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1.
Nat Immunol ; 23(8): 1193-1207, 2022 08.
Article in English | MEDLINE | ID: mdl-35879450

ABSTRACT

Innate antiviral immunity deteriorates with aging but how this occurs is not entirely clear. Here we identified SIRT1-mediated DNA-binding domain (DBD) deacetylation as a critical step for IRF3/7 activation that is inhibited during aging. Viral-stimulated IRF3 underwent liquid-liquid phase separation (LLPS) with interferon (IFN)-stimulated response element DNA and compartmentalized IRF7 in the nucleus, thereby stimulating type I IFN (IFN-I) expression. SIRT1 deficiency resulted in IRF3/IRF7 hyperacetylation in the DBD, which inhibited LLPS and innate immunity, resulting in increased viral load and mortality in mice. By developing a genetic code expansion orthogonal system, we demonstrated the presence of an acetyl moiety at specific IRF3/IRF7 DBD site/s abolish IRF3/IRF7 LLPS and IFN-I induction. SIRT1 agonists rescued SIRT1 activity in aged mice, restored IFN signaling and thus antagonized viral replication. These findings not only identify a mechanism by which SIRT1 regulates IFN production by affecting IRF3/IRF7 LLPS, but also provide information on the drivers of innate immunosenescence.


Subject(s)
Antiviral Agents , Sirtuin 1 , Animals , Immunity, Innate , Interferon Regulatory Factor-3/metabolism , Interferon Regulatory Factor-7/genetics , Interferon Regulatory Factor-7/metabolism , Mice , Signal Transduction , Sirtuin 1/genetics , Sirtuin 1/metabolism , Virus Replication
2.
Nat Immunol ; 19(3): 233-245, 2018 03.
Article in English | MEDLINE | ID: mdl-29358709

ABSTRACT

Malignancies can compromise innate immunity, but the mechanisms of this are largely unknown. Here we found that, via tumor-derived exosomes (TEXs), cancers were able to transfer activated epidermal growth factor receptor (EGFR) to host macrophages and thereby suppress innate antiviral immunity. Screening of the human kinome identified the kinase MEKK2 in macrophages as an effector of TEX-delivered EGFR that negatively regulated the antiviral immune response. In the context of experimental tumor implantation, MEKK2-deficient mice were more resistant to viral infection than were wild-type mice. Injection of TEXs into mice reduced innate immunity, increased viral load and increased morbidity in an EGFR- and MEKK2-dependent manner. MEKK2 phosphorylated IRF3, a transcription factor crucial for the production of type I interferons; this triggered poly-ubiquitination of IRF3 and blocked its dimerization, translocation to the nucleus and transcriptional activity after viral infection. These findings identify a mechanism by which cancer cells can dampen host innate immunity and potentially cause patients with cancer to become immunocompromised.


Subject(s)
ErbB Receptors/immunology , Exosomes/immunology , Immunity, Innate/immunology , Neoplasms/immunology , Virus Diseases/immunology , Adult , Animals , ErbB Receptors/metabolism , Exosomes/metabolism , Female , Humans , Immunocompromised Host/immunology , MAP Kinase Kinase Kinase 2/immunology , MAP Kinase Kinase Kinase 2/metabolism , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged
4.
Nat Immunol ; 18(7): 733-743, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28481329

ABSTRACT

The transcription regulator YAP controls organ size by regulating cell growth, proliferation and apoptosis. However, whether YAP has a role in innate antiviral immunity is largely unknown. Here we found that YAP negatively regulated an antiviral immune response. YAP deficiency resulted in enhanced innate immunity, a diminished viral load, and morbidity in vivo. YAP blocked dimerization of the transcription factor IRF3 and impeded translocation of IRF3 to the nucleus after viral infection. Notably, virus-activated kinase IKKɛ phosphorylated YAP at Ser403 and thereby triggered degradation of YAP in lysosomes and, consequently, relief of YAP-mediated inhibition of the cellular antiviral response. These findings not only establish YAP as a modulator of the activation of IRF3 but also identify a previously unknown regulatory mechanism independent of the kinases Hippo and LATS via which YAP is controlled by the innate immune pathway.


