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De Gaetano GV, Lentini G, Coppolino F, Famà A, Pietrocola G, Beninati C. Engagement of α 3β 1 and α 2β 1 integrins by hypervirulent Streptococcus agalactiae in invasion of polarized enterocytes. Front Microbiol 2024; 15:1367898. [PMID: 38511003 PMCID: PMC10951081 DOI: 10.3389/fmicb.2024.1367898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 02/19/2024] [Indexed: 03/22/2024] Open
Abstract
The gut represents an important site of colonization of the commensal bacterium Streptococcus agalactiae (group B Streptococcus or GBS), which can also behave as a deadly pathogen in neonates and adults. Invasion of the intestinal epithelial barrier is likely a crucial step in the pathogenesis of neonatal infections caused by GBS belonging to clonal complex 17 (CC17). We have previously shown that the prototypical CC17 BM110 strain invades polarized enterocyte-like cells through their lateral surfaces using an endocytic pathway. By analyzing the cellular distribution of putative GBS receptors in human enterocyte-like Caco-2 cells, we find here that the alpha 3 (α3) and alpha 2 (α2) integrin subunits are selectively expressed on lateral enterocyte surfaces at equatorial and parabasal levels along the vertical axis of polarized cells, in an area corresponding to GBS entry sites. The α3β1 and α2β1 integrins were not readily accessible in fully differentiated Caco-2 monolayers but could be exposed to specific antibodies after weakening of intercellular junctions in calcium-free media. Under these conditions, anti-α3β1 and anti-α2β1 antibodies significantly reduced GBS adhesion to and invasion of enterocytes. After endocytosis, α3β1 and α2β1 integrins localized to areas of actin remodeling around GBS containing vacuoles. Taken together, these data indicate that GBS can invade enterocytes by binding to α3β1 and α2β1 integrins on the lateral membrane of polarized enterocytes, resulting in cytoskeletal remodeling and bacterial internalization. Blocking integrins might represent a viable strategy to prevent GBS invasion of gut epithelial tissues.
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Affiliation(s)
| | - Germana Lentini
- Department of Human Pathology, University of Messina, Messina, Italy
| | - Francesco Coppolino
- Department of Biomedical, Dental and Imaging Sciences, University of Messina, Messina, Italy
| | - Agata Famà
- Department of Human Pathology, University of Messina, Messina, Italy
| | - Giampiero Pietrocola
- Department of Molecular Medicine, Biochemistry Section, University of Pavia, Pavia, Italy
| | - Concetta Beninati
- Department of Human Pathology, University of Messina, Messina, Italy
- Scylla Biotech Srl, Messina, Italy
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Treven P, Paveljšek D, Kostanjšek R, Golob M, Bogovič Matijašič B, Mohar Lorbeg P. In vitro model of human mammary gland microbial colonization (MAGIC) demonstrates distinctive cytokine response to imbalanced human milk microbiota. Microbiol Spectr 2024; 12:e0236923. [PMID: 38289112 PMCID: PMC10913382 DOI: 10.1128/spectrum.02369-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 12/19/2023] [Indexed: 03/06/2024] Open
Abstract
Despite the established concept of the human mammary gland (MG) as a habitat with its own microbiota, the exact mechanism of MG colonization is still elusive and a well-characterized in vitro model would reinforce studies of the MG microbiota development. We aimed to establish and characterize an in vitro cell model for studying MAmmary Gland mIcrobial Colonization (MAGIC) model. We used the immortalized cell line MCF10A, which expresses the strong polarized phenotype similar to MG ductal epithelium when cultured on a permeable support (Transwell). We analyzed the surface properties of the MAGIC model by gene expression analysis of E-cadherin, tight junction proteins, and mucins and by scanning electron microscopy. To demonstrate the applicability of the model, we tested the adhesion capability of the whole human milk (HM) microbial community and the cellular response of the model when challenged directly with raw HM samples. MCF10A on permeable supports differentiated and formed a tight barrier, by upregulation of CLDN8, MUC1, MUC4, and MUC20 genes. The surface of the model was covered with mucins and morphologically diverse with at least two cell types and two types of microvilli. Cells in the MAGIC model withstood the challenge with heat-treated HM samples and responded differently to the imbalanced HM microbiota by distinctive cytokine response. The microbial profile of the bacteria adhered on the MAGIC model reflected the microbiological profile of the input HM samples. The well-studied MAGIC model could be useful for studies of bacterial attachment to the MG and for in vitro studies of biofilm formation and microbiota development.IMPORTANCEThe MAGIC model may be particularly useful for studies of bacterial attachment to the surface of the mammary ducts and for in vitro studies of biofilm formation and the development of the human mammary gland (MG) microbiota. The model is also useful for immunological studies of the interaction between bacteria and MG cells. We obtained pioneering information on which of the bacteria present in the raw human milk (HM) were able to attach to the epithelium treated directly with raw HM, as well as on the effects of bacteria on the MG epithelial cells. The MAGIC cell model also offers new opportunities for research in other areas of MG physiology, such as the effects of bioactive milk components on microbial colonization of the MG, mastitis prevention, and studies of probiotic development. Since resident MG bacteria may be an important factor in breast cancer development, the MAGIC in vitro tool also offers new opportunities for cancer research.
