mediated CLR-induced activation of the non-canonical transcription factor NF-κB subunit RelB, which initiated production of the cytokine IL-5 in alveolar macrophages for the recruitment of eosinophils to drive TH2 cell-mediated allergic responses. We identified the homozygous CARD9 mutation encoding S12N in patients with allergic bronchopulmonary aspergillosis and revealed activation of RelB and production of IL-5 in peripheral blood mononuclear cells from these patients. Our study provides genetic and functional evidence demonstrating that CARD9S12N can turn alveolar macrophages into IL-5-producing cells and facilitates TH2 cell-mediated pathologic responses.


Subject(s)
Aspergillosis, Allergic Bronchopulmonary/immunology , CARD Signaling Adaptor Proteins/immunology , Interleukin-5/biosynthesis , Macrophages, Alveolar/immunology , Th2 Cells/immunology , Animals , Aspergillosis, Allergic Bronchopulmonary/genetics , CARD Signaling Adaptor Proteins/genetics , Humans , Interleukin-5/immunology , Macrophages, Alveolar/metabolism , Mice , Polymorphism, Single Nucleotide , Signal Transduction/immunology
2.
Nat Immunol ; 16(6): 642-52, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25915733

ABSTRACT

Fungal infection stimulates the canonical C-type lectin receptor (CLR) signaling pathway via activation of the tyrosine kinase Syk. Here we identify a crucial role for the tyrosine phosphatase SHP-2 in mediating CLR-induced activation of Syk. Ablation of the gene encoding SHP-2 (Ptpn11; called 'Shp-2' here) in dendritic cells (DCs) and macrophages impaired Syk-mediated signaling and abrogated the expression of genes encoding pro-inflammatory molecules following fungal stimulation. Mechanistically, SHP-2 operated as a scaffold, facilitating the recruitment of Syk to the CLR dectin-1 or the adaptor FcRγ, through its N-SH2 domain and a previously unrecognized carboxy-terminal immunoreceptor tyrosine-based activation motif (ITAM). We found that DC-derived SHP-2 was crucial for the induction of interleukin 1ß (IL-1ß), IL-6 and IL-23 and anti-fungal responses of the TH17 subset of helper T cells in controlling infection with Candida albicans. Together our data reveal a mechanism by which SHP-2 mediates the activation of Syk in response to fungal infection.


Subject(s)
Candidiasis/immunology , Dendritic Cells/physiology , Intracellular Signaling Peptides and Proteins/metabolism , Macrophages/physiology , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Protein-Tyrosine Kinases/metabolism , T-Lymphocytes, Helper-Inducer/immunology , Th17 Cells/immunology , Amino Acid Motifs/genetics , Animals , Antigens, Fungal/immunology , Cells, Cultured , Cytokines/metabolism , Enzyme Activation , Inflammation Mediators/metabolism , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Lymphocyte Activation , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Mutation/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Receptors, IgE/genetics , Receptors, IgE/metabolism , Signal Transduction , Syk Kinase
3.
J Immunol ; 213(3): 347-361, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38847616

ABSTRACT

The cyclic GMP-AMP synthase (cGAS)-stimulator of IFN genes (STING) pathway is instrumental to antitumor immunity, yet the underlying molecular and cellular mechanisms are complex and still unfolding. A new paradigm suggests that cancer cells' cGAS-synthesized cGAMP can be transferred to tumor-infiltrating immune cells, eliciting STING-dependent IFN-ß response for antitumor immunity. Nevertheless, how the tumor microenvironment may shape this process remains unclear. In this study, we found that extracellular ATP, an immune regulatory molecule widely present in the tumor microenvironment, can potentiate cGAMP transfer, thereby boosting the STING signaling and IFN-ß response in murine macrophages and fibroblasts. Notably, genetic ablation or chemical inhibition of murine volume-regulation anion channel LRRC8/volume-regulated anion channel (VRAC), a recently identified cGAMP transporter, abolished ATP-potentiated cGAMP transfer and STING-dependent IFN-ß response, revealing a crucial role of LRRC8/VRAC in the cross-talk of extracellular ATP and cGAMP. Mechanistically, ATP activation of the P2X family receptors triggered Ca2+ influx and K+ efflux, promoting reactive oxygen species production. Moreover, ATP-evoked K+ efflux alleviated the phosphorylation of VRAC's obligate subunit LRRC8A/SWELL1 on S174. Mutagenesis studies indicated that the phosphorylation of S174 on LRRC8A could act as a checkpoint for VRAC in the steady state and a rheostat of ATP responsiveness. In an MC38-transplanted tumor model, systemically blocking CD39 and ENPP1, hydroxylases of extracellular ATP and cGAMP, respectively, elevated antitumor NK, NKT, and CD8+ T cell responses and restrained tumor growth in mice. Altogether, this study establishes a crucial role of ATP in facilitating LRRC8/VRAC transport cGAMP in the tumor microenvironment and provides new insight into harnessing cGAMP transfer for antitumor immunity.


