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McCoy R, Oldroyd S, Yang W, Wang K, Hoven D, Bulmer D, Zilbauer M, Owens RM. In Vitro Models for Investigating Intestinal Host-Pathogen Interactions. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306727. [PMID: 38155358 PMCID: PMC10885678 DOI: 10.1002/advs.202306727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/01/2023] [Indexed: 12/30/2023]
Abstract
Infectious diseases are increasingly recognized as a major threat worldwide due to the rise of antimicrobial resistance and the emergence of novel pathogens. In vitro models that can adequately mimic in vivo gastrointestinal physiology are in high demand to elucidate mechanisms behind pathogen infectivity, and to aid the design of effective preventive and therapeutic interventions. There exists a trade-off between simple and high throughput models and those that are more complex and physiologically relevant. The complexity of the model used shall be guided by the biological question to be addressed. This review provides an overview of the structure and function of the intestine and the models that are developed to emulate this. Conventional models are discussed in addition to emerging models which employ engineering principles to equip them with necessary advanced monitoring capabilities for intestinal host-pathogen interrogation. Limitations of current models and future perspectives on the field are presented.
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Affiliation(s)
- Reece McCoy
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - Sophie Oldroyd
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - Woojin Yang
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
- Wellcome‐MRC Cambridge Stem Cell InstituteUniversity of CambridgeCambridgeCB2 0AWUK
| | - Kaixin Wang
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - Darius Hoven
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - David Bulmer
- Department of PharmacologyUniversity of CambridgeCambridgeCB2 1PDUK
| | - Matthias Zilbauer
- Wellcome‐MRC Cambridge Stem Cell InstituteUniversity of CambridgeCambridgeCB2 0AWUK
| | - Róisín M. Owens
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
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2
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Garvey SM, Emami NK, Guice JL, Sriranganathan N, Penet C, Rhoads RP, Spears JL, Dalloul RA, El-Kadi SW. The Probiotic Bacillus subtilis MB40 Improves Immunity in a Porcine Model of Listeriosis. Microorganisms 2023; 11:2110. [PMID: 37630670 PMCID: PMC10458092 DOI: 10.3390/microorganisms11082110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/08/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
Probiotics for humans and direct-fed microbials for livestock are increasingly popular dietary ingredients for supporting immunity. The aim of this study was to determine the effects of dietary supplementation of Bacillus subtilis MB40 (MB40) on immunity in piglets challenged with the foodborne pathogen Listeria monocytogenes (LM). Three-week-old piglets (n = 32) were randomly assigned to four groups: (1) basal diet, (2) basal diet with LM challenge, (3) MB40-supplemented diet, and (4) MB40-supplemented diet with LM challenge. Experimental diets were provided throughout a 14-day (d) period. On d8, piglets in groups 2 and 4 were intraperitoneally inoculated with LM at 108 CFU/mL per piglet. Blood samples were collected at d1, d8, and d15 for biochemical and immune response profiling. Animals were euthanized and necropsied at d15 for liver and spleen bacterial counts and intestinal morphological analysis. At d15, LM challenge was associated with increased spleen weight (p = 0.017), greater circulating populations of neutrophils (p = 0.001) and monocytes (p = 0.008), and reduced ileal villus height to crypt depth ratio (p = 0.009), compared to non-challenged controls. MB40 supplementation reduced LM bacterial counts in the liver and spleen by 67% (p < 0.001) and 49% (p < 0.001), respectively, following the LM challenge, compared to the basal diet. MB40 supplementation was also associated with decreased circulating concentrations of monocytes (p = 0.007). Altogether, these data suggest that MB40 supplementation is a safe and well-tolerated approach to enhance immunity during systemic Listeria infection.
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Affiliation(s)
- Sean M. Garvey
- Department of Research and Development, BIO-CAT, Inc., Troy, VA 22974, USA
| | - Nima K. Emami
- School of Animal Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Justin L. Guice
- Department of Research and Development, BIO-CAT, Inc., Troy, VA 22974, USA
| | | | - Christopher Penet
- Department of Research and Development, BIO-CAT, Inc., Troy, VA 22974, USA
| | - Robert P. Rhoads
- School of Animal Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Jessica L. Spears
- Department of Research and Development, BIO-CAT Microbials, LLC, Shakopee, MN 55379, USA
| | - Rami A. Dalloul
- Department of Poultry Science, University of Georgia, Athens, GA 30602, USA
| | - Samer W. El-Kadi
- School of Animal Sciences, Virginia Tech, Blacksburg, VA 24061, USA
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3
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Wanford JJ, Odendall C. Ca 2+-calmodulin signalling at the host-pathogen interface. Curr Opin Microbiol 2023; 72:102267. [PMID: 36716574 DOI: 10.1016/j.mib.2023.102267] [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: 10/19/2022] [Revised: 12/19/2022] [Accepted: 01/04/2023] [Indexed: 01/29/2023]
Abstract
Multiple eukaryotic cell processes are modulated by calcium ions (Ca2+). As such, Ca2+ is emerging as a crucial regulator of innate immunity in multicellular organisms. In particular, recent studies have identified roles of Ca2+ signalling at the host-bacteria interface. Following microbial exposure, Ca2+ signals mobilised from the extracellular milieu or intracellular stores are transduced into cell physiological responses. However, during infection with host-adapted pathogens, Ca2+ signals are often atypical, due to the activities of virulence factors, with varied consequences for both the pathogen and the host cell. In this review, we describe the Ca2+-dependent host factors regulating antibacterial immunity, in addition to bacterial effectors that promote, inhibit, or co-opt Ca2+-calmodulin signalling to promote infection.
