18 research outputs found

    Transcriptional profiling of leukocytes in critically ill COVID19 patients: implications for interferon response and coagulation

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    BACKGROUND: COVID19 is caused by the SARS-CoV-2 virus and has been associated with severe inflammation leading to organ dysfunction and mortality. Our aim was to profile the transcriptome in leukocytes from critically ill patients positive for COVID19 compared to those negative for COVID19 to better understand the COVID19-associated host response. For these studies, all patients admitted to our tertiary care intensive care unit (ICU) suspected of being infected with SARS-CoV-2, using standardized hospital screening methodologies, had blood samples collected at the time of admission to the ICU. Transcriptome profiling of leukocytes via ribonucleic acid sequencing (RNAseq) was then performed and differentially expressed genes as well as significantly enriched gene sets were identified. RESULTS: We enrolled seven COVID19 + (PCR positive, 2 SARS-CoV-2 genes) and seven age- and sex-matched COVID19- (PCR negative) control ICU patients. Cohorts were well-balanced with the exception that COVID19- patients had significantly higher total white blood cell counts and circulating neutrophils and COVID19 + patients were more likely to suffer bilateral pneumonia. The mortality rate for this cohort of COVID19 + ICU patients was 29%. As indicated by both single-gene based and gene set (GSEA) approaches, the major disease-specific transcriptional responses of leukocytes in critically ill COVID19 + ICU patients were: (i) a robust overrepresentation of interferon-related gene expression; (ii) a marked decrease in the transcriptional level of genes contributing to general protein synthesis and bioenergy metabolism; and (iii) the dysregulated expression of genes associated with coagulation, platelet function, complement activation, and tumour necrosis factor/interleukin 6 signalling. CONCLUSIONS: Our findings demonstrate that critically ill COVID19 + patients on day 1 of admission to the ICU display a unique leukocyte transcriptional profile that distinguishes them from COVID19- patients, providing guidance for future targeted studies exploring novel prognostic and therapeutic aspects of COVID19

    Molecular Mechanisms and Treatment Strategies for Dupuytren\u27s Disease

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    Dupuytren\u27s disease (DD) is a common disease of the hand and is characterized by thickening of the palmar fascia and formation of tight collagenous disease cords. At present, the disease is incurable and the molecular pathophysiology of DD is unknown. Surgery remains the most commonly used treatment for DD, but this requires extensive postoperative therapy and is associated with high rates of recurrence. Over the past decades, more indepth exploration of the molecular basis of DD has raised the hopes of developing new treatment modalities. This paper reviews the clinical presentation and molecular pathophysiology of this disease, as well as current and emerging treatment. It also explores the implications of new findings in the laboratory for future treatment

    An Alternative Kinase Activity Assay for Primary Cultures Derived from Clinical Isolates

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    PURPOSE: The measurement of protein kinase activity is central to understanding the signaling pathways that regulate cellular proliferation and apoptosis in virtually all disease processes. These measurements typically involve either indirect, time consuming assessment methods that require large amounts of sample, such as western immunoblotting, or the use of high maintenance, specialized equipment not typically available to a small clinical research facility. The purpose of this project was to determine if a benchtop Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) unit could be used to detect and directly assess kinase activity of the serine/threonine kinase Akt. METHOD: Biotinylated substrate peptides, predicted to be recognized and phosphorylated by Akt to varying extents, were incubated in crude lysates of primary cells derived directly from clinical isolates. Streptavidin-coated chips were then used to isolate the substrate peptides from the lysates after incubation. Finally SELDI-TOF-MS was used to detect the peptide substrates and identify any changes in mass resulting from phosphorylation. RESULTS: The biotinylated peptide substrates were readily detected and a simple, rapid procedure that allows direct measurement of Akt activity in less than 1 microg of cell lysate in a 2microL volume was developed. Further, a linear correlation between native to phospho-peptide ratios and SELDI-TOF-MS output demonstrated that this approach is semi-quantitative. CONCLUSION: This assay avoids many of the pitfalls associated with the currently available kinase protocols as well as labour-intensive mass-spectrometry analysis by specialist laboratories. We propose that this approach may be a viable alternative for clinical research laboratories aiming to measure the activity of kinases in clinical isolates

    Type-1 Collagen Differentially Alters Beta-catenin Accumulation in Primary Dupuytren\u27s Disease Cord and Adjacent Palmar Fascia Cells

