1
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Shen Y, Lin S, You P, Chen Y, Luo Y, Song X, Chen Y, Jin D. Rapid discrimination between clinical Clostridioides difficile infection and colonization by quantitative detection of TcdB toxin using a real-time cell analysis system. Front Microbiol 2024; 15:1348892. [PMID: 38322317 PMCID: PMC10844495 DOI: 10.3389/fmicb.2024.1348892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/08/2024] [Indexed: 02/08/2024] Open
Abstract
Objectives It is important to accurately discriminate between clinical Clostridioides difficile infection (CDI) and colonization (CDC) for effective antimicrobial treatment. Methods In this study, 37 stool samples were collected from 17 CDC and 20 CDI cases, and each sample were tested in parallel through the real-time cell analysis (RTCA) system, real-time PCR assay (PCR), and enzyme-linked immunosorbent assay (ELISA). Results RTCA-measured functional and toxical C. difficile toxin B (TcdB) concentrations in the CDI group (302.58 ± 119.15 ng/mL) were significantly higher than those in the CDC group (18.15 ± 11.81 ng/mL) (p = 0.0008). Conversely, ELISA results revealed no significant disparities in TcdB concentrations between the CDC (26.21 ± 3.57 ng/mL) and the CDI group (17.07 ± 3.10 ng/mL) (p = 0.064). PCR results indicated no significant differences in tcdB gene copies between the CDC (774.54 ± 357.89 copies/μL) and the CDI group (4,667.69 ± 3,069.87 copies/μL) (p = 0.407). Additionally, the functional and toxical TcdB concentrations secreted from C. difficile isolates were measured by the RTCA. The results from the CDC (490.00 ± 133.29 ng/mL) and the CDI group (439.82 ± 114.66 ng/mL) showed no significant difference (p = 0.448). Notably, RTCA-measured functional and toxical TcdB concentration was significantly decreased when mixed with pooled CDC samples supernatant (p = 0.030). Conclusion This study explored the novel application of the RTCA assay in effectively discerning clinical CDI from CDC cases.
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Affiliation(s)
- Yuhang Shen
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, China
- Institute of Ageing Research, School of Basic Medical Sciences, Hangzhou Normal University, Hangzhou, China
| | - Shan Lin
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, China
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, Tianjin, China
| | - Peijun You
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, China
| | - Yu Chen
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, China
| | - Yun Luo
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Xiaojun Song
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Hangzhou Medical College, Hangzhou, China
| | - Yunbo Chen
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Dazhi Jin
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, China
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Hangzhou Medical College, Hangzhou, China
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2
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Kordus SL, Kroh HK, Rodríguez RC, Shrem RA, Peritore-Galve FC, Shupe JA, Wadzinski BE, Lacy DB, Spiller BW. Nanobodies against C. difficile TcdA and TcdB reveal unexpected neutralizing epitopes and provide a toolkit for toxin quantitation in vivo. PLoS Pathog 2023; 19:e1011496. [PMID: 37871122 PMCID: PMC10621975 DOI: 10.1371/journal.ppat.1011496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 11/02/2023] [Accepted: 10/07/2023] [Indexed: 10/25/2023] Open
Abstract
Clostridioides difficile is a leading cause of antibiotic-associated diarrhea and nosocomial infection in the United States. The symptoms of C. difficile infection (CDI) are associated with the production of two homologous protein toxins, TcdA and TcdB. The toxins are considered bona fide targets for clinical diagnosis as well as the development of novel prevention and therapeutic strategies. While there are extensive studies that document these efforts, there are several gaps in knowledge that could benefit from the creation of new research tools. First, we now appreciate that while TcdA sequences are conserved, TcdB sequences can vary across the span of circulating clinical isolates. An understanding of the TcdA and TcdB epitopes that drive broadly neutralizing antibody responses could advance the effort to identify safe and effective toxin-protein chimeras and fragments for vaccine development. Further, an understanding of TcdA and TcdB concentration changes in vivo can guide research into how host and microbiome-focused interventions affect the virulence potential of C. difficile. We have developed a panel of alpaca-derived nanobodies that bind specific structural and functional domains of TcdA and TcdB. We note that many of the potent neutralizers of TcdA bind epitopes within the delivery domain, a finding that could reflect roles of the delivery domain in receptor binding and/or the conserved role of pore-formation in the delivery of the toxin enzyme domains to the cytosol. In contrast, neutralizing epitopes for TcdB were found in multiple domains. The nanobodies were also used for the creation of sandwich ELISA assays that allow for quantitation of TcdA and/or TcdB in vitro and in the cecal and fecal contents of infected mice. We anticipate these reagents and assays will allow researchers to monitor the dynamics of TcdA and TcdB production over time, and the impact of various experimental interventions on toxin production in vivo.
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Affiliation(s)
- Shannon L. Kordus
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Heather K. Kroh
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rubén Cano Rodríguez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rebecca A. Shrem
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - F. Christopher Peritore-Galve
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - John A. Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brian E. Wadzinski
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
| | - Benjamin W. Spiller
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
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3
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Huber A, Jose S, Kassam A, Weghorn KN, Powers-Fletcher M, Sharma D, Mukherjee A, Mathew A, Kulkarni N, Chandramouli S, Alder MN, Madan R. Olfactomedin-4 + neutrophils exacerbate intestinal epithelial damage and worsen host survival after Clostridioides difficile infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.21.553751. [PMID: 37662327 PMCID: PMC10473617 DOI: 10.1101/2023.08.21.553751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Neutrophils are key first responders to Clostridioides difficile infection (CDI). Excessive tissue and blood neutrophils are associated with worse histopathology and adverse outcomes, however their functional role during CDI remains poorly defined. Utilizing intestinal epithelial cell (IEC)-neutrophil co-cultures and a pre-clinical animal model of CDI, we show that neutrophils exacerbate C. difficile -induced IEC injury. We utilized cutting-edge single-cell transcriptomics to illuminate neutrophil subtypes and biological pathways that could exacerbate CDI-associated IEC damage. As such, we have established the first transcriptomics atlas of bone marrow (BM), blood, and colonic neutrophils after CDI. We found that CDI altered the developmental trajectory of BM and blood neutrophils towards populations that exhibit gene signatures associated with pro-inflammatory responses and neutrophil-mediated tissue damage. Similarly, the transcriptomic signature of colonic neutrophils was consistent with hyper-inflammatory and highly differentiated cells that had amplified expression of cytokine-mediated signaling and degranulation priming genes. One of the top 10 variable features in colonic neutrophils was the gene for neutrophil glycoprotein, Olfactomedin 4 (OLFM4). CDI enhanced OLFM4 mRNA and protein expression in neutrophils, and OLFM4 + cells aggregated to areas of severe IEC damage. Compared to uninfected controls, both humans and mice with CDI had higher concentrations of circulating OLFM4; and in mice, OLFM4 deficiency resulted in faster recovery and better survival after infection. Collectively, these studies provide novel insights into neutrophil-mediated pathology after CDI and highlight the pathogenic role of OLFM4 + neutrophils in regulating CDI-induced IEC damage. One Sentence Summary Utilizing single-cell transcriptomics, IEC-epithelial co-cultures, and pre-clinical models of CDI, we have identified a subset of neutrophils that are marked by OLFM4 expression as pathogenic determinants of IEC barrier damage after CDI.
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4
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Icho S, Ward JS, Tam J, Kociolek LK, Theriot CM, Melnyk RA. Intestinal bile acids provide a surmountable barrier against C. difficile TcdB-induced disease pathogenesis. Proc Natl Acad Sci U S A 2023; 120:e2301252120. [PMID: 37126691 PMCID: PMC10175849 DOI: 10.1073/pnas.2301252120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/04/2023] [Indexed: 05/03/2023] Open
Abstract
Intestinal bile acids play an essential role in the Clostridioides difficile lifecycle having been shown in vitro to modulate various aspects of pathogenesis, including spore germination, vegetative growth, and more recently the action of the primary virulence determinant, TcdB. Here, we investigated whether physiological levels of the total pool of intestinal bile acids in mice and humans protect against TcdB action. Small molecules extracted from the lumenal contents of the small intestine, cecum, colon, and feces were found to inhibit TcdB in accordance with the differential amounts of total bile acids in each compartment. Extracts from antibiotic-treated and germ-free mice, despite harboring dramatically altered bile acid profiles, unexpectedly also prevented TcdB-induced cell rounding to similar extents. We show that protection, however, is surmountable and can be overcome at higher doses of TcdB-typical to those seen during severe C. difficile infection-suggesting that the protective properties of intestinal bile acids are operant primarily under low to moderate toxin levels. Taken together, these findings demonstrate a role for intestinal bile acids in attenuating virulence, provide insights into asymptomatic carriage of toxigenic C. difficile, and inform strategies to manipulate bile acid levels for therapeutic benefit.
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Affiliation(s)
- Simoun Icho
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, ONM5G 0A4
- Department of Biochemistry, University of Toronto, Toronto, ONM5S 1A8
| | - Jennifer S. Ward
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, ONM5G 0A4
- Department of Biochemistry, University of Toronto, Toronto, ONM5S 1A8
| | - John Tam
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, ONM5G 0A4
| | - Larry K. Kociolek
- Ann & Robert H. Lurie, Children’s Hospital of Chicago, Chicago, IL60611
- Department of Pediatrics, Division of Pediatric Infectious Diseases, Northwestern University Feinberg School of Medicine, Chicago, IL60611
| | - Casey M. Theriot
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC27606
| | - Roman A. Melnyk
- Molecular Medicine Program, The Hospital for Sick Children Research Institute, Toronto, ONM5G 0A4
- Department of Biochemistry, University of Toronto, Toronto, ONM5S 1A8
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5
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Adamson H, Ajayi MO, Gilroy KE, McPherson MJ, Tomlinson DC, Jeuken LJC. Rapid Quantification of C. difficile Glutamate Dehydrogenase and Toxin B (TcdB) with a NanoBiT Split-Luciferase Assay. Anal Chem 2022; 94:8156-8163. [PMID: 35634999 PMCID: PMC9201815 DOI: 10.1021/acs.analchem.1c05206] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
C. difficile infection (CDI) is a leading healthcare-associated
infection with a high morbidity and mortality and is a financial burden.
No current standalone point-of-care test (POCT) is sufficient for
the identification of true CDI over a disease-free carriage of C. difficile, so one is urgently required to ensure timely,
appropriate treatment. Here, two types of binding proteins, Affimers
and nanobodies, targeting two C. difficile biomarkers,
glutamate dehydrogenase (GDH) and toxin B (TcdB), are combined in
NanoBiT (NanoLuc Binary Technology) split-luciferase assays. The assays
were optimized and their performance controlling parameters were examined.
The 44 fM limit of detection (LoD), 4–5 log range and 1300-fold
signal gain of the TcdB assay in buffer is the best observed for a
NanoBiT assay to date. In the stool sample matrix, the GDH and TcdB
assay sensitivity (LoD = 4.5 and 2 pM, respectively) and time to result
(32 min) are similar to a current, commercial lateral flow POCT, but
the NanoBit assay has no wash steps, detects clinically relevant TcdB
over TcdA, and is quantitative. Development of the assay into a POCT
may drive sensitivity further and offer an urgently needed ultrasensitive
TcdB test for the rapid diagnosis of true CDI. The NanoBiTBiP (NanoBiT
with Binding Proteins) system offers advantages over NanoBiT assays
with antibodies as binding elements in terms of ease of production
and assay performance. We expect this methodology and approach to
be generally applicable to other biomarkers.
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Affiliation(s)
- Hope Adamson
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Modupe O. Ajayi
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Kate E. Gilroy
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Michael J. McPherson
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Darren C. Tomlinson
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Lars J. C. Jeuken
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
- Leiden Institute of Chemistry, Leiden University, PC Box 9502, 2300 RA, Leiden, The Netherlands
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6
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Peters H, Iqbal A, Miller E, Khalid S, Rahman O. Outcomes of Continuous Enteral Vancomycin Infusion in Intensive Care Unit Patients: A Novel Treatment Modality for Severe Clostridium Difficile Colitis. Cureus 2022; 14:e22872. [PMID: 35392442 PMCID: PMC8979637 DOI: 10.7759/cureus.22872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/04/2022] [Indexed: 11/13/2022] Open
Abstract
Background and objective Severe Clostridium difficile (C. difficile) infection (CDI)-related colitis is associated with high morbidity and mortality. Current guidelines recommend oral vancomycin plus intravenous metronidazole as the first-line treatment and early total colectomy in case of medication failure. In critically ill patients at high surgical risk and with multiple comorbidities, loop ileostomy creation and enteral vancomycin infusion have been employed albeit with limited success. We hypothesized that continuous enteral vancomycin (CEV) infusion via a postpyloric feeding tube would provide a less invasive, efficacious, and safer route to treat high surgical risk patients. Methods All adult (>18 years) non-pregnant patients admitted to the ICU for severe CDI from October 2012 to October 2016 and received CEV after the failure of conventional therapy were included. Vancomycin was prepared as a 1-2-mg/ml enteral solution and run continuously through a feeding pump at 42 ml/hour via a post-pyloric feeding tube. The primary efficacy endpoint was clinical improvement defined as (a) decrease in stool output, (b) decreased vasopressor requirement, or (c) improved leukocytosis, and the secondary endpoint was treatment failure defined as the need for total colectomy or death due to severe CDI. Results Our cohort comprised 11 patients in total. The median age of the participants was 64 years, and there were more females (67%) than males (36%). Clinical improvement was seen in seven patients (63%); treatment failure documented as the need for total colectomy was observed in two patients (18%), and death attributable to CDI occurred in three patients (27%). Conclusion CEV resulted in clinical improvement in most patients with severe CDI who were at high surgical risk. Sustained intestinal vancomycin delivery may increase luminal concentration and bactericidal effect. The use of a feeding tube and pump provides an effective and less invasive route of vancomycin delivery in critically ill patients.