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Affiliation(s)
- Primož Treven
- Department of Animal Science, University of Ljubljana, Biotechnical Faculty, Institute of Dairy Science and Probiotics, Domžale, Slovenia
| | - Diana Paveljšek
- Department of Animal Science, University of Ljubljana, Biotechnical Faculty, Institute of Dairy Science and Probiotics, Domžale, Slovenia
| | - Rok Kostanjšek
- Department of Biology, University of Ljubljana, Biotechnical Faculty, Chair of Zoology, Ljubljana, Slovenia
| | - Majda Golob
- University of Ljubljana, Veterinary Faculty, Institute of Microbiology and Parasitology, Ljubljana, Slovenia
| | - Bojana Bogovič Matijašič
- Department of Animal Science, University of Ljubljana, Biotechnical Faculty, Institute of Dairy Science and Probiotics, Domžale, Slovenia
| | - Petra Mohar Lorbeg
- Department of Animal Science, University of Ljubljana, Biotechnical Faculty, Institute of Dairy Science and Probiotics, Domžale, Slovenia
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Miescher I, Rieber J, Schweizer TA, Orlietti M, Tarnutzer A, Andreoni F, Meier Buergisser G, Giovanoli P, Calcagni M, Snedeker JG, Zinkernagel AS, Buschmann J. In Vitro Assessment of Bacterial Adhesion and Biofilm Formation on Novel Bioactive, Biodegradable Electrospun Fiber Meshes Intended to Support Tendon Rupture Repair. ACS Appl Mater Interfaces 2024; 16:6348-6355. [PMID: 38288645 DOI: 10.1021/acsami.3c15710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
The surgical repair of a ruptured tendon faces two major problems: specifically increased fibrous adhesion to the surrounding tissue and inferior mechanical properties of the scar tissue compared to the native tissue. Bacterial attachment to implant materials is an additional problem as it might lead to severe infections and impaired recovery. To counteract adhesion formation, two novel implant materials were fabricated by electrospinning, namely, a random fiber mesh containing hyaluronic acid (HA) and poly(ethylene oxide) (PEO) in a ratio of 1:1 (HA/PEO 1:1) and 1:4 (HA/PEO 1:4), respectively. Electrospun DegraPol (DP) treated with silver nanoparticles (DP-Ag) was developed to counteract the bacterial attachment. The three novel materials were compared to the previously described DP and DP with incorporated insulin-like growth factor-1 (DP-IGF-1), two implant materials that were also designed to improve tendon repair. To test whether the materials are prone to bacterial adhesion and biofilm formation, we assessed 10 strains of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Enterococcus faecalis, known for causing nosocomial infections. Fiber diameter, pore size, and water contact angle, reflecting different degrees of hydrophobicity, were used to characterize all materials. Generally, we observed higher biofilm formation on the more hydrophobic DP as compared to the more hydrophilic DP-IGF-1 and a trend toward reduced biofilm formation for DP treated with silver nanoparticles. For the two HA/PEO implants, a similar biofilm formation was observed. All tested materials were highly prone to bacterial adherence and biofilm formation, pointing toward the need of further material development, including the optimized incorporation of antibacterial agents such as silver nanoparticles or antibiotics.
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Affiliation(s)
- Iris Miescher
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
| | - Julia Rieber
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
| | - Tiziano A Schweizer
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
- Department of Dermatology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Mariano Orlietti
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Andrea Tarnutzer
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Federica Andreoni
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Gabriella Meier Buergisser
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
| | - Pietro Giovanoli
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
| | - Maurizio Calcagni
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
| | - Jess G Snedeker
- Laboratory for Orthopedic Biomechanics, Department of Orthopedics, University of Zurich, Lengghalde 5, 8008 Zurich, Switzerland
| | - Annelies S Zinkernagel
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Rämistrasse 100, 8091 Zurich, Switzerland
| | - Johanna Buschmann
- Division of Plastic Surgery and Hand Surgery, University Hospital Zurich, Sternwartstrasse 14, 8091 Zurich, Switzerland
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Castañeda-Meléndrez AM, Magaña-Lizárraga JA, Martínez-Valenzuela M, Clemente-Soto AF, García-Cervantes PC, Delgado-Vargas F, Bernal-Reynaga R. Genomic characterization of a multidrug-resistant uropathogenic Escherichia coli and evaluation of Echeveria plant extracts as antibacterials. AIMS Microbiol 2024; 10:41-61. [PMID: 38525046 PMCID: PMC10955171 DOI: 10.3934/microbiol.2024003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 03/26/2024] Open
Abstract
Uropathogenic Escherichia coli (UPEC) is the most common bacterial agent associated with urinary tract infections, threatening public health systems with elevated medical costs and high morbidity rates. The successful establishment of the infection is associated with virulence factors encoded in its genome, in addition to antibacterial resistance genes, which could limit the treatment and resolution of the infection. In this sense, plant extracts from the genus Echeveria have traditionally been used to treat diverse infectious diseases. However, little is known about the effects of these extracts on bacteria and their potential mechanisms of action. This study aims to sequence a multidrug-resistant UPEC isolate (UTI-U7) and assess the multilocus sequence typing (MLST), virulence factors, antimicrobial resistance profile, genes, serotype, and plasmid content. Antimicrobial susceptibility profiling was performed using the Kirby-Bauer disk diffusion. The antibacterial and anti-adherent effects of the methanol extracts (ME) of Echeveria (E. craigiana, E. kimnachii, and E. subrigida) against UTI-U7 were determined. The isolate was characterized as an O25:H4-B2-ST2279-CH40 subclone and had resistant determinants to aminoglycosides, β-lactams, fluoroquinolones/quinolones, amphenicols, and tetracyclines, which matched with the antimicrobial resistance profile. The virulence genes identified encode adherence factors, iron uptake, protectins/serum resistance, and toxins. Identified plasmids belonged to the IncF group (IncFIA, IncFIB, and IncFII), alongside several prophage-like elements. After an extensive genome analysis that confirmed the pathogenic status of UTI-U7 isolate, Echeveria extracts were tested to determine their antibacterial effects; as an extract, E. subrigida (MIC, 5 mg/mL) displayed the best inhibitory effect. However, the adherence between UTI-U7 and HeLa cells was unaffected by the ME of the E. subrigida extract.