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    Background: Dupuytren\u27s Disease (DD) is a debilitating contractile fibrosis of the palmar fascia characterised by excess collagen deposition, contractile myofibroblast development, increased transforming growth factor-beta levels and beta-catenin accumulation. The aim of this study was to determine if a collagen-enriched environment, similar to in vivo conditions, altered beta-catenin accumulation by primary DD cells in the presence or absence of transforming growth factor-beta. Methods: Primary DD and patient matched, phenotypically normal palmar fascia (PF) cells were cultured in the presence or absence of type-1 collagen and transforming growth factor-beta1. beta-catenin and alpha-smooth muscle actin levels were assessed by western immunoblotting and immunofluorescence microscopy. Results: DD cells display a rapid depletion of cellular beta-catenin not evident in patient-matched PF cells. This effect was not evident in either cell type when cultured in the absence of type-1 collagen. Exogenous addition of transforming growth factor-beta1 to DD cells in collagen culture negates the loss of beta-catenin accumulation. Transforming growth factor-beta1-induced alpha-smooth muscle actin, a marker of myofibroblast differentiation, is attenuated by the inclusion of type-1 collagen in cultures of DD and PF cells. Conclusion: Our findings implicate type-1 collagen as a previously unrecognized regulator of beta-catenin accumulation and a modifier of TGF-beta1 signaling specifically in primary DD cells. These data have implications for current treatment modalities as well as the design of in vitro models for research into the molecular mechanisms of DD

    Wnt Expression Is Not Correlated with β-catenin Dysregulation in Dupuytren\u27s Disease

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    Background: Dupuytren\u27s contracture or disease (DD) is a fibro-proliferative disease of the hand that results in finger flexion contractures. Increased cellular β-catenin levels have been identified as characteristic of this disease. As Wnts are the most widely recognized upstream regulators of cellular β-catenin accumulation, we have examined Wnt gene expression in surgical specimens and in DD-derived primary cell cultures grown in two-dimensional monolayer culture or in three-dimensional FPCL collagen lattice cultures. Results: The Wnt expression profile of patient-matched DD and unaffected control palmar fascia tissue was determined by a variety of complimentary methods; Affymetrix Microarray analysis, specific Wnt and degenerative primer-based Reverse Transcriptase (RT)-PCR, and Real Time PCR. Microarray analysis identified 13 Wnts associated with DD and control tissues. Degenerate Wnt RT-PCR analysis identified Wnts 10b and 11, and to a lesser extent 5a and 9a, as the major Wnt family members expressed in our patient samples. Competitive RT-PCR analysis identified significant differences between the levels of expression of Wnts 9a, 10b and 11 in tissue samples and in primary cell cultures grown as monolayer or in FPCL, where the mRNA levels in tissue \u3e FPCL cultures \u3e monolayer cultures. Real Time PCR data confirmed the down-regulation of Wnt 11 mRNA in DD while Wnt 10b, the most frequently isolated Wnt in DD and control palmar fascia, displayed widely variable expression between the methods of analysis. Conclusion: These data indicate that changes in Wnt expression per se are unlikely to be the cause of the observed dysregulation of β-catenin expression in DD

    Keloid Scarring, but Not Dupuytren\u27s Contracture, Is Associated with Unexplained Carotid Atherosclerosis

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    BACKGROUND: Atherosclerosis, a response to injury, may be thought of as scarring in the artery wall. TGF-beta and associated signaling molecules have been implicated in the pathophysiology of keloid scarring, Dupuytren\u27s Contracture and atherosclerotic plaques in independent studies. PURPOSE: To test the hypothesis that excess cutaneous scarring and Dupuytren\u27s contractures predispose independently to carotid atherosclerosis . METHODS: Among 1,747 patients with plaque measurements and complete data for multivariable regression analysis, 57 Caucasian patients had Dupuytren\u27s contractures and 12 had keloid scars. Carotid total plaque area (TPA) was measured by 2-Dimensional ultrasound. RESULTS: In linear multivariable regression analysis with coronary risk factors, keloid scars were associated with TPA (P= 0.018), but Dupuytren\u27s contractures were not. Patients with keloid scarring were younger (P \u3c 0.0001), and more likely to be diabetic (P \u3c 0.0001) CONCLUSIONS: Keloid scarring is a clinical clue to excess atherosclerosis not explained by traditional risk factors. Such patients may benefit from therapy directed at targets related to signalling molecules common to both the process of keloid scarring and atherosclerosis. These findings suggest previously unexplored possibilities for the prevention and treatment of atherosclerosis. The differences between Dupuytren\u27s and keloid scars that may identify such targets are discussed