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7
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Heber S, Barthold L, Baier J, Papatheodorou P, Fois G, Frick M, Barth H, Fischer S. Inhibition of Clostridioides difficile Toxins TcdA and TcdB by Ambroxol. Front Pharmacol 2022; 12:809595. [PMID: 35058787 PMCID: PMC8764291 DOI: 10.3389/fphar.2021.809595] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/10/2021] [Indexed: 02/04/2023] Open
Abstract
Clostridioides (C.) difficile produces the exotoxins TcdA and TcdB, which are the predominant virulence factors causing C. difficile associated disease (CDAD). TcdA and TcdB bind to target cells and are internalized via receptor-mediated endocytosis. Translocation of the toxins’ enzyme subunits from early endosomes into the cytosol depends on acidification of endosomal vesicles, which is a prerequisite for the formation of transmembrane channels. The enzyme subunits of the toxins translocate into the cytosol via these channels where they are released after auto-proteolytic cleavage. Once in the cytosol, both toxins target small GTPases of the Rho/Ras-family and inactivate them by mono-glucosylation. This in turn interferes with actin-dependent processes and ultimately leads to the breakdown of the intestinal epithelial barrier and inflammation. So far, therapeutic approaches to treat CDAD are insufficient, since conventional antibiotic therapy does not target the bacterial protein toxins, which are the causative agents for the clinical symptoms. Thus, directly targeting the exotoxins represents a promising approach for the treatment of CDAD. Lately, it was shown that ambroxol (Ax) prevents acidification of intracellular organelles. Therefore, we investigated the effect of Ax on the cytotoxic activities of TcdA and TcdB. Ax significantly reduced toxin-induced morphological changes as well as the glucosylation of Rac1 upon intoxication with TcdA and TcdB. Most surprisingly, Ax, independent of its effects on endosomal acidification, decreased the toxins’ intracellular enzyme activity, which is mediated by a catalytic glucosyltransferase domain. Considering its undoubted safety profile, Ax might be taken into account as therapeutic option in the context of CDAD.
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Affiliation(s)
- Sebastian Heber
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany
| | - Lara Barthold
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany
| | - Jan Baier
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany
| | | | - Giorgio Fois
- Institute of General Physiology, Ulm University, Ulm, Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University, Ulm, Germany
| | - Holger Barth
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany
| | - Stephan Fischer
- Institute of Pharmacology and Toxicology, Ulm University Medical Center, Ulm, Germany
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Marquardt I, Jakob J, Scheibel J, Hofmann JD, Klawonn F, Neumann-Schaal M, Gerhard R, Bruder D, Jänsch L. Clostridioides difficile Toxin CDT Induces Cytotoxic Responses in Human Mucosal-Associated Invariant T (MAIT) Cells. Front Microbiol 2022; 12:752549. [PMID: 34992584 PMCID: PMC8727052 DOI: 10.3389/fmicb.2021.752549] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/24/2021] [Indexed: 12/31/2022] Open
Abstract
Clostridioides difficile is the major cause of antibiotic-associated colitis (CDAC) with increasing prevalence in morbidity and mortality. Severity of CDAC has been attributed to hypervirulent C. difficile strains, which in addition to toxin A and B (TcdA, TcdB) produce the binary toxin C. difficile transferase (CDT). However, the link between these toxins and host immune responses as potential drivers of immunopathology are still incompletely understood. Here, we provide first experimental evidence that C. difficile toxins efficiently activate human mucosal-associated invariant T (MAIT) cells. Among the tested toxins, CDT and more specifically, the substrate binding and pore-forming subunit CDTb provoked significant MAIT cell activation resulting in selective MAIT cell degranulation of the lytic granule components perforin and granzyme B. CDT-induced MAIT cell responses required accessory immune cells, and we suggest monocytes as a potential CDT target cell population. Within the peripheral blood mononuclear cell fraction, we found increased IL-18 levels following CDT stimulation and MAIT cell response was indeed partly dependent on this cytokine. Surprisingly, CDT-induced MAIT cell activation was found to be partially MR1-dependent, although bacterial-derived metabolite antigens were absent. However, the role of antigen presentation in this process was not analyzed here and needs to be validated in future studies. Thus, MR1-dependent induction of MAIT cell cytotoxicity might be instrumental for hypervirulent C. difficile to overcome cellular barriers and may contribute to pathophysiology of CDAC.
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Affiliation(s)
- Isabel Marquardt
- Cellular Proteomics, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Institute of Medical Microbiology and Hospital Hygiene, Infection Immunology, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.,Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Josefine Jakob
- Cellular Proteomics, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Institute of Medical Microbiology and Hospital Hygiene, Infection Immunology, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.,Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jessica Scheibel
- Cellular Proteomics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Julia Danielle Hofmann
- Braunschweig Integrated Centre of Systems Biology (BRICS), Department of Bioinformatics and Biochemistry, Technical University Braunschweig, Braunschweig, Germany
| | - Frank Klawonn
- Cellular Proteomics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Meina Neumann-Schaal
- Braunschweig Integrated Centre of Systems Biology (BRICS), Department of Bioinformatics and Biochemistry, Technical University Braunschweig, Braunschweig, Germany.,Metabolomics, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Ralf Gerhard
- Institute of Toxicology, Hannover Medical School, Hannover, Germany
| | - Dunja Bruder
- Institute of Medical Microbiology and Hospital Hygiene, Infection Immunology, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.,Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Lothar Jänsch
- Cellular Proteomics, Helmholtz Centre for Infection Research, Braunschweig, Germany
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9
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Elfassy A, Kalina WV, French R, Nguyen H, Tan C, Sebastian S, Wilcox MH, Davies K, Kutzler MA, Jansen KU, Anderson A, Pride MW. Development and clinical validation of an automated cell cytotoxicity neutralization assay for detecting Clostridioides difficile toxins in clinically relevant stools samples. Anaerobe 2021; 71:102415. [PMID: 34298152 DOI: 10.1016/j.anaerobe.2021.102415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 01/05/2023]
Abstract
OBJECTIVES To improve the diagnostic accuracy of Clostridioides difficile infection, current U.S. and E.U. guidelines recommend multistep testing that detects the presence of C. difficile and toxin in clinically relevant stool samples to confirm active disease. An accepted gold standard to detect C. difficile toxins is the cell cytotoxicity neutralization assay (CCNA). Although highly sensitive, the traditional CCNA has limitations. One such limitation is the subjective interpretation of an analyst to recognize cytopathic effects in cultured cells exposed to a fecal sample containing toxin. To overcome this limitation, an automated CCNA was developed that replaces most human pipetting steps with robotics and incorporates CellTiterGlo® for a semi-quantitative, non-subjective measure of cell viability instead of microscopy. METHODS To determine sample positivity and control for non-specific cytopathic effects, two thresholds were defined and validated by evaluating the sample with/without antitoxin antisera (sample-antitoxin/sample + antitoxin): 1) a >70% cell viability threshold was validated with samples containing anti-toxin, and 2) a >1.2-fold difference cut-off where sample results above the cut-off are considered positive. RESULTS Assay validation demonstrated excellent accuracy, precision, and sample linearity with an LOD of 126.9 pg/mL toxin-B in stool. The positivity cut-offs were clinically validated by comparing 322 diarrheal stool sample results with those run in a predicate, microscopic readout-based CCNA. The automated CCNA demonstrated 96% sensitivity and 100% specificity compared with the predicate CCNA. CONCLUSIONS Overall, the automated CCNA provides a specific, sensitive, and reproducible tool to support determination of CDI epidemiology or the efficacy of interventions such as vaccines.
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Affiliation(s)
- Arik Elfassy
- Pfizer Vaccines Research and Development, Pearl River, NY, USA; Current Affiliation: Elusys Therapeutics, Parsippany, NJ, USA
| | - Warren V Kalina
- Pfizer Vaccines Research and Development, Pearl River, NY, USA
| | - Roger French
- Pfizer Vaccines Research and Development, Pearl River, NY, USA
| | - Ha Nguyen
- Pfizer Vaccines Research and Development, Pearl River, NY, USA
| | - Charles Tan
- Pfizer Vaccines Research and Development, Pearl River, NY, USA
| | - Shite Sebastian
- Pfizer Vaccines Research and Development, Pearl River, NY, USA; Current Affiliation: Affinivax, Lexington, MA, USA
| | - Mark H Wilcox
- Leeds Teaching Hospitals NHS Trust and University of Leeds, Leeds, United Kingdom
| | - Kerrie Davies
- Leeds Teaching Hospitals NHS Trust and University of Leeds, Leeds, United Kingdom
| | | | | | | | - Michael W Pride
- Pfizer Vaccines Research and Development, Pearl River, NY, USA.
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10
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Alonso CD, Kelly CP, Garey KW, Gonzales-Luna AJ, Williams D, Daugherty K, Cuddemi C, Villafuerte-Gálvez J, White NC, Chen X, Xu H, Sprague R, Barrett C, Miller M, Foussadier A, Lantz A, Banz A, Pollock NR. Ultrasensitive and quantitative toxin measurement correlates with baseline severity, severe outcomes, and recurrence among hospitalized patients with Clostridioides difficile infection. Clin Infect Dis 2021; 74:2142-2149. [PMID: 34537841 DOI: 10.1093/cid/ciab826] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Stool toxin concentrations may impact Clostridioides difficile infection (CDI) severity and outcomes. We correlated fecal C. difficile toxin concentrations, measured by an ultrasensitive and quantitative assay, with CDI baseline severity, attributable outcomes, and recurrence. METHODS We enrolled 615 hospitalized adults (≥ 18y) with CDI (acute diarrhea, positive stool NAAT, and decision to treat). Baseline stool toxin A and B concentrations were measured by Single Molecule Array. Subjects were classified by baseline CDI severity (four scoring methods) and outcomes within 40 days (death, ICU stay, colectomy, and recurrence). RESULTS Among 615 patients (median 68.0 years), in all scoring systems, subjects with severe baseline disease had higher stool toxin A+B concentrations than those without (P<0.01). Nineteen subjects (3.1%) had a severe outcome primarily-attributed to CDI (group 1). This group had higher median toxin A+B [14,303 pg/mL (IQR 416.0, 141,967)] than subjects in whom CDI only contributed to the outcome [group 2, 163.2 pg/mL(0.0, 8423.3)], subjects with severe outcome unrelated to CDI [group 3, 158.6 pg/mL (0.0, 1795.2)], or no severe outcome [group 4, 209.5 pg/mL (0.0, 8566.3)](P=0.003). Group 1 was more likely to have detectable toxin (94.7%) than groups 2-4 (60.5-66.1%)(P=0.02). Individuals with recurrence had higher toxin A+B [2266.8 pg/mL(188.8, 29411)] than those without [154.0 pg/mL(0.0, 5864.3)](P<0.001) and higher rates of detectable toxin (85.7% versus 64.0%, P=0.004). CONCLUSIONS In CDI patients, ultrasensitive stool toxin detection and concentration correlated with severe baseline disease, severe CDI-attributable outcomes, and recurrence, confirming the contribution of toxin quantity to disease presentation and clinical course.
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Affiliation(s)
- Carolyn D Alonso
- Division of Infectious Disease, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA
| | - Ciarán P Kelly
- Harvard Medical School, Boston, MA, USA.,Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Kevin W Garey
- Department of Pharmacy Practice and Translational Research, University of Houston College, of Pharmacy, Houston, TX, USA
| | - Anne J Gonzales-Luna
- Department of Pharmacy Practice and Translational Research, University of Houston College, of Pharmacy, Houston, TX, USA
| | - David Williams
- Institutional Centers for Clinical and Translational Research, Boston Children's Hospital, Boston, MA, USA
| | - Kaitlyn Daugherty
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Christine Cuddemi
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Javier Villafuerte-Gálvez
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Nicole C White
- Division of Infectious Disease, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Xinhua Chen
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Hua Xu
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Rebecca Sprague
- Division of Infectious Disease, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Caitlin Barrett
- Division of Infectious Disease, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | | | | | | | | | - Nira R Pollock
- Division of Infectious Disease, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Department of Laboratory Medicine, Boston Children's Hospital, Boston, Massachusetts, USA
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11
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Hassanain WA, Spoors J, Johnson CL, Faulds K, Keegan N, Graham D. Rapid ultra-sensitive diagnosis of clostridium difficile infection using a SERS-based lateral flow assay. Analyst 2021; 146:4495-4505. [PMID: 34184680 DOI: 10.1039/d1an00726b] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Clostridium difficile (C. diff) infection is one of the most contagious diseases associated with high morbidity and mortality rates in hospitalised patients. Accurate diagnosis can slow its spread by determining the most effective treatment. Herein, we report a novel testing platform as a proof-of-concept for the selective, sensitive, rapid and cost-effective diagnosis of C. diff infection (CDI) based on a duplex measurement. This was achieved by detecting two specific biomarkers, surface layer protein A (SlpA) and toxin B (ToxB), using a surface enhanced Raman scattering-based lateral flow assay (SERS-based LFA). The simultaneous duplex detection of SlpA with ToxB has not been described for the clinical diagnosis of CDI previously. The SlpA biomarker "AKDGSTKEDQLVDALA" was first reported by our group in 2018 as a species-specific identification tool. The second biomarker, ToxB, is the essential virulence biomarker of C. diff pathogenic strains and is required to confirm true infection pathogenicity. The proposed SERS-based LFA platform enabled rapid duplex detection of SlpA and ToxB on separate test lines using a duplex LF test strip within 20 minutes. The use of a handheld Raman spectrometer to scan test lines allowed for the highly sensitive quantitative detection of both biomarkers with a lowest observable concentration of 0.01 pg μL-1. The use of a handheld device in this SERS-based LFA instead of benchtop machine paves the way for rapid, selective, sensitive and cheap clinical evaluation of CDI at the point of care (POC) with minimal sample backlog.