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Affiliation(s)
| | | | | | | | | | | | - Rodolfo Bernal-Reynaga
- Unidad de Investigaciones en Salud Pública “Dra. Kaethe Willms”, Facultad de Ciencias Químico-Biológicas. Universidad Autónoma de Sinaloa. Ciudad Universitaria, Culiacán, Sinaloa, México
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Yang W, Sun H, Yan J, Kang C, Wu J, Yang B. Enterohemorrhagic Escherichia coli senses microbiota-derived nicotinamide to increase its virulence and colonization in the large intestine. Cell Rep 2023; 42:112638. [PMID: 37294635 DOI: 10.1016/j.celrep.2023.112638] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/05/2023] [Accepted: 05/25/2023] [Indexed: 06/11/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a foodborne pathogen that specifically colonizes and infects the human large intestine. EHEC O157:H7 engages intricate regulatory pathways to detect host intestinal signals and regulate virulence-related gene expression during colonization and infection. However, the overall EHEC O157:H7 virulence regulatory network in the human large intestine remains incompletely understood. Here, we report a complete signal regulatory pathway where the EvgSA two-component system responds to high-nicotinamide levels produced by microbiota in the large intestine and directly activates loci of enterocyte effacement genes to promote EHEC O157:H7 adherence and colonization. This EvgSA-mediated nicotinamide signaling regulatory pathway is conserved and widespread among several other EHEC serotypes. Moreover, disruption of this virulence-regulating pathway by the deletion of evgS or evgA significantly decreased EHEC O157:H7 adherence and colonization in the mouse intestinal tract, indicating that these genes could be potential targets for the development of new therapeutics for EHEC O157:H7 infection.
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Affiliation(s)
- Wen Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China
| | - Hongmin Sun
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China
| | - Jun Yan
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China
| | - Chenbo Kang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China
| | - Junli Wu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, Tianjin 300457, P.R. China; The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Tianjin 300071, P.R. China.
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Harris V, Pifer R, Shannon P, Crary M. Comparative Evaluation of Pseudomonas aeruginosa Adhesion to a Poly-(2-Methacryloyloxyethyl Phosphorylcholine)-Modified Silicone Hydrogel Contact Lens. Vision (Basel) 2023; 7:vision7010027. [PMID: 36977307 PMCID: PMC10056565 DOI: 10.3390/vision7010027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 03/17/2023] [Accepted: 03/19/2023] [Indexed: 03/30/2023] Open
Abstract
Pseudomonas aeruginosa is the most common causative agent associated with microbial keratitis. During contact lens wear, pathogens may be introduced into the ocular environment, which might cause adverse events. Lehfilcon A is a recently developed contact lens with a water gradient surface composed of polymeric 2-methacryloyloxyethyl phosphorylcholine (MPC). MPC is re-ported to impart anti-biofouling properties onto modified substrates. Therefore, in this in vitro experimental study, we tested the capability of lehfilcon A to resist adhesion by P. aeruginosa. Quantitative bacterial adhesion assays using five strains of P. aeruginosa were conducted to compare the adherence properties of lehfilcon A to five currently marketed silicone hydrogel (SiHy) contact lenses (comfilcon A, fanfilcon A, senofilcon A, senofilcon C, and samfilcon A). Compared to lehfilcon A, we observed 26.7 ± 8.8 times (p = 0.0028) more P. aeruginosa binding to comfilcon A, 30.0 ± 10.8 times (p = 0.0038) more binding to fanfilcon A, 18.2 ± 6.2 times (p = 0.0034) more binding to senofilcon A, 13.6 ± 3.9 times (p = 0.0019) more binding to senofilcon C, and 29.5 ± 11.8 times (p = 0.0057) more binding to samfilcon A. These results demonstrate that, for various strains of P. aeruginosa, lehfilcon A reduces bacterial adhesion compared to other contact lens materials.
