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Sharafutdinov I, Tegtmeyer N, Rohde M, Olofsson A, Rehman ZU, Arnqvist A, Backert S. Campylobacter jejuni Surface-Bound Protease HtrA, but Not the Secreted Protease nor Protease in Shed Membrane Vesicles, Disrupts Epithelial Cell-to-Cell Junctions. Cells 2024; 13:224. [PMID: 38334616 PMCID: PMC10854787 DOI: 10.3390/cells13030224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/01/2023] [Accepted: 01/22/2024] [Indexed: 02/10/2024] Open
Abstract
Fundamental functions of the intestinal epithelium include the digestion of food, absorption of nutrients, and its ability to act as the first barrier against intruding microbes. Campylobacter jejuni is a major zoonotic pathogen accounting for a substantial portion of bacterial foodborne illnesses. The germ colonizes the intestines of birds and is mainly transmitted to humans through the consumption of contaminated poultry meat. In the human gastrointestinal tract, the bacterium triggers campylobacteriosis that can progress to serious secondary disorders, including reactive arthritis, inflammatory bowel disease and Guillain-Barré syndrome. We recently discovered that C. jejuni serine protease HtrA disrupts intestinal epithelial barrier functions via cleavage of the tight and adherens junction components occludin, claudin-8 and E-cadherin. However, it is unknown whether epithelial damage is mediated by the secreted soluble enzyme, by HtrA contained in shed outer-membrane vesicles (OMVs) or by another mechanism that has yet to be identified. In the present study, we investigated whether soluble recombinant HtrA and/or purified OMVs induce junctional damage to polarized intestinal epithelial cells compared to live C. jejuni bacteria. By using electron and confocal immunofluorescence microscopy, we show that HtrA-expressing C. jejuni bacteria trigger efficient junctional cell damage, but not soluble purified HtrA or HtrA-containing OMVs, not even at high concentrations far exceeding physiological levels. Instead, we found that only bacteria with active protein biosynthesis effectively cleave junctional proteins, which is followed by paracellular transmigration of C. jejuni through the epithelial cell layer. These findings shed new light on the pathogenic activities of HtrA and virulence strategies of C. jejuni.
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Affiliation(s)
- Irshad Sharafutdinov
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058 Erlangen, Germany
| | - Nicole Tegtmeyer
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058 Erlangen, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Inhoffenstraße 7, D-38124 Braunschweig, Germany
| | - Annelie Olofsson
- Department of Medical Biochemistry and Biophysics, Umeå University, SE-901 87 Umeå, Sweden
| | - Zia ur Rehman
- Department of Medical Biochemistry and Biophysics, Umeå University, SE-901 87 Umeå, Sweden
| | - Anna Arnqvist
- Department of Medical Biochemistry and Biophysics, Umeå University, SE-901 87 Umeå, Sweden
| | - Steffen Backert
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, D-91058 Erlangen, Germany
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2
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Negretti NM, Ye Y, Malavasi LM, Pokharel SM, Huynh S, Noh S, Klima CL, Gourley CR, Ragle CA, Bose S, Looft T, Parker CT, Clair G, Adkins JN, Konkel ME. A porcine ligated loop model reveals new insight into the host immune response against Campylobacter jejuni. Gut Microbes 2020; 12:1-25. [PMID: 32887530 PMCID: PMC7524355 DOI: 10.1080/19490976.2020.1814121] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 08/12/2020] [Accepted: 08/17/2020] [Indexed: 02/03/2023] Open
Abstract
The symptoms of infectious diarrheal disease are mediated by a combination of a pathogen's virulence factors and the host immune system. Campylobacter jejuni is the leading bacterial cause of diarrhea worldwide due to its near-ubiquitous zoonotic association with poultry. One of the outstanding questions is to what extent the bacteria are responsible for the diarrheal symptoms via intestinal cell necrosis versus immune cell initiated tissue damage. To determine the stepwise process of inflammation that leads to diarrhea, we used a piglet ligated intestinal loop model to study the intestinal response to C. jejuni. Pigs were chosen due to the anatomical similarity between the porcine and the human intestine. We found that the abundance of neutrophil related proteins increased in the intestinal lumen during C. jejuni infection, including proteins related to neutrophil migration (neutrophil elastase and MMP9), actin reorganization (Arp2/3), and antimicrobial proteins (lipocalin-2, myeloperoxidase, S100A8, and S100A9). The appearance of neutrophil proteins also corresponded with increases of the inflammatory cytokines IL-8 and TNF-α. Compared to infection with the C. jejuni wild-type strain, infection with the noninvasive C. jejuni ∆ciaD mutant resulted in a blunted inflammatory response, with less inflammatory cytokines and neutrophil markers. These findings indicate that intestinal inflammation is driven by C. jejuni virulence and that neutrophils are the predominant cell type responding to C. jejuni infection. We propose that this model can be used as a platform to study the early immune events during infection with intestinal pathogens.