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Affiliation(s)
- Joseph J Wanford
- School of Immunology and Microbial Sciences, Kings College London, London, UK
| | - Charlotte Odendall
- School of Immunology and Microbial Sciences, Kings College London, London, UK.
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Cegarra L, Aguirre P, Nuñez MT, Gerdtzen ZP, Salgado JC. Calcium is a noncompetitive inhibitor of DMT1 on the intestinal iron absorption process: empirical evidence and mathematical modeling analysis. Am J Physiol Cell Physiol 2022; 323:C1791-C1806. [PMID: 36342159 DOI: 10.1152/ajpcell.00411.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Iron absorption is a complex and highly controlled process where DMT1 transports nonheme iron through the brush-border membrane of enterocytes to the cytoplasm but does not transport alkaline-earth metals such as calcium. However, it has been proposed that high concentrations of calcium in the diet could reduce iron bioavailability. In this work, we investigate the effect of intracellular and extracellular calcium on iron uptake by Caco-2 cells, as determined by calcein fluorescence quenching. We found that extracellular calcium inhibits iron uptake by Caco-2 cells in a concentration-dependent manner. Chelation of intracellular calcium with BAPTA did not affect iron uptake, which indicates that the inhibitory effect of calcium is not exerted through intracellular calcium signaling. Kinetic studies performed, provided evidence that calcium acts as a reversible noncompetitive inhibitor of the iron transport activity of DMT1. Based on these experimental results, a mathematical model was developed that considers the dynamics of noncompetitive inhibition using a four-state mechanism to describe the inhibitory effect of calcium on the DMT1 iron transport process in intestinal cells. The model accurately predicts the calcein fluorescence quenching dynamics observed experimentally after an iron challenge. Therefore, the proposed model structure is capable of representing the inhibitory effect of extracellular calcium on DMT1-mediated iron entry into the cLIP of Caco-2 cells. Considering the range of calcium concentrations that can inhibit iron uptake, the possible inhibition of dietary calcium on intestinal iron uptake is discussed.
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Affiliation(s)
- Layimar Cegarra
- Laboratory of Process Modeling and Distributed Computing, Department of Chemical Engineering, Biotechnology and Materials, University of Chile, Santiago, Chile.,Mammalian Cell Culture Laboratory, Department of Chemical Engineering, Biotechnology and Materials, University of Chile, Santiago, Chile.,Centre for Biotechnology and Bioengineering, University of Chile, Santiago, Chile
| | - Pabla Aguirre
- Iron and Biology of Aging Laboratory, Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile
| | - Marco T Nuñez
- Iron and Biology of Aging Laboratory, Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile
| | - Ziomara P Gerdtzen
- Mammalian Cell Culture Laboratory, Department of Chemical Engineering, Biotechnology and Materials, University of Chile, Santiago, Chile.,Centre for Biotechnology and Bioengineering, University of Chile, Santiago, Chile.,Center of Interventional Medicine for Precision and Advanced Cellular Therapy, Santiago, Chile.,Millennium Nucleus Marine Agronomy of Seaweed Holobionts, Puerto Mont, Chile
| | - J Cristian Salgado
- Laboratory of Process Modeling and Distributed Computing, Department of Chemical Engineering, Biotechnology and Materials, University of Chile, Santiago, Chile.,Centre for Biotechnology and Bioengineering, University of Chile, Santiago, Chile
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Zouliati K, Stavropoulou P, Chountoulesi M, Naziris N, Demisli S, Mitsou E, Papadimitriou V, Chatzidaki M, Xenakis A, Demetzos C. Development and evaluation of liposomal nanoparticles incorporating dimethoxycurcumin. In vitro toxicity and permeability studies. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Kaempferol-Driven Inhibition of Listeriolysin O Pore Formation and Inflammation Suppresses Listeria monocytogenes Infection. Microbiol Spectr 2022; 10:e0181022. [PMID: 35856678 PMCID: PMC9431489 DOI: 10.1128/spectrum.01810-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Listeria monocytogenes remains a nonnegligible cause of foodborne infection, posing a critical threat to public health. Under the global antibiotic crisis, novel alternative approaches are urgently needed. The indispensable role of listeriolysin O (LLO) in the intracellular life cycle, barrier penetration, colonization, and systemic dissemination of L. monocytogenes renders it a potent drug target, which means curbing L. monocytogenes via interfering with LLO-associated pathogenic mechanisms. Here, we identified kaempferol, a natural small molecule compound, as an effective LLO inhibitor that engaged the residues Glu437, Ile468, and Tyr469 of LLO, thereby suppressing LLO-mediated membrane perforation and barrier disruption. Moreover, we found that kaempferol also suppressed host-derived inflammation in a distinct way independent of LLO inhibition. The in vivo study revealed that kaempferol treatment significantly reduced bacterial burden and cytokine burst in target organs, thereby effectively protecting mice from systemic L. monocytogenes infection. Our findings present kaempferol as a potential therapeutic application for L. monocytogenes infection, which is less likely to induce drug resistance than antibiotics because of its superiority of interfering with the pathogenesis process rather than exerting pressure on bacterial viability. IMPORTANCE Currently, we are facing a global crisis of antibiotic resistance, and novel alternative approaches are urgently needed to curb L. monocytogenes infection. Our study demonstrated that kaempferol alleviated L. monocytogenes infection via suppressing LLO pore formation and inflammation response, which might represent a novel antimicrobial-independent strategy to curb listeriosis.