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Affiliation(s)
| | - Reed Pifer
- Alcon Research, LLC, Fort Worth, TX 76134, USA
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Ismail HS, Azees PAA, Wang H, Ali AI, Mehesen RE, Mahmoud SH, Chen XD, Yeh CK, Garcia-Godoy F. Periodontopathic bacterial adhesion to different restorative materials used to elevate proximal subgingival margins. Eur J Oral Sci 2023; 131:e12909. [PMID: 36526586 DOI: 10.1111/eos.12909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022]
Abstract
This study compared the periodontopathic bacterial adhesion to four restorative materials used for deep margin elevation at 2, 24, and 48-h after incubation. Discs were produced from four restorative materials: resin modified glass ionomer, glass hybrid, flowable bulk fill resin composite, and bioactive ionic resin. Root dentin was used as control. Specimens were coated with saliva and used to culture a biofilm comprised of three strains of periodontopathic bacteria; Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans. Bacterial adherence was assessed by colony count assay, crystal violet staining, and visualized using confocal laser scanning microscopy. Data were analyzed by two-way ANOVA followed by Tukey's post hoc tests. The adhesion values for the control specimens were significantly higher than for other materials, while those for the flowable bulk fill were significantly lower than for any other material within all evaluation assays. The 2-h incubation period showed the lowest adhesion values regardless of the group. The 48-h adhesion values were higher than the 24-h results in all groups except the flowable bulk fill. Microscopic imaging partially supported the findings of the measurements. In terms of periodontopathic bacterial adhesion, the tested flowable bulk fill may be preferable for subgingival use over other tested materials.
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Affiliation(s)
- Hoda S Ismail
- Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.,Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Parveez Ahamed Abdul Azees
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Hanzhou Wang
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Ashraf I Ali
- Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Rabab El Mehesen
- Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Salah H Mahmoud
- Operative Dentistry Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.,Conservative Dentistry Department, Faculty of Dentistry, Horus University, New-Damietta, Damietta, Egypt
| | - Xiao-Dong Chen
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, Texas, USA.,Research Service, South Texas Veterans Health Care System, Audie Murphy VA Medical Center, San Antonio, Texas, USA
| | - Chih-Ko Yeh
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Geriatric Research Education and Clinical Center Audie L. Murphy Division South Texas Veterans Health care system, San Antonio, Texas, USA
| | - Franklin Garcia-Godoy
- Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tennessee, USA.,The Forsyth Institute, Cambridge, Massachusetts, USA
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Duan Q, Pang S, Feng L, Li B, Lv L, Liang Y, Zhu G. Both LTA and LTB Subunits Are Equally Important to Heat-Labile Enterotoxin (LT)-Enhanced Bacterial Adherence. Int J Mol Sci 2023; 24. [PMID: 36674760 DOI: 10.3390/ijms24021245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/04/2023] [Accepted: 01/06/2023] [Indexed: 01/10/2023] Open
Abstract
There is increasing evidence indicating that the production of heat-labile enterotoxin (LT) enhances bacterial adherence within in vitro and in vivo models. However, which subunit plays the main role, and the precise regulatory mechanisms remain unclear. To further elucidate the contribution of the A subunit of LT (LTA) and the B subunit of LT (LTB) in LT-enhanced bacterial adherence, we generated several LT mutants where their ADP-ribosylation activity or GM1 binding ability was impaired and evaluated their abilities to enhance the two LT-deficient E. coli strains (1836-2 and EcNc) adherence. Our results showed that the two LT-deficient strains, expressing either the native LT or LT derivatives, had a significantly greater number of adhesions to host cells than the parent strains. The adherence abilities of strains expressing the LT mutants were significantly reduced compared with the strains expressing the native LT. Moreover, E. coli 1836-2 and EcNc strains when exogenously supplied with cyclic AMP (cAMP) highly up-regulated the adhesion molecules expression and improved their adherence abilities. Ganglioside GM1, the receptor for LTB subunit, is enriched in lipid rafts. The results showed that deletion of cholesterol from cells also significantly decreased the ability of LT to enhance bacterial adherence. Overall, our data indicated that both subunits are equally responsible for LT-enhanced bacterial adherence, the LTA subunit contributes to this process mainly by increasing bacterial adhesion molecules expression, while LTB subunit mainly by mediating the initial interaction with the GM1 receptors of host cells.
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Kwon K, Lee J, Lee S, Ree M, Kim H. Pneumolysin/Plasma Protein Adsorption, Bacterial Adherence, and Cell Adhesion Characteristics of a Cell-Membrane-Mimicking Polymer System. ACS Appl Bio Mater 2022; 5:2240-2252. [PMID: 35436086 DOI: 10.1021/acsabm.2c00111] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This study delivers the first report on a cell-membrane-mimicking polymer system, poly[oxy(4-(13-cholenoatenonyl)-1,2,3-triazoyl-1-methyl)ethylene-random-oxy(4-(13-phosphorylcholinenonyl)-1,2,3-triazoyl-1-methyl)ethylene] (PGA-CholmPCn) films in various compositions in terms of physicochemical properties, protein adsorptions, bacterial adherences, and human cell adhesions. Higher Chol-containing PGA-CholmPCn in a self-assembled multi-bilayer membrane structure is confirmed to show excellently high affinity to pneumolysin (a cytolysin) and its C-terminal fragment (domain 4) but substantially suppressed affinity to the N-terminal fragment (domains 1-3) and further to plasma proteins. Furthermore, the adherences of pathogenic bacteria are increased favorably; however, the adhesion and proliferation of a human HEp-2 cell line are hindered severely. In contrast, higher-PC-containing PGA-CholmPCn membranes promote HEp-2 cell adhesion and proliferation but significantly suppress the adsorptions of pneumolysin and its fragments and plasma proteins as well as bacterial adherence. The results collectively confirm that PGA-CholmPCn can yield a membrane platform enriched with hydrophobic Chol and hydrophilic and zwitterionic PC moieties in any desired compositions, providing highly selective and sensitive physicochemical characters and biocompatibilities which are demanded for applications in various fields including biomedicine, cosmetics, and environmentally friendly consumer products.
