36 research outputs found
Norovirus Replication in Human Intestinal Epithelial Cells Is Restricted by the Interferon-Induced JAK/STAT Signaling Pathway and RNA Polymerase II-Mediated Transcriptional Responses.
Human noroviruses (HuNoV) are a leading cause of viral gastroenteritis worldwide and a significant cause of morbidity and mortality in all age groups. The recent finding that HuNoV can be propagated in B cells and mucosa-derived intestinal epithelial organoids (IEOs) has transformed our ability to dissect the life cycle of noroviruses. Using transcriptome sequencing (RNA-Seq) of HuNoV-infected intestinal epithelial cells (IECs), we have found that replication of HuNoV in IECs results in interferon (IFN)-induced transcriptional responses and that HuNoV replication in IECs is sensitive to IFN. This contrasts with previous studies that suggested that the innate immune response may play no role in the restriction of HuNoV replication in immortalized cells. We demonstrated that inhibition of Janus kinase 1 (JAK1)/JAK2 enhanced HuNoV replication in IECs. Surprisingly, targeted inhibition of cellular RNA polymerase II-mediated transcription was not detrimental to HuNoV replication but instead enhanced replication to a greater degree than blocking of JAK signaling directly. Furthermore, we demonstrated for the first time that IECs generated from genetically modified intestinal organoids, engineered to be deficient in the interferon response, were more permissive to HuNoV infection. Taking the results together, our work revealed that IFN-induced transcriptional responses restrict HuNoV replication in IECs and demonstrated that inhibition of these responses mediated by modifications of the culture conditions can greatly enhance the robustness of the norovirus culture system.IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide, and yet the challenges associated with their growth in culture have greatly hampered the development of therapeutic approaches and have limited our understanding of the cellular pathways that control infection. Here, we show that human intestinal epithelial cells, which represent the first point of entry of human noroviruses into the host, limit virus replication by induction of innate responses. Furthermore, we show that modulating the ability of intestinal epithelial cells to induce transcriptional responses to HuNoV infection can significantly enhance human norovirus replication in culture. Collectively, our findings provide new insights into the biological pathways that control norovirus infection but also identify mechanisms that enhance the robustness of norovirus culture
Nlrp3 inflammasome activation and Gasdermin D-driven pyroptosis are immunopathogenic upon gastrointestinal norovirus infection.
Norovirus infection is the leading cause of food-borne gastroenteritis worldwide, being responsible for over 200,000 deaths annually. Studies with murine norovirus (MNV) showed that protective STAT1 signaling controls viral replication and pathogenesis, but the immune mechanisms that noroviruses exploit to induce pathology are elusive. Here, we show that gastrointestinal MNV infection leads to widespread IL-1β maturation in MNV-susceptible STAT1-deficient mice. MNV activates the canonical Nlrp3 inflammasome in macrophages, leading to maturation of IL-1β and to Gasdermin D (GSDMD)-dependent pyroptosis. STAT1-deficient macrophages displayed increased MAVS-mediated expression of pro-IL-1β, facilitating elevated Nlrp3-dependent release of mature IL-1β upon MNV infection. Accordingly, MNV-infected Stat1-/- mice showed Nlrp3-dependent maturation of IL-1β as well as Nlrp3-dependent pyroptosis as assessed by in vivo cleavage of GSDMD to its active N-terminal fragment. While MNV-induced diarrheic responses were not affected, Stat1-/- mice additionally lacking either Nlrp3 or GSDMD displayed lower levels of the fecal inflammatory marker Lipocalin-2 as well as delayed lethality after gastrointestinal MNV infection. Together, these results uncover new insights into the mechanisms of norovirus-induced inflammation and cell death, thereby revealing Nlrp3 inflammasome activation and ensuing GSDMD-driven pyroptosis as contributors to MNV-induced immunopathology in susceptible STAT1-deficient mice.Wellcome Trust
BBSR
Norovirus-Mediated Modification of the Translational Landscape via Virus and Host-Induced Cleavage of Translation Initiation Factors
Feline Calicivirus Infection Disrupts Assembly of Cytoplasmic Stress Granules and Induces G3BP1 Cleavage.
UNLABELLED: In response to stress such as virus infection, cells can stall translation by storing mRNAs away in cellular compartments called stress granules (SGs). This defense mechanism favors cell survival by limiting the use of energy and nutrients until the stress is resolved. In some cases it may also block viral propagation as viruses are dependent on the host cell resources to produce viral proteins. Human norovirus is a member of the Caliciviridae family responsible for gastroenteritis outbreaks worldwide. Previous studies on caliciviruses have identified mechanisms by which they can usurp the host translational machinery, using the viral protein genome-linked VPg, or regulate host protein synthesis through the mitogen-activated protein kinase (MAPK) pathway. Here, we examined the effect of feline calicivirus (FCV) infection on SG accumulation. We show that FCV infection impairs the assembly of SGs despite an increased phosphorylation of eukaryotic initiation factor eIF2Îą, a hallmark of stress pathway activation. Furthermore, SGs did not accumulate in FCV-infected cells that were stressed with arsenite or hydrogen peroxide. FCV infection resulted in the cleavage of the SG-nucleating protein Ras-GTPase activating SH3 domain-binding protein (G3BP1), which is mediated by the viral 3C-like proteinase NS6(Pro) Using mutational analysis, we identified the FCV-induced cleavage site within G3BP1, which differs from the poliovirus 3C proteinase cleavage site previously identified. Finally, we showed that NS6(Pro)-mediated G3BP1 cleavage impairs SG assembly. In contrast, murine norovirus (MNV) infection did not impact arsenite-induced SG assembly or G3BP1 integrity, suggesting that related caliciviruses have distinct effects on the stress response pathway. IMPORTANCE: Human noroviruses are a major cause of viral gastroenteritis, and it is important to understand how they interact with the infected host cell. Feline calicivirus (FCV) and murine norovirus (MNV) are used as models to understand norovirus biology. Recent studies have suggested that the assembly of stress granules is central in orchestrating stress and antiviral responses to restrict viral replication. Overall, our study provides the first insight on how caliciviruses impair stress granule assembly by targeting the nucleating factor G3BP1 via the viral proteinase NS6(Pro) This work provides new insights into host-pathogen interactions that regulate stress pathways during FCV infection
Proceedings of the International Cancer Imaging Society (ICIS) 16th Annual Teaching Course
Table of contents
O1 Tumour heterogeneity: what does it mean?
Dow-Mu Koh
O2 Skeletal sequelae in adult survivors of childhood cancer
Sue Creviston Kaste
O3 Locoregional effects of breast cancer treatment
Sarah J Vinnicombe
O4 Imaging of cancer therapy-induced CNS toxicity
Giovanni Morana, Andrea Rossi
O5 Screening for lung cancer
Christian J. Herold
O6Risk stratification of lung nodules
Theresa C. McLoud
O7 PET imaging of pulmonary nodules
Kirk A Frey
O8 Transarterial tumour therapy
Bernhard Gebauer
O9 Interventional radiology in paediatric oncology
Derek Roebuck
O10 Image guided prostate interventions
Jurgen J. FĂźtterer
O11 Imaging cancer predisposition syndromes
Alexander J. Towbin
O12Chest and chest wall masses
Thierry AG Huisman
O13 Abdominal masses: good or bad?
Anne MJB Smets
O14 Hepatobiliary MR contrast: enhanced liver MRI for HCC diagnosis and management
Giovanni Morana
O15 Role of US elastography and multimodality fusion for managing patients with chronic liver disease and HCC
Jeong Min Lee
O16 Opportunities and challenges in imaging metastatic disease
Hersh Chandarana
O17 Diagnosis, treatment monitoring, and follow-up of lymphoma
Marius E. Mayerhoefer, Markus Raderer, Alexander Haug
O18 Managing high-risk and advanced prostate cancer
Matthias Eiber
O19 Immunotherapy: imaging challenges
Bernhard Gebauer
O20 RECIST and RECIST 1.1
Andrea Rockall
O21 Challenges of RECIST in oncology imaging basics for the trainee and novice
Aslam Sohaib
O22 Lymphoma: PET for interim and end of treatment response assessment: a usersâ guide to the Deauville Score
Victoria S Warbey
O23 Available resources
Hebert Alberto Vargas
O24 ICIS e-portal and the online learning community
Dow-Mu Koh
O25 Benign lesions that mimic pancreatic cancer
Jay P Heiken
O26 Staging and reporting pancreatic malignancies
Isaac R Francis, Mahmoud, M Al-Hawary, Ravi K Kaza
O27 Intraductal papillary mucinous neoplasm
Giovanni Morana
O28 Cystic pancreatic tumours
Mirko DâOnofrio
O29 Diffusion-weighted imaging of head and neck tumours
Harriet C. Thoeny
O30 Radiation injury in the head and neck
Ann D King
O31 PET/MR of paediatric brain tumours
Giovanni Morana, Arnoldo Piccardo, Maria Luisa Garrè, Andrea Rossi
O32 Structured reporting and beyond
Hebert Alberto Vargas
O33 Massachusetts General Hospital experience with structured reporting
Theresa C. McLoud
O34 The oncologistâs perspective: what the oncologist needs to know
Nick Reed
O35 Towards the cure of all children with cancer: global initiatives in pediatric oncology
Carlos Rodriguez-Galindo
O36 Multiparametric imaging of renal cancers
Hersh Chandarana
O37 Linking imaging features of renal disease and their impact on management strategies
Hebert Alberto Vargas
O38 Adrenals, retroperitoneum and peritoneum
Isaac R Francis, Ashish P Wasnik
O39 Lung and pleura
Stefan Diederich
O40 Advances in MRI
Jurgen J. FĂźtterer
O41 Advances in molecular imaging
Wim J.G. Oyen
O42 Incorporating advanced imaging, impact on treatment selection and patient outcome
Cheng Lee Chaw, Nicholas van As
S1 Combining ADC-histogram features improves performance of MR diffusion-weighted imaging for Lymph node characterisation in cervical cancer
Igor Vieira, Frederik De Keyzer, Elleke Dresen, Sileny Han, Ignace Vergote, Philippe Moerman, Frederic Amant, Michel Koole, Vincent Vandecaveye
S2 Whole-body diffusion-weighted MRI for surgical planning in patients with colorectal cancer and peritoneal metastases
R Dresen, S De Vuysere, F De Keyzer, E Van Cutsem, A DâHoore, A Wolthuis, V Vandecaveye
S3 Role of apparent diffusion coefficient (ADC) diffusion-weighted MRI for predicting extra capsular extension of prostate cancer.
P. Pricolo ([email protected]), S. Alessi, P. Summers, E. Tagliabue, G. Petralia
S4 Generating evidence for clinical benefit of PET/CT â are management studies sufficient as surrogate for patient outcome?
C. Pfannenberg, B. GĂźckel, SC SchĂźle, AC MĂźller, S. Kaufmann, N. Schwenzer, M. Reimold,C. la Fougere, K. Nikolaou, P. Martus
S5 Heterogeneity of treatment response in skeletal metastases from breast cancer with 18F-fluoride and 18F-FDG PET
GJ Cook, GK Azad, BP Taylor, M Siddique, J John, J Mansi, M Harries, V Goh
S6 Accuracy of suspicious breast imagingâcan we tell the patient?
S Seth, R Burgul, A Seth
S7 Measurement method of tumour volume changes during neoadjuvant chemotherapy affects ability to predict pathological response
S Waugh, N Muhammad Gowdh, C Purdie, A Evans, E Crowe, A Thompson, S Vinnicombe
S8 Diagnostic yield of CT IVU in haematuria screening
F. Arfeen, T. Campion, E. Goldstraw
S9 Percutaneous radiofrequency ablation of unresectable locally advanced pancreatic cancer: preliminary results
DâOnofrio M, Ciaravino V, Crosara S, De Robertis R, Pozzi Mucelli R
S10 Iodine maps from dual energy CT improve detection of metastases in staging examinations of melanoma patients
M. Uhrig, D. Simons, H. Schlemmer
S11Can contrast enhanced CT predict pelvic nodal status in malignant melanoma of the lower limb?
Kate Downey
S12 Current practice in the investigation for suspected Paraneoplastic Neurological Syndromes (PNS) and positive malignancy yield.
S Murdoch, AS Al-adhami, S Viswanathan
P1 Technical success and efficacy of Pulmonary Radiofrequency ablation: an analysis of 207 ablations
S Smith, P Jennings, D Bowers, R Soomal
P2 Lesion control and patient outcome: prospective analysis of radiofrequency abaltion in pulmonary colorectal cancer metastatic disease
S Smith, P Jennings, D Bowers, R Soomal
P3 Hepatocellular carcinoma in a post-TB patient: case of tropical infections and oncologic imaging challenges
TM Mutala, AO Odhiambo, N Harish
P4 Role of apparent diffusion coefficient (ADC) diffusion-weighted MRI for predicting extracapsular extension of prostate cancer
P. Pricolo, S. Alessi, P. Summers, E. Tagliabue, G. Petralia
P5 What a difference a decade makes; comparison of lung biopsies in Glasgow 2005 and 2015
M. Hall, M. Sproule, S. Sheridan
P6 Solid pseudopapillary tumour of pancreas: imaging features of a rare neoplasm
KY Thein, CH Tan, YL Thian, CM Ho
P7 MDCT - pathological correlation in colon adenocarcinoma staging: preliminary experience
S De Luca, C Carrera, V Blanchet, L AlarcĂłn, E Eyheremnedy
P8 Image guided biopsy of thoracic masses and reduction of pneumothorax risk: 25Â years experience
B K Choudhury, K Bujarbarua, G Barman
P9 Tumour heterogeneity analysis of 18F-FDG-PET for characterisation of malignant peripheral nerve sheath tumours in neurofibromatosis-1
GJ Cook, E Lovat, M Siddique, V Goh, R Ferner, VS Warbey
P10 Impact of introduction of vacuum assisted excision (VAE) on screen detected high risk breast lesions
L Potti, B Kaye, A Beattie, K Dutton
P11 Can we reduce prevalent recall rate in breast screening?
AA Seth, F Constantinidis, H Dobson
P12 How to reduce prevalent recall rate? Identifying mammographic lesions with low Positive Predictive Value (PPV)
AA Seth ([email protected]), F Constantinidis, H Dobson
P13 Behaviour of untreated pulmonary thrombus in oncology patients diagnosed with incidental pulmonary embolism on CT
R. Bradley, G. Bozas, G. Avery, A. Stephens, A. Maraveyas
P14 A one-stop lymphoma biopsy service â is it possible?
S Bhuva, CA Johnson, M Subesinghe, N Taylor
P15 Changes in the new TNM classification for lung cancer (8th edition, effective January 2017)
LE Quint, RM Reddy, GP Kalemkerian
P16 Cancer immunotherapy: a review of adequate imaging assessment
G GonzĂĄlez Zapico, E Gainza Jauregui, R Ălvarez Francisco, S IbĂĄĂąez Alonso, I Tavera Bahillo, L MĂşgica Ălvarez
P17 Succinate dehydrogenase mutations and their associated tumours
O Francies, R Wheeler, L Childs, A Adams, A Sahdev
P18 Initial experience in the usefulness of dual energy technique in the abdomen
SE De Luca, ME Casalini VaĂąek, MD Pascuzzi, T Gillanders, PM Ramos, EP Eyheremendy
P19 Recognising the serious complication of Richterâs transformation in CLL patients
C Stove, M Digby
P20 Body diffusion-weighted MRI in oncologic practice: truths, tricks and tips
M. Nazar, M. Wirtz, MD. Pascuzzi, F. Troncoso, F. Saguier, EP. Eyheremendy
P21 Methotrexate-induced leukoencephalopathy in paediatric ALL Patients
D.J. Quint, L. Dang, M. Carlson, S. Leber, F. Silverstein
P22 Pitfalls in oncology CT reporting. A pictorial review
R Rueben, S Viswanathan
P23 Imaging of perineural extension in head and neck tumours
B Nazir, TH Teo, JB Khoo
P24 MRI findings of molecular subtypes of breast cancer: a pictorial primer
K Sharma, N Gupta, B Mathew, T Jeyakumar, K Harkins
P25 When cancer canât wait! A pictorial review of oncological emergencies
K Sharma, B Mathew, N Gupta, T Jeyakumar, S Joshua
P26 MRI of pancreatic neuroendocrine tumours: an approach to interpretation
D Christodoulou, S Gourtsoyianni, A Jacques, N Griffin, V Goh
P27 Gynaecological cancers in pregnancy: a review of imaging
CA Johnson, J Lee
P28 Suspected paraneoplastic neurological syndromes - review of published recommendations to date, with proposed guideline/flowchart
JA Goodfellow, AS Al-adhami, S Viswanathan
P29 Multi-parametric MRI of the pelvis for suspected local recurrence of prostate cancer after radical prostatectomy
R Bradley
P30 Utilisation of PI-RADS version 2 in multi-parametric MRI of the prostate; 12-months experience
R Bradley
P31 Radiological assessment of the post-chemotherapy liver
A Yong, S Jenkins, G Joseph
P32 Skeletal staging with MRI in breast cancer â what the radiologist needs to know
S Bhuva, K Partington
P33 Perineural spread of lympoma: an educational review of an unusual distribution of disease
CA Johnson, S Bhuva, M Subesinghe, N Taylor
P34 Visually isoattenuating pancreatic adenocarcinoma. Diagnostic imaging tools.
C Carrera, A Zanfardini, S De Luca, L AlarcĂłn, V Blanchet, EP Eyheremendy
P35 Imaging of larynx cancer: when is CT, MRI or FDG PET/CT the best test?
K Cavanagh, E Lauhttp://deepblue.lib.umich.edu/bitstream/2027.42/134651/1/40644_2016_Article_79.pd
Minimally invasive total knee replacement : techniques and results
In this review, we outlined the definition of minimally invasive surgery (MIS) in total knee replacement (TKR) and described the different surgical approaches reported in the literature. Afterwards we went through the most recent studies assessing MIS TKR. Next, we searched for potential limitations of MIS knee replacement and tried to answer the following questions: Are there selective criteria and specific patient selection for MIS knee surgery? If there are, then what are they? After all, a discussion and conclusion completed this article. There is certainly room for MIS or at least less invasive surgery (LIS) for appropriate selected patients. Nonetheless, there are differences between approaches. Mini medial parapatellar is easy to master, quick to perform and potentially extendable, whereas mini subvastus and mini midvastus are trickier and require more caution related to risk of hematoma and VMO nerve damage. Current evidence on the safety and efficacy of mini-incision surgery for TKR does not appear fully adequate for the procedure to be used without special arrangements for consent and for audit or continuing research. There is an argument that a sudden jump from standard TKR to MIS TKR, especially without computer assistance such as navigation, patient specific instrumentation (PSI) or robotic, may breach a surgeon's duty of care toward patients because it exposes patients to unnecessary risks. As a final point, more evidence is required on the long-term safety and efficacy of this procedure which will give objective shed light on real benefits of MIS TKR
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An optimized protocol for the extraction and quantification of cytosolic DNA in mammalian cells
Leakage of mitochondrial or nuclear DNA into the cytosol can occur following viral infections, radiation damage, and in some cancers. Here, we present an optimized protocol for isolating and quantifying cytosolic DNA from mammalian cells. We describe steps for collecting cytosolic fractions from cells, extracting DNA using columns, and quantifying extracted DNA using qPCR. This straightforward protocol can be completed in as little as 5 hours, and allows for identification of the source of DNA
An optimized protocol for the extraction and quantification of cytosolic DNA in mammalian cells
Summary: Leakage of mitochondrial or nuclear DNA into the cytosol can occur following viral infections, radiation damage, and some cancers. Here, we present an optimized protocol for isolating and quantifying cytosolic DNA from mammalian cells. We describe steps for collecting cytosolic fractions from cells, extracting DNA using columns, and quantifying extracted DNA using qPCR. This straightforward protocol can be completed in as little as 5 hours, and allows for the identification of the source of DNA.For complete details on the use and execution of this protocol, please refer to Jahun et al.1 : Publisherâs note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics
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Norovirus Replication in Human Intestinal Epithelial Cells Is Restricted by the Interferon-Induced JAK/STAT Signaling Pathway and RNA Polymerase II-Mediated Transcriptional Responses.
Human noroviruses (HuNoV) are a leading cause of viral gastroenteritis worldwide and a significant cause of morbidity and mortality in all age groups. The recent finding that HuNoV can be propagated in B cells and mucosa-derived intestinal epithelial organoids (IEOs) has transformed our ability to dissect the life cycle of noroviruses. Using transcriptome sequencing (RNA-Seq) of HuNoV-infected intestinal epithelial cells (IECs), we have found that replication of HuNoV in IECs results in interferon (IFN)-induced transcriptional responses and that HuNoV replication in IECs is sensitive to IFN. This contrasts with previous studies that suggested that the innate immune response may play no role in the restriction of HuNoV replication in immortalized cells. We demonstrated that inhibition of Janus kinase 1 (JAK1)/JAK2 enhanced HuNoV replication in IECs. Surprisingly, targeted inhibition of cellular RNA polymerase II-mediated transcription was not detrimental to HuNoV replication but instead enhanced replication to a greater degree than blocking of JAK signaling directly. Furthermore, we demonstrated for the first time that IECs generated from genetically modified intestinal organoids, engineered to be deficient in the interferon response, were more permissive to HuNoV infection. Taking the results together, our work revealed that IFN-induced transcriptional responses restrict HuNoV replication in IECs and demonstrated that inhibition of these responses mediated by modifications of the culture conditions can greatly enhance the robustness of the norovirus culture system.IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide, and yet the challenges associated with their growth in culture have greatly hampered the development of therapeutic approaches and have limited our understanding of the cellular pathways that control infection. Here, we show that human intestinal epithelial cells, which represent the first point of entry of human noroviruses into the host, limit virus replication by induction of innate responses. Furthermore, we show that modulating the ability of intestinal epithelial cells to induce transcriptional responses to HuNoV infection can significantly enhance human norovirus replication in culture. Collectively, our findings provide new insights into the biological pathways that control norovirus infection but also identify mechanisms that enhance the robustness of norovirus culture