Longitudinal analyses reveal immunological misfiring in severe COVID-19.
Recent studies have provided insights into the pathogenesis of coronavirus disease 2019 (COVID-19)1-4. However,the longitudinal immunological correlates of disease outcome remain unclear. Here we serially analysed immune responses in 113 patients with moderate or severe COVID-19. Immune profiling revealed an overall increase in innate cell lineages,with a concomitant reduction in T cell number. An early elevation in cytokine levels was associated with worse disease outcomes. Following an early increase in cytokines,patients with moderate COVID-19 displayed a progressive reduction in type 1 (antiviral) and type 3 (antifungal) responses. By contrast,patients with severe COVID-19 maintained these elevated responses throughout the course of the disease. Moreover,severe COVID-19 was accompanied by an increase in multiple type 2 (anti-helminths) effectors,including interleukin-5 (IL-5),IL-13,immunoglobulin E and eosinophils. Unsupervised clustering analysis identified four immune signatures,representing growth factors (A),type-2/3 cytokines (B),mixed type-1/2/3 cytokines (C),and chemokines (D) that correlated with three distinct disease trajectories. The immune profiles of patients who recovered from moderate COVID-19 were enriched in tissue reparative growth factor signature A,whereas the profiles of those with who developed severe disease had elevated levels of all four signatures. Thus,we have identified a maladapted immune response profile associated with severe COVID-19 and poor clinical outcome,as well as early immune signatures that correlate with divergent disease trajectories.
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E. Lorenzo et al. (mar 2002)
The Journal of biological chemistry 277 13 10883--92
Doxorubicin induces apoptosis and CD95 gene expression in human primary endothelial cells through a p53-dependent mechanism.
Regulation of the homeostasis of vascular endothelium is critical for the processes of vascular remodeling and angiogenesis under physiological and pathological conditions. Here we show that doxorubicin (Dox),a drug used in antitumor therapy,triggered a marked accumulation of p53 and induced CD95 gene expression and apoptosis in proliferating human umbilical vein endothelial cells (HUVECs). Transfection and site-directed mutagenesis experiments using the CD95 promoter fused to an intronic enhancer indicated the requirement for a p53 site for Dox-induced promoter activation. Furthermore,the p53 inhibitor pifithrin-alpha (PFT-alpha) blocked both promoter inducibility and protein up-regulation of CD95 in response to Dox. Up-regulated CD95 in Dox-treated cells was functional in eliciting apoptosis upon incubation of the cells with an agonistic CD95 antibody. However,Dox-mediated apoptosis was independent of CD95/CD95L interaction. The analysis of apoptosis in the presence of PFT-alpha and benzyloxycarbonyl-Val-Ala-dl-Asp-fluoromethylketone revealed that both p53 and caspase activation are required for Dox-mediated apoptosis of HUVECs. Finally,Dox triggered Bcl-2 down-regulation,cytochrome c release from mitochondria,and the activation of caspases 9 and 3,suggesting the involvement of a mitochondrially operated pathway of apoptosis. These results highlight the role of p53 in the response of primary endothelial cells to genotoxic drugs and may reveal a novel mechanism underlying the antitumoral properties of Dox,related to its ability to induce apoptosis in proliferating endothelial cells.
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Y. Liu-Chittenden et al. (jun 2012)
Genes {\&} development 26 12 1300--5
Genetic and pharmacological disruption of the TEAD-YAP complex suppresses the oncogenic activity of YAP.
The Drosophila TEAD ortholog Scalloped is required for Yki-mediated overgrowth but is largely dispensable for normal tissue growth,suggesting that its mammalian counterpart may be exploited for selective inhibition of oncogenic growth driven by YAP hyperactivation. Here we test this hypothesis genetically and pharmacologically. We show that a dominant-negative TEAD molecule does not perturb normal liver growth but potently suppresses hepatomegaly/tumorigenesis resulting from YAP overexpression or Neurofibromin 2 (NF2)/Merlin inactivation. We further identify verteporfin as a small molecule that inhibits TEAD-YAP association and YAP-induced liver overgrowth. These findings provide proof of principle that inhibiting TEAD-YAP interactions is a pharmacologically viable strategy against the YAP oncoprotein.
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Z. Liu et al. (nov 2020)
Cell 183 4 1117--1133.e19
Detecting Tumor Antigen-Specific T Cells via Interaction-Dependent Fucosyl-Biotinylation.