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Affiliation(s)
- Kyungho Kwon
- Hanwha Solution/Chemical Research & Development Institute, 76 Gajeong-ro, Yuseong-gu, Daejeon 34128, Republic of Korea
| | - Jongchan Lee
- Analytical Sciences, LG Chem R&D Center, 188 Munji-ro, Yuseong-gu, Daejeon 34122, Republic of Korea
| | - Soomin Lee
- Department of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea
| | - Moonhor Ree
- Surface Technology Institute, Ceko Corporation, 519 Dunchon-daero, Jungwon-gu, Seongnam 13216, Republic of Korea
| | - Heesoo Kim
- Department of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea
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Cozorici D, Măciucă RA, Stancu C, Tihăuan BM, Uță RB, Codrea CI, Matache R, Pop CE, Wolff R, Fendrihan S. Microbial Contamination and Survival Rate on Different Types of Banknotes. Int J Environ Res Public Health 2022; 19:ijerph19074310. [PMID: 35409990 PMCID: PMC8998619 DOI: 10.3390/ijerph19074310] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 12/19/2022]
Abstract
In the COVID-19 pandemic context, numerous concerns have been raised regarding the hygienic status of certain objects we interact with on a daily basis, and especially cash money and their potential to harbor and transmit pathogenic bacteria. Therefore, in the present study, we analyzed different currency bills represented by British pounds (5 £, 10 £ and 20 £), Romanian lei (1 leu, 5 lei and 10 lei), U.S. dollars (1 $, 5 $ and 10 $) and Euros (5 €, 10 € and 20 €) in order to evaluate the bacterial survival rate and bacterial adherence. We used five reference microorganisms by American Type Culture Collection (ATCC, Manassas, VA, USA): Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Enterococcus sp. ATCC 19952, Salmonella enterica subsp. enterica serovar Typhi ATCC 6539, and Listeria monocytogenes ATCC 7644. Microorganisms were selected in accordance with the criteria of prevalence, pathogenicity, opportunism, and incidence. However, Maldi-TOF analysis from samples taken from the banknotes revealed only a few of the common pathogens that are traditionally thought to be found on banknotes. Some of the most important factors for the survival of pathogenic agents on surfaces are the presence of organic matter, temperature and humidity. Our data showed that Salmonella enterica survived 72 h on every banknote tested, while L. monocytogenes tended to improve persistence in humid conditions. Survival rate is also influenced by the substrate composition, being lower for polymer-based banknotes especially for Salmonella enterica, Listeria monocytogenes and Enterococcus sp. The adherence of bacterial strains was lower for polymer-based banknotes British pounds and Romanian Leu, in contrast to the cotton-based U.S dollars and Euro banknotes. The risk of bacterial contamination from the banknote bills is high as indicated by both a strong survival capacity and low adherence of tested bacteria with differences between the two types of materials used for the tested banknotes.
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Affiliation(s)
- Derniza Cozorici
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
- Department of Bioengineering and Biotechnologies, Faculty of Medical Engineering, University Politehnica of Bucharest, 011061 Bucharest, Romania;
| | - Roxana-Alexandra Măciucă
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
- Faculty of Biology, University of Bucharest, 91–95 Splaiul Independenței, 050095 Bucharest, Romania;
| | - Costel Stancu
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
| | - Bianca-Maria Tihăuan
- Research Institute of the University of Bucharest—ICUB, 91-95 Splaiul Independenței, 050567 Bucharest, Romania;
- Research & Development for Advanced Biotechnologies and Medical Devices, SC Sanimed International Impex SRL, 087040 Călugăreni, Romania
| | - Robert Bogdan Uță
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
| | - Cosmin Iulian Codrea
- “Ilie Murgulescu” Institute of Physical Chemistry, Romanian Academy, 202 Splaiul Independentei, 060021 Bucharest, Romania;
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 060042 Bucharest, Romania
| | - Răzvan Matache
- National Institute for Research and Development in Environmental Protection, 294 Splaiul Independentei, 060031 Bucharest, Romania;
| | - Cristian-Emilian Pop
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Bucharest, 91-95 Splaiul Independenței, 050095 Bucharest, Romania
- Correspondence:
| | - Robert Wolff
- College of Nursing and Public Health, South University, 9 Science Ct., Columbia, SC 29203, USA;
| | - Sergiu Fendrihan
- Non-Governmental Research Organization Biologic, 14 Schitului Str., 032044 Bucharest, Romania or (C.S.); (R.B.U.); (S.F.)