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Affiliation(s)
- Nicholas M Negretti
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Yinyin Ye
- Integrative Omics, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Lais M Malavasi
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Swechha M Pokharel
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Steven Huynh
- Produce Safety and Microbiology, United States Department of Agriculture-Agricultural Research Service, Albany, CA, USA
| | - Susan Noh
- Animal Disease Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, WA, USA
- Washington Animal Disease Diagnostic Laboratory, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Cassidy L Klima
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, USA
| | - Christopher R Gourley
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Claude A Ragle
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Santanu Bose
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Torey Looft
- Food Safety and Enteric Pathogens Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, USA
| | - Craig T Parker
- Produce Safety and Microbiology, United States Department of Agriculture-Agricultural Research Service, Albany, CA, USA
| | - Geremy Clair
- Integrative Omics, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Joshua N Adkins
- Integrative Omics, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Michael E Konkel
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
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Callahan S, Doster RS, Jackson JW, Kelley BR, Gaddy JA, Johnson JG. Induction of neutrophil extracellular traps by Campylobacter jejuni. Cell Microbiol 2020; 22:e13210. [PMID: 32329205 PMCID: PMC7354212 DOI: 10.1111/cmi.13210] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 12/14/2022]
Abstract
Campylobacter jejuni is the leading cause of bacterial-derived gastroenteritis worldwide and can lead to several post-infectious inflammatory disorders. Despite the prevalence and health impacts of the bacterium, interactions between the host innate immune system and C. jejuni remain poorly understood. To expand on earlier work demonstrating that neutrophils traffic to the site of infection in an animal model of campylobacteriosis, we identified significant increases in several predominantly neutrophil-derived proteins in the faeces of C. jejuni-infected patients, including lipocalin-2, myeloperoxidase and neutrophil elastase. In addition to demonstrating that these proteins significantly inhibited C. jejuni growth, we determined they are released during formation of C. jejuni-induced neutrophil extracellular traps (NETs). Using quantitative and qualitative methods, we found that purified human neutrophils are activated by C. jejuni and exhibit signatures of NET generation, including presence of protein arginine deiminase-4, histone citrullination, myeloperoxidase, neutrophil elastase release and DNA extrusion. Production of NETs correlated with C. jejuni phagocytosis/endocytosis and invasion of neutrophils suggesting that host- and bacterial-mediated activities are responsible for NET induction. Further, NET-like structures were observed within intestinal tissue of C. jejuni-infected ferrets. Finally, induction of NETs significantly increased human colonocyte cytotoxicity, indicating that NET formation during C. jejuni infection may contribute to observed tissue pathology. These findings provide further understanding of C. jejuni-neutrophil interactions and inflammatory responses during campylobacteriosis.