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Affiliation(s)
- Waleed A Hassanain
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
| | - Julia Spoors
- Diagnostic and Therapeutic Technologies, Translational and Clinical Research Institute, Newcastle University, Newcastle-Upon-Tyne, NE2 4HH, UK.
| | - Christopher L Johnson
- Diagnostic and Therapeutic Technologies, Translational and Clinical Research Institute, Newcastle University, Newcastle-Upon-Tyne, NE2 4HH, UK.
| | - Karen Faulds
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
| | - Neil Keegan
- Diagnostic and Therapeutic Technologies, Translational and Clinical Research Institute, Newcastle University, Newcastle-Upon-Tyne, NE2 4HH, UK.
| | - Duncan Graham
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
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12
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Xu X, Bian Q, Luo Y, Song X, Lin S, Chen H, Liang Q, Wang M, Ye G, Zhu B, Chen L, Tang YW, Wang X, Jin D. Comparative Whole Genome Sequence Analysis and Biological Features of Clostridioides difficile Sequence Type 2 ‡. Front Microbiol 2021; 12:651520. [PMID: 34290677 PMCID: PMC8287029 DOI: 10.3389/fmicb.2021.651520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 05/31/2021] [Indexed: 01/05/2023] Open
Abstract
Clostridioides difficile sequence type 2 (ST2) has been increasingly recognized as one of the major genotypes in China, while the genomic characteristics and biological phenotypes of Chinese ST2 strains remain to be determined. We used whole-genome sequencing and phylogenetic analysis to investigate the genomic features of 182 ST2 strains, isolated between 2011 and 2017. PCR ribotyping (RT) was performed, and antibiotic resistance, toxin concentration, and sporulation capacity were measured. The core genome Maximum-likelihood phylogenetic analysis showed that ST2 strains were distinctly segregated into two genetically diverse lineages [L1 (67.0% from Northern America) and L2], while L2 further divided into two sub-lineages, SL2a and SL2b (73.5% from China). The 36 virulence-related genes were widely distributed in ST2 genomes, but in which only 11 antibiotic resistance-associated genes were dispersedly found. Among the 25 SL2b sequenced isolates, RT014 (40.0%, n = 10) and RT020 (28.0%, n = 7) were two main genotypes with no significant difference on antibiotic resistance (χ2 = 0.024-2.667, P > 0.05). A non-synonymous amino acid substitution was found in tcdB (Y1975D) which was specific to SL2b. Although there was no significant difference in sporulation capacity between the two lineages, the average toxin B concentration (5.11 ± 3.20 ng/μL) in SL2b was significantly lower in comparison to those in L1 (10.49 ± 15.82 ng/μL) and SL2a (13.92 ± 2.39 ng/μL) (χ2 = 12.30, P < 0.05). This study described the genomic characteristics of C. difficile ST2, with many virulence loci and few antibiotic resistance elements. The Chinese ST2 strains with the mutation in codon 1975 of the tcdB gene clustering in SL2b circulating in China express low toxin B, which may be associated with mild or moderate C. difficile infection.
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Affiliation(s)
- Xingxing Xu
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
| | - Qiao Bian
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Yun Luo
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Xiaojun Song
- Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Shan Lin
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China
| | - Huan Chen
- Key Laboratory of Microorganism Technology and Bioinformatics Research of Zhejiang Province, Hangzhou, China.,NMPA Key Laboratory for Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, China
| | - Qian Liang
- Key Laboratory of Microorganism Technology and Bioinformatics Research of Zhejiang Province, Hangzhou, China.,NMPA Key Laboratory for Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, China
| | - Meixia Wang
- Key Laboratory of Microorganism Technology and Bioinformatics Research of Zhejiang Province, Hangzhou, China.,NMPA Key Laboratory for Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, China
| | - Guangyong Ye
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Bo Zhu
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Liang Chen
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, Untied States.,Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, NJ, Untied States
| | - Yi-Wei Tang
- Cepheid, Danaher Diagnostic Platform, Shanghai, China
| | - Xianjun Wang
- Department of Clinical Laboratory, Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Dazhi Jin
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, China.,Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
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13
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Intestinal Inflammation and Altered Gut Microbiota Associated with Inflammatory Bowel Disease Render Mice Susceptible to Clostridioides difficile Colonization and Infection. mBio 2021; 12:e0273320. [PMID: 34126769 PMCID: PMC8262858 DOI: 10.1128/mbio.02733-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Clostridioides difficile is a noteworthy pathogen in patients with inflammatory bowel disease (IBD). Patients with IBD who develop concurrent C. difficile infection (CDI) experience increased morbidity and mortality. IBD is associated with intestinal inflammation and alterations of the gut microbiota, both of which can diminish colonization resistance to C. difficile. Here, we describe the development of a mouse model to explore the role that IBD-induced changes of the gut microbiome play in susceptibility to C. difficile. Helicobacter hepaticus, a normal member of the mouse gut microbiota, triggers pathological inflammation in the distal intestine akin to human IBD in mice that lack intact interleukin 10 (IL-10) signaling. We demonstrate that mice with H. hepaticus-induced IBD were susceptible to C. difficile colonization in the absence of other perturbations, such as antibiotic treatment. Concomitant IBD and CDI were associated with significantly worse disease than observed in animals with colitis alone. Development of IBD resulted in a distinct intestinal microbiota community compared to that of non-IBD controls. Inflammation played a critical role in the susceptibility of animals with IBD to C. difficile colonization, as mice colonized with an isogenic mutant of H. hepaticus that triggers an attenuated intestinal inflammation maintained full colonization resistance. These studies with a novel mouse model of IBD and CDI emphasize the importance of host responses and alterations of the gut microbiota in susceptibility to C. difficile colonization and infection in the setting of IBD.
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14
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Xu X, Luo Y, Chen H, Song X, Bian Q, Wang X, Liang Q, Zhao J, Li C, Song G, Yang J, Sun L, Jiang J, Wang H, Zhu B, Ye G, Chen L, Tang YW, Jin D. Genomic evolution and virulence association of Clostridioides difficile sequence type 37 (ribotype 017) in China. Emerg Microbes Infect 2021; 10:1331-1345. [PMID: 34125660 PMCID: PMC8253194 DOI: 10.1080/22221751.2021.1943538] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Clostridioides difficile sequence type (ST) 37 (ribotype 017) is one of the most prevalent genotypes circulating in China. However, its genomic evolution and virulence determinants were rarely explored. Whole-genome sequencing, phylogeographic and phylogenetic analyses were conducted for C. difficile ST37 isolates. The 325 ST37 genomes from six continents, including North America (n = 66), South America (n = 4), Oceania (n = 7), Africa (n = 9), Europe (n = 138) and Asia (n = 101), were clustered into six major lineages, with region-dependent distributions, harbouring an array of antibiotic-resistance genes. The ST37 strains from China were divided into four distinct sublineages, showing five importation times and international sources. Isolates associated with severe infections exhibited significantly higher toxin productions, tcdB mRNA levels, and sporulation capacities (P < 0.001). Kyoto Encyclopedia of Genes and Genomes analysis showed 10 metabolic pathways were significantly enriched in the mutations among isolates associated with severe CDI (P < 0.05). Gene mutations in glycometabolism, amino acid metabolism and biosynthesis virtually causing instability in protein activity were correlated positively to the transcription of tcdR and negatively to the expression of toxin repressor genes, ccpA and codY. In summary, our study firstly presented genomic insights into genetic characteristics and virulence association of C. difficile ST37 in China. Gene mutations in certain important metabolic pathways are associated with severe symptoms and correlated with higher virulence in C. difficile ST37 isolates.
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Affiliation(s)
- Xingxing Xu
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Yuo Luo
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
| | - Huan Chen
- Key Laboratory of Microorganism technology and bioinformatics research of Zhejiang Province, Hangzhou, People's Republic of China.,NMPA Key Laboratory For Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, People's Republic of China
| | - Xiaojun Song
- Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Qiao Bian
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, People's Republic of China
| | - Xianjun Wang
- Department of Laboratory Medicine, Hangzhou First People's Hospital, Hangzhou, People's Republic of China
| | - Qian Liang
- Key Laboratory of Microorganism technology and bioinformatics research of Zhejiang Province, Hangzhou, People's Republic of China.,NMPA Key Laboratory For Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, People's Republic of China
| | - Jianhong Zhao
- Department of Clinical Microbiology, Second Hospital of Hebei Medical University, Hebei Provincial Center for Clinical Laboratories, Shijiazhuang, People's Republic of China
| | - Chunhui Li
- Infection Control Center, Xiangya Hospital of Central South University, Changsha, People's Republic of China
| | - Guangzhong Song
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Jun Yang
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, People's Republic of China
| | - Lingli Sun
- Key Laboratory of Microorganism technology and bioinformatics research of Zhejiang Province, Hangzhou, People's Republic of China.,NMPA Key Laboratory For Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, People's Republic of China
| | - Jianmin Jiang
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, People's Republic of China
| | - Huanying Wang
- Key Laboratory of Microorganism technology and bioinformatics research of Zhejiang Province, Hangzhou, People's Republic of China.,NMPA Key Laboratory For Testing and Risk Warning of Pharmaceutical Microbiology, Hangzhou, People's Republic of China
| | - Bo Zhu
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Guangyong Ye
- Department of Clinical Laboratory, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Liang Chen
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, USA.,Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, NJ, USA
| | - Yi-Wei Tang
- Cepheid, Danaher Diagnostic Platform, Shanghai, People's Republic of China
| | - Dazhi Jin
- School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, People's Republic of China.,Centre of Laboratory Medicine, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, People's Republic of China
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15
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Mizusawa M, Carroll KC. Advances and required improvements in methods to diagnosing Clostridioides difficile infections in the healthcare setting. Expert Rev Mol Diagn 2021; 21:311-321. [PMID: 33682564 DOI: 10.1080/14737159.2021.1900737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Clostrididioides difficile is associated with adverse clinical outcomes and increased morbidity, mortality, length of hospital stay, and health-care costs.Areas Covered: We searched relevant papers in PubMed for the last 10 years. In major papers, we scanned the bibliographies to ensure that important articles were included. This review addresses the evolving epidemiology of Clostridioides difficile infection (CDI) and discusses novel methods/approaches for improving the diagnosis of this important disease. EXPERT OPINION No single diagnostic test to date has demonstrated optimum sensitivity and specificity for detection of CDI. Many institutions have developed multi-step algorithms consistent with guidelines established by various professional societies. Some institutions have successfully tried to improve the pretest probability of molecular assays by implementing appropriate sample rejection criteria and establishing best practice alerts at the time of electronic order entry. Others have established PCR cycle threshold cutoffs to attempt to differentiate symptomatic patients from asymptomatic carriers or to make predictions about severity of disease with variable success. As research advances our understanding of C. difficile pathogenesis and pathophysiology, more information on CDI specific biomarkers is emerging. Finally, assessments of the microbiome and metabolome may expand the diagnostic armamentarium with advances in mass spectrometry and sequencing technologies.
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Affiliation(s)
- Masako Mizusawa
- Section of Infectious Diseases, Department of Internal Medicine, University of Missouri, Kansas City, Missouri, Kansas City, MO, USA
| | - Karen C Carroll
- Director Division of Medical Microbiology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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16
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Bernardo L, Corallo L, Caterini J, Su J, Gisonni-Lex L, Gajewska B. Application of xCELLigence real-time cell analysis to the microplate assay for pertussis toxin induced clustering in CHO cells. PLoS One 2021; 16:e0248491. [PMID: 33720984 PMCID: PMC7959359 DOI: 10.1371/journal.pone.0248491] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/27/2021] [Indexed: 02/06/2023] Open
Abstract
The microplate assay with Chinese Hamster Ovary (CHO) cells is currently used as a safety test to monitor the residual pertussis toxin (PT) amount in acellular pertussis antigens prior to vaccine formulation. The assay is based on the findings that the exposure of CHO cells to PT results in a concentration-dependent clustering response which can be used to estimate the amount of PT in a sample preparation. A major challenge with the current CHO cell assay methodology is that scoring of PT-induced clustering is dependent on subjective operator visual assessment using light microscopy. In this work, we have explored the feasibility of replacing the microscopy readout for the CHO cell assay with the xCELLigence Real-Time Cell Analysis system (ACEA BioSciences, a part of Agilent). The xCELLigence equipment is designed to monitor cell adhesion and growth. The electrical impedance generated from cell attachment and proliferation is quantified via gold electrodes at the bottom of the cell culture plate wells, which is then translated into a unitless readout called cell index. Results showed significant decrease in the cell index readouts of CHO cells exposed to PT compared to the cell index of unexposed CHO cells. Similar endpoint concentrations were obtained when the PT reference standard was titrated with either xCELLigence or microscopy. Testing genetically detoxified pertussis samples unspiked or spiked with PT further supported the sensitivity and reproducibility of the xCELLigence assay in comparison with the conventional microscopy assay. In conclusion, the xCELLigence RTCA system offers an alternative automated and higher throughput method for evaluating PT-induced clustering in CHO cells.