- Faculty of Medicine, “Vasile Goldis” University, Revoluției Blvd. 94, 310025 Arad, Romania
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11
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Kim H, Aquino M, Izadjoo M. Development and assessment of a high-throughput biofilm and biomass testing platform. J Wound Care 2021; 30:S36-S46. [PMID: 34256585 DOI: 10.12968/jowc.2021.30.sup7.s36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To develop and evaluate a simple platform technology for developing static biofilms in a 96-well microtitre plate for various downstream applications. The technology allows monitoring of growth rate, biofilm formation and quantifying biofilm biomass by using crystal violet (CV) and safranin O (SO) staining over seven-day time periods for pathogens including clinical isolates most commonly associated with hard-to-treat wound infections. METHOD A total of 157 bacteria including Acinetobacter, Enterobacter, Klebsiella, Pseudomonas and Staphylococcus spp. were used in the study. Bacterial growth was measured at 600nm optical density (OD). Biofilm formation was monitored and assessed quantitatively with CV at 570nm and SO staining at 492nm for one-, two-, three- and seven-day incubation periods. RESULTS Bacterial growth rate and static biofilm biomass in the 96-well plates varied for various strains tested. Both CV and SO staining showed similar results in the biomass, with SO assay displaying more reproducible data throughout the study. Most of the strains were metabolically active even at the seven-day incubation period. Microbial adherences of all bacterial strains on the plastic surface was assessed with CV staining: 28 Acinetobacter, 17 Staphylococcus, 12 Pseudomonas and four Enterobacter strains were strong biofilm producers. Moderate biofilm-producing strains included 27 Staphylococcus, 14 Acinetobacter, eight Pseudomonas and three Enterobacter. Weak biofilm-producing strains included: 33 Staphylococcus, six Enterobacter, two Pseudomonas and one Acinetobacter. Only one Pseudomonas aeruginosa strain did not develop biofilm. CONCLUSION Our results demonstrate the feasibility of using 96-well microtitre plates as a high-throughput platform for quantitative measurement and assessment of biofilm development over time. Studying microbial adherence or biofilm biomass generated on various surfaces using a high-throughput system could provide valuable information for in vitro testing and developing therapeutics for biofilm infections. Employing the biofilm testing platform described in this study makes it possible to simultaneously develop different biofilms formed by specific pathogens, and study potential association between the quantity of bacterial biomass and strength of a biofilm formed by specific wound pathogens. In addition, the described testing approach could provide an optimal model for standardised and high-throughput screening of candidate antibiofilm therapeutics.
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Affiliation(s)
- Hosan Kim
- Integrated Pharma Services, Rockville, MD, US
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12
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Alfouzan AF, Alotiabi HM, Labban N, Al-Otaibi HN, Al Taweel SM, AlShehri HA. Effect of aging and mechanical brushing on surface roughness of 3D printed denture resins: A profilometer and scanning electron microscopy analysis. Technol Health Care 2021; 30:161-173. [PMID: 34250915 DOI: 10.3233/thc-212974] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The use of 3D printed material in the dental field is gaining tremendous attention. However, studies related to 3D printed denture resins are scarce and need consideration before their inclusion in routine clinical practice. OBJECTIVE This study aimed to assess the surface roughness (Ra) of 3D printed denture resins following aging and mechanical brushing. METHODS Forty round samples (diameter, 10 mm and thickness, 3 mm) were fabricated from two 3D printed (DentaBASE and Denture 3D+) and one conventional polymethylmethacrylate (PMMA) denture materials. The samples were thermo-cycled, subjected to mechanical brushing, and later immersed in either artificial saliva (AS), coffee, cola, or lemon juice (n= 10) to simulate one and two years of oral use. Surface roughness (Ra) was determined using a non-contact profilometer and scanning electron microscope was used for qualitative analysis. The data was analyzed using SPSS v.20 (α= 0.05). RESULTS Denture 3D+ demonstrated highest mean Ra (1.15 ± 0.28 μm), followed by PMMA (0.99 ± 0.50 μm) and DentaBASE (0.81 ± 24). The difference in mean Ra between the materials was statistically non-significant (P= 0.08). Amongst the different beverages used, the highest Ra was observed for samples immersed in lemon juice (1.06 ± 0.40 μm) followed by cola (1.04 ± 0.46 μm) and coffee (0.98 ± 0.40 μm), respectively. The lowest Ra was observed for samples immersed in AS (0.85 ± 0.24 μm). CONCLUSION The surface roughness of 3D printed denture resins was comparable with that of conventional PMMA resins. Denture 3D+ demonstrated the highest mean roughness, followed by PMMA and DentaBASE.