Subject(s)
Adaptor Proteins, Signal Transducing/immunology , Fibroblasts/immunology , I-kappa B Kinase/metabolism , Immunity, Innate/immunology , Lysosomes/metabolism , Macrophages/immunology , Phosphoproteins/immunology , Rhabdoviridae Infections/immunology , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Animals , CRISPR-Cas Systems , Cell Cycle Proteins , Chemokine CCL5/genetics , Chemokine CCL5/immunology , Chemokine CXCL10/genetics , Chemokine CXCL10/immunology , Fluorescent Antibody Technique , Gene Editing , HEK293 Cells , HeLa Cells , Humans , Immunoblotting , Immunoprecipitation , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/immunology , Interferon Regulatory Factor-3/metabolism , Interferon-beta/genetics , Interferon-beta/immunology , Lung/immunology , Lung/pathology , Mice , Microscopy, Confocal , Phosphoproteins/genetics , Phosphoproteins/metabolism , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/immunology , RAW 264.7 Cells , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Rhabdoviridae Infections/pathology , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/immunology , Vesiculovirus , Viral Load , YAP-Signaling Proteins
5.
Small ; : e2308383, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-38073323

ABSTRACT

Acidic residues (Asp and Glu) have a high prevalence on protein surfaces, but cross-linking reactions targeting these residues are limited. Existing methods either require high-concentration coupling reagents or have low structural compatibility. Here a previously reported "plant-and-cast" strategy is extended to develop heterobifunctional cross-linkers. These cross-linkers first react rapidly with Lys sidechains and then react with Asp and Glu sidechains, in a proximity-enhanced fashion. The cross-linking reaction proceeds at neutral pH and room temperature without coupling reagents. The efficiency and robustness of cross-linking using model proteins, ranging from small monomeric proteins to large protein complexes are demonstrated. Importantly, it is shown that this type of cross-linkers are efficient at identifying protein-protein interactions involving acidic domains. The Cross-linking mass spectrometry (XL-MS) study with p53 identified 87 putative binders of the C-terminal domain of p53. Among them, SARNP, ZRAB2, and WBP11 are shown to regulate the expression and alternative splicing of p53 target genes. Thus, these carboxylate-reactive cross-linkers will further expand the power of XL-MS in the analysis of protein structures and protein-protein interactions.

6.
Opt Lett ; 45(8): 2347-2350, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-32287230

ABSTRACT

We demonstrated a high-power long-wave infrared optical parametric oscillator at 9.8 µm based on a type-I phase-matching ${{\rm ZnGeP}_2}$ZnGeP2 crystal. By using a ${Q}$Q-switched 2091 nm Ho:YAG laser with pulse repetition frequency of 10 kHz as the pump source, the maximum average output power of 3.51 W at 9.8 µm was achieved with incident pump power of 90 W, corresponding to a slope efficiency of 4.81% and conversion efficiency at maximum pump power of 3.9%. The pulse width of 19.6 ns and linewidth of 142 nm were obtained at maximum output level. In addition, the beam quality factor ${M^2}$M2 was measured to be ${\sim}{2.2}$∼2.2.

7.
Opt Lett ; 44(3): 715-718, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30702718

ABSTRACT

We demonstrate a 102 W middle infrared ZnGeP2 (ZGP) optical parametric amplifier (OPA) pumped by a 2097-nm Q-switched Ho:YAG laser at a pulse repetition frequency of 10 kHz. The seed middle infrared laser was produced by a ZGP optical parametric oscillator. Its average power was 28.4 W pumped by a 50 W 2097-nm laser. By thermal lens compensation, the beam factor M2 reduced from 3.1 to 2.1. When the incident Ho pump power was 120 W, the middle infrared ZGP OPA yielded the maximum average output power of 102 W and slope efficiency of 61.7%. The overall optical conversion efficiency of 60% from Ho to middle infrared was obtained for the whole middle infrared laser system. In addition, at the maximum average output power, the beam quality factors of the middle infrared ZGP OPA were measured to be about 2.7 and 2.8 for horizontal and vertical directions, respectively.

8.
Opt Lett ; 43(24): 5989-5992, 2018 Dec 15.
Article in English | MEDLINE | ID: mdl-30547987

ABSTRACT

A high-efficiency and high-brightness Ho:YAG master-oscillator power-amplifier (MOPA) system dual-end pumped by Tm:YLF lasers was demonstrated. The maximum output power of 231 W at a wavelength of 2090.7 nm was achieved with pulse repetition frequency of 10 kHz and pulse width of 22.9 ns, corresponding to pulse energy of 23.1 mJ and peak power of ∼1 MW. The extraction efficiency of the amplifier system was more than 60%. The beam quality factor M2 was measured to be ∼1.05. Using the Ho:YAG MOPA system as the pump source, the ZnGeP2 optical parametric oscillator delivered an output power of 110 W, corresponding to slope efficiency of 62%.