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7
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Insights from Bacteroides Species in Children with Type 1 Diabetes. Microorganisms 2021; 9:microorganisms9071436. [PMID: 34361871 PMCID: PMC8306409 DOI: 10.3390/microorganisms9071436] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/24/2021] [Accepted: 06/29/2021] [Indexed: 12/11/2022] Open
Abstract
In our previous study the enrichment of the intestinal proteome of type 1 diabetes (T1D) children with Bacteroides proteins was observed, which led us to our current study that aimed to isolate and characterize Bacteroides species from fecal samples of T1D and control children. Repetitive sequence-based PCR (rep-PCR) was used for typing the isolated Bacteroides species. The antibiotic susceptibility and mucinolytic activity of the isolates was determined. The quantification of specific bacterial groups in the fecal samples was determined by qPCR. The ability to adhere and invade the human colonic cell line HT29-MTX-E12 of strains of P. dorei, B. uniformis and P. distasonis was determined and their whole genome sequencing was performed. The results showed similar numbers of Bacteroides species in T1D and control samples, but unique Bacteroides species and a higher recovery of P. distasonis from T1D samples was observed. Rep-PCR grouped the different Bacteroides species, but no discrimination by origin was achieved. T1D children showed a significant increase in Proteobacteria and a depletion in Lactobacillus sp. All tested P. dorei, B. uniformis and P. distasonis were able to adhere to HT29-MTX-E12 cells but significant differences (p < 0.05) in the ability to invade was observed. The highest ability to invade was exhibited by P. distasonis PtF D14MH1 and P. dorei PtFD16P1, while B. uniformis strains were unable to invade. The damage to tight junctions was also observed. The presence of Lactobacillus sp. inhibited the invasion ability of P. distasonis PtF D14MH1 but not P. dorei PtFD16P1. Sequences of agonist peptides of the human natural preproinsulin and the insulin B chain insB:9-23 peptide mimics were identified. The results reported in our study stresses the continued efforts required to clarify the link between T1D and gut microbiota.
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Wine Pomace Product Inhibit Listeria monocytogenes Invasion of Intestinal Cell Lines Caco-2 and SW-480. Foods 2021; 10:foods10071485. [PMID: 34206875 PMCID: PMC8304679 DOI: 10.3390/foods10071485] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/19/2021] [Accepted: 06/22/2021] [Indexed: 11/17/2022] Open
Abstract
Red wine pomace products (WPP) have antimicrobial activities against human pathogens, and it was suggested that they have a probable anti-Listeria effect. This manuscript evaluates the intestinal cell monolayer invasive capacity of Listeria monocytogenes strains obtained from human, salmon, cheese, and L. innocua treated with two WPP (WPP-N and WPP-C) of different polyphenol contents using Caco-2 and SW480 cells. The invasion was dependent of the cell line, being higher in the SW480 than in the Caco-2 cell line. Human and salmon L. monocytogenes strains caused cell invasion in both cell lines, while cheese and L. innocua did not cause an invasion. The phenolic contents of WPP-N are characterized by high levels of anthocyanin and stilbenes and WPP-C by a high content of phenolic acids. The inhibitory effect of the WPPs was dependent of the strain and of the degree of differentiation of the intestinal cells line. The inhibition of Listeria invasion by WPPs in the SW480 cell line, especially with WPP-C, were higher than the Caco-2 cell line inhibited mainly by WPP-N. This effect is associated with the WPPs’ ability to protect the integrity of the intestinal barrier by modification of the cell–cell junction protein expression. The gene expression of E-cadherin and occludin are involved in the L. monocytogenes invasion of both the Caco-2 and SW480 cell lines, while the gene expression of claudin is only involved in the invasion of SW480. These findings suggest that WPPs have an inhibitory L. monocytogenes invasion effect in gastrointestinal cells lines.