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Affiliation(s)
- Lidice Bernardo
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
- * E-mail:
| | - Lucas Corallo
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
| | - Judy Caterini
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
| | - Jin Su
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
| | - Lucy Gisonni-Lex
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
| | - Beata Gajewska
- Department of Analytical Sciences, Sanofi Pasteur, Toronto, ON, Canada
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17
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Farrow MA, Chumber NM, Bloch SC, King M, Moton-Melancon K, Shupe J, Washington MK, Spiller BW, Lacy DB. Small Molecule Inhibitor Screen Reveals Calcium Channel Signaling as a Mechanistic Mediator of Clostridium difficile TcdB-Induced Necrosis. ACS Chem Biol 2020; 15:1212-1221. [PMID: 31909964 DOI: 10.1021/acschembio.9b00906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Clostridioides difficile is the leading cause of nosocomial diarrhea in the United States. The primary virulence factors are two homologous glucosyltransferase toxins, TcdA and TcdB, that inactivate host Rho-family GTPases. The glucosyltransferase activity has been linked to a "cytopathic" disruption of the actin cytoskeleton and contributes to the disruption of tight junctions and the production of pro-inflammatory cytokines. TcdB is also a potent cytotoxin that causes epithelium necrotic damage through an NADPH oxidase (NOX)-dependent mechanism. We conducted a small molecule screen to identify compounds that confer protection against TcdB-induced necrosis. We identified an enrichment of "hit compounds" with a dihydropyridine (DHP) core which led to the discovery of a key early stage calcium signal that serves as a mechanistic link between TcdB-induced NOX activation and reactive oxygen species (ROS) production. Disruption of TcdB-induced calcium signaling (with both DHP and non-DHP molecules) is sufficient to ablate ROS production and prevent subsequent necrosis in cells and in a mouse model of intoxication.
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Affiliation(s)
- Melissa A. Farrow
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - Nicole M. Chumber
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - Sarah C. Bloch
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - McKenzie King
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - Kaycei Moton-Melancon
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - John Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - Mary K. Washington
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
| | - Benjamin W. Spiller
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, A4116A Medical Center North, 1161 21st Avenue South, Nashville, Tennessee 37232-2363, United States
- The Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee 37212, United States
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18
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Gai X, Liu C, Wang G, Qin Y, Fan C, Liu J, Shi Y. A novel method for evaluating the dynamic biocompatibility of degradable biomaterials based on real-time cell analysis. Regen Biomater 2020; 7:321-329. [PMID: 32523733 PMCID: PMC7266667 DOI: 10.1093/rb/rbaa017] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/10/2020] [Accepted: 03/29/2020] [Indexed: 12/18/2022] Open
Abstract
Degradable biomaterials have emerged as a promising type of medical materials because of their unique advantages of biocompatibility, biodegradability and biosafety. Owing to their bioabsorbable and biocompatible properties, magnesium-based biomaterials are considered as ideal degradable medical implants. However, the rapid corrosion of magnesium-based materials not only limits their clinical application but also necessitates a more specific biological evaluation system and biosafety standard. In this study, extracts of pure Mg and its calcium alloy were prepared using different media based on ISO 10993:12; the Mg2+ concentration and osmolality of each extract were measured. The biocompatibility was investigated using the MTT assay and xCELLigence real-time cell analysis (RTCA). Cytotoxicity tests were conducted with L929, MG-63 and human umbilical vein endothelial cell lines. The results of the RTCA highly matched with those of the MTT assay and revealed the different dynamic modes of the cytotoxic process, which are related to the differences in the tested cell lines, Mg-based materials and dilution rates of extracts. This study provides an insight on the biocompatibility of biodegradable materials from the perspective of cytotoxic dynamics and suggests the applicability of RTCA for the cytotoxic evaluation of degradable biomaterials.
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Affiliation(s)
- Xiaoxiao Gai
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Chenghu Liu
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Guowei Wang
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Yang Qin
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Chunguang Fan
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Jia Liu
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
| | - Yanping Shi
- Department of Biological Evaluation, Shandong Quality Inspection Center for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Shandong Key Laboratory of Biological Evaluation for Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China.,Department of Biological Evaluation, NMPA Key Laboratory for Safety Evaluation of Biomaterials and Medical Devices, NO.15166 Century Avenue, H-T Industrial Development Zone, Jinan 250101, China
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Prospective Evaluation of the mariPOC Test for Detection of Clostridioides difficile Glutamate Dehydrogenase and Toxins A/B. J Clin Microbiol 2020; 58:JCM.01872-19. [PMID: 31941691 DOI: 10.1128/jcm.01872-19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 12/18/2019] [Indexed: 11/20/2022] Open
Abstract
The objective of this study was to evaluate a novel automated random-access test, mariPOC CDI (ArcDia Ltd., Finland), for the detection of Clostridioides difficile glutamate dehydrogenase (GDH) and toxins A and B directly from fecal specimens. The mariPOC test was compared with both the GenomEra C. difficile PCR assay (Abacus Diagnostica Oy, Finland) and the TechLab C. diff Quik Chek Complete (Alere Inc.; now Abbot) membrane enzyme immunoassay (MEIA). Culture and the Xpert C. difficile assay (Cepheid Inc., USA) were used to resolve discrepant results. In total, 337 specimens were tested with the mariPOC CDI test and GenomEra PCR. Of these specimens, 157 were also tested with the TechLab MEIA. The sensitivity of the mariPOC test for GDH was slightly lower (95.2%) than that obtained with the TechLab assay (100.0%), but no toxin-positive cases were missed. The sensitivity of the mariPOC test for the detection of toxigenic C. difficile by analyzing toxin expression was better (81.6%) than that of the TechLab assay (71.1%). The analytical specificities for the mariPOC and the TechLab tests were 98.3% and 100.0% for GDH and 100.0% and 99.2% for toxin A/B, respectively. The analytical specificity of the GenomEra method was 100.0%. The mariPOC and TechLab GDH tests and GenomEra PCR had high negative predictive values of 99.3%, 98.3%, and 99.7%, respectively, in excluding infection with toxigenic C. difficile The mariPOC toxin A/B test and GenomEra PCR had an identical analytical positive predictive value of 100%, providing highly reliable information about toxin expression and the presence of toxin genes, respectively.
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20
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Zhao L, Luo Y, Bian Q, Wang L, Ye J, Song X, Jiang J, Tang YW, Wang X, Jin D. High-Level Resistance of Toxigenic Clostridioides difficile Genotype to Macrolide-Lincosamide- Streptogramin B in Community Acquired Patients in Eastern China. Infect Drug Resist 2020; 13:171-181. [PMID: 32021331 PMCID: PMC6974413 DOI: 10.2147/idr.s238916] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 12/26/2019] [Indexed: 01/02/2023] Open
Abstract
Background Clostridioides difficile resistant to macrolide-lincosamide-streptogramin B (MLSB) has not been reported in China. Methods In a cross-sectional study in two tertiary hospitals, C. difficile isolates from stool specimens from community-onset, hospital-associated diarrheal patients were analyzed for toxin genes, genotype, and antibiotic resistance, and the patients’ clinical charts were reviewed. Results A total of 190 (15.2%) isolates (102 A+B+ and 88 A−B+) from 1250 community acquired (CA) patients were recovered and all were susceptible to vancomycin and metronidazole. High-level resistance (minimum inhibitory concentration > 128 mg/L) to erythromycin and clindamycin was recorded in 77.9% and 88.4% of the tested isolates, respectively. Furthermore, 89.3% (159/178) of the isolates resistant to MLSB carried the erythromycin resistance methylase gene (ermB). The statistically significant factors associated with C. difficile infection (CDI) induced by A−B+ isolates with MLSB resistance included a severity score of >2 (odds ratio [95% confidence interval], 7.43 [2.31–23.87]) and platelet count (cells × 109 cells/L) < 100 [5.19 (1.58–17.04)]. The proportion of A−B+ increased with enhanced CDI severity (x2 = 21.62, P < 0.001), which was significantly higher than that of ermB-positive A+B+ in severity score of 4 (x2 = 8.61, P = 0.003). The average severity score of ermB-positive isolates was significantly higher than that of ermB-negative isolates in A−B+ (Z = −2.41, P = 0.016). Conclusion The ermB-positive A−B+C. difficile with MLSB resistance is described for the first time as a potential epidemic clone inducing severe CDI in CA diarrheal patients in Eastern China.
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Affiliation(s)
- Longyou Zhao
- Lishui Second People's Hospital, Lishui, Zhejiang, People's Republic of China
| | - Yun Luo
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Qiao Bian
- School of Medicine, Ningbo University, Ningbo, Zhejiang, People's Republic of China.,Centre of Laboratory Medicine, Zhejiang Provincial People Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang, People's Republic of China
| | - Liqian Wang
- Department of Laboratory Medicine, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People's Republic of China
| | - Julian Ye
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, People's Republic of China
| | - Xiaojun Song
- Centre of Laboratory Medicine, Zhejiang Provincial People Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang, People's Republic of China.,School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, People's Republic of China
| | - Jianmin Jiang
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, People's Republic of China.,Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, Zhejiang, People's Republic of China
| | - Yi-Wei Tang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, USA.,Cepheid, Danaher Diagnostic Platform, Shanghai, People's Republic of China
| | - Xianjun Wang
- Department of Laboratory Medicine, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People's Republic of China
| | - Dazhi Jin
- Centre of Laboratory Medicine, Zhejiang Provincial People Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang, People's Republic of China.,School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, People's Republic of China
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21
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Cole LE, Li L, Jetley U, Zhang J, Pacheco K, Ma F, Zhang J, Mundle S, Yan Y, Barone L, Rogers C, Beltraminelli N, Quemeneur L, Kleanthous H, Anderson SF, Anosova NG. Deciphering the domain specificity of C. difficile toxin neutralizing antibodies. Vaccine 2019; 37:3892-3901. [PMID: 31122858 DOI: 10.1016/j.vaccine.2019.05.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 04/10/2019] [Accepted: 05/13/2019] [Indexed: 12/21/2022]
Abstract
Clostridium difficile infection (CDI) is the principal cause of nosocomial diarrhea and pseudomembranous colitis associated with antibiotic therapy. The pathological effects of CDI are primarily attributed to toxins A (TcdA) and B (TcdB). Adequate toxin-specific antibody responses are associated with asymptomatic carriage, whereas insufficient humoral responses are associated with recurrent CDI. While the data supporting the importance of anti-toxin antibodies are substantial, clarity about the toxin domain specificity of these antibodies is more limited. To investigate this matter, combinations of human mAbs targeting multiple domains of TcdB were assessed using toxin neutralization assays. These data revealed that a combination of mAbs specific to all major toxin domains had improved neutralizing potency when compared to equivalent concentrations of a single mAb or a combination of mAbs against one or two domains. The function and toxin domain binding specificity of serum antibodies elicited by immunization of hamsters with a toxoid vaccine candidate was also assessed. Immunization with a toxoid vaccine candidate provoked toxin neutralizing antibodies specific to multiple domains of both TcdA and TcdB. When assessed in a toxin neutralization assay, polyclonal sera displayed greater activity against elevated concentrations of toxins than equivalent concentrations of individual mAbs. These data suggest a potential benefit of any antibody based therapeutic or prophylactic treatment that targets multiple toxin domains.
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Affiliation(s)
- Leah E Cole
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Lu Li
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Utsav Jetley
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA; Momenta Pharmaceuticals, INC., Research, 675 W Kendall St, Cambridge, MA 02142, USA
| | - Jinrong Zhang
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Kristl Pacheco
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Fuqin Ma
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Jianxin Zhang
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Sophia Mundle
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Yanhua Yan
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Lucianna Barone
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA; Harvard Vanguard Medical Associates, 230 Worcester Street, Wellesley, MA 02481, USA
| | - Christopher Rogers
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA; Maine Medical Center, Department of Pediatrics, 22 Bramhall Street, Portland, ME 04102, USA
| | - Nicola Beltraminelli
- BliNK Biomedical SAS, R&D, Gerland Plaza Techsud, 70, rue Saint Jean de Dieu, 69007 Lyon, France
| | - Laurence Quemeneur
- Sanofi Pasteur, Research Europe, 1541, Avenue Marcel Mérieux, 68280 Marcy l'Etoile, France
| | - Harry Kleanthous
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA
| | - Stephen F Anderson
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA; Anokion US, Inc., Development and Analytics, 50 Hampshire Street, Cambridge, MA 02139, USA
| | - Natalie G Anosova
- Sanofi Pasteur, Research North America, 38 Sidney Street, Cambridge, MA 02139, USA.
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22
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Yan G, Du Q, Wei X, Miozzi J, Kang C, Wang J, Han X, Pan J, Xie H, Chen J, Zhang W. Application of Real-Time Cell Electronic Analysis System in Modern Pharmaceutical Evaluation and Analysis. Molecules 2018; 23:E3280. [PMID: 30544947 PMCID: PMC6321149 DOI: 10.3390/molecules23123280] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 12/11/2022] Open
Abstract
Objective: We summarized the progress of the xCELLigence real-time cell analysis (RTCA) technology application in recent years for the sake of enriching and developing the application of RTCA in the field of Chinese medicine. Background: The RTCA system is an established electronic cellular biosensor. This system uses micro-electronic biosensor technology that is confirmed for real-time, label-free, dynamic and non-offensive monitoring of cell viability, migration, growth, spreading, and proliferation. Methods: We summarized the relevant experiments and literature of RTCA technology from the principles, characteristics, applications, especially from the latest application progress. Results and conclusion: RTCA is attracting more and more attention. Now it plays an important role in drug screening, toxicology, Chinese herbal medicine and so on. It has wide application prospects in the area of modern pharmaceutical evaluation and analysis.
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Affiliation(s)
- Guojun Yan
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Qian Du
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou 221004, China.
| | - Xuchao Wei
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Jackelyn Miozzi
- Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH 43210, USA.
| | - Chen Kang
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
| | - Jinnv Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Xinxin Han
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Jinhuo Pan
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Hui Xie
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Jun Chen
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Weihua Zhang
- Beijing Body Revival Medical Technology Co., Ltd., Beijing 100088, China.
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23
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Ultrasensitive Detection of Clostridioides difficile Toxins A and B by Use of Automated Single-Molecule Counting Technology. J Clin Microbiol 2018; 56:JCM.00908-18. [PMID: 30158195 DOI: 10.1128/jcm.00908-18] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/27/2018] [Indexed: 12/12/2022] Open
Abstract
Current tests for the detection of Clostridioides (formerly Clostridium) difficile free toxins in feces lack sensitivity, while nucleic acid amplification tests lack clinical specificity. We have evaluated the Singulex Clarity C. diff toxins A/B assay (currently in development), an automated and rapid ultrasensitive immunoassay powered by single-molecule counting technology, for detection of C. difficile toxin A (TcdA) and toxin B (TcdB) in stool. The analytical sensitivity, analytical specificity, repeatability, and stability of the assay were determined. In a clinical evaluation, frozen stool samples from 311 patients with suspected C. difficile infection were tested with the Clarity C. diff toxins A/B assay, using an established cutoff value. Samples were tested with the Xpert C. difficile/Epi assay, and PCR-positive samples were tested with an enzyme immunoassay (EIA) (C. Diff Quik Chek Complete). EIA-negative samples were further tested with a cell cytotoxicity neutralization assay. The limits of detection for TcdA and TcdB were 0.8 and 0.3 pg/ml in buffer and 2.0 and 0.7 pg/ml in stool, respectively. The assay demonstrated reactivity to common C. difficile strains, did not show cross-reactivity to common gastrointestinal pathogens, was robust against common interferents, allowed detection in fresh and frozen stool samples and in samples after three freeze-thaw cycles, and provided results with high reproducibility. Compared to multistep PCR and toxin-testing procedures, the Singulex Clarity C. diff toxins A/B assay yielded 97.7% sensitivity and 100% specificity. The Singulex Clarity C. diff toxins A/B assay is ultrasensitive and highly specific and may offer a standalone solution for rapid detection and quantitation of free toxins in stool.
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24
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A low-cost paper-based synthetic biology platform for analyzing gut microbiota and host biomarkers. Nat Commun 2018; 9:3347. [PMID: 30131493 PMCID: PMC6104080 DOI: 10.1038/s41467-018-05864-4] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 07/20/2018] [Indexed: 12/13/2022] Open
Abstract
There is a need for large-scale, longitudinal studies to determine the mechanisms by which the gut microbiome and its interactions with the host affect human health and disease. Current methods for profiling the microbiome typically utilize next-generation sequencing applications that are expensive, slow, and complex. Here, we present a synthetic biology platform for affordable, on-demand, and simple analysis of microbiome samples using RNA toehold switch sensors in paper-based, cell-free reactions. We demonstrate species-specific detection of mRNAs from 10 different bacteria that affect human health and four clinically relevant host biomarkers. We develop a method to quantify mRNA using our toehold sensors and validate our platform on clinical stool samples by comparison to RT-qPCR. We further highlight the potential clinical utility of the platform by showing that it can be used to rapidly and inexpensively detect toxin mRNA in the diagnosis of Clostridium difficile infections. Currently, gut microbiome profiling largely relies on next-generation sequencing, which is slow and expensive. Here, the authors develop a low-cost, paper-based synthetic biology platform that allows species-specific quantification of bacterial mRNAs and clinically relevant host biomarkers.
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25
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Xu X, Luo Y, Song X, Ying J, Ye J, Lu Y, Cai J, Ma J, Wang X, Yu W, Wang Y, Jin D. Evaluation of an UltraFast LabChip V280 assay for detection of toxigenic Clostridium difficile. Diagn Microbiol Infect Dis 2018; 92:279-283. [PMID: 30029809 DOI: 10.1016/j.diagmicrobio.2018.06.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/21/2018] [Accepted: 06/23/2018] [Indexed: 01/03/2023]
Abstract
In this study, we compared the performance of an UltraFast LabChip (UL) V280 system for Clostridium difficile detection in stool with that of Xpert C. difficile/Epi and VIDAS CDAB. Among 176 stool specimens, UL V280 detected toxigenic C. difficile in 22 (22/176, 12.5%) with a sensitivity, specificity, positive predictive value, negative predictive value (NPV) of 100.0%, 99.4%, 99.5% and 100.0%, respectively, which were higher than 95.2%, 97.4%, 83.3%, and 99.3% of Xpert C. difficile/Epi (P > 0.05). Notably, the sensitivity and NPV of ULV280 were significantly higher than those of VIDAS CDAB 52.4% (P < 0.001, odds ratio [OR] = 20.0, 95% confidence interval [CI] = 2.26-176.81) and 93.8% (P = 0.002, OR = 10.27, 95% CI = 1.30-81.17). UL V280 turnaround time (35 min) and cost (6.24 Dollars [$]) per specimen were less than those for Xpert C. difficile/Epi (47 min, 59.26 $) and VIDAS CDAB (65 min, 11.70 $). UL V280 possessed an analytical sensitivity limit of 2500 CFU/ml, 95% [CI] = (Ct: 30.76-34.90), and no cross-reactions with other pathogens were found. The study demonstrates that UL V280 based on a microfluidic chip is a rapid, accurate, easy, and cost-effective diagnostic test for toxigenic C. difficile in stool.
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Affiliation(s)
- Xingxing Xu
- Department of Laboratory Medicine, Zhejiang Chinese Medical University affiliated Hangzhou First Hospital, Hangzhou, Zhejiang, 310006, China; Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China
| | - Yun Luo
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China
| | - Xiaojun Song
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China
| | - Jianfei Ying
- Department of Laboratory Medicine, Ningbo Yinzhou People's Hospital, Ningbo, Zhejiang, 315040, China
| | - Julian Ye
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China
| | - Yong Lu
- Department of Laboratory Medicine, Ningbo Yinzhou People's Hospital, Ningbo, Zhejiang, 315040, China
| | - Jian Cai
- Department of Disease Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China
| | - Jian Ma
- Department of Respiratory Medicine, Ningbo Yinzhou People's Hospital, Ningbo, Zhejiang, 315040, China
| | - Xianjun Wang
- Department of Laboratory Medicine, Zhejiang Chinese Medical University affiliated Hangzhou First Hospital, Hangzhou, Zhejiang, 310006, China
| | - Wanjun Yu
- Department of Respiratory Medicine, Ningbo Yinzhou People's Hospital, Ningbo, Zhejiang, 315040, China
| | - Yiping Wang
- Department of Laboratory Medicine, Ningbo Yinzhou People's Hospital, Ningbo, Zhejiang, 315040, China
| | - Dazhi Jin
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, 310051, China.
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26
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A Rapid, Accurate, Single Molecule Counting Method Detects Clostridium difficile Toxin B in Stool Samples. Sci Rep 2018; 8:8364. [PMID: 29849171 PMCID: PMC5976643 DOI: 10.1038/s41598-018-26353-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 05/10/2018] [Indexed: 12/19/2022] Open
Abstract
We describe a new rapid and accurate immunoassay-based technology capable of counting single target molecules using digital imaging without magnification. Using the technology, we developed a rapid test for Clostridium difficile toxin B, which is responsible for the pathology underlying potentially fatal C. difficile infections (CDI). There are currently no tests for CDI that are rapid, sensitive, and specific. The MultiPath C. difficile toxin B test images and counts complexes of target-specific magnetic and fluorescent particles that have been tethered together by toxin B molecules in minimally processed stool samples. The performance characteristics of the 30 minute test include a limit of detection of 45 pg/mL, dynamic range covering 4-5 orders of magnitude, and coefficient of variation of less than 10%. The MultiPath test detected all toxinotypes and ribotypes tested, including the one most commonly occurring in the US and EU; shows no cross reactivity with relevant bacterial species; and is robust to potential interferants commonly present in stool samples. On a training set of 320 clinical stool samples, the MultiPath C. difficile toxin B test showed 97.0% sensitivity (95% CI, 91.4-99.4%); 98.3% specificity (95% CI, 96.8-99.2%); and 98.2% accuracy (95% CI, 96.7-99.0%) compared to the cellular cytotoxicity neutralization assay (CCNA) reference method. Based on these compelling performance characteristics, we believe the MultiPath technology can address the lack of rapid, sensitive, specific, and easy-to-use diagnostic tests for C. difficile.
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27
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Peng Z, Ling L, Stratton CW, Li C, Polage CR, Wu B, Tang YW. Advances in the diagnosis and treatment of Clostridium difficile infections. Emerg Microbes Infect 2018; 7:15. [PMID: 29434201 PMCID: PMC5837143 DOI: 10.1038/s41426-017-0019-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 12/22/2017] [Accepted: 12/27/2017] [Indexed: 12/14/2022]
Abstract
Clostridium difficile is a leading cause of antibiotic-associated diarrhea worldwide. The diagnosis of C. difficile infection (CDI) requires both clinical manifestations and a positive laboratory test for C. difficile and/or its toxins. While antibiotic therapy is the treatment of choice for CDI, there are relatively few classes of effective antibiotics currently available. Therefore, the development of novel antibiotics and/or alternative treatment strategies for CDI has received a great deal of attention in recent years. A number of emerging agents such as cadazolid, surotomycin, ridinilazole, and bezlotoxumab have demonstrated activity against C. difficile; some of these have been approved for limited clinical use and some are in clinical trials. In addition, other approaches such as early and accurate diagnosis of CDI as well as disease prevention are important for clinical management. While the toxigenic culture and the cell cytotoxicity neutralization assay are still recognized as the gold standard for the diagnosis of CDI, new diagnostic approaches such as nucleic acid amplification methods have become available. In this review, we will discuss both current and emerging diagnostic and therapeutic modalities for CDI.
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Affiliation(s)
- Zhong Peng
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Lifen Ling
- The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, 518000, Guangdong, China
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Charles W Stratton
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Chunhui Li
- Infection Control Center, Xiangya Hospital of Central South University, Changsha, 410008, Hunan, China
| | - Christopher R Polage
- Departments of Pathology and Laboratory Medicine and Internal Medicine, University of California Davis School of Medicine, Sacramento, CA, 95817, USA
| | - Bin Wu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Yi-Wei Tang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
- Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10065, USA.
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28
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Charretier C, Saulnier A, Benair L, Armanet C, Bassard I, Daulon S, Bernigaud B, Rodrigues de Sousa E, Gonthier C, Zorn E, Vetter E, Saintpierre C, Riou P, Gaillac D. Robust real-time cell analysis method for determining viral infectious titers during development of a viral vaccine production process. J Virol Methods 2018; 252:57-64. [DOI: 10.1016/j.jviromet.2017.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 10/24/2017] [Accepted: 11/04/2017] [Indexed: 11/29/2022]
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29
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Lai H, Huang C, Cai J, Ye J, She J, Zheng Y, Wang L, Wei Y, Fang W, Wang X, Tang YW, Luo Y, Jin D. Simultaneous detection and characterization of toxigenic Clostridium difficile directly from clinical stool specimens. Front Med 2017; 12:196-205. [PMID: 29058256 DOI: 10.1007/s11684-017-0560-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 05/17/2017] [Indexed: 02/08/2023]
Abstract
We employed a multiplex polymerase chain reaction (PCR) coupled with capillary electrophoresis (mPCR-CE) targeting six Clostridium difficile genes, including tpi, tcdA, tcdB, cdtA, cdtB, and a deletion in tcdC for simultaneous detection and characterization of toxigenic C. difficile directly from fecal specimens. The mPCR-CE had a limit of detection of 10 colony-forming units per reaction with no cross-reactions with other related bacterial genes. Clinical validation was performed on 354 consecutively collected stool specimens from patients with suspected C. difficile infection and 45 isolates. The results were compared with a reference standard combined with BD MAX Cdiff, real-time cell analysis assay (RTCA), and mPCR-CE. The toxigenic C. difficile species were detected in 36 isolates and 45 stool specimens by the mPCR-CE, which provided a positive rate of 20.3% (81/399). The mPCR-CE had a specificity of 97.2% and a sensitivity of 96.0%, which was higher than RTCA (x2 = 5.67, P = 0.017) but lower than BD MAX Cdiff (P = 0.245). Among the 45 strains, 44 (97.8%) were determined as nonribotype 027 by the mPCR-CE, which was fully agreed with PCR ribotyping. Even though ribotypes 017 (n = 8, 17.8%), 001 (n = 6, 13.3%), and 012 (n = 7, 15.6%) were predominant in this region, ribotype 027 was an important genotype monitored routinely. The mPCR-CE provided an alternative diagnosis tool for the simultaneous detection of toxigenic C. difficile in stool and potentially differentiated between RT027 and non-RT027.
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Affiliation(s)
- Hanjiang Lai
- The First People's Hospital of Xiaoshan District, Hangzhou, 311021, China
| | - Chen Huang
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Jian Cai
- Department of Disease Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Julian Ye
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China
| | - Jun She
- The First People's Hospital of Xiaoshan District, Hangzhou, 311021, China
| | - Yi Zheng
- Biotherapy Center for Medical Oncology, the First Affiliated Hospital, Zhejiang University, Hangzhou, 310003, China
| | - Liqian Wang
- Department of Laboratory Medicine, Hangzhou First People's Hospital, Hangzhou, 310006, China
| | - Yelin Wei
- The First People's Hospital of Xiaoshan District, Hangzhou, 311021, China
| | - Weijia Fang
- Biotherapy Center for Medical Oncology, the First Affiliated Hospital, Zhejiang University, Hangzhou, 310003, China
| | - Xianjun Wang
- Department of Laboratory Medicine, Hangzhou First People's Hospital, Hangzhou, 310006, China
| | - Yi-Wei Tang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.,Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, New York, NY, 10065, USA
| | - Yun Luo
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China.
| | - Dazhi Jin
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051, China.
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Zheng Y, Luo Y, Lv Y, Huang C, Sheng Q, Zhao P, Ye J, Jiang W, Liu L, Song X, Tong Z, Chen W, Lin J, Tang YW, Jin D, Fang W. Clostridium difficile colonization in preoperative colorectal cancer patients. Oncotarget 2017; 8:11877-11886. [PMID: 28060753 PMCID: PMC5355311 DOI: 10.18632/oncotarget.14424] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 12/20/2016] [Indexed: 01/05/2023] Open
Abstract
The entire process of Clostridium difficile colonization to infection develops in large intestine. However, the real colonization pattern of C. difficile in preoperative colorectal cancer patients has not been studied. In this study, 33 C. difficile strains (16.1%) were isolated from stool samples of 205 preoperative colorectal cancer patients. C. difficile colonization rates in lymph node metastasis patients (22.3%) were significantly higher than lymph node negative patients (10.8%) (OR=2.314, 95%CI=1.023-5.235, P =0.025). Meanwhile, patients positive for stool occult blood had lower C. difficile colonization rates than negative patients (11.5% vs. 24.0%, OR=0.300, 95%CI=0.131-0.685, P =0.019). A total of 16 sequence types were revealed by multilocus sequence typing. Minimum spanning tree and time-space cluster analysis indicated that all C. difficile isolates were epidemiologically unrelated. Antibiotic susceptibility testing showed all isolates were susceptible to vancomycin and metronidazole. The results suggested that the prevalence of C. difficile colonization is high in preoperative colorectal cancer patients, and the colonization is not acquired in the hospital. Since lymph node metastasis colorectal cancer patients inevitably require adjuvant chemotherapy and C. difficile infection may halt the ongoing treatment, the call for sustained monitoring of C. difficile in those patients is apparently urgent.
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Affiliation(s)
- Yi Zheng
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yun Luo
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | | | - Chen Huang
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Qinsong Sheng
- Department of Colorectal Surgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Peng Zhao
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Julian Ye
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Weiqin Jiang
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Lulu Liu
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiaojun Song
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Zhou Tong
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Wenbin Chen
- Department of Colorectal Surgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jianjiang Lin
- Department of Colorectal Surgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yi-Wei Tang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center; Department of Pathology and Medicine, Weill Medical College of Cornell University, New York, NY, USA
| | - Dazhi Jin
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Weijia Fang
- Cancer Biotherapy Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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Cytokines Are Markers of the Clostridium difficile-Induced Inflammatory Response and Predict Disease Severity. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00037-17. [PMID: 28592627 DOI: 10.1128/cvi.00037-17] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 05/24/2017] [Indexed: 12/25/2022]
Abstract
The host immune response affects pathogen virulence in Clostridium difficile infection (CDI). Thus, cytokine responses to CDI likely are associated with disease initiation and progression. Understanding the molecular drivers of inflammation and biochemical markers of disease severity is important for developing novel therapies and predicting disease prognosis. In this study, we investigated cytokine production in patients with CDI and evaluated the potential of cytokines to serve as biomarkers for CDI and predictors of disease severity. The systemic cytokine profiles of 36 CDI patients (20 with severe disease) and 8 healthy donors and the toxin-induced cytokine profiles of peripheral blood mononuclear cells (PBMC) were determined. Further, we evaluated glucosyltransferase (GT) activity in regulation of toxin-induced cytokine expression. We found upregulation of the majority of measured cytokines (11/20, 55%) in CDI patients. Interleukin-1β (IL-1β), IL-6, IL-8, IL-17A, and IL-16 were the most upregulated. High serum levels of IL-2 and IL-15 were associated with a poor prognosis in CDI patients, whereas high levels of IL-5 and gamma interferon (IFN-γ) were associated with less severe disease. Both TcdA and TcdB were potent inducers of cytokine responses, as demonstrated by stimulation of a greater number and amount of cytokines. In addition to confirming prior reports on the role of IL-8, IL-1β, and IL-6 in CDI, our data suggest that IL-16 and IL-17A, as well as the IL-1β/Th17 axis, play a key role in driving inflammatory responses in CDI. A functional GT domain of C. difficile toxins was required for the induction of a majority of cytokines investigated.
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Sun J, Ning D, Cai W, Zhou H, Zhang H, Guan D, Wu D. Evaluation of a real-time impedance analysis platform on fungal infection. J Microbiol Methods 2017; 136:88-93. [PMID: 28323067 DOI: 10.1016/j.mimet.2017.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/16/2017] [Accepted: 03/16/2017] [Indexed: 11/29/2022]
Abstract
End-point assays of in vitro cell proliferation and death have been employed to study the mechanisms of fungal pathogenesis and have shown the responses of host cells at individual time points. A new cell analysis technology has been developed that allows for the continuous measurement and quantification of cell activities, thus enabling the dynamic assessment of electrical impedance when various pathogens are cultured in vitro. In this study, this system was evaluated to determine the response of the cell line RAW264.7 to infection by several clinically relevant fungi in vitro, including Aspergillus fumigatus, Candida albicans, and melanized and albino mutant strains of Fonsecaea monophora. The results showed that infection resulted in rounding of the host cells with a loss of contact between individual cells and a decline in the electrical impedance of all test groups. However, changes in the electrical impedance were variable. Aspergillus fumigatus caused initial increases and later significant decreases in the electrical impedance, while for C. albicans and F. monophora, the effect was reduced. The melanized strain of F. monophora caused a faster change in the electrical impedance than the albino strain. Our data proved that this system can be used as an efficient tool for monitoring cellular responses to fungal infection.
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Affiliation(s)
- Jiufeng Sun
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Dan Ning
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Wenying Cai
- Department of Dermatology, Sun Yat Sen Memorial Hospital, Sun Yat Sen University, Guangzhou, China
| | - Huiqiong Zhou
- Key Laboratory for Repository and Application of Pathogenic Microbiology, Research Center for Pathogens Detection Technology of Emerging Infectious Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China; WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, China
| | - Huan Zhang
- Key Laboratory for Repository and Application of Pathogenic Microbiology, Research Center for Pathogens Detection Technology of Emerging Infectious Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China; WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, China
| | - Dawei Guan
- Key Laboratory for Repository and Application of Pathogenic Microbiology, Research Center for Pathogens Detection Technology of Emerging Infectious Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China; WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, China
| | - De Wu
- Key Laboratory for Repository and Application of Pathogenic Microbiology, Research Center for Pathogens Detection Technology of Emerging Infectious Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China; WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, China.
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Point-Counterpoint: What Is the Optimal Approach for Detection of Clostridium difficile Infection? J Clin Microbiol 2017; 55:670-680. [PMID: 28077697 DOI: 10.1128/jcm.02463-16] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTIONIn 2010, we published an initial Point-Counterpoint on the laboratory diagnosis of Clostridium difficile infection (CDI). At that time, nucleic acid amplification tests (NAATs) were just becoming commercially available, and the idea of algorithmic approaches to CDI was being explored. Now, there are numerous NAATs in the marketplace, and based on recent proficiency test surveys, they have become the predominant method used for CDI diagnosis in the United States. At the same time, there is a body of literature that suggests that NAATs lack clinical specificity and thus inflate CDI rates. Hospital administrators are taking note of institutional CDI rates because they are publicly reported. They have become an important metric impacting hospital safety ratings and value-based purchasing; hospitals may have millions of dollars of reimbursement at risk. In this Point-Counterpoint using a frequently asked question approach, Ferric Fang of the University of Washington, who has been a consistent advocate for a NAAT-only approach for CDI diagnosis, will discuss the value of a NAAT-only approach, while Christopher Polage of the University of California Davis and Mark Wilcox of Leeds University, Leeds, United Kingdom, each of whom has recently written important articles on the value of toxin detection in the diagnosis, will discuss the impact of toxin detection in CDI diagnosis.
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34
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Zhang X, Zhang K, Haag R. Multi-stage, charge conversional, stimuli-responsive nanogels for therapeutic protein delivery. Biomater Sci 2017; 3:1487-96. [PMID: 26288853 DOI: 10.1039/c5bm00171d] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A boronate ester crosslinked zwitterionic nanogel (NGCA) with ATP/pH-sensitivity has been developed with an inverse nanoprecipitation technique to achieve a two-stage charge conversion that responds to tumor extracellular conditions (pH 6.5-6.8) and an intracellular acidic environment (pH 5-6). Cationic cytochrome C (CC), a therapeutic protein, has been encapsulated into NGCA through inverse nanoprecipitation via electrostatic interactions to form protein-loaded nanogel (NGCA-CC). By adjusting the ratio of the amino and carboxyl groups in the nanogels, negatively charged nanogels that are safer under physiological conditions (pH 7.4) can convert their surface charge to positive at tumor extracellular pH, which enhance their cellular uptake efficiency. The citraconic amide formed from citraconic anhydride and amine can be cleaved in the intracellular acidic organelles to expose more amino groups and facilitate endosomal escape. The release of CC is accelerated in the presence of 5 mM ATP or under acidic conditions. Confocal laser scanning microscopy (CLSM) and flow cytometry have shown that NGCA-CC's cell uptake is higher at pH 6.5 than at pH 7.4. MTT and real-time cell analysis (RTCA) have illustrated that there is more toxicity at pH 6.5 than at pH 7.4. The apoptosis process induced by CC was determined by flow cytometry.
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Affiliation(s)
- Xuejiao Zhang
- Freie Universität Berlin, Institut für Chemie und Biochemie, Takustraße 3, 14195 Berlin, Germany.
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35
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Aljarallah KM. Conventional and alternative treatment approaches for Clostridium difficile infection. Int J Health Sci (Qassim) 2017; 11:1-10. [PMID: 28293151 PMCID: PMC5327666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Clostridium difficile-associated disease continues to be one of the leading health concerns worldwide. C. difficile is considered as a causative agent of nosocomial diarrhea that causes serious infection, which may result in death. The incidences of C. difficile infection (CDI) in developed countries have become increasingly high which may be attributed to the emergence of newer epidemic strains, extensive use of antibiotics, and limited alternative therapies. The available treatment options against CDI are expensive and promote resistance. Therefore, there is urgent need for new approaches to meet these challenges. This review discusses the current understanding of CDI, the existing clinical treatment strategies and future potential options as antidifficile agents based on the available published works.
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Affiliation(s)
- Khalid M. Aljarallah
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Majmaah, KSA,Address for correspondence: Dr. Khalid M. Aljarallah, Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Majmaah University, Majmaah, KSA. E-mail:
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36
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Murphy D, Ricci A, Auce Z, Beechinor JG, Bergendahl H, Breathnach R, Bureš J, Duarte Da Silva JP, Hederová J, Hekman P, Ibrahim C, Kozhuharov E, Kulcsár G, Lander Persson E, Lenhardsson JM, Mačiulskis P, Malemis I, Markus-Cizelj L, Michaelidou-Patsia A, Nevalainen M, Pasquali P, Rouby JC, Schefferlie J, Schlumbohm W, Schmit M, Spiteri S, Srčič S, Taban L, Tiirats T, Urbain B, Vestergaard EM, Wachnik-Święcicka A, Weeks J, Zemann B, Allende A, Bolton D, Chemaly M, Fernandez Escamez PS, Girones R, Herman L, Koutsoumanis K, Lindqvist R, Nørrung B, Robertson L, Ru G, Sanaa M, Simmons M, Skandamis P, Snary E, Speybroeck N, Ter Kuile B, Wahlström H, Baptiste K, Catry B, Cocconcelli PS, Davies R, Ducrot C, Friis C, Jungersen G, More S, Muñoz Madero C, Sanders P, Bos M, Kunsagi Z, Torren Edo J, Brozzi R, Candiani D, Guerra B, Liebana E, Stella P, Threlfall J, Jukes H. EMA and EFSA Joint Scientific Opinion on measures to reduce the need to use antimicrobial agents in animal husbandry in the European Union, and the resulting impacts on food safety (RONAFA). EFSA J 2017; 15:e04666. [PMID: 32625259 PMCID: PMC7010070 DOI: 10.2903/j.efsa.2017.4666] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
EFSA and EMA have jointly reviewed measures taken in the EU to reduce the need for and use of antimicrobials in food-producing animals, and the resultant impacts on antimicrobial resistance (AMR). Reduction strategies have been implemented successfully in some Member States. Such strategies include national reduction targets, benchmarking of antimicrobial use, controls on prescribing and restrictions on use of specific critically important antimicrobials, together with improvements to animal husbandry and disease prevention and control measures. Due to the multiplicity of factors contributing to AMR, the impact of any single measure is difficult to quantify, although there is evidence of an association between reduction in antimicrobial use and reduced AMR. To minimise antimicrobial use, a multifaceted integrated approach should be implemented, adapted to local circumstances. Recommended options (non-prioritised) include: development of national strategies; harmonised systems for monitoring antimicrobial use and AMR development; establishing national targets for antimicrobial use reduction; use of on-farm health plans; increasing the responsibility of veterinarians for antimicrobial prescribing; training, education and raising public awareness; increasing the availability of rapid and reliable diagnostics; improving husbandry and management procedures for disease prevention and control; rethinking livestock production systems to reduce inherent disease risk. A limited number of studies provide robust evidence of alternatives to antimicrobials that positively influence health parameters. Possible alternatives include probiotics and prebiotics, competitive exclusion, bacteriophages, immunomodulators, organic acids and teat sealants. Development of a legislative framework that permits the use of specific products as alternatives should be considered. Further research to evaluate the potential of alternative farming systems on reducing AMR is also recommended. Animals suffering from bacterial infections should only be treated with antimicrobials based on veterinary diagnosis and prescription. Options should be reviewed to phase out most preventive use of antimicrobials and to reduce and refine metaphylaxis by applying recognised alternative measures.
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Molecular Epidemiology of Clostridium difficile Infection in Hospitalized Patients in Eastern China. J Clin Microbiol 2016; 55:801-810. [PMID: 27974547 DOI: 10.1128/jcm.01898-16] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 12/09/2016] [Indexed: 12/18/2022] Open
Abstract
Few studies on risk factors for and transmission of Clostridium difficile infection (CDI) in China have been reported. A cross-sectional study was conducted for 3 years in eastern China. Consecutive stool specimens from hospitalized patients with diarrhea were cultured for C. difficile. C. difficile isolates from these patients then were analyzed for toxin genes, genotypes, and antimicrobial resistance. A severity score for the CDI in each patient was determined by a blinded review of the medical record, and these scores ranged from 1 to 6. A total of 397 out of 3,953 patients (10.0%) with diarrhea were found to have CDI. Severity of CDI was mild to moderate, and the average (± standard deviation) severity score was 2.61 ± 1.01. C. difficile was isolated from stool specimens in 432 (10.9%) of all the patients who had diarrhea. C. difficile genotypes were determined by multilocus sequence analysis and PCR ribotyping; sequence type 37 (ST37)/ribotype 017 (RT017) (n = 68, 16.5%) was the dominant genotype. Eleven patients (16.2%) with this genotype had a CDI severity score of 5. Overall, three RTs and four STs were predominant; these genotypes were associated with significantly different antimicrobial resistance patterns in comparison to all genotypes (χ2 = 79.56 to 97.76; P < 0.001). Independent risk factors associated with CDI included age greater than 55 years (odds ratio [95% confidence interval], 26.80 [18.76 to 38.29]), previous hospitalization (12.42 [8.85 to 17.43]), previous antimicrobial treatment within 8 weeks (150.56 [73.11 to 310.06]), hospital stay more than 3 days before sampling (2.34 [1.71 to 3.22]), undergoing chemotherapy (3.31 [2.22 to 4.92]), and undergoing abdominal surgery (4.82 [3.54 to 6.55]). CDI is clearly a problem in eastern China and has a prevalence of 10.0% in hospitalized patients. Among risk factors for CDI, the advanced age threshold was younger for Chinese patients than that reported for patients in developed countries.
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38
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Yang Y, Achazi K, Jia Y, Wei Q, Haag R, Li J. Complex Assembly of Polymer Conjugated Mesoporous Silica Nanoparticles for Intracellular pH-Responsive Drug Delivery. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:12453-12460. [PMID: 27467698 DOI: 10.1021/acs.langmuir.6b01845] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
There is a great challenge in constructing pH-responsive drug delivery systems in biomedical application research. Many nanocomposites are intended to be pH-responsive as drug carriers because of a tumorous or intracellular mildly acidic environment. However, it is always difficult to find an appropriate system for quick response and release before the carrier is excreted from the living system. In this work, hyperbranched polymer, hyperbranched polyglycerol (hPG), and conjugated mesoporous silica nanoparticles (MSNs) were assembled as complexes to serve as drug carriers. Herein, the conjugated polymer-MSNs interacted through the Schiff base bond, which possessed a mildly acidic responsive property. Interestingly, the assembled system could rapidly respond and release guest molecules inside cancer cells. This would make the entrapped drug released before the carriers escape from the endosome counterpart. The results show that the assembled composite complexes can be considered to be a drug delivery system for cancer therapy.
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Affiliation(s)
- Yang Yang
- CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology , Beijing 100190, China
| | - Katharina Achazi
- Department of Chemistry and Biochemistry, Freie Universität Berlin , Takustrasse 3, 14195 Berlin, Germany
| | - Yi Jia
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Colloid and Interface Science, Institute of Chemistry, Chinese Academy of Sciences (CAS) , Beijing 100190, China
| | - Qiang Wei
- Department of Chemistry and Biochemistry, Freie Universität Berlin , Takustrasse 3, 14195 Berlin, Germany
| | - Rainer Haag
- Department of Chemistry and Biochemistry, Freie Universität Berlin , Takustrasse 3, 14195 Berlin, Germany
| | - Junbai Li
- CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology , Beijing 100190, China
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Colloid and Interface Science, Institute of Chemistry, Chinese Academy of Sciences (CAS) , Beijing 100190, China
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39
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Tao L, Zhang J, Meraner P, Tovaglieri A, Wu X, Gerhard R, Zhang X, Stallcup WB, Miao J, He X, Hurdle JG, Breault DT, Brass AL, Dong M. Frizzled proteins are colonic epithelial receptors for C. difficile toxin B. Nature 2016; 538:350-355. [PMID: 27680706 PMCID: PMC5519134 DOI: 10.1038/nature19799] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 08/26/2016] [Indexed: 02/06/2023]
Abstract
Clostridium difficile toxin B (TcdB) is a critical virulence factor that causes diseases associated with C. difficile infection. Here we carried out CRISPR-Cas9-mediated genome-wide screens and identified the members of the Wnt receptor frizzled family (FZDs) as TcdB receptors. TcdB binds to the conserved Wnt-binding site known as the cysteine-rich domain (CRD), with the highest affinity towards FZD1, 2 and 7. TcdB competes with Wnt for binding to FZDs, and its binding blocks Wnt signalling. FZD1/2/7 triple-knockout cells are highly resistant to TcdB, and recombinant FZD2-CRD prevented TcdB binding to the colonic epithelium. Colonic organoids cultured from FZD7-knockout mice, combined with knockdown of FZD1 and 2, showed increased resistance to TcdB. The colonic epithelium in FZD7-knockout mice was less susceptible to TcdB-induced tissue damage in vivo. These findings establish FZDs as physiologically relevant receptors for TcdB in the colonic epithelium.
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Affiliation(s)
- Liang Tao
- Department of Urology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Microbiology and Immunobiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Jie Zhang
- Department of Urology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Microbiology and Immunobiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Paul Meraner
- Department of Microbiology and Physiological Systems (MaPS), University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
| | - Alessio Tovaglieri
- Division of Endocrinology, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - Xiaoqian Wu
- Center for Infectious and Inflammatory Diseases, Texas A &M Health Science Center, Houston, Texas 77030, USA
| | - Ralf Gerhard
- Institute of Toxicology, Hannover Medical School, 30625 Hannover, Germany
| | - Xinjun Zhang
- The F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - William B Stallcup
- Tumor Microenvironment and Cancer Immunology Program, Sanford-Burnham Prebys Medical Discovery Institute, Cancer Center, La Jolla, California 92037, USA
| | - Ji Miao
- Division of Endocrinology, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Xi He
- The F. M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Julian G Hurdle
- Center for Infectious and Inflammatory Diseases, Texas A &M Health Science Center, Houston, Texas 77030, USA
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02115, USA.,Harvard Stem Cell Institute, Cambridge, Massachusetts 02138, USA
| | - Abraham L Brass
- Department of Microbiology and Physiological Systems (MaPS), University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.,Gastroenterology Division, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
| | - Min Dong
- Department of Urology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Microbiology and Immunobiology and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115, USA
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An investigation of the antibacterial ability and cytotoxicity of a novel cu-bearing 317L stainless steel. Sci Rep 2016; 6:29244. [PMID: 27385507 PMCID: PMC4935851 DOI: 10.1038/srep29244] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 06/14/2016] [Indexed: 11/08/2022] Open
Abstract
In order to solve the challenging problem of microbial infections caused by microorganisms on medical implants, it is imperative to develop novel antimicrobial biomaterials. This work demonstrated that 317L-Cu stainless steel (SS), created by adding copper through a solution and aging heat treatment process, exhibited good antibacterial properties against staphylococcus aureus, achieving 2 log reduction of planktonic cells after 5 days of incubation. In this study, the antibacterial test was performed using the plate count method, the fluorescence cell staining method and the quantitative polymerase chain reaction (qPCR) method. It is well known that a high concentration of copper ion can lead to cytotoxicity. This work explored the cytotoxicity of 317L-Cu SS through real-time cell analysis (RTCA). Experimental results demonstrated that the 317L-Cu SS possessed a satisfactory antibacterial ability against S. aureus, and the antibacterial rate based on the reduction of sessile cell count reached 98.3% after 24-hour treatment. The bacterial adhesion and the biofilm thickness were considerably reduced by the 317L-Cu SS. The results of RTCA suggested that 317L-Cu SS did not introduce cytotoxicity to mouse cells, indicating its suitability as a medical implant material.
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Frädrich C, Beer LA, Gerhard R. Reactive Oxygen Species as Additional Determinants for Cytotoxicity of Clostridium difficile Toxins A and B. Toxins (Basel) 2016; 8:toxins8010025. [PMID: 26797634 PMCID: PMC4728547 DOI: 10.3390/toxins8010025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/07/2016] [Accepted: 01/13/2016] [Indexed: 12/18/2022] Open
Abstract
Clostridium difficile infections can induce mild to severe diarrhoea and the often associated characteristic pseudomembranous colitis. Two protein toxins, the large glucosyltransferases TcdA and TcdB, are the main pathogenicity factors that can induce all clinical symptoms in animal models. The classical molecular mode of action of these homologous toxins is the inhibition of Rho GTPases by mono-glucosylation. Rho-inhibition leads to breakdown of the actin cytoskeleton, induces stress-activated and pro-inflammatory signaling and eventually results in apoptosis of the affected cells. An increasing number of reports, however, have documented further qualities of TcdA and TcdB, including the production of reactive oxygen species (ROS) by target cells. This review summarizes observations dealing with the production of ROS induced by TcdA and TcdB, dissects pathways that contribute to this phenomenon and speculates about ROS in mediating pathogenesis. In conclusion, ROS have to be considered as a discrete, glucosyltransferase-independent quality of at least TcdB, triggered by different mechanisms.
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Affiliation(s)
- Claudia Frädrich
- Postgraduate Course for Toxicology and Environmental Toxicology, Institute for Legal Medicine, University of Leipzig, Johannisallee 28, Leipzig 04103, Germany.
| | - Lara-Antonia Beer
- Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, Hannover 30625, Germany.
| | - Ralf Gerhard
- Postgraduate Course for Toxicology and Environmental Toxicology, Institute for Legal Medicine, University of Leipzig, Johannisallee 28, Leipzig 04103, Germany.
- Institute of Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, Hannover 30625, Germany.
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Molecular Diagnostics for Clostridium difficile. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ultrasensitive Detection and Quantification of Toxins for Optimized Diagnosis of Clostridium difficile Infection. J Clin Microbiol 2015; 54:259-64. [PMID: 26659205 DOI: 10.1128/jcm.02419-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Recently developed ultrasensitive and quantitative methods for detection of Clostridium difficile toxins provide new tools for diagnosis and, potentially, for management of C. difficile infection (CDI). Compared to methods that detect toxigenic organism, ultrasensitive toxin detection may allow diagnosis of CDI with increased clinical specificity, without sacrificing clinical sensitivity; measurement of toxin levels may also provide information relevant to disease prognosis. This minireview provides an overview of these new toxin detection technologies and considers what these new tools might add to the field.
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Nicholson MR, Osgood CL, Acra SA, Edwards KM. Clostridium difficile infection in the pediatric transplant patient. Pediatr Transplant 2015; 19:792-8. [PMID: 26403484 DOI: 10.1111/petr.12578] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/07/2015] [Indexed: 12/17/2022]
Abstract
CDIs are on the rise in both hospital and community settings in adults and children. Children with cancer or a history of HSCT or SOT appear to be at higher risk for primary disease, recurrent disease, and severe outcomes when compared to children with other comorbidities. The reasons for this are not clear and no studies to date have analyzed risk factors for CDI in pediatric transplant patients. Colonization rates in children with cancer and a transplant history are also high. Determining which children are colonized with Clostridium difficile and symptomatic from another source vs. symptomatic from CDI is difficult and a clinical conundrum for the transplant physician. The use of fecal transplantation for severe or rCDI is likely safe and effective in the immunosuppressed pediatric cancer or transplant patient, but this will need to be more thoroughly studied in this patient population.
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Affiliation(s)
- Maribeth R Nicholson
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Christy L Osgood
- Division of Pediatric Hematology and Oncology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Sari A Acra
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Kathryn M Edwards
- Division of Pediatric Infectious Disease, Vanderbilt University School of Medicine, Nashville, TN, USA
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Polage CR, Gyorke CE, Kennedy MA, Leslie JL, Chin DL, Wang S, Nguyen HH, Huang B, Tang YW, Lee LW, Kim K, Taylor S, Romano PS, Panacek EA, Goodell PB, Solnick JV, Cohen SH. Overdiagnosis of Clostridium difficile Infection in the Molecular Test Era. JAMA Intern Med 2015; 175:1792-801. [PMID: 26348734 PMCID: PMC4948649 DOI: 10.1001/jamainternmed.2015.4114] [Citation(s) in RCA: 413] [Impact Index Per Article: 45.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
IMPORTANCE Clostridium difficile is a major cause of health care-associated infection, but disagreement between diagnostic tests is an ongoing barrier to clinical decision making and public health reporting. Molecular tests are increasingly used to diagnose C difficile infection (CDI), but many molecular test-positive patients lack toxins that historically defined disease, making it unclear if they need treatment. OBJECTIVE To determine the natural history and need for treatment of patients who are toxin immunoassay negative and polymerase chain reaction (PCR) positive (Tox-/PCR+) for CDI. DESIGN, SETTING, AND PARTICIPANTS Prospective observational cohort study at a single academic medical center among 1416 hospitalized adults tested for C difficile toxins 72 hours or longer after admission between December 1, 2010, and October 20, 2012. The analysis was conducted in stages with revisions from April 27, 2013, to January 13, 2015. MAIN OUTCOMES AND MEASURES Patients undergoing C difficile testing were grouped by US Food and Drug Administration-approved toxin and PCR tests as Tox+/PCR+, Tox-/PCR+, or Tox-/PCR-. Toxin results were reported clinically. Polymerase chain reaction results were not reported. The main study outcomes were duration of diarrhea during up to 14 days of treatment, rate of CDI-related complications (ie, colectomy, megacolon, or intensive care unit care) and CDI-related death within 30 days. RESULTS Twenty-one percent (293 of 1416) of hospitalized adults tested for C difficile were positive by PCR, but 44.7% (131 of 293) had toxins detected by the clinical toxin test. At baseline, Tox-/PCR+ patients had lower C difficile bacterial load and less antibiotic exposure, fecal inflammation, and diarrhea than Tox+/PCR+ patients (P < .001 for all). The median duration of diarrhea was shorter in Tox-/PCR+ patients (2 days; interquartile range, 1-4 days) than in Tox+/PCR+ patients (3 days; interquartile range, 1-6 days) (P = .003) and was similar to that in Tox-/PCR- patients (2 days; interquartile range, 1-3 days), despite minimal empirical treatment of Tox-/PCR+ patients. No CDI-related complications occurred in Tox-/PCR+ patients vs 10 complications in Tox+/PCR+ patients (0% vs 7.6%, P < .001). One Tox-/PCR+ patient had recurrent CDI as a contributing factor to death within 30 days vs 11 CDI-related deaths in Tox+/PCR+ patients (0.6% vs 8.4%, P = .001). CONCLUSIONS AND RELEVANCE Among hospitalized adults with suspected CDI, virtually all CDI-related complications and deaths occurred in patients with positive toxin immunoassay test results. Patients with a positive molecular test result and a negative toxin immunoassay test result had outcomes that were comparable to patients without C difficile by either method. Exclusive reliance on molecular tests for CDI diagnosis without tests for toxins or host response is likely to result in overdiagnosis, overtreatment, and increased health care costs.
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Affiliation(s)
- Christopher R Polage
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento2Division of Infectious Diseases, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento
| | - Clare E Gyorke
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento
| | - Michael A Kennedy
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento
| | - Jhansi L Leslie
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento3Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor
| | - David L Chin
- Center for Healthcare Policy and Research, University of California Davis, Sacramento
| | - Susan Wang
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento5Yolo County Health Department, Woodland, California
| | - Hien H Nguyen
- Division of Infectious Diseases, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento
| | - Bin Huang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York7Department of Clinical Laboratory, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yi-Wei Tang
- Department of Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, New York8Weill Medical College of Cornell University, New York, New York
| | - Lenora W Lee
- Division of Infectious Diseases, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento
| | - Kyoungmi Kim
- Division of Biostatistics, Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento
| | - Sandra Taylor
- Division of Biostatistics, Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento
| | - Patrick S Romano
- Center for Healthcare Policy and Research, University of California Davis, Sacramento10Division of General Medicine, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento11Division of General Pediatrics, Department
| | - Edward A Panacek
- Department of Emergency Medicine, University of California Davis School of Medicine, Sacramento
| | - Parker B Goodell
- Department of Emergency Medicine, University of California Davis School of Medicine, Sacramento
| | - Jay V Solnick
- Division of Infectious Diseases, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento13Department of Medical Microbiology and Immunology, University of California Davis School of Medicine, Sacramento
| | - Stuart H Cohen
- Division of Infectious Diseases, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento
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Monitoring in real time the cytotoxic effect of Clostridium difficile upon the intestinal epithelial cell line HT29. J Microbiol Methods 2015; 119:66-73. [PMID: 26436983 DOI: 10.1016/j.mimet.2015.09.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 01/05/2023]
Abstract
The incidence and severity of Clostridium difficile infections (CDI) has been increased not only among hospitalized patients, but also in healthy individuals traditionally considered as low risk population. Current treatment of CDI involves the use of antibiotics to eliminate the pathogen, although recurrent relapses have also been reported. For this reason, the search of new antimicrobials is a very active area of research. The strategy to use inhibitors of toxin's activity has however been less explored in spite of being a promising option. In this regard, the lack of fast and reliable in vitro screening methods to search for novel anti-toxin drugs has hampered this approach. The aim of the current study was to develop a method to monitor in real time the cytotoxicity of C. difficile upon the human colonocyte-like HT29 line, since epithelial intestinal cells are the primary targets of the toxins. The label-free, impedance based RCTA (real time cell analyser) technology was used to follow overtime the behaviour of HT29 in response to C. difficile LMG21717 producing both A and B toxins. Results obtained showed that the selection of the medium to grow the pathogen had a great influence in obtaining toxigenic supernatants, given that some culture media avoided the release of the toxins. A cytotoxic dose- and time-dependent effect of the supernatant obtained from GAM medium upon HT29 and Caco2 cells was detected. The sigmoid-curve fit of data obtained with HT29 allowed the calculation of different toxicological parameters, such as EC50 and LOAEL values. Finally, the modification in the behaviour of HT29 reordered in the RTCA was correlated with the cell rounding effect, typically induced by these toxins, visualized by time-lapsed captures using an optical microscope. Therefore, this RTCA method developed to test cytotoxicity kinetics of C. difficile supernatants upon IEC could be a valuable in vitro model for the screening of new anti-CDI agents.
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Development and Validation of Digital Enzyme-Linked Immunosorbent Assays for Ultrasensitive Detection and Quantification of Clostridium difficile Toxins in Stool. J Clin Microbiol 2015. [PMID: 26202120 DOI: 10.1128/jcm.01334-15] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The currently available diagnostics for Clostridium difficile infection (CDI) have major limitations. Despite mounting evidence that toxin detection is paramount for diagnosis, conventional toxin immunoassays are insufficiently sensitive and cytotoxicity assays too complex; assays that detect toxigenic organisms (toxigenic culture [TC] and nucleic acid amplification testing [NAAT]) are confounded by asymptomatic colonization by toxigenic C. difficile. We developed ultrasensitive digital enzyme-linked immunosorbent assays (ELISAs) for toxins A and B using single-molecule array technology and validated the assays using (i) culture filtrates from a panel of clinical C. difficile isolates and (ii) 149 adult stool specimens already tested routinely by NAAT. The digital ELISAs detected toxins A and B in stool with limits of detection of 0.45 and 1.5 pg/ml, respectively, quantified toxins across a 4-log range, and detected toxins from all clinical strains studied. Using specimens that were negative by cytotoxicity assay/TC/NAAT, clinical cutoffs were set at 29.4 pg/ml (toxin A) and 23.3 pg/ml (toxin B); the resulting clinical specificities were 96% and 98%, respectively. The toxin B digital ELISA was 100% sensitive versus cytotoxicity assay. Twenty-five percent and 22% of the samples positive by NAAT and TC, respectively, were negative by the toxin B digital ELISA, consistent with the presence of organism but minimal or no toxin. The mean toxin levels by digital ELISA were 1.5- to 1.7-fold higher in five patients with CDI-attributable severe outcomes, versus 68 patients without, but this difference was not statistically significant. Ultrasensitive digital ELISAs for the detection and quantification of toxins A and B in stool can provide a rapid and simple tool for the diagnosis of CDI with both high analytical sensitivity and high clinical specificity.
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Affiliation(s)
- Krishna Rao
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Veterans Affairs Ann Arbor Healthcare System
| | - Vincent B Young
- Division of Infectious Diseases, Department of Internal Medicine, University of Michigan Department of Microbiology and Immunology, University of Michigan, Ann Arbor
| | - David M Aronoff
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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Rao K, Micic D, Natarajan M, Winters S, Kiel MJ, Walk ST, Santhosh K, Mogle JA, Galecki AT, LeBar W, Higgins PDR, Young VB, Aronoff DM. Clostridium difficile ribotype 027: relationship to age, detectability of toxins A or B in stool with rapid testing, severe infection, and mortality. Clin Infect Dis 2015; 61:233-41. [PMID: 25828993 DOI: 10.1093/cid/civ254] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 02/18/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Clostridium difficile infection (CDI) can cause severe disease and death, especially in older adults. A better understanding of risk factors for adverse outcomes is needed. This study tests the hypotheses that infection with specific ribotypes and presence of stool toxins independently associate with severity and constructs predictive models of adverse outcomes. METHODS Cases of non-recurrent CDI were prospectively included after positive stool tests for toxins A and/or B by enzyme immunoassay (EIA) or tcdB by polymerase chain reaction. Outcomes included severe CDI (intensive care unit admission, colectomy, or death attributable to CDI within 30 days of diagnosis) and 30-day all-cause mortality. Adjusted models were developed to test hypotheses and predict outcomes. RESULTS In total, 1144 cases were included. The toxin EIA was positive in 37.2% and 35.6% of patients were of age >65 years. One of the 137 unique ribotypes was ribotype 027 (16.2%). Detectable stool toxin did not associate with outcomes. Adjusting for covariates, including age, Ribotype 027 was a significant predictor of severe CDI (90 cases; odds ratio [OR], 1.73; 95% confidence interval [CI], 1.03-2.89; P = .037) and mortality (89 cases; OR, 2.02; 95% CI, 1.19-3.43; P = .009). Concurrent antibiotic use associated with both outcomes. Both multivariable predictive models had excellent performance (area under the curve >0.8). CONCLUSIONS Detection of stool toxin A and/or B by EIA does not predict severe CDI or mortality. Infection with ribotype 027 independently predicts severe CDI and mortality. Use of concurrent antibiotics is a potentially modifiable risk factor for severe CDI.
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Affiliation(s)
- Krishna Rao
- Division of Infectious Diseases Department of Internal Medicine Division of Infectious Diseases, Veterans Affairs Ann Arbor Healthcare System, Michigan
| | - Dejan Micic
- Department of Internal Medicine, Section of Gastroenterology, Hepatology, and Nutrition, University of Chicago, Illinois
| | | | | | | | - Seth T Walk
- Department of Microbiology and Immunology, Montana State University, Bozeman
| | | | - Jill A Mogle
- Division of Infectious Diseases Department of Internal Medicine
| | - Andrzej T Galecki
- Division of Geriatric Medicine Department of Biostatistics, University of Michigan School of Medicine, Ann Arbor
| | | | | | - Vincent B Young
- Division of Infectious Diseases Department of Internal Medicine Department of Microbiology and Immunology
| | - David M Aronoff
- Division of Infectious Diseases Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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Zhang X, Achazi K, Haag R. Boronate cross-linked ATP- and pH-responsive nanogels for intracellular delivery of anticancer drugs. Adv Healthc Mater 2015; 4:585-92. [PMID: 25388994 DOI: 10.1002/adhm.201400550] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 10/08/2014] [Indexed: 11/09/2022]
Abstract
A novel adenosine-5'-triphosphate (ATP) and pH dual-responsive degradable nanogel (NG) system are developed based on the complexation of 1,2-diols in dendritic polyglycerol (dPG), and boronic acids, which are conjugated with dPG as the macromolecular cross-linker. The NG is formed by a mild and surfactant-free inverse nanoprecipitation method. An anticancer drug, methotrexate (MTX), is coprecipitated with the macromolecular precursors and cross-linkers to form MTX-loaded NG (NG-MTX) with a loading capacity of 13 wt%. The size of NG is controllable from 100 to 300 nm, which is suitable for the enhanced permeation and retention (EPR) effect and can be degraded into small fragments that are within the clearance limitation in the presence of 5 × 10(-3) m ATP or at pH 4 after 24 h. Increasing ATP concentrations and decreasing pH values of the release medium accelerate the release of MTX. Both the real-time cell analysis (RTCA) and MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) results show no cytotoxic effect of NG and a dose-dependent effect of NG-MTX on HeLa cells as well as MCF-7 cells. The fluorescein isothiocyanate (FITC)-labeled NG (FITC-NG) exhibits a time-dependent intracellular uptake tendency and cell organelle permeability as determined by confocal laser scanning microscopy (CLSM) or flow cytometry.
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Affiliation(s)
- Xuejiao Zhang
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustraße 3 14195 Berlin Germany
| | - Katharina Achazi
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustraße 3 14195 Berlin Germany
| | - Rainer Haag
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustraße 3 14195 Berlin Germany
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