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Affiliation(s)
- Afnan F Alfouzan
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Hadeel M Alotiabi
- Dental Intern, College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Nawaf Labban
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Hanan N Al-Otaibi
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Sara Mohammad Al Taweel
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Huda A AlShehri
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
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13
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Jabbar KS, Dolan B, Eklund L, Wising C, Ermund A, Johansson Å, Törnblom H, Simren M, Hansson GC. Association between Brachyspira and irritable bowel syndrome with diarrhoea. Gut 2021; 70:1117-1129. [PMID: 33177165 PMCID: PMC8108289 DOI: 10.1136/gutjnl-2020-321466] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 12/08/2022]
Abstract
OBJECTIVE The incidence of IBS increases following enteric infections, suggesting a causative role for microbial imbalance. However, analyses of faecal microbiota have not demonstrated consistent alterations. Here, we used metaproteomics to investigate potential associations between mucus-resident microbiota and IBS symptoms. DESIGN Mucus samples were prospectively collected from sigmoid colon biopsies from patients with IBS and healthy volunteers, and their microbial protein composition analysed by mass spectrometry. Observations were verified by immunofluorescence, electron microscopy and real-time PCR, further confirmed in a second cohort, and correlated with comprehensive profiling of clinical characteristics and mucosal immune responses. RESULTS Metaproteomic analysis of colon mucus samples identified peptides from potentially pathogenic Brachyspira species in a subset of patients with IBS. Using multiple diagnostic methods, mucosal Brachyspira colonisation was detected in a total of 19/62 (31%) patients with IBS from two prospective cohorts, versus 0/31 healthy volunteers (p<0.001). The prevalence of Brachyspira colonisation in IBS with diarrhoea (IBS-D) was 40% in both cohorts (p=0.02 and p=0.006 vs controls). Brachyspira attachment to the colonocyte apical membrane was observed in 20% of patients with IBS and associated with accelerated oro-anal transit, mild mucosal inflammation, mast cell activation and alterations of molecular pathways linked to bacterial uptake and ion-fluid homeostasis. Metronidazole treatment paradoxically promoted Brachyspira relocation into goblet cell secretory granules-possibly representing a novel bacterial strategy to evade antibiotics. CONCLUSION Mucosal Brachyspira colonisation was significantly more common in IBS and associated with distinctive clinical, histological and molecular characteristics. Our observations suggest a role for Brachyspira in the pathogenesis of IBS, particularly IBS-D.
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Affiliation(s)
- Karolina S Jabbar
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden,Department of Gastroeneterology and Hepatology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Brendan Dolan
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Lisbeth Eklund
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden,Department of Gastroeneterology and Hepatology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Catharina Wising
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Anna Ermund
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Åsa Johansson
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Hans Törnblom
- Department of Gastroeneterology and Hepatology, Sahlgrenska University Hospital, Gothenburg, Sweden,Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Magnus Simren
- Department of Gastroeneterology and Hepatology, Sahlgrenska University Hospital, Gothenburg, Sweden,Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Gunnar C Hansson
- Department of Medical Biochemistry, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
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14
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Zhang F, Dai J, Chen T. Role of Lactobacillus in Female Infertility Via Modulating Sperm Agglutination and Immobilization. Front Cell Infect Microbiol 2021; 10:620529. [PMID: 33569356 PMCID: PMC7868545 DOI: 10.3389/fcimb.2020.620529] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/08/2020] [Indexed: 12/13/2022] Open
Abstract
Infertility has become a common problem in recent decades. The pathogenesis of infertility is variable, but microbiological factors account for a large proportion of it. Dysbiosis of vaginal microbiota is reportedly associated with female infertility, but the influence of normal vaginal microbiota on infertility is unclear. In this review, we summarize the physiological characteristics of the vaginal tract and vaginal microbiota communities. We mainly focus on the bacterial adherence of vaginal Lactobacillus species. Given that the adherent effect plays a crucial role in the colonization of bacteria, we hypothesize that the adherent effect of vaginal Lactobacillus may also influence the fertility of the host. We also analyze the agglutination and immobilization effects of other bacteria, especially Escherichia coli, on ejaculated spermatozoa, and speculate on the possible effects of normal vaginal microbiota on female fertility.
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Affiliation(s)
- Fenghao Zhang
- Institute of Translational Medicine & School of Life Sciences, Nanchang University, Nanchang, China
| | - Jie Dai
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Renal Cancer and Melanoma, Peking University Cancer Hospital and Institute, Beijing, China
| | - Tingtao Chen
- Institute of Translational Medicine & School of Life Sciences, Nanchang University, Nanchang, China
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15
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Short B, Carson S, Devlin AC, Reihill JA, Crilly A, MacKay W, Ramage G, Williams C, Lundy FT, McGarvey LP, Thornbury KD, Martin SL. Non-typeable Haemophilus influenzae chronic colonization in chronic obstructive pulmonary disease (COPD). Crit Rev Microbiol 2021; 47:192-205. [PMID: 33455514 DOI: 10.1080/1040841x.2020.1863330] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Haemophilus influenzae is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and contributes to episodes of acute exacerbation which are associated with increased hospitalization and mortality. Due to the ability of H. influenzae to adhere to host epithelial cells, initial colonization of the lower airways can progress to a persistent infection and biofilm formation. This is characterized by changes in bacterial behaviour such as reduced cellular metabolism and the production of an obstructive extracellular matrix (ECM). Herein we discuss the multiple mechanisms by which H. influenzae contributes to the pathogenesis of COPD. In particular, mechanisms that facilitate bacterial adherence to host airway epithelial cells, biofilm formation, and microbial persistence through immune system evasion and antibiotic tolerance will be discussed.