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Affiliation(s)
- Sean Callahan
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Ryan S Doster
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Centre, Nashville, Tennessee, USA
| | - Joseph W Jackson
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Brittni R Kelley
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
| | - Jennifer A Gaddy
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University Medical Centre, Nashville, Tennessee, USA
| | - Jeremiah G Johnson
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, USA
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Šimunović K, Ramić D, Xu C, Smole Možina S. Modulation of Campylobacter jejuni Motility, Adhesion to Polystyrene Surfaces, and Invasion of INT407 Cells by Quorum-Sensing Inhibition. Microorganisms 2020; 8:E104. [PMID: 31940805 PMCID: PMC7022965 DOI: 10.3390/microorganisms8010104] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/05/2020] [Accepted: 01/09/2020] [Indexed: 11/17/2022] Open
Abstract
Campylobacter jejuni is a major foodborne pathogen, and the LuxS-mediated quorum-sensing (QS) system influences its motility, biofilm formation, invasion, host colonization, and virulence. QS therefore represents a target for the control of C. jejuni. The aim of this study was to investigate the correlation of QS inhibition with changes in C. jejuni motility, adhesion to polystyrene surfaces, and adhesion to and invasion of INT407 cells. This was achieved by studying (i) the luxS-deficient mutant and (ii) treatment of C. jejuni with 20 natural extracts as six essential oils, 11 ethanolic extracts, and three pure compounds. Compared to the wild-type, the ΔluxS mutant showed decreased motility, adhesion to polystyrene surfaces, and invasion of INT407 cells. The anti-QS effects of the treatments (n = 15/20) were assayed using Vibrio harveyi BB170 bioluminescence. Moderate positive correlation was shown between C. jejuni QS reduction and reduced motility (τ = 0.492, p = 0.024), adhesion to polystyrene surfaces (τ = 0.419, p = 0.008), and invasion (r = 0.394, p = 0.068). The best overall effect was achieved with a Sedum rosea (roseroot) extract, with 96% QS reduction, a 1.41 log (96%) decrease in adhesion to polystyrene surfaces, and an 82% decrease in invasion. We show that natural extracts can reduce motility, adhesion to polystyrene surfaces, and invasion of INT407 cells by C. jejuni through modulation of the LuxS (QS) system.
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Affiliation(s)
- Katarina Šimunović
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia (D.R.)
| | - Dina Ramić
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia (D.R.)
| | - Changyun Xu
- College of Veterinary Medicine, Iowa State University, 1800 Christensen Dr, Ames, IA 50011, USA;
| | - Sonja Smole Možina
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia (D.R.)
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Sylte MJ, Johnson TA, Meyer EL, Inbody MH, Trachsel J, Looft T, Susta L, Wu Z, Zhang Q. Intestinal colonization and acute immune response in commercial turkeys following inoculation with Campylobacter jejuni constructs encoding antibiotic-resistance markers. Vet Immunol Immunopathol 2019; 210:6-14. [PMID: 30947981 DOI: 10.1016/j.vetimm.2019.02.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/28/2019] [Accepted: 02/04/2019] [Indexed: 12/17/2022]
Abstract
Consumption of contaminated poultry products is one of the main sources of human campylobacteriosis, of which Campylobacter jejuni subsp. jejuni (C. jejuni) is responsible for approximately 90% of the cases. At slaughter, the ceca of commercial chickens and turkeys are the main anatomical site where C. jejuni asymptomatically colonizes. We have previously colonized commercial turkey poults with different isolates of C. jejuni and evaluated different media to best enumerate Campylobacter from intestinal samples, but the host-response is unknown in turkeys. Enumeration of Campylobacter (colony forming units (cfu)/gram of intestinal contents) can be challenging, and can be confounded if animals are colonized with multiple species of Campylobacter. In order to precisely enumerate the C. jejuni isolate used to experimentally colonize turkeys, constructs of C. jejuni (NCTC 11,168) were tagged with different antibiotic resistance markers at the CmeF locus (chloramphenicol (CjCm) or kanamycin (CjK)). We sought to examine the kinetics of intestinal colonization using the antibiotic resistant constructs, and characterize the immune response in cecal tissue of turkeys. In vitro analysis of the tagged antibiotic-resistant constructs demonstrated no changes in motility, morphology, or adherence and invasion of INT-407 cells compared to the parent isolate NCTC 11,168. Two animal experiments were completed to evaluate intestinal colonization by the constructs. In experiment 1, three-week old poults were colonized after oral gavage for 14 days, and CjCm and CjK cfu were recovered from cecal, but not ileal contents. In experiment 2, nine-week old poults were orally inoculated with CjCm, and the abundance of CjCm cfu/g of cecal contents significantly decreased beyond 14 days after inoculation. Significant lesions were detected in CjCm colonized poults at day 2 post-colonization. Using immunohistochemistry, Campylobacter antigen was detected in between cecal villi by day 7 of CjCm colonized poults. Quantitative RT-PCR of CjCm-colonized cecal tissue demonstrated significant down-regulation of IL-1β, IL-10 and IL-13 mRNA, and significant up-regulation of IL-6, IL-8, IL-17 A, IL-22 and IFNγ mRNA on day 2, and for some on day 7 post-colonization. All differentially expressed genes were similar to mock-infected poults by day 14. These data suggest that C. jejuni induced a brief inflammatory response in the cecum of poults that quickly resolved. Results from this study provide valuable insight into host-response and persistent colonization of the turkey cecum. These findings will help to develop and test strategies to promote food safety in commercial turkeys.
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Affiliation(s)
- Matthew J Sylte
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA.
| | - Timothy A Johnson
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA; Department of Animal Sciences, Purdue University, West Lafayette, IN, USA
| | - Ella L Meyer
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA
| | - Matt H Inbody
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA
| | - Julian Trachsel
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA
| | - Torey Looft
- Food Safety and Enteric Pathogens Research Unit, U.S. Department of Agriculture, Agricultural Research Services, National Animal Disease Center, Ames, IA, USA
| | - Leonardo Susta
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Zuowei Wu
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
| | - Qijing Zhang
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA
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Looft T, Cai G, Choudhury B, Lai LX, Lippolis JD, Reinhardt TA, Sylte MJ, Casey TA. Avian Intestinal Mucus Modulates Campylobacter jejuni Gene Expression in a Host-Specific Manner. Front Microbiol 2019; 9:3215. [PMID: 30687245 PMCID: PMC6338021 DOI: 10.3389/fmicb.2018.03215] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 12/11/2018] [Indexed: 12/28/2022] Open
Abstract
Campylobacter jejuni is a leading cause of bacterial foodborne illness in humans worldwide. However, C. jejuni naturally colonizes poultry without causing pathology where it resides deep within mucus of the cecal crypts. Mucus may modulate the pathogenicity of C. jejuni in a species-specific manner, where it is pathogenic in humans and asymptomatic in poultry. Little is known about how intestinal mucus from different host species affects C. jejuni gene expression. In this study we characterized the growth and transcriptome of C. jejuni NCTC11168 cultured in defined media supplemented with or without mucus isolated from avian (chicken or turkey) or mammalian (cow, pig, or sheep) sources. C. jejuni showed substantially improved growth over defined media, with mucus from all species, showing that intestinal mucus was an energy source for C. jejuni. Seventy-three genes were differentially expressed when C. jejuni was cultured in avian vs. mammalian mucus. Genes associated with iron acquisition and resistance to oxidative stress were significantly increased in avian mucus. Many of the differentially expressed genes were flanked by differentially expressed antisense RNA asRNA, suggesting a role in gene regulation. This study highlights the interactions between C. jejuni and host mucus and the impact on gene expression, growth and invasion of host cells, suggesting important responses to environmental cues that facilitate intestinal colonization. IMPORTANCE Campylobacter jejuni infection of humans is an important health problem world-wide and is the leading bacterial cause of foodborne illnesses in U.S. The main route for exposure for humans is consumption of poultry meat contaminated during processing. C. jejuni is frequently found in poultry, residing within the mucus of the intestinal tract without causing disease. It is not clear why C. jejuni causes disease in some animals and humans, while leaving birds without symptoms. To understand its activity in birds, we characterized C. jejuni responses to poultry mucus to identify genes turned on in the intestinal tract of birds. We identified genes important for colonization and persistence within the poultry gut, turned on when C. jejuni was exposed to poultry mucus. Our findings are an important step in understanding how C. jejuni responds and interacts in the poultry gut, and may identify ways to reduce C. jejuni in birds.
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Affiliation(s)
- Torey Looft
- Food Safety and Enteric Pathogens Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, IA, United States
| | - Guohong Cai
- Crop Production and Pest Control Research Unit, United States Department of Agriculture, Agricultural Research Service, West Lafayette, IN, United States
| | - Biswa Choudhury
- GlycoAnalytics Core, University of California, San Diego, San Diego, CA, United States
| | - Lisa X Lai
- Food Safety and Enteric Pathogens Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, IA, United States
| | - John D Lippolis
- Ruminant Diseases and Immunology Research Unit, Agricultural Research Service, United States Department of Agriculture, National Animal Disease Center, Ames, IA, United States
| | - Timothy A Reinhardt
- Ruminant Diseases and Immunology Research Unit, Agricultural Research Service, United States Department of Agriculture, National Animal Disease Center, Ames, IA, United States
| | - Matthew J Sylte
- Food Safety and Enteric Pathogens Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, IA, United States
| | - Thomas A Casey
- Food Safety and Enteric Pathogens Research Unit, United States Department of Agriculture, National Animal Disease Center, Agricultural Research Service, Ames, IA, United States
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Ernstsen CL, Login FH, Jensen HH, Nørregaard R, Møller-Jensen J, Nejsum LN. Detection and quantification of intracellular bacterial colonies by automated, high-throughput microscopy. J Microbiol Methods 2017; 139:37-44. [PMID: 28477900 DOI: 10.1016/j.mimet.2017.05.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/01/2017] [Accepted: 05/03/2017] [Indexed: 10/19/2022]
Abstract
To target bacterial pathogens that invade and proliferate inside host cells, it is necessary to design intervention strategies directed against bacterial attachment, cellular invasion and intracellular proliferation. We present an automated microscopy-based, fast, high-throughput method for analyzing size and number of intracellular bacterial colonies in infected tissue culture cells. Cells are seeded in 48-well plates and infected with a GFP-expressing bacterial pathogen. Following gentamicin treatment to remove extracellular pathogens, cells are fixed and cell nuclei stained. This is followed by automated microscopy and subsequent semi-automated spot detection to determine the number of intracellular bacterial colonies, their size distribution, and the average number per host cell. Multiple 48-well plates can be processed sequentially and the procedure can be completed in one working day. As a model we quantified intracellular bacterial colonies formed by uropathogenic Escherichia coli (UPEC) during infection of human kidney cells (HKC-8). Urinary tract infections caused by UPEC are among the most common bacterial infectious diseases in humans. UPEC can colonize tissues of the urinary tract and is responsible for acute, chronic, and recurrent infections. In the bladder, UPEC can form intracellular quiescent reservoirs, thought to be responsible for recurrent infections. In the kidney, UPEC can colonize renal epithelial cells and pass to the blood stream, either via epithelial cell disruption or transcellular passage, to cause sepsis. Intracellular colonies are known to be clonal, originating from single invading UPEC. In our experimental setup, we found UPEC CFT073 intracellular bacterial colonies to be heterogeneous in size and present in nearly one third of the HKC-8 cells. This high-throughput experimental format substantially reduces experimental time and enables fast screening of the intracellular bacterial load and cellular distribution of multiple bacterial isolates. This will be a powerful experimental tool facilitating the study of bacterial invasion, drug resistance, and the development of new therapeutics.
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Affiliation(s)
- Christina L Ernstsen
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark; Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Frédéric H Login
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
| | - Helene H Jensen
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark; Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Rikke Nørregaard
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark
| | - Jakob Møller-Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Lene N Nejsum
- Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark.
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