9.
J Biol Chem ; 291(2): 980-8, 2016 Jan 08.
Article in English | MEDLINE | ID: mdl-26586918

ABSTRACT

Carcinoembryonic antigen-related cell adhesion molecule 2 (CEACAM2) regulates food intake as demonstrated by hyperphagia in mice with the Ceacam2 null mutation (Cc2(-/-)). This study investigated whether CEACAM2 also regulates insulin secretion. Ceacam2 deletion caused an increase in ß-cell secretory function, as assessed by hyperglycemic clamp analysis, without affecting insulin response. Although CEACAM2 is expressed in pancreatic islets predominantly in non-ß-cells, basal plasma levels of insulin, glucagon and somatostatin, islet areas, and glucose-induced insulin secretion in pooled Cc2(-/-) islets were all normal. Consistent with immunofluorescence analysis showing CEACAM2 expression in distal intestinal villi, Cc2(-/-) mice exhibited a higher release of oral glucose-mediated GLP-1, an incretin that potentiates insulin secretion in response to glucose. Compared with wild type, Cc2(-/-) mice also showed a higher insulin excursion during the oral glucose tolerance test. Pretreating with exendin(9-39), a GLP-1 receptor antagonist, suppressed the effect of Ceacam2 deletion on glucose-induced insulin secretion. Moreover, GLP-1 release into the medium of GLUTag enteroendocrine cells was increased with siRNA-mediated Ceacam2 down-regulation in parallel to an increase in Ca(2+) entry through L-type voltage-dependent Ca(2+) channels. Thus, CEACAM2 regulates insulin secretion, at least in part, by a GLP-1-mediated mechanism, independent of confounding metabolic factors.


Subject(s)
Cell Adhesion Molecules/deficiency , Glucagon-Like Peptide 1/metabolism , Glucose/pharmacology , Animals , Antigens, CD/metabolism , Calcium Channels, L-Type/metabolism , Cell Adhesion Molecules/metabolism , Fluorescent Antibody Technique , Glucose Tolerance Test , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Male , Mice , Wakefulness
10.
Opt Express ; 24(6): 6083-7, 2016 Mar 21.
Article in English | MEDLINE | ID: mdl-27136802

ABSTRACT

We, for the first time, demonstrate a tunable mid-infrared BaGa4Se7-based optical parametric oscillator pumped by a acousto-optical Q-switched Ho:YAG laser at 2090.6 nm. Up to 1.55 W of average power was generated in the 3-5 µm range, corresponding to an optical-to-optical conversion efficiency of 14.4% and a slope efficiency of 19.9%. The mid-IR radiation spectra were also seriously researched at different phase-matched angles. The tunable range was 3.49-4.13 µm for the signal, and 5.19-4.34 µm for the idler.

11.
J Org Chem ; 80(22): 11330-8, 2015 Nov 20.
Article in English | MEDLINE | ID: mdl-26523421

ABSTRACT

Cinchona alkaloid squaramide can effectively catalyze the asymmetric Michael addition of α-aryl isocyanoacetates to ß-trifluoromethylated enones, affording the corresponding adducts with an adjacent chiral tertiary carbon center bearing a CF3 group and a quaternary carbon center in moderate to good yields along with excellent stereoselectivities. The adduct can be easily transformed into biologically attractive chiral ß-trifluoromethylated pyrroline carboxylate in high yield via an isocyano group hydrolysis/cyclization/dehydration cascade reaction by treating with acid. The one-pot enantioselective Michael addition/isocyano group hydrolysis/cyclization/dehydration sequential protocol has also been investigated.

12.
Opt Lett ; 39(23): 6589-92, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25490628

ABSTRACT

We reported a high-power ZnGeP2 (ZGP) optical parametric oscillator (OPO) pumped by a Q-switched Ho:YAG laser. The maximum output power of the ZGP OPO was 41.2 W at 107.0 W incident Ho pump power, corresponding to a slope efficiency of 44.6%. The ZGP OPO produced 16-ns mid-IR pulse laser in the 3.74-3.98 µm and 4.38-4.76 µm spectral regions simultaneously. The beam quality was measured to be M²<4.37. The continuous wave maximum average output power of the Ho:YAG laser was 128 W, corresponding to a slope efficiency of 65.8%.

13.
Curr Treat Options Oncol ; 15(3): 351-64, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25064175

ABSTRACT

OPINION STATEMENT: Cancers of the upper gastrointestinal tract form a prevalent and highly morbid group of malignancies. Specifically, median survival for patients with esophagus, gastric, and pancreatic cancers is less than 1 year, and although there has been progress in therapeutic strategies, the vast majority of newly diagnosed patients with these cancers will die of their disease. (18)F-FDG PET ((18)f-fluorodeoxyglucose positron emission tomography) is a useful but underutilized resource for identifying metastatic disease in the upper gastrointestinal tract. While prevalent in the United States, worldwide, (18)F-FDG PET is underutilized especially in countries with a growing emergence of gastroesophageal cancers, despite evidence of clear benefit in cancer staging, and in some cases response assessment and surveillance.