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Affiliation(s)
- Bryn Short
- University of the West of Scotland, Paisley, United Kingdom
| | - Stephen Carson
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Anna-Claire Devlin
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - James A Reihill
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Anne Crilly
- University of the West of Scotland, Paisley, United Kingdom
| | - William MacKay
- University of the West of Scotland, Paisley, United Kingdom
| | - Gordon Ramage
- Glasgow Biofilm Research Group, Oral Sciences, School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow, United Kingdom
| | - Craig Williams
- University of the West of Scotland, Paisley, United Kingdom
| | - Fionnuala T Lundy
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Lorcan P McGarvey
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Keith D Thornbury
- Smooth Muscle Research Group, Dundalk Institute of Technology, Dundalk, Ireland
| | - S Lorraine Martin
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
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16
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Blumenthal AM, Bou-Akl T, Rossi MD, Wu B, Ren WP, Markel DC. FiberWire vs FiberTape: Comparison of Bacterial Adherence in a Murine Air Pouch Wound Model. Orthop J Sports Med 2021; 8:2325967120964480. [PMID: 33403204 PMCID: PMC7745592 DOI: 10.1177/2325967120964480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 04/20/2020] [Indexed: 11/17/2022] Open
Abstract
Background: For high–tensile strength sutures, past research has largely focused on mechanical properties or bacterial adherence across various manufacturers. Purpose: This study investigated high-tensile strength sutures with different shapes but otherwise identical composition. The purpose was to evaluate the differences between high–tensile strength suture wire and suture tape relative to bacterial adherence and bacterial retention after washout. Study Design: Controlled laboratory study. Methods: Sutures were implanted in dorsal air pouches of 72 BALB/cJ mice. Experimental pouches were inoculated with Staphylococcus aureus; no bacteria were used in the control conditions. The mice were randomized into 3 groups: group 1 underwent suture extraction 7 days after implantation; group 2 underwent an irrigation procedure, followed by immediate suture extraction on day 7; and group 3 underwent an irrigation procedure on day 7, with delayed suture extraction on day 14 after implantation. The sutures were evaluated using confocal microscopy; electron microscopy; and spectrophotometry, through which optical density, as measured by the amount of scattered light, is directly correlated with the number of bacteria. Histological assessment was performed on the pouches. Results: Optical density (mean ± SD) was significantly higher for FiberTape sutures than for FiberWire sutures, respectively, at the 2-hour time point for all groups (group 1, 0.0550 ± 0.0081 vs 0.0162 ± 0.006 [P = .0054]; group 2, 0.0225 ± 0.0049 vs 0.0056 ± 0.0006 [P = .0045]; group 3, 0.055 ± 0.0222 vs 0.0043 ± 0.0005 [P = .0103]). Additionally, groups 2 and 3 showed statistically significant results at the 4-hour time points (group 2, 0.0384 ± 0.0087 vs 0.0145 ± 0.0042 [P = .0280]; group 3, 0.0532 ± 0.0159 vs 0.0101 ± 0.0025 [P = .0058]). The wash fluid also demonstrated significantly greater optical density for the FiberTape than the FiberWire sutures, respectively, at the 2-hour time point for all groups (group 1, 0.1657 ± 0.0319 vs 0.0317 ± 0.008 [P = .0063]; group 2, 0.0522 ± 0.0156 vs 0.0127 ± 0.0022 [P = .0219]; group 3, 0.1707 ± 0.0205 vs 0.0191 ± 0.0053 [P < .0001]). No bacterial growth occurred in the control conditions. Histological assessment revealed only mild inflammation in the control groups as compared with more severe responses in the experimental groups at all time points. Conclusion: FiberTape was associated with increased bacterial adhesion as well as retention as compared with FiberWire in an in vivo murine wound model. Clinical Relevance: This study demonstrates that suture design influences the occurrence of and ability to clear surgical infection and must be considered when selecting high-tensile strength sutures in a clinical setting.
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Affiliation(s)
| | - Therese Bou-Akl
- Ascension Providence Health System, Southfield, Michigan, USA
| | - Mario D Rossi
- Ascension Providence Health System, Southfield, Michigan, USA
| | - Bin Wu
- Ascension Providence Health System, Southfield, Michigan, USA
| | | | - David C Markel
- Ascension Providence Health System, Southfield, Michigan, USA
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17
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Liu Y, Han R, Wang J, Yang P, Wang F, Yang B. Magnesium Sensing Regulates Intestinal Colonization of Enterohemorrhagic Escherichia coli O157:H7. mBio 2020; 11:e02470-20. [PMID: 33173003 DOI: 10.1128/mBio.02470-20] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Sensing specific gut metabolites is an important strategy for inducing crucial virulence programs by enterohemorrhagic Escherichia coli (EHEC) O157:H7 during colonization and infection. Here, we identified a virulence-regulating pathway wherein the PhoQ/PhoP two-component regulatory system signals to the O island 119-encoded low magnesium-induced regulator A (LmiA), which, in turn, activates locus of enterocyte effacement (LEE) genes to promote EHEC O157:H7 adherence in the low-magnesium conditions of the large intestine. This regulatory pathway is widely present in a range of EHEC and enteropathogenic E. coli (EPEC) serotypes. Disruption of this pathway significantly decreased EHEC O157:H7 adherence in the mouse intestinal tract. Moreover, mice fed a magