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1.
European Respiratory Journal ; 60(Supplement 66):3071, 2022.
Article in English | EMBASE | ID: covidwho-2297683

ABSTRACT

Introduction: SARS-CoV-2 tropism for the ACE2 receptor, along with the multifaceted inflammatory reaction, is likely to drive the generalized hypercoagulable state seen in patients with COVID-19. Methodology: Using the original bioinformatic workflow and network medicine approaches we reanalyzed four coronavirus-related expression datasets and performed co-expression analysis focused on thrombosis and ACE2 related genes. We identified microRNAs (miRNAs) which play role in ACE2-related thrombosis in coronavirus infection and further, we validated the expressions of those miRNAs in 79 hospitalized COVID-19 patients and 32 healthy volunteers by PCR and monitored miRNAs patterns during the acute phase of COVID-19, as well as the prognostic potential of these miRNAs as biomarkers. Result(s): We identified EGFR, HSP90AA1, APP, TP53, PTEN, UBC, FN1, ELAVL1 and CALM1 as regulatory genes which could play a pivotal role in COVID-19 related thrombosis. We also found miR-16-5p, miR-27a-3p, Let- 7b-5p and miR-155-5p as regulators in coagulation and thrombosis process. We observed in separate cohort of COVID-19 patients and healthy controls that (i) expression of miR-16-5p, miR-27a-3p and miR-155-5p increased during observation, compared to the baseline measurement;(ii) a low baseline miR-16-5p expression presents predictive utility in assessment of the hospital length of stay or death in follow-up as a composite endpoint (AUC: 0.810, 95% CI, 0.71-0.91, p<0.0001);(iii) low baseline expression of miR-16-5p and diabetes mellitus are independent predictors of increased length of stay or death according to a multivariate analysis (OR: 9.417;95% CI, 2.647-33.506;p=0.0005 and OR: 6.257;95% CI, 1.049- 37.316;p=0.044, respectively). Conclusion(s): This study enabled us to better characterize changes in gene expression and signaling pathways related to COVID-19 thrombosis. In this study we identified, characterized and validated miRNAs which could serve as novel, thrombosis-related biomarkers of the COVID-19, can be used for early stratification of patients and prediction of severity of infection development in an individual. (Figure Presented) .

2.
World Chinese Journal of Digestology ; 30(18):783-794, 2022.
Article in Chinese | EMBASE | ID: covidwho-2254820

ABSTRACT

Metabolic associated fatty liver disease (MAFLD) is a chronic liver disease with the highest incidence in the world, which affects 1/4-1/3 of the world population and has a serious effect on people's health. As is a multi-systemic disease, MAFLD is closely related to the occurrence and prognosis of many diseases. Studies have shown that MAFLD is associated with viral infectious diseases, and their interaction affects the prognosis of the disease. This paper reviews the research progress in this field in recent years.Copyright © The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.

3.
EMBO J ; 42(10): e112234, 2023 05 15.
Article in English | MEDLINE | ID: covidwho-2284890

ABSTRACT

The interferon-induced transmembrane proteins (IFITM) are implicated in several biological processes, including antiviral defense, but their modes of action remain debated. Here, taking advantage of pseudotyped viral entry assays and replicating viruses, we uncover the requirement of host co-factors for endosomal antiviral inhibition through high-throughput proteomics and lipidomics in cellular models of IFITM restriction. Unlike plasma membrane (PM)-localized IFITM restriction that targets infectious SARS-CoV2 and other PM-fusing viral envelopes, inhibition of endosomal viral entry depends on lysines within the conserved IFITM intracellular loop. These residues recruit Phosphatidylinositol 3,4,5-trisphosphate (PIP3) that we show here to be required for endosomal IFITM activity. We identify PIP3 as an interferon-inducible phospholipid that acts as a rheostat for endosomal antiviral immunity. PIP3 levels correlated with the potency of endosomal IFITM restriction and exogenous PIP3 enhanced inhibition of endocytic viruses, including the recent SARS-CoV2 Omicron variant. Together, our results identify PIP3 as a critical regulator of endosomal IFITM restriction linking it to the Pi3K/Akt/mTORC pathway and elucidate cell-compartment-specific antiviral mechanisms with potential relevance for the development of broadly acting antiviral strategies.


Subject(s)
Antiviral Agents , COVID-19 , Humans , Interferons/metabolism , Phospholipids , Phosphatidylinositol 3-Kinases/metabolism , RNA, Viral , RNA-Binding Proteins/metabolism , SARS-CoV-2/metabolism , Virus Internalization , Membrane Proteins/metabolism
4.
Blood ; 138:868, 2021.
Article in English | EMBASE | ID: covidwho-1582312

ABSTRACT

Background: Within seconds of antigen-encounter, B-cell receptor (BCR) signaling induces dramatic changes of cell membrane lipid composition, including >40-fold increases of local PIP3-concentrations within lipid rafts. While several structural elements, including pleckstrin homology (PH) domains have been identified as PIP3-binding proteins, the underlying mechanisms that amplify BCR-signaling to assemble large signaling complexes within lipid rafts within 15 to 30 seconds, remained elusive. To understand the mechanistic and biophysical requirements for PIP3 accumulation during normal B-cell activation and acute oncogenic transformation, we identified PIP3-interacting proteins by cell-surface proteomic analyses. Results: In addition to proteins known to bind PIP3 with their PH-domains, we identified the short 133 aa protein IFITM3 (interferon-inducible transmembrane protein 3) as a top-ranking PIP3 scaffold. This was unexpected because IFITM3 was previously identified as endosomal protein that blocks viral infection by stiffening endosomal membranes to firmly contain viral cargo. Previous studies revealed that polymorphisms that lead to the expression of truncated IFITM3 are associated with increased susceptibility to viral infections, including SARS-CoV2. Among known cell membrane lipids, PIP3 has the highest negative charge. Instead of a PH-domain, IFITM3 laterally sequestered PIP3 through electrostatic interactions with two basic lysine residues (K83 and K104) located at the membrane-solution interface. Together with three other basic lysine and arginine residues K83 and K104 form a conserved intracellular loop (CIL), which enable IFITM3 to efficiently capture two PIP3 molecules. Bivalent PIP3-binding of the IFITM3-CIL enables a crosslinking mechanism that results in dramatic amplification of B-cell activation signals and clustering of large signaling complexes within lipid rafts. In normal resting B-cells, Ifitm3 was minimally expressed and mainly localized in endosomes. However, B-cell activation and oncogenic kinases induced phosphorylation at IFITM3-Y20, resulting in translocation of IFITM3 from endosomes and massive accumulation at the cell surface. Ifitm3ˉ /ˉ naïve B-cells developed at normal numbers, however, activation by antigen encounter was compromised. In Ifitm3ˉ /ˉ B-cells, lipid rafts were depleted of PIP3, resulting in defective expression of >60 lipid raft-associated surface receptors and impaired PI3K-signaling. Ifitm3ˉ /ˉ B-cells were unable to undergo affinity maturation and di not contribute to germinal center formation upon immunization. Analyses of gene expression and clinical outcome data from patients in six clinical cohorts for pediatric and adult B-ALL, mantle cell lymphoma, CLL and DLBCL, we consistently identified IFITM3 as a top-ranking predictor of poor clinical outcome. Inducible activation of BCR-ABL1 and NRAS G12D rapidly induced development of B-ALL but failed to transform and initiate B-ALL from Ifitm3ˉ /ˉ B-cell precursors. Conversely, the phospho-mimetic IFITM3-Y20E mutation, mimicking phosphorylation of the IFITM3 N-terminus at Y20 induced constitutive membrane localization of IFITM3, spontaneous aggregation of large oncogenic signaling complexes and readily initiated transformation in a genetic model of pre-malignant B-cells. Conclusions: We conclude that phosphorylation of IFITM3 upon B-cell activation induces a dynamic switch from antiviral effector functions in endosomes to oncogenic signal-amplification at the cell-surface. IFITM3-dependent amplification of PI3K-signaling is critical to enable rapid expansion of activated B-cells. In addition, multiple oncogenes depend on IFITM3 to assemble PIP3-dependent signaling complexes and amplify PI3K-signaling for malignant transformation and initiation of B-lymphoid leukemia and lymphoma. [Formula presented] Disclosures: Weinstock: SecuraBio: Consultancy;ASELL: Consultancy;Bantam: Consultancy;Abcuro: Research Funding;Verastem: Research Funding;Daiichi Sankyo: Consultancy, Research Funding;AstraZeneca: Consultanc ;Travera: Other: Founder/Equity;Ajax: Other: Founder/Equity.

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