Subject(s)
Fluorodeoxyglucose F18 , Gastrointestinal Neoplasms/diagnostic imaging , Gastrointestinal Neoplasms/pathology , Positron-Emission Tomography , Upper Gastrointestinal Tract/diagnostic imaging , Upper Gastrointestinal Tract/pathology , Humans , Pancreatic Neoplasms/diagnostic imaging
14.
Drug Deliv ; 31(1): 2342844, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38659328

ABSTRACT

High intensity focused ultrasound (HIFU) has demonstrated its safety, efficacy and noninvasiveness in the ablation of solid tumor. However, its further application is limited by its inherent deficiencies, such as postoperative recurrence caused by incomplete ablation and excessive intensity affecting surrounding healthy tissues. Recent research has indicated that the integration of nanomaterials with HIFU exhibits a promising synergistic effect in tumor ablation. The concurrent utilization of nanomaterials with HIFU can help overcome the limitations of HIFU by improving targeting and ablation efficiency, expanding operation area, increasing operation accuracy, enhancing stability and bio-safety during the process. It also provides a platform for multi-therapy and multi-mode imaging guidance. The present review comprehensively expounds upon the synergistic mechanism between nanomaterials and HIFU, summarizes the research progress of nanomaterials as cavitation nuclei and drug carriers in combination with HIFU for tumor ablation. Furthermore, this review highlights the potential for further exploration in the development of novel nanomaterials that enhance the synergistic effect with HIFU on tumor ablation.


Subject(s)
High-Intensity Focused Ultrasound Ablation , Nanostructures , Neoplasms , Humans , Neoplasms/therapy , Neoplasms/drug therapy , High-Intensity Focused Ultrasound Ablation/methods , Animals , Drug Carriers/chemistry , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacology , Combined Modality Therapy
15.
World Neurosurg ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38964458

ABSTRACT

OBJECTIVE: We aimed to preliminarily explore the efficacy and safety of unilateral biportal endoscopy (UBE) for the treatment of epidural cement leaks. We report a patient who underwent epidural cement leakage removal and achieved endoscopic spinal decompression. METHODS: A 67-year-old female patient underwent biportal endoscopic paraspinal decompression following percutaneous vertebroplasty for an osteoporotic fracture that resulted in neurologic impairment due to epidural cement leakage. A transforaminal biportal endoscopic surgery was performed to remove the leaked cement, and the left L1 and bilateral L2 nerves were decompressed. RESULTS: The patient's postoperative clinical course was uneventful. CONCLUSIONS: A paraspinal approach that avoids a posterior approach reduces the need to remove stabilizing facet bone, is truly minimally invasive and does not involve an instrumented fusion, maybe a helpful addition in the minimally invasive spine surgeon's armamentarium.

16.
Nat Struct Mol Biol ; 30(6): 785-799, 2023 06.
Article in English | MEDLINE | ID: mdl-37188808

ABSTRACT

Mitochondrial antiviral signaling protein (MAVS) is an adapter that recruits and activates IRF3. However, the mechanisms underpinning the interplay between MAVS and IRF3 are largely unknown. Here we show that small ubiquitin-like modifier (SUMO)-specific protease 1 negatively regulates antiviral immunity by deSUMOylating MAVS. Upon virus infection, PIAS3-induced poly-SUMOylation promotes lysine 63-linked poly-ubiquitination and aggregation of MAVS. Notably, we observe that SUMO conjugation is required for MAVS to efficiently produce phase-separated droplets through association with a newly identified SUMO-interacting motif (SIM) in MAVS. We further identify a yet-unknown SIM in IRF3 that mediates its enrichment to the multivalent MAVS droplets. Conversely, IRF3 phosphorylation at crucial residues close to SIM rapidly disables SUMO-SIM interactions and releases activated IRF3 from MAVS. Our findings implicate SUMOylation in MAVS phase separation and suggest a thus far unknown regulatory process by which IRF3 can be efficiently recruited and released to facilitate timely activation of antiviral responses.