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Resnik N, Tratnjek L, Kreft ME, Kisovec M, Aden S, Bedina Zavec A, Anderluh G, Podobnik M, Veranič P. Cytotoxic Activity of LLO Y406A Is Targeted to the Plasma Membrane of Cancer Urothelial Cells. Int J Mol Sci 2021; 22:ijms22073305. [PMID: 33805017 PMCID: PMC8037347 DOI: 10.3390/ijms22073305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/19/2021] [Accepted: 03/21/2021] [Indexed: 01/01/2023] Open
Abstract
Identification of novel agents for bladder cancer treatment is highly desirable due to the high incidence of tumor recurrence and the risk of progression to muscle-invasive disease. The key feature of the cholesterol-dependent toxin listeriolysin O mutant (LLO Y406A) is its preferential activity at pH 5.7, which could be exploited either directly for selective targeting of cancer cells or the release of accumulated therapeutics from acidic endosomes. Therefore, our goal was to compare the cytotoxic effect of LLO Y406A on cancer cells (RT4) and normal urothelial cells (NPU), and to identify which cell membranes are the primary target of LLO Y406A by viability assays, life-cell imaging, fluorescence, and electron microscopy. LLO Y406A decreased viability, altered cell morphology, provoked membrane blebbing, and induced apoptosis in RT4 cells, while it did not affect NPU cells. LLO Y406A did not cause endosomal escape in RT4 cells, while the plasma membrane of RT4 cells was revealed as the primary target of LLO Y406A. It has been concluded that LLO Y406A has the ability to selectively eliminate cancer urothelial cells through pore-forming activity at the plasma membrane, without cytotoxic effects on normal urothelial cells. This promising selective activity merits further testing as an anti-cancer agent.
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Affiliation(s)
- Nataša Resnik
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (N.R.); (L.T.); (M.E.K.)
| | - Larisa Tratnjek
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (N.R.); (L.T.); (M.E.K.)
| | - Mateja Erdani Kreft
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (N.R.); (L.T.); (M.E.K.)
| | - Matic Kisovec
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia; (M.K.); (S.A.); (A.B.Z.); (G.A.); (M.P.)
| | - Saša Aden
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia; (M.K.); (S.A.); (A.B.Z.); (G.A.); (M.P.)
| | - Apolonija Bedina Zavec
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia; (M.K.); (S.A.); (A.B.Z.); (G.A.); (M.P.)
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia; (M.K.); (S.A.); (A.B.Z.); (G.A.); (M.P.)
| | - Marjetka Podobnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia; (M.K.); (S.A.); (A.B.Z.); (G.A.); (M.P.)
| | - Peter Veranič
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (N.R.); (L.T.); (M.E.K.)
- Correspondence: ; Tel.: +386-1-543-7682
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10
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The molecular mechanisms of listeriolysin O-induced lipid membrane damage. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183604. [PMID: 33722646 DOI: 10.1016/j.bbamem.2021.183604] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 12/22/2022]
Abstract
Listeria monocytogenes is an intracellular food-borne pathogen that causes listeriosis, a severe and potentially life-threatening disease. Listeria uses a number of virulence factors to proliferate and spread to various cells and tissues. In this process, three bacterial virulence factors, the pore-forming protein listeriolysin O and phospholipases PlcA and PlcB, play a crucial role. Listeriolysin O belongs to a family of cholesterol-dependent cytolysins that are mostly expressed by gram-positive bacteria. Its unique structural features in an otherwise conserved three-dimensional fold, such as the acidic triad and proline-glutamate-serine-threonine-like sequence, enable the regulation of its intracellular activity as well as distinct extracellular functions. The stability of listeriolysin O is pH- and temperature-dependent, and this provides another layer of control of its activity in cells. Moreover, many recent studies have demonstrated a unique mechanism of pore formation by listeriolysin O, i.e., the formation of arc-shaped oligomers that can subsequently fuse to form membrane defects of various shapes and sizes. During listerial invasion of host cells, these membrane defects can disrupt phagosome membranes, allowing bacteria to escape into the cytosol and rapidly multiply. The activity of listeriolysin O is profoundly dependent on the amount and accessibility of cholesterol in the lipid membrane, which can be modulated by the phospholipase PlcB. All these prominent features of listeriolysin O play a role during different stages of the L. monocytogenes life cycle by promoting the proliferation of the pathogen while mitigating excessive damage to its replicative niche in the cytosol of the host cell.
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Hosic S, Bindas AJ, Puzan ML, Lake W, Soucy JR, Zhou F, Koppes RA, Breault DT, Murthy SK, Koppes AN. Rapid Prototyping of Multilayer Microphysiological Systems. ACS Biomater Sci Eng 2020; 7:2949-2963. [PMID: 34275297 DOI: 10.1021/acsbiomaterials.0c00190] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Microfluidic organs-on-chips aim to realize more biorelevant in vitro experiments compared to traditional two-dimensional (2D) static cell culture. Often such devices are fabricated via poly(dimethylsiloxane) (PDMS) soft lithography, which offers benefits (e.g., high feature resolution) along with drawbacks (e.g., prototyping time/costs). Here, we report benchtop fabrication of multilayer, PDMS-free, thermoplastic organs-on-chips via laser cut and assembly with double-sided adhesives that overcome some limitations of traditional PDMS lithography. Cut and assembled chips are economical to prototype ($2 per chip), can be fabricated in parallel within hours, and are Luer compatible. Biocompatibility was demonstrated with epithelial line Caco-2 cells and primary human small intestinal organoids. Comparable to control static Transwell cultures, Caco-2 and organoids cultured on chips formed confluent monolayers expressing tight junctions with low permeability. Caco-2 cells-on-chip differentiated ∼4 times faster, including increased mucus, compared to controls. To demonstrate the robustness of cut and assemble, we fabricated a dual membrane, trilayer chip integrating 2D and 3D compartments with accessible apical and basolateral flow chambers. As proof of concept, we cocultured a human, differentiated monolayer and intact 3D organoids within multilayered contacting compartments. The epithelium exhibited 3D tissue structure and organoids expanded close to the adjacent monolayer, retaining proliferative stem cells over 10 days. Taken together, cut and assemble offers the capability to rapidly and economically manufacture microfluidic devices, thereby presenting a compelling fabrication technique for developing organs-on-chips of various geometries to study multicellular tissues.
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Affiliation(s)
- Sanjin Hosic
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Adam J Bindas
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Marissa L Puzan
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Will Lake
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Jonathan R Soucy
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Fanny Zhou
- Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, Massachusetts 02115, United States
| | - Ryan A Koppes
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - David T Breault
- Division of Endocrinology, Boston Children's Hospital, 300 Longwood Avenue, Boston, Massachusetts 02115, United States.,Department of Pediatrics, Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts 02115, United States.,Principal Faculty, Harvard Stem Cell Institute, 7 Divinity Ave, Cambridge, Massachusetts 02138, United States
| | - Shashi K Murthy
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
| | - Abigail N Koppes
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States.,Department of Biology, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, Massachusetts 02115, United States
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12
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Clostridium perfringens Epsilon-Toxin Impairs the Barrier Function in MDCK Cell Monolayers in a Ca 2+-Dependent Manner. Toxins (Basel) 2020; 12:toxins12050286. [PMID: 32365779 PMCID: PMC7291203 DOI: 10.3390/toxins12050286] [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: 03/27/2020] [Revised: 04/21/2020] [Accepted: 04/28/2020] [Indexed: 12/27/2022] Open
Abstract
Epsilon-toxin produced by Clostridium perfringens significantly contributes to the pathogeneses of enterotoxemia in ruminants and multiple sclerosis in humans. Epsilon-toxin forms a heptameric oligomer in the host cell membrane, promoting cell disruption. Here, we investigate the effect of epsilon-toxin on epithelial barrier functions. Epsilon-toxin impairs the barrier integrity of Madin-Darby Canine Kidney (MDCK) cells, as demonstrated by decreased transepithelial electrical resistance (TEER), increased paracellular flux marker permeability, and the decreased cellular localization of junctional proteins, such as occludin, ZO-1, and claudin-1. U73122, an endogenous phospholipase C (PLC) inhibitor, inhibited the decrease in TEER and the increase in the permeability of flux marker induced by epsilon-toxin. The application of epsilon-toxin to MDCK cells resulted in the biphasic formation of 1,2-diacylglycerol (DAG) and inositol-1,4,5-triphosphate (IP3). U73122 blocked the formation of DAG and IP3 induced by the toxin. Epsilon-toxin also specifically activated endogenous PLC-γ1. Epsilon-toxin dose-dependently increased the cytosolic calcium ion concentration ([Ca2+]i). The toxin-induced elevation of [Ca2+]i was inhibited by U73122. Cofilin is a key regulator of actin cytoskeleton turnover and tight-junction (TJ) permeability regulation. Epsilon-toxin caused cofilin dephosphorylation. These results demonstrate that epsilon-toxin induces Ca2+ influx through activating the phosphorylation of PLC-γ1 and then causes TJ opening accompanied by cofilin dephosphorylation.