Re-activation and clonal expansion of tumor-specific antigen (TSA)-reactive T cells are critical to the success of checkpoint blockade and adoptive transfer of tumor-infiltrating lymphocyte (TIL)-based therapies. There are no reliable markers to specifically identify the repertoire of TSA-reactive T cells due to their heterogeneous composition. We introduce FucoID as a general platform to detect endogenous antigen-specific T cells for studying their biology. Through this interaction-dependent labeling approach,intratumoral TSA-reactive CD4+,CD8+ T cells,and TSA-suppressive CD4+ T cells can be detected and separated from bystander T cells based on their cell-surface enzymatic fucosyl-biotinylation. Compared to bystander TILs,TSA-reactive TILs possess a distinct T cell receptor (TCR) repertoire and unique gene features. Although exhibiting a dysfunctional phenotype,TSA-reactive CD8+ TILs possess substantial capabilities of proliferation and tumor-specific killing. Featuring genetic manipulation-free procedures and a quick turnover cycle,FucoID should have the potential of accelerating the pace of personalized cancer treatment.
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Z. Liu et al. (oct 2020)
Developmental cell 55 2 224--236.e6
Super-Resolution Microscopy and FIB-SEM Imaging Reveal Parental Centriole-Derived, Hybrid Cilium in Mammalian Multiciliated Cells.
Motile cilia are cellular beating machines that play a critical role in mucociliary clearance,cerebrospinal fluid movement,and fertility. In the airways,hundreds of motile cilia present on the surface of a multiciliated epithelia cell beat coordinately to protect the epithelium from bacteria,viruses,and harmful particulates. During multiciliated cell differentiation,motile cilia are templated from basal bodies,each extending a basal foot-an appendage linking motile cilia together to ensure coordinated beating. Here,we demonstrate that among the many motile cilia of a multiciliated cell,a hybrid cilium with structural features of both primary and motile cilia is harbored. The hybrid cilium is conserved in mammalian multiciliated cells,originates from parental centrioles,and its cellular position is biased and dependent on ciliary beating. Furthermore,we show that the hybrid cilium emerges independently of other motile cilia and functions in regulating basal body alignment.
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Q. Liu et al. (apr 2013)
Cancer research 73 8 2574--86
Characterization of Torin2, an ATP-competitive inhibitor of mTOR, ATM, and ATR.
mTOR is a highly conserved serine/threonine protein kinase that serves as a central regulator of cell growth,survival,and autophagy. Deregulation of the PI3K/Akt/mTOR signaling pathway occurs commonly in cancer and numerous inhibitors targeting the ATP-binding site of these kinases are currently undergoing clinical evaluation. Here,we report the characterization of Torin2,a second-generation ATP-competitive inhibitor that is potent and selective for mTOR with a superior pharmacokinetic profile to previous inhibitors. Torin2 inhibited mTORC1-dependent T389 phosphorylation on S6K (RPS6KB1) with an EC(50) of 250 pmol/L with approximately 800-fold selectivity for cellular mTOR versus phosphoinositide 3-kinase (PI3K). Torin2 also exhibited potent biochemical and cellular activity against phosphatidylinositol-3 kinase-like kinase (PIKK) family kinases including ATM (EC(50),28 nmol/L),ATR (EC(50),35 nmol/L),and DNA-PK (EC(50),118 nmol/L; PRKDC),the inhibition of which sensitized cells to Irradiation. Similar to the earlier generation compound Torin1 and in contrast to other reported mTOR inhibitors,Torin2 inhibited mTOR kinase and mTORC1 signaling activities in a sustained manner suggestive of a slow dissociation from the kinase. Cancer cell treatment with Torin2 for 24 hours resulted in a prolonged block in negative feedback and consequent T308 phosphorylation on Akt. These effects were associated with strong growth inhibition in vitro. Single-agent treatment with Torin2 in vivo did not yield significant efficacy against KRAS-driven lung tumors,but the combination of Torin2 with mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor AZD6244 yielded a significant growth inhibition. Taken together,our findings establish Torin2 as a strong candidate for clinical evaluation in a broad number of oncologic settings where mTOR signaling has a pathogenic role.
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H. R. Lijnen et al. (may 2011)
The Journal of pharmacology and experimental therapeutics 337 2 457--64
Growth arrest-specific protein 6 receptor antagonism impairs adipocyte differentiation and adipose tissue development in mice.