Subject(s)
Sumoylation , Ubiquitin , Ubiquitination , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism , Antiviral Agents
17.
Org Biomol Chem ; 10(39): 7970-9, 2012 Oct 21.
Article in English | MEDLINE | ID: mdl-22941464

ABSTRACT

A highly enantioselective Michael addition of 3-aryloxindole to vinyl bisphosphonate ester catalyzed by a cinchonidine derived thiourea catalyst has been investigated. The corresponding adducts, containing a chiral quaternary carbon center and geminal bisphosphonate ester fragment at the 3-position of the oxindole, were obtained in moderate to good yields (65-92%) and moderate to good enantioselectivities (up to 92% ee).


Subject(s)
Cinchona Alkaloids/chemistry , Diphosphonates/chemistry , Esters/chemistry , Indoles/chemistry , Thiourea/chemistry , Catalysis , Molecular Structure , Oxindoles , Stereoisomerism
18.
Appl Opt ; 51(33): 7887-90, 2012 Nov 20.
Article in English | MEDLINE | ID: mdl-23207298

ABSTRACT

High-efficient CW and Q-switched Ho:YAG lasers resonantly dual-end-pumped by two diode-pumped Tm:YLF lasers at 1908 nm were investigated. A maximum slope efficiency of 74.8% in CW operation as well as a maximum output power of 58.7 W at 83.2 W incident pump power was achieved, which corresponded to an optical-to-optical conversion efficiency of 70.6%. The maximum pulse energy of 2.94 mJ was achieved, with a 31 ns FWHM pulse width and a peak power of approximately 94.7 kW.


Subject(s)
Lasers, Solid-State , Energy Transfer , Equipment Design , Equipment Failure Analysis
19.
Signal Transduct Target Ther ; 7(1): 143, 2022 04 29.
Article in English | MEDLINE | ID: mdl-35487886

ABSTRACT

The global coronavirus disease 2019 (COVID-19) pandemic is currently ongoing. It is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A high proportion of COVID-19 patients exhibit gastrointestinal manifestations such as diarrhea, nausea, or vomiting. Moreover, the respiratory and gastrointestinal tracts are the primary habitats of human microbiota and targets for SARS-CoV-2 infection as they express angiotensin-converting enzyme-2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) at high levels. There is accumulating evidence that the microbiota are significantly altered in patients with COVID-19 and post-acute COVID-19 syndrome (PACS). Microbiota are powerful immunomodulatory factors in various human diseases, such as diabetes, obesity, cancers, ulcerative colitis, Crohn's disease, and certain viral infections. In the present review, we explore the associations between host microbiota and COVID-19 in terms of their clinical relevance. Microbiota-derived metabolites or components are the main mediators of microbiota-host interactions that influence host immunity. Hence, we discuss the potential mechanisms by which microbiota-derived metabolites or components modulate the host immune responses to SARS-CoV-2 infection. Finally, we review and discuss a variety of possible microbiota-based prophylaxes and therapies for COVID-19 and PACS, including fecal microbiota transplantation (FMT), probiotics, prebiotics, microbiota-derived metabolites, and engineered symbiotic bacteria. This treatment strategy could modulate host microbiota and mitigate virus-induced inflammation.


Subject(s)
COVID-19 , Microbiota , COVID-19/complications , COVID-19/therapy , Cell Line , Humans , Peptidyl-Dipeptidase A/metabolism , SARS-CoV-2 , Post-Acute COVID-19 Syndrome
20.
Cell Rep ; 41(8): 111661, 2022 11 22.
Article in English | MEDLINE | ID: mdl-36417850

ABSTRACT

Innate immunity is critical for the early detection and elimination of viral invasion. Extracellular signals are crucial for host resistance; however, how extracellular factors prepare the innate immunity for rapid antiviral response remains elusive. Here, we find that serum deprivation largely restricts the innate antiviral responses to RNA and DNA viruses. When serum is supplied, serine/threonine-protein kinase 38-like (STK38L), induced by serum response factor (SRF), phosphorylates IRF3 at Ser303, which prevents IRF3 from proteasome-mediated degradation in the rest state (non-infected), and ensures that enough IRF3 is called in the primed state (infected). STK38L-deficient mice exhibit compromised innate antiviral responses and elevated viral proliferation and mortality. Moreover, lysophosphatidic acid (LPA) or sphingosine 1-phosphate (S1P), the crucial activators of SRF, rescue immunosuppression caused by serum deprivation. These findings identify the SRF-STK38L-IRF3 axis as a novel mechanism that maintains the host in a pro-active state when not infected, which ensures the rapid immune response against virus.


Subject(s)
Antiviral Agents , Viruses , Animals , Mice , Antiviral Agents/pharmacology , Immunity, Innate , Interferon Regulatory Factor-3/metabolism , Phosphorylation , Viruses/metabolism , Protein Serine-Threonine Kinases/metabolism
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