    Neer Award 2017: A rapid method for detecting Propionibacterium acnes in surgical biopsy specimens from the shoulder

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    © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees Background Propionibacterium (P) acnes infection of the shoulder after arthroplasty is a common and serious complication. Current detection methods for P acnes involve anaerobic cultures that require prolonged incubation periods (typically 7-14 days). We have developed a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) approach that sensitively and specifically identifies P acnes in tissue specimens within a 24-hour period. Methods Primers were designed to amplify a unique region of the 16S rRNA gene in P acnes that contained a unique HaeIII restriction enzyme site. PCR and RFLP analyses were optimized to detect P acnes DNA in in vitro cultures and in arthroscopic surgical biopsy specimens from patients with P acnes infections. Results A 564 base-pair PCR amplicon was derived from all of the known P acnes strains. HaeIII digests of the amplicon yielded a restriction fragment pattern that was unique to P acnes. P acnes-specific amplicons were detected in as few as 10 bacterial cells and in clinical biopsy specimens of infected shoulder tissues. Conclusion This PCR-RFLP assay combines the sensitivity of PCR with the specificity of RFLP mapping to identify P acnes in surgical isolates. The assay is robust and rapid, and a P acnes-positive tissue specimen can be confirmed within 24 hours of sampling, facilitating treatment decision making, targeted antibiotic therapy, and monitoring to minimize implant failure and revision surgery

    Protein Biomarker Analysis of Primary Peyronie\u27s Disease Cells

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    INTRODUCTION: The molecular pathogenesis of Peyronie\u27s Disease (PD) remains unclear more than 250 years after its initial description. Because of this, no test is currently available to accurately predict PD progression among those affected. AIM: To investigate the expression of wound healing and fibrosis-associated proteins in primary cell cultures of PD fibroblasts to determine whether altered protein expression patterns can be used as predictors of clinical course and natural history. METHODS: Primary cell cultures derived from normal Tunica albuginea tissue and PD plaque tissue were examined by immuno-cytochemistry. Protein expression profiles were analyzed by Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS) and Western immunoblotting. MAIN OUTCOME MEASURES: Expression of wound healing and fibrosis-associated proteins and protein expression patterns were assessed. RESULTS: Statistically significant increases in smooth muscle alpha-actin, beta-catenin, and Heat shock proteins (Hsp47) were identified in cells derived from PD relative to cells derived from normal Tunica albuginea tissue. Changes in TGFbeta-1 receptor and Fibronectin were also observed. In addition, altered expression of additional as yet unidentified proteins at 4.7, 8.9, 10.8, 16.8, and 76.8 kDa were detected by complementary SELDI-TOF-MS approaches. CONCLUSIONS: Primary cells derived from PD plaques display up-regulated expression of several proteins that are established components of fibrosis and wound healing. In addition, changes in other, as yet unidentified proteins were measured. It will be of interest to conduct further studies to see whether these dysregulated protein peaks represent potential biological markers of disease progression

    Periostin Differentially Induces Proliferation, Contraction and Apoptosis of Primary Dupuytren\u27s Disease and Adjacent Palmar Fascia Cells

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    Dupuytren\u27s disease, (DD), is a fibroproliferative condition of the palmar fascia in the hand, typically resulting in permanent contracture of one or more fingers. This fibromatosis is similar to scarring and other fibroses in displaying excess collagen secretion and contractile myofibroblast differentiation. In this report we expand on previous data demonstrating that POSTN mRNA, which encodes the extra-cellular matrix protein periostin, is up-regulated in Dupuytren\u27s disease cord tissue relative to phenotypically normal palmar fascia. We demonstrate that the protein product of POSTN, periostin, is abundant in Dupuytren\u27s disease cord tissue while little or no periostin immunoreactivity is evident in patient-matched control tissues. The relevance of periostin up-regulation in DD was assessed in primary cultures of cells derived from diseased and phenotypically unaffected palmar fascia from the same patients. These cells were grown in type-1 collagen-enriched culture conditions with or without periostin addition to more closely replicate the in vivo environment. Periostin was found to differentially regulate the apoptosis, proliferation, alpha smooth muscle actin expression and stressed Fibroblast Populated Collagen Lattice contraction of these cell types. We hypothesize that periostin, secreted by disease cord myofibroblasts into the extra-cellular matrix, promotes the transition of resident fibroblasts in the palmar fascia toward a myofibroblast phenotype, thereby promoting disease progression
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