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13
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Omersa N, Aden S, Kisovec M, Podobnik M, Anderluh G. Design of Protein Logic Gate System Operating on Lipid Membranes. ACS Synth Biol 2020; 9:316-328. [PMID: 31995709 PMCID: PMC7308068 DOI: 10.1021/acssynbio.9b00340] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Indexed: 12/16/2022]
Abstract
Lipid membranes are becoming increasingly popular in synthetic biology due to their biophysical properties and crucial role in communication between different compartments. Several alluring protein-membrane sensors have already been developed, whereas protein logic gates designs on membrane-embedded proteins are very limited. Here we demonstrate the construction of a two-level protein-membrane logic gate with an OR-AND logic. The system consists of an engineered pH-dependent pore-forming protein listeriolysin O and its DARPin-based inhibitor, conjugated to a lipid vesicle membrane. The gate responds to low pH and removal of the inhibitor from the membrane either by switching to a reducing environment, protease cleavage, or any other signal depending on the conjugation chemistry used for inhibitor attachment to the membrane. This unique protein logic gate vesicle system advances generic sensing and actuator platforms used in synthetic biology and could be utilized in drug delivery.
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Affiliation(s)
- Neža Omersa
- Department
of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1001 Ljubljana, Slovenia
- Biomedicine
Doctoral Program, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Saša Aden
- Department
of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1001 Ljubljana, Slovenia
- Biomedicine
Doctoral Program, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Matic Kisovec
- Department
of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1001 Ljubljana, Slovenia
| | - Marjetka Podobnik
- Department
of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1001 Ljubljana, Slovenia
| | - Gregor Anderluh
- Department
of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova ulica 19, 1001 Ljubljana, Slovenia
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14
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Novak M, Čepin U, Hodnik V, Narat M, Jamnik M, Kraševec N, Sepčić K, Anderluh G. Functional studies of aegerolysin and MACPF-like proteins in Aspergillus niger. Mol Microbiol 2019; 112:1253-1269. [PMID: 31376198 DOI: 10.1111/mmi.14360] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2019] [Indexed: 12/21/2022]
Abstract
Proteins of the aegerolysin family have a high abundance in Fungi. Due to their specific binding to membrane lipids, and their membrane-permeabilization potential in concert with protein partner(s) belonging to a membrane-attack-complex/perforin (MACPF) superfamily, they were proposed as useful tools in different biotechnological and biomedical applications. In this work, we performed functional studies on expression of the genes encoding aegerolysin and MACPF-like proteins in Aspergillus niger. Our results suggest the sporulation process being crucial for strong induction of the expression of all these genes. However, deletion of either of the aegerolysin genes did not influence the growth, development, sporulation efficiency and phenotype of the mutants, indicating that aegerolysins are not key factors in the sporulation process. In all our expression studies we noticed a strong correlation in the expression of one aegerolysin and MACPF-like gene. Aegerolysins were confirmed to be secreted from the fungus. We also showed the specific interaction of a recombinant A. niger aegerolysin with an invertebrate-specific membrane sphingolipid. Moreover, using this protein labelled with mCherry we successfully stained insect cells membranes containing this particular sphingolipid. Our combined results suggest, that aegerolysins in this species, and probably also in other aspergilli, could be involved in defence against predators.
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Affiliation(s)
- Maruša Novak
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Urška Čepin
- BioSistemika Ltd and National Institute of Biology, Ljubljana, Slovenia
| | - Vesna Hodnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Mojca Narat
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Maja Jamnik
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Nada Kraševec
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Kristina Sepčić
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
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15
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Seike S, Takehara M, Kobayashi K, Nagahama M. Clostridium perfringens Delta-Toxin Damages the Mouse Small Intestine. Toxins (Basel) 2019; 11:toxins11040232. [PMID: 31013617 PMCID: PMC6520758 DOI: 10.3390/toxins11040232] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/08/2019] [Accepted: 04/17/2019] [Indexed: 12/13/2022] Open
Abstract
Clostridium perfringens strains B and C cause fatal intestinal diseases in animals. The secreted pore-forming toxin delta-toxin is one of the virulence factors of the strains, but the mechanism of intestinal pathogenesis is unclear. Here, we investigated the effects of delta-toxin on the mouse ileal loop. Delta-toxin caused fluid accumulation and intestinal permeability to fluorescein isothiocyanate (FITC)-dextran in the mouse ileal loop in a dose- and time-dependent manner. Treatment with delta-toxin induced significant histological damage and shortening of villi. Delta-toxin activates a disintegrin and metalloprotease (ADAM) 10, leading to the cleavage of E-cadherin, the epithelial adherens junction protein, in human intestinal epithelial Caco-2 cells. In this study, E-cadherin immunostaining in mouse intestinal epithelial cells was almost undetectable 1 h after toxin treatment. ADAM10 inhibitor (GI254023X) blocked the toxin-induced fluid accumulation and E-cadherin loss in the mouse ileal loop. Delta-toxin stimulated the shedding of intestinal epithelial cells. The shedding cells showed the accumulation of E-cadherin in intracellular vesicles and the increased expression of active caspase-3. Our findings demonstrate that delta-toxin causes intestinal epithelial cell damage through the loss of E-cadherin cleaved by ADAM10.