Subject(s)
Adenosine Triphosphate , Membrane Proteins , Nucleotides, Cyclic , Tumor Microenvironment , Animals , Nucleotides, Cyclic/metabolism , Mice , Adenosine Triphosphate/metabolism , Membrane Proteins/metabolism , Membrane Proteins/immunology , Tumor Microenvironment/immunology , Interferon-beta/metabolism , Interferon-beta/immunology , Mice, Inbred C57BL , Humans , Signal Transduction/immunology , Mice, Knockout , Cell Line, Tumor , Cations/metabolism , Neoplasms/immunology , Neoplasms/metabolism , Nucleotidyltransferases/metabolism , Macrophages/immunology , Macrophages/metabolism
4.
Eur Respir J ; 63(5)2024 May.
Article in English | MEDLINE | ID: mdl-38514095

ABSTRACT

INTRODUCTION: Patients with allergic bronchopulmonary aspergillosis (ABPA) suffer from repeated exacerbations. The involvement of T-cell subsets remains unclear. METHODS: We enrolled ABPA patients, asthma patients and healthy controls. T-helper type 1 (Th1), 2 (Th2) and 17 (Th17) cells, regulatory T-cells (Treg) and interleukin (IL)-21+CD4+T-cells in total or sorted subsets of peripheral blood mononuclear cells and ABPA bronchoalveolar lavage fluid (BALF) were analysed using flow cytometry. RNA sequencing of subsets of CD4+T-cells was done in exacerbated ABPA patients and healthy controls. Antibodies of T-/B-cell co-cultures in vitro were measured. RESULTS: ABPA patients had increased Th2 cells, similar numbers of Treg cells and decreased circulating Th1 and Th17 cells. IL-5+IL-13+IL-21+CD4+T-cells were rarely detected in healthy controls, but significantly elevated in the blood of ABPA patients, especially the exacerbated ones. We found that IL-5+IL-13+IL-21+CD4+T-cells were mainly peripheral T-helper (Tph) cells (PD-1+CXCR5-), which also presented in the BALF of ABPA patients. The proportions of circulating Tph cells were similar among ABPA patients, asthma patients and healthy controls, while IL-5+IL-13+IL-21+ Tph cells significantly increased in ABPA patients. Transcriptome data showed that Tph cells of ABPA patients were Th2-skewed and exhibited signatures of follicular T-helper cells. When co-cultured in vitro, Tph cells of ABPA patients induced the differentiation of autologous B-cells into plasmablasts and significantly enhanced the production of IgE. CONCLUSION: We identified a distinctly elevated population of circulating Th2-skewed Tph cells that induced the production of IgE in ABPA patients. It may be a biomarker and therapeutic target for ABPA.


Subject(s)
Aspergillosis, Allergic Bronchopulmonary , B-Lymphocytes , Bronchoalveolar Lavage Fluid , Th2 Cells , Humans , Male , Female , Aspergillosis, Allergic Bronchopulmonary/immunology , Adult , Th2 Cells/immunology , Middle Aged , Case-Control Studies , B-Lymphocytes/immunology , Bronchoalveolar Lavage Fluid/immunology , Bronchoalveolar Lavage Fluid/cytology , T-Lymphocytes, Regulatory/immunology , Asthma/immunology , Th17 Cells/immunology , T-Lymphocytes, Helper-Inducer/immunology
5.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Article in English | MEDLINE | ID: mdl-34301894

ABSTRACT

Opportunistic fungal infections have become one of the leading causes of death among immunocompromised patients, resulting in an estimated 1.5 million deaths each year worldwide. The molecular mechanisms that promote host defense against fungal infections remain elusive. Here, we find that Myosin IF (MYO1F), an unconventional myosin, promotes the expression of genes that are critical for antifungal innate immune signaling and proinflammatory responses. Mechanistically, MYO1F is required for dectin-induced α-tubulin acetylation, acting as an adaptor that recruits both the adaptor AP2A1 and α-tubulin N-acetyltransferase 1 to α-tubulin; in turn, these events control the membrane-to-cytoplasm trafficking of spleen tyrosine kinase and caspase recruitment domain-containing protein 9 Myo1f-deficient mice are more susceptible than their wild-type counterparts to the lethal sequelae of systemic infection with Candida albicans Notably, administration of Sirt2 deacetylase inhibitors, namely AGK2, AK-1, or AK-7, significantly increases the dectin-induced expression of proinflammatory genes in mouse bone marrow-derived macrophages and microglia, thereby protecting mice from both systemic and central nervous system C. albicans infections. AGK2 also promotes proinflammatory gene expression in human peripheral blood mononuclear cells after Dectin stimulation. Taken together, our findings describe a key role for MYO1F in promoting antifungal immunity by regulating the acetylation of α-tubulin and microtubules, and our findings suggest that Sirt2 deacetylase inhibitors may be developed as potential drugs for the treatment of fungal infections.


Subject(s)
Candida albicans/physiology , Candidiasis/immunology , Immunity, Innate/immunology , Leukocytes, Mononuclear/immunology , Microtubules/immunology , Myosin Type I/metabolism , Myosin Type I/physiology , Acetylation , Animals , Antifungal Agents/pharmacology , Candidiasis/drug therapy , Candidiasis/metabolism , Candidiasis/microbiology , Humans , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/microbiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Microtubules/drug effects , Microtubules/metabolism , Microtubules/microbiology , Myosin Type I/genetics , Signal Transduction
6.
Environ Geochem Health ; 46(6): 179, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38695935

ABSTRACT

The uncertainty in the generation and formation of non-point source pollution makes it challenging to monitor and control this type of pollution. The SWAT model is frequently used to simulate non-point source pollution in watersheds and is mainly applied to natural watersheds that are less affected by human activities. This study focuses on the Duliujian River Basin (Xiqing section), which is characterized by a dense population and rapid urbanization. Based on the calibrated SWAT model, this study analyzed the effects of land use change on non-point source pollution both temporally and spatially. It was found that nitrogen and phosphorus non-point source pollution load losses were closely related to land use type, with agricultural land and high-density urban land (including rural settlements) being the main contributors to riverine nitrogen and phosphorus pollution. This indicates the necessity of analyzing the impact of land use changes on non-point source pollution loads by identifying critical source areas and altering the land use types that contribute heavily to pollution in these areas. The simulation results of land use type changes in these critical source areas showed that the reduction effect on non-point source pollution load is in the order of forest land > grassland > low-density residential area. To effectively curb surface source pollution in the study area, strategies such as modifying urban land use types, increasing vegetation cover and ground infiltration rate, and strictly controlling the discharge of domestic waste and sewage from urban areas can be implemented.


Subject(s)
Environmental Monitoring , Nitrogen , Phosphorus , Rivers , Water Pollutants, Chemical , Rivers/chemistry , Phosphorus/analysis , Nitrogen/analysis , China , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Urbanization , Non-Point Source Pollution/analysis , Non-Point Source Pollution/prevention & control , Models, Theoretical , Agriculture , Computer Simulation
7.
J Immunol ; 206(9): 2061-2074, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33827893

ABSTRACT

The recently identified anion channel LRRC8 volume-regulated anion channels (VRACs) are heteromeric hexamers constituted with the obligate LRRC8A subunit paired with at least one of the accessory LRRC8B to LRRC8E subunits. In addition to transport chloride, taurine, and glutamate, LRRC8 VRACs also transport the anticancer agent cisplatin and STING agonists 2'3'-cyclic GMP-AMP (cGAMP) and cyclic dinucleotides; hence, they are implicated in a variety of physiological and pathological processes, such as cell swelling, stroke, cancer, and viral infection. Although the subunit composition largely determines VRAC substrate specificity, the opening of various VRAC pores under physiological and pathological settings remains enigmatic. In this study, we demonstrated that VRACs comprising LRRC8A and LRRC8E (LRRC8A/E-containing VRACs), specialized in cGAMP transport, can be opened by a protein component present in serum under resting condition. Serum depletion ablated the tonic activity of LRRC8A/E-containing VRACs, decreasing cGAMP transport in various human and murine cells. Also, heating or proteinase K treatment abolished the ability of serum to activate VRAC. Genetic analyses revealed a crucial role for cGAMP synthase (cGAS) in serum/TNF-promoted VRAC activation. Notably, the presence of cGAS on the plasma membrane, rather than its DNA-binding or enzymatic activity, enabled VRAC activation. Moreover, phospholipid PIP2 seemed to be instrumental in the membrane localization of cGAS and its association with VRACs. Corroborating a role for LRRC8A/D-containing VRACs in cisplatin transport, serum and TNF markedly potentiated cisplatin uptake and killing of cancer cells derived from human or mouse. Together, these observations provide new insights into the complex regulation of VRAC activation and suggest a novel approach to enhance the efficacy of cGAMP and cisplatin in treating infection and cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , Inflammation/drug therapy , Membrane Proteins/immunology , Nucleotides, Cyclic/pharmacology , Animals , Antineoplastic Agents/immunology , Cisplatin/immunology , Inflammation/immunology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nucleotides, Cyclic/immunology
8.
Biomed Chromatogr ; 37(9): e5682, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37158044

ABSTRACT

Isodon excisoides (Y.Z.Sun ex C.H.Hu) H. Hara has been often used to treat liver diseases in folk medicine. However, the potential hepatoprotective mechanism of I. excisoides remains unclear. In this study, the mechanism of I. excisoides in alleviating drug-induced liver injury (DILI) was explored using a strategy combining metabolomics with network pharmacology for the first time. First, serum metabolomics was applied to identify differential metabolites and enrich metabolic pathways. The potential targets of I. excisoides for the treatment of DILI were investigated by network pharmacology. Subsequently, a comprehensive network of network pharmacology and metabolomics was established to find the key genes. Finally, molecular docking technology was used to further verify the key targets. As a result, four key genes including TYMS, IMPDH2, DHODH, and ASAH1 were identified. The proteins produced by these genes had high affinity with the corresponding diterpenoids. These results indicate that the components of I. excisoides play a liver-protective role by affecting the aforesaid key genes and key proteins. Our results offer a novel strategy for determining the pharmacological effects and potential targets of natural compounds.

9.
Immunity ; 39(2): 324-34, 2013 Aug 22.
Article in English | MEDLINE | ID: mdl-23911656

ABSTRACT

C-type lectin receptors (CLRs) play critical roles as pattern-recognition receptors (PRRs) for sensing Candida albicans infection, which can be life-threatening for immunocompromised individuals. Here we have shown that Dectin-3 (also called CLECSF8, MCL, or Clec4d), a previously uncharacterized CLR, recognized α-mannans on the surfaces of C. albicans hyphae and induced NF-κB activation. Mice with either blockade or genetically deleted Dectin-3 were highly susceptible to C. albicans infection. Dectin-3 constantly formed heterodimers with Dectin-2, a well-characterized CLR, for recognizing C. albicans hyphae. Compared to their respective homodimers, Dectin-3 and Dectin-2 heterodimers bound α-mannans more effectively, leading to potent inflammatory responses against fungal infections. Together, our study demonstrates that Dectin-3 forms a heterodimeric PRR with Dectin-2 for sensing fungal infection and suggests that different CLRs may form different hetero- and homodimers, which provide different sensitivity and diversity for host cells to detect various microbial infections.


Subject(s)
Candida albicans/immunology , Candidiasis/immunology , Lectins, C-Type/metabolism , Membrane Proteins/metabolism , Animals , Enzyme Activation , Female , Humans , Hyphae/immunology , Hyphae/metabolism , Lectins, C-Type/deficiency , Lectins, C-Type/genetics , Mannans/metabolism , Membrane Proteins/deficiency , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Transgenic , NF-kappa B/metabolism , Receptors, Pattern Recognition/immunology , Signal Transduction
10.
Chem Biodivers ; 19(12): e202200748, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36369642

ABSTRACT

Tyrosinase inhibitors can alleviate the harm to the liver caused by tyrosinase. How to effectively screen out natural tyrosinase inhibitors becomes a focus. In this study, Isodon excisoides was first extracted with the ultrasound optimized by response surface methodology. Then, a method combined ultrafiltration with ultra-liquid chromatography mass spectrometry (UHPLC/MS) was built to screen and identify tyrosinase inhibitors. The binding energies of active ingredients to tyrosinase were calculated by molecular docking. The reliability of the results was validated by the IC50 of enzyme inhibition assay. As a result, the binding energies of 7 components including excisanin B, lasiokaurin, rabdophyllin G, rabdoserrin B, rabdosin D, rabdosinate and weisiensin were lower than that of resveratrol. It was indicated that these components had high tyrosinase inhibitory activity. The IC50 values of lasiokaurin and excisanin B were 177 and 142 µmol/mL, which were less than that of resveratrol (183 µmol/mL). It showed that this way was simple, rapid, reliable and effective, which provided a new strategy to screen natural bioactive compounds from plants.


Subject(s)
Isodon , Monophenol Monooxygenase , Molecular Docking Simulation , Chromatography, High Pressure Liquid/methods , Isodon/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Resveratrol , Ultrafiltration/methods , Reproducibility of Results
11.
J Immunol ; 201(8): 2427-2440, 2018 10 15.
Article in English | MEDLINE | ID: mdl-30185519

ABSTRACT

Infection by invasive fungi, such as Candida albicans, Aspergillus fumigatus, and Cryptococcus neoformans, is one of the leading death causes for the increasing population of immunocompromised and immunodeficient patients. Several C-type lectin receptors (CLRs), including Dectin-1, -2, and -3 and Mincle can recognize fungal surface components and initiate the host antifungal immune responses. Nevertheless, it remains to be determined whether other CLRs are involved in antifungal immunity. Our recent study suggests that CD23 (CLEC4J), a CLR and also a well-known B cell surface marker, may function to sense C. albicans components in antifungal immunity. However, it is not clear how CD23 functions as a fungal pattern recognition receptor and whether the antifungal role of CD23 is specific to C. albicans or not. In this study, we show that CD23 can recognize both α-mannan and ß-glucan from the cell wall of C. albicans or A. fumigatus but cannot recognize glucuronoxylomannan from Cryptococcus Through forming a complex with FcRγ, CD23 can induce NF-κB activation. Consistently, CD23-deficient mice were highly susceptible to C. albicans and A. fumigatus but not to C. neoformans infection. The expression of CD23 in activated macrophages is critical for the activation of NF-κB. CD23 deficiency results in impaired expression of NF-κB-dependent genes, especially iNOS, which induces NO production to suppress fungal infection. Together, our studies reveal the CD23-induced signaling pathways and their roles in antifungal immunity, specifically for C. albicans and A. fumigatus, which provides the molecular basis for designing potential therapeutic agents against fungal infection.


Subject(s)
Aspergillosis/immunology , Aspergillus fumigatus/physiology , B-Lymphocytes/metabolism , Candida albicans/physiology , Candidiasis/immunology , Cryptococcosis/immunology , Cryptococcus neoformans/physiology , Receptors, IgE/metabolism , Receptors, Pattern Recognition/metabolism , Animals , Immunity, Innate , Mannans/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B/metabolism , Polysaccharides/metabolism , RAW 264.7 Cells , Receptors, IgE/genetics , Receptors, Pattern Recognition/genetics , Signal Transduction , beta-Glucans/metabolism
13.
J Biol Chem ; 289(43): 30052-62, 2014 Oct 24.
Article in English | MEDLINE | ID: mdl-25202022

ABSTRACT

Previous studies indicate that both Dectin-3 (also called MCL or Clec4d) and Mincle (also called Clec4e), two C-type lectin receptors, can recognize trehalose 6,6'-dimycolate (TDM), a cell wall component from mycobacteria, and induce potent innate immune responses. Interestingly, stimulation of Dectin-3 by TDM can also induce Mincle expression, which may enhance the host innate immune system to sense Mycobacterium infection. However, the mechanism by which Dectin-3 induces Mincle expression is not fully defined. Here, we show that TDM-induced Mincle expression is dependent on Dectin-3-mediated NF-κB, but not nuclear factor of activated T-cells (NFAT), activation, and Dectin-3 induces NF-κB activation through the CARD9-BCL10-MALT1 complex. We found that bone marrow-derived macrophages from Dectin-3-deficient mice were severely defective in the induction of Mincle expression in response to TDM stimulation. This defect is correlated with the failure of TDM-induced NF-κB activation in Dectin-3-deficient bone marrow-derived macrophages. Consistently, inhibition of NF-κB, but not NFAT, impaired TDM-induced Mincle expression, whereas NF-κB, but not NFAT, binds to the Mincle promoter. Dectin-3-mediated NF-κB activation is dependent on the CARD9-Bcl10-MALT1 complex. Finally, mice deficient for Dectin-3 or CARD9 produced much less proinflammatory cytokines and keyhole limpet hemocyanin (KLH)-specific antibodies after immunization with an adjuvant containing TDM. Overall, this study provides the mechanism by which Dectin-3 induces Mincle expression in response to Mycobacterium infection, which will have significant impact to improve adjuvant and design vaccine for antimicrobial infection.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , CARD Signaling Adaptor Proteins/metabolism , Caspases/metabolism , Cord Factors/pharmacology , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Membrane Proteins/genetics , NF-kappa B/metabolism , Neoplasm Proteins/metabolism , Receptors, Immunologic/metabolism , Adaptor Proteins, Signal Transducing/deficiency , Adjuvants, Immunologic/pharmacology , Animals , B-Cell CLL-Lymphoma 10 Protein , CARD Signaling Adaptor Proteins/deficiency , Caspases/deficiency , Cytokines/biosynthesis , Gene Expression Regulation/drug effects , Humans , Lectins, C-Type/deficiency , Membrane Proteins/metabolism , Mice, Inbred C57BL , Models, Biological , Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein , NFATC Transcription Factors/metabolism , Neoplasm Proteins/deficiency , Promoter Regions, Genetic/genetics , Protein Multimerization/drug effects , Protein Subunits/metabolism , Receptors, Immunologic/deficiency , Signal Transduction/drug effects , Transcription Factor RelA/metabolism
14.
Cell Host Microbe ; 32(9): 1459-1461, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39265531

ABSTRACT

During opportunistic pathogenic episodes, Candida albicans employs classical strategies such as the yeast-to-hyphae transition and immunogenic masking. In this issue of Cell Host & Microbe, Luo et al. unveil that the effector protein Cmi1 can be translocated into host cells and targets TBK1, thereby negatively regulating the host's antifungal immune responses.


Subject(s)
Candida albicans , Candidiasis , Host-Pathogen Interactions , Immune Evasion , Candida albicans/immunology , Humans , Host-Pathogen Interactions/immunology , Candidiasis/immunology , Candidiasis/microbiology , Fungal Proteins/immunology , Fungal Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Hyphae/immunology
15.
J Ethnopharmacol ; 321: 117511, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38036016

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Corni Fructus, derived from the fruit of Cornus officinalis Sieb. et Zucc, is a widely utilized traditional Chinese medicine (TCM) with established efficacy in the treatment of diverse chronic kidney diseases. Crude Corni Fructus (CCF) and wine-processed Corni Fructus (WCF) are the main processed forms of Corni Fructus. Generally, TCM is often used after processing (paozhi). Despite the extensive use of processed TCM, the underlying mechanisms of processing for most TCMs have been unclear so far. AIM OF THE STUDY: In this study, an integrated strategy combined renal metabolomics with proteomics was established and investigated the potential processing mechanisms of CCF or WCF on chronic renal failure (CRF) models. MATERIALS AND METHODS: Firstly, the differences in biochemical parameters and pathological histology were compared to evaluate the effects of CCF and WCF on CRF model rats. Then, the tissue differential metabolites and proteins between CCF and WCF on CRF model rats were screened based on metabolomics and proteomics technology. Concurrently, a combined approach of metabolomics and proteomics was employed to investigate the underlying mechanisms associated with these marker metabolic products and proteins. RESULTS: Compared to the MG group, there were 27 distinct metabolites and 143 different proteins observed in the CCF-treatment group, while the WCF-treatment group exhibited 24 distinct metabolites and 379 different proteins. Further, the integration interactions analysis of the protein and lipid metabolite revealed that both WCF and CCF improved tryptophan degradation and LPS/IL-1-mediated inhibition of RXR function. WCF inhibited RXR function more than CCF via the modulation of LPS/IL-1 in the CRF model. Experimental results were validated by qRT-PCR and western blotting. Notably, the gene expression amount and protein levels of FMO3 and CYP2E1 among 8 genes influenced by WCF were higher compared to CCF. CONCLUSION: The results of this study provide a theoretical basis for further study of Corni Fructus with different processing techniques in CRF. The findings also offer guidance for investigating the mechanism of action of herbal medicines in diseases employing diverse processing techniques.


Subject(s)
Cornus , Drugs, Chinese Herbal , Kidney Failure, Chronic , Renal Insufficiency, Chronic , Wine , Rats , Animals , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Drugs, Chinese Herbal/analysis , Lipopolysaccharides/toxicity , Wine/analysis , Kidney Failure, Chronic/drug therapy , Interleukin-1
16.
J Med Chem ; 67(7): 5783-5799, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38526960

ABSTRACT

Neutrophil-mediated immunotherapy is a promising strategy for treating Candida albicans infection due to its potential in dealing with drug-resistant events. Our previous study found that ACT001 exhibited good antifungal immunotherapeutic activity by inhibiting PD-L1 expression in neutrophils, but its strong cytotoxicity and high BBB permeability hindered its antifungal application. To address these deficiencies, a series of novel sulfide derivatives were designed and synthesized based on a slow-release prodrug strategy. Among these derivatives, compound 16 exhibited stronger inhibition of PD-L1 expression, less cytotoxicity to neutrophils, and lower BBB permeability than ACT001. Compound 16 also significantly enhanced neutrophil-mediated antifungal immunity in C. albicans infected mice, with acceptable pharmacokinetic properties and good oral safety. Moreover, pharmacological mechanism studies demonstrated that ACT001 and compound 16 reduced PD-L1 expression in neutrophils by directly targeting STAT3. Briefly, this study provided a novel prototype compound 16 which exhibited great potential in neutrophil-mediated antifungal immunotherapy.


Subject(s)
Antifungal Agents , Furans , Neutrophils , Animals , Mice , Antifungal Agents/pharmacology , Antifungal Agents/metabolism , Neutrophils/metabolism , B7-H1 Antigen , Drug Repositioning , Candida albicans/metabolism
17.
Trends Microbiol ; 31(11): 1090-1092, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37741789

ABSTRACT

During viral infections, stimulator of interferon genes (STING) exerts a positive protective immune response. Chen et al. now shed light on the distinct role of STING in fungal infections. STING translocates to the phagosome to negatively regulate the immune response against Candida albicans infection through the inhibition of Src-involved Syk phosphorylation.

18.
Nat Commun ; 14(1): 6718, 2023 10 23.
Article in English | MEDLINE | ID: mdl-37872182

ABSTRACT

Dimerization of C-type lectin receptors (CLRs) or Toll-like receptors (TLRs) can alter their ligand binding ability, thereby modulating immune responses. However, the possibilities and roles of dimerization between CLRs and TLRs remain unclear. Here we show that C-type lectin receptor-2d (CLEC2D) forms homodimers, as well as heterodimers with TLR2. Quantitative ligand binding assays reveal that both CLEC2D homodimers and CLEC2D/TLR2 heterodimers have a higher binding ability to fungi-derived ß-glucans than TLR2 homodimers. Moreover, homo- or hetero-dimeric CLEC2D mediates ß-glucan-induced ubiquitination and degradation of MyD88 to inhibit the activation of transcription factor IRF5 and subsequent IL-12 production. Clec2d-deficient female mice are resistant to infection with Candida albicans, a human fungal pathogen, owing to the increase of IL-12 production and subsequent generation of IFN-γ-producing NK cells. Together, these data indicate that CLEC2D forms homodimers or heterodimers with TLR2, which negatively regulate antifungal immunity through suppression of IRF5-mediated IL-12 production. These homo- and hetero-dimers of CLEC2D and TLR2 provide an example of receptor dimerization to regulate host innate immunity against microbial infections.


Subject(s)
Toll-Like Receptor 2 , beta-Glucans , Animals , Female , Humans , Mice , Antifungal Agents , beta-Glucans/metabolism , Immunity, Innate , Interferon Regulatory Factors/metabolism , Interleukin-12/metabolism , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Ligands , Toll-Like Receptor 2/metabolism , Toll-Like Receptors/metabolism
19.
Article in English | MEDLINE | ID: mdl-37022453

ABSTRACT

Due to device operating environment limitations and data privacy protection, it is frequently difficult to obtain sufficient high-quality labeled data from devices, resulting in an insufficient generalization ability of fault diagnosis model. Therefore, a high-performance federated learning framework is proposed in this work, which makes improvements in the procedure of model aggregation and local model training. In the model aggregation of central server, an optimization aggregation strategy in which forgetting Kalman filter (FKF) is combined with cubic exponential smoothing (CES) is proposed to improve the efficiency of federated learning. In the local model training of multiclient, a deep learning network combined with multiscale convolution, attention mechanism, and multistage residual connection is proposed, which is able to fully extract multiclient data features simultaneously. Meanwhile, experiments on two machinery fault datasets show that the proposed framework is capable of achieving high accuracy and strong generalization of fault diagnosis on the premise of protecting data privacy in actual industrial situations.

20.
mLife ; 2(2): 159-177, 2023 Jun.
Article in English | MEDLINE | ID: mdl-38817625

ABSTRACT

Candida albicans deploys a variety of mechanisms such as morphological switch and elicitor release to promote virulence. However, the intricate interactions between the fungus and the host remain poorly understood, and a comprehensive inventory of fungal virulence factors has yet to be established. In this study, we identified a C. albicans secretory effector protein Sce1, whose induction and secretion are associated with vagina-simulative conditions and chlamydospore formation. Sequence alignment showed that Sce1 belongs to a Pir family in C. albicans, which is conserved across several fungi and primarily characterized as a ß-glucan binding protein in the Saccharomyces cerevisiae. Mechanically, Sce1 is primarily localized to the cell wall in a cleaved form as an alkali-labile ß-1,3-glucan binding protein and plays a role in masking ß-glucan in acidic environments and chlamydospores, a feature that might underline C. albicans' ability to evade host immunity. Further, a cleaved short form of Sce1 protein could be released into extracellular compartments and presented in bone marrow-derived macrophages infected with chlamydospores. This cleaved short form of Sce1 also demonstrated a unique ability to trigger the caspases-8/9-dependent apoptosis in various host cells. Correspondingly, genetic deletion of SCE1 led to dampened vaginal colonization of C. albicans and diminished fungal virulence during systemic infection. The discovery of Sce1 as a versatile virulence effector that executes at various compartments sheds light on the fungus-host interactions and C. albicans pathogenesis.

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