A low-molecular-weight receptor tyrosine kinase inhibitor,1-(6,7-dihydro-5H-benzo(6,7)cyclohepta(1,2-c)pyridazin-3-yl)-N3-((7-pyrrolidin-1-yl)-6,7,8,9-tetrahydro-5H-benzo(7)annulene-2-yl)-1H-1,2,4-triazole-3,5-diamine (R428) with high affinity and selectivity for the growth arrest-specific protein 6 (GAS6) receptor Axl was used to study a potential role of GAS6 signaling in adiposity. In vitro,R428 caused a concentration-dependent inhibition of preadipocyte differentiation into mature adipocytes,as evidenced by reduced lipid uptake. Inhibition of Axl-mediated signaling was confirmed by reduced levels of phospho-Akt activity. In vivo,oral administration of R428 for 5 weeks to mice kept on a high-fat diet resulted in significantly reduced weight gain and subcutaneous and gonadal fat mass. This was associated with marked adipocyte hypotrophy,enhanced macrophage infiltration,and apoptosis. Thus,affecting GAS6 signaling through receptor antagonism using a low-molecular-weight Axl antagonist impairs adipocyte differentiation and reduces adipose tissue development in a murine model of nutritionally induced obesity.
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J. S. Lewis-Wambi et al. ( 2008)
Breast cancer research : BCR 10 6 R104
Buthionine sulfoximine sensitizes antihormone-resistant human breast cancer cells to estrogen-induced apoptosis.
INTRODUCTION Estrogen deprivation using aromatase inhibitors is one of the standard treatments for postmenopausal women with estrogen receptor (ER)-positive breast cancer. However,one of the consequences of prolonged estrogen suppression is acquired drug resistance. Our group is interested in studying antihormone resistance and has previously reported the development of an estrogen deprived human breast cancer cell line,MCF-7:5C,which undergoes apoptosis in the presence of estradiol. In contrast,another estrogen deprived cell line,MCF-7:2A,appears to have elevated levels of glutathione (GSH) and is resistant to estradiol-induced apoptosis. In the present study,we evaluated whether buthionine sulfoximine (BSO),a potent inhibitor of glutathione (GSH) synthesis,is capable of sensitizing antihormone resistant MCF-7:2A cells to estradiol-induced apoptosis. METHODS Estrogen deprived MCF-7:2A cells were treated with 1 nM 17beta-estradiol (E2),100 microM BSO,or 1 nM E2 + 100 microM BSO combination in vitro,and the effects of these agents on cell growth and apoptosis were evaluated by DNA quantitation assay and annexin V and terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) staining. The in vitro results of the MCF-7:2A cell line were further confirmed in vivo in a mouse xenograft model. RESULTS Exposure of MCF-7:2A cells to 1 nM E2 plus 100 microM BSO combination for 48 to 96 h produced a sevenfold increase in apoptosis whereas the individual treatments had no significant effect on growth. Induction of apoptosis by the combination treatment of E2 plus BSO was evidenced by changes in Bcl-2 and Bax expression. The combination treatment also markedly increased phosphorylated c-Jun N-terminal kinase (JNK) levels in MCF-7:2A cells and blockade of the JNK pathway attenuated the apoptotic effect of E2 plus BSO. Our in vitro findings corroborated in vivo data from a mouse xenograft model in which daily administration of BSO either as a single agent or in combination with E2 significantly reduced tumor growth of MCF-7:2A cells. CONCLUSIONS Our data indicates that GSH participates in retarding apoptosis in antihormone-resistant human breast cancer cells and that depletion of this molecule by BSO may be critical in predisposing resistant cells to E2-induced apoptotic cell death. We suggest that these data may form the basis of improving therapeutic strategies for the treatment of antihormone resistant ER-positive breast cancer.
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B. V. Le et al. (oct 2020)
Cell reports 33 1 108221
TGF$\beta$R-SMAD3 Signaling Induces Resistance to PARP Inhibitors in the Bone Marrow Microenvironment.
Synthetic lethality triggered by PARP inhibitor (PARPi) yields promising therapeutic results. Unfortunately,tumor cells acquire PARPi resistance,which is usually associated with the restoration of homologous recombination,loss of PARP1 expression,and/or loss of DNA double-strand break (DSB) end resection regulation. Here,we identify a constitutive mechanism of resistance to PARPi. We report that the bone marrow microenvironment (BMM) facilitates DSB repair activity in leukemia cells to protect them against PARPi-mediated synthetic lethality. This effect depends on the hypoxia-induced overexpression of transforming growth factor beta receptor (TGF$\beta$R) kinase on malignant cells,which is activated by bone marrow stromal cells-derived transforming growth factor beta 1 (TGF-$\beta$1). Genetic and/or pharmacological targeting of the TGF-$\beta$1-TGF$\beta$R kinase axis results in the restoration of the sensitivity of malignant cells to PARPi in BMM and prolongs the survival of leukemia-bearing mice. Our finding may lead to the therapeutic application of the TGF$\beta$R inhibitor in patients receiving PARPis.
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O. Laselva et al. (sep 2020)
Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society 19 5 717--727
Functional rescue of c.3846G\textgreaterA (W1282X) in patient-derived nasal cultures achieved by inhibition of nonsense mediated decay and protein modulators with complementary mechanisms of action.
BACKGROUND The nonsense mutation,c.3846G{\textgreater}A (aka: W1282X-CFTR) leads to a truncated transcript that is susceptible to nonsense-mediated decay (NMD) and produces a shorter protein that is unstable and lacks normal channel activity in patient-derived tissues. However,if overexpressed in a heterologous expression system,the truncated mutant protein has been shown to mediate CFTR channel function following the addition of potentiators. In this study,we asked if a quadruple combination of small molecules that together inhibit nonsense mediated decay,stabilize both halves of the mutant protein and potentiate CFTR channel activity could rescue the functional expression of W1282X-CFTR in patient derived nasal cultures. METHODS We identified the CFTR domains stabilized by corrector compounds supplied from AbbVie using a fragment based,biochemical approach. Rescue of the channel function of W1282X.-CFTR protein by NMD inhibition and small molecule protein modulators was studied using a bronchial cell line engineered to express W1282X and in primary nasal epithelial cultures derived from four patients homozygous for this mutation. RESULTS We confirmed previous studies showing that inhibition of NMD using the inhibitor: SMG1i,led to an increased abundance of the shorter transcript in a bronchial cell line. Interestingly,on top of SMG1i,treatment with a combination of two new correctors developed by Galapagos/AbbVie (AC1 and AC2-2,separately targeting either the first or second half of CFTR and promoting assembly,significantly increased the potentiated channel activity by the mutant in the bronchial epithelial cell line and in patient-derived nasal epithelial cultures. The average rescue effect in primary cultures was approximately 50{\%} of the regulated chloride conductance measured in non-CF cultures. CONCLUSIONS These studies provide the first in-vitro evidence in patient derived airway cultures that the functional defects incurred by W1282X,has the potential to be effectively repaired pharmacologically.
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Incorporation of metabolically stable ketones into a small molecule probe to increase potency and water solubility.
Introducing a reactive carbonyl to a scaffold that does not otherwise have an electrophilic functionality to create a reversible covalent inhibitor is a potentially useful strategy for enhancing compound potency. However,aldehydes are metabolically unstable,which precludes the use of this strategy for compounds to be tested in animal models or in human clinical studies. To overcome this limitation,we designed ketone-based functionalities capable of forming reversible covalent adducts,while displaying high metabolic stability,and imparting improved water solubility to their pendant scaffold. We tested this strategy on the ferroptosis inducer and experimental therapeutic erastin,and observed substantial increases in compound potency. In particular,a new carbonyl erastin analog,termed IKE,displayed improved potency,solubility and metabolic stability,thus representing an ideal candidate for future in vivo cancer therapeutic applications.
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Y. Lai et al. (sep 2020)
Cell systems 11 3 239--251.e7
Illuminating Host-Mycobacterial Interactions with Genome-wide CRISPR Knockout and CRISPRi Screens.
Existing antibiotics are inadequate to defeat tuberculosis (TB),a leading cause of death worldwide. We sought potential targets for host-directed therapies (HDTs) by investigating the host immune response to mycobacterial infection. We used high-throughput CRISPR knockout and CRISPR interference (CRISPRi) screens to identify perturbations that improve the survival of human phagocytic cells infected with Mycobacterium bovis BCG (Bacillus Calmette-Gu{\'{e}}rin),as a proxy for Mycobacterium tuberculosis (Mtb). Many of these perturbations constrained the growth of intracellular mycobacteria. We identified over 100 genes associated with diverse biological pathways as potential HDT targets. We validated key components of the type I interferon and aryl hydrocarbon receptor signaling pathways that respond to the small-molecule inhibitors cerdulatinib and CH223191,respectively; these inhibitors enhanced human macrophage survival and limited the intracellular growth of Mtb. Thus,high-throughput functional genomic screens,by elucidating highly complex host-pathogen interactions,can serve to identify HDTs to potentially improve TB treatment.
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