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Affiliation(s)
- Soshi Seike
- Laboratory of Molecular Microbiological Science, Faculty of Pharmaceutical Sciences, Hiroshima International University, Kure, Hiroshima 737-0112, Japan.
| | - Masaya Takehara
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
| | - Keiko Kobayashi
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
| | - Masahiro Nagahama
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
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16
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Cheng C, Jiang L, Ma T, Wang H, Han X, Sun J, Yang Y, Chen Z, Yu H, Hang Y, Liu F, Wang B, Fang W, Huang H, Fang C, Cai C, Freitag N, Song H. Carboxyl-Terminal Residues N478 and V479 Required for the Cytolytic Activity of Listeriolysin O Play a Critical Role in Listeria monocytogenes Pathogenicity. Front Immunol 2017; 8:1439. [PMID: 29163512 PMCID: PMC5671954 DOI: 10.3389/fimmu.2017.01439] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 10/17/2017] [Indexed: 11/24/2022] Open
Abstract
Listeria monocytogenes is a facultative intracellular pathogen that secretes the cytolysin listeriolysin O (LLO), which enables the bacteria to cross the phagosomal membrane. L. monocytogenes regulates LLO activity in the phagosome and minimizes its activity in the host cytosol. Mutants that fail to compartmentalize LLO activity are cytotoxic and have attenuated virulence. Here, we showed that residues N478 and V479 of LLO are required for LLO hemolytic activity and bacterial virulence. A single N478A mutation (LLON478A) significantly increased the hemolytic activity of LLO at a neutral pH, while no difference was observed at the optimum acidic pH, compared with wild-type LLO. Conversely, the mutant LLOV479A exhibited lower hemolytic activity at the acidic pH, but not at the neutral pH. The double mutant LLON478AV479A showed a greater decrease in hemolytic activity at both the acidic and neutral pHs. Interestingly, strains producing LLON478A or LLOV479A lysed erythrocytes similarly to the wild-type strain. Surprisingly, bacteria-secreting LLON478AV479A had barely detectable hemolytic activity, but exhibited host cell cytotoxicity, escaped from the phagosome, grew intracellularly, and spread cell-to-cell with the same efficiency as the wild-type strain, but were highly attenuated in virulence in mice. These data demonstrate that these two residues are required for LLO hemolytic activity and pathogenicity in mice, but not for escape from the phagosome and cell-to-cell spreading. The finding that the nearly non-hemolytic LLON478AV479A mutant grew intracellularly indicates that mutagenesis of a virulence determinant is a novel approach for the development of live vaccine strains.
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Affiliation(s)
- Changyong Cheng
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Li Jiang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Tiantian Ma
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Hang Wang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Xiao Han
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Jing Sun
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Yongchun Yang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Zhongwei Chen
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Huifei Yu
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Yi Hang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Fengdan Liu
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Bosen Wang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
| | - Weihuan Fang
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China.,Zhejiang University Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, China
| | - Huarong Huang
- College of Biological and Environmental Science, Institute of Developmental and Regenerative Biology, Hangzhou Normal University, Hangzhou, China
| | - Chun Fang
- College of Animal Science, Yangtze University, Hubei, China
| | - Chang Cai
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China.,School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Nancy Freitag
- Department of Microbiology and Immunology, University of Illinois at Chicago College of Medicine, Chicago, IL, United States
| | - Houhui Song
- College of Animal Science and Technology of Zhejiang A&F University, China-Australian Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Lin'an, China
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17
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Seike S, Takehara M, Takagishi T, Miyamoto K, Kobayashi K, Nagahama M. Delta-toxin from Clostridium perfringens perturbs intestinal epithelial barrier function in Caco-2 cell monolayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:428-433. [PMID: 28988777 DOI: 10.1016/j.bbamem.2017.10.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 09/26/2017] [Accepted: 10/03/2017] [Indexed: 01/02/2023]
Abstract
Clostridium perfringens delta-toxin is a β-barrel-pore-forming toxin (β-PFT) and a presumptive virulence factor of type B and C strains, which are causative organisms of fatal intestinal diseases in animals. We showed previously that delta-toxin causes cytotoxicity via necrosis in sensitive cells. Here, we examined the effect of delta-toxin on intestinal membrane integrity. Delta-toxin led to a reduction in transepithelial electrical resistance (TEER) and increased the permeability of fluorescence isothiocyanate-conjugated dextran in human intestinal epithelial Caco-2 cells without changing the tight junction proteins, such as zonula occludens-1 (ZO-1), occludin, and claudin-1. On the other hand, delta-toxin reduced the cellular levels of adherence junction protein E-cadherin before cell injury. A disintegrin and metalloprotease (ADAM) 10 facilitates E-cadherin cleavage and was identified as the cellular receptor for alpha-toxin, a β-PFT produced by Staphylococcus aureus. ADAM10 inhibitor (GI254023X) blocked the toxin-induced decrease in TEER and cleavage of E-cadherin. Delta-toxin enhanced ADAM10 activity in a dose- and time-dependent manner. Furthermore, delta-toxin colocalized with ADAM10. These results indicated that ADAM10 plays a key role in delta-toxin-induced intestinal injury.
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Affiliation(s)
- Soshi Seike
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Masaya Takehara
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Teruhisa Takagishi
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Kazuaki Miyamoto
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Keiko Kobayashi
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan
| | - Masahiro Nagahama
- Department of Microbiology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
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18
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Abstract
Listeriolysin O (LLO) is a cytolysin capable of forming pores in cholesterol-rich lipid membranes of host cells. It is conveniently suited for engineering a pH-governed responsiveness, due to a pH sensor identified in its structure that was shown before to affect its stability. Here we introduced a new level of control of its hemolytic activity by making a variant with hemolytic activity that was pH-dependent. Based on detailed structural analysis coupled with molecular dynamics and mutational analysis, we found that the bulky side chain of Tyr406 allosterically affects the pH sensor. Molecular dynamics simulation further suggested which other amino acid residues may also allosterically influence the pH-sensor. LLO was engineered to the point where it can, in a pH-regulated manner, perforate artificial and cellular membranes. The single mutant Tyr406Ala bound to membranes and oligomerized similarly to the wild-type LLO, however, the final membrane insertion step was pH-affected by the introduced mutation. We show that the mutant toxin can be activated at the surface of artificial membranes or living cells by a single wash with slightly acidic pH buffer. Y406A mutant has a high potential in development of novel nanobiotechnological applications such as controlled release of substances or as a sensor of environmental pH.
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19
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Briceño MP, Nascimento LAC, Nogueira NP, Barenco PVC, Ferro EAV, Rezende-Oliveira K, Goulart LR, Alves PT, Barbosa BDF, Lima WR, Silva NM. Toxoplasma gondii Infection Promotes Epithelial Barrier Dysfunction of Caco-2 Cells. J Histochem Cytochem 2016; 64:459-69. [PMID: 27370796 DOI: 10.1369/0022155416656349] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 06/01/2016] [Indexed: 12/12/2022] Open
Abstract
After oral infection, Toxoplasma gondii invades intestinal cells, induces breakdown of intestinal physiology and barrier functions, and causes intestinal pathology in some animal species. Although parasites' invasion into host cells is a known phenomenon, the effects of T. gondii infection in the intestinal barrier are still not well established. To evaluate morphological and physiological modifications on the colorectal adenocarcinoma-derived Caco-2 cell line during T. gondii infection, microvilli, tight junction integrity, and transepithelial electrical resistance (TEER) were investigated under infection. It was observed that the dextran uptake (endocytosis) and distribution were smaller in infected than in noninfected Caco-2 cells. The infection leads to the partial loss of microvilli at the cell surface. Claudin-1, zonula occludens-1 (ZO-1), and occludin expressions were colocalized by immunofluorescence and presented discontinuous net patterns in infected cells. Immunoblotting analysis at 24 hr postinfection revealed decreasing expression of occludin and ZO-1 proteins, whereas claudin-1 presented similar expression level compared with noninfected cells. T. gondii decreased TEER in Caco-2 cells 24 hr after infection. Our results suggest that T. gondii infection may lead to the loss of integrity of intestinal mucosa, resulting in impaired barrier function.
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Affiliation(s)
- Marisol Pallete Briceño
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS)
| | | | - Nathalia Pires Nogueira
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS)
| | | | - Eloisa Amália Vieira Ferro
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS),Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil (BFB, EAVF)
| | - Karine Rezende-Oliveira
- Laboratory of Biomedical Sciences, Federal University of Uberlândia, Ituiutaba, Minas Gerais, Brazil (KR-O)
| | - Luiz Ricardo Goulart
- Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil (LRG, PTA)
| | - Patrícia Terra Alves
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS),Laboratory of Nanobiotechnology, Institute of Genetics and Biochemistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil (LRG, PTA)
| | - Bellisa de Freitas Barbosa
- Laboratory of Immunophysiology of Reproduction, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil (BFB, EAVF)
| | - Wânia Rezende Lima
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS),Institute of Exact and Natural Sciences, Federal University of Mato Grosso, Rondonópolis, Mato Grosso, Brazil (WRL)
| | - Neide Maria Silva
- Laboratory of Immunopathology, Institute of Biomedical Sciences (MPB, LACN, NPN, PVCB, WRL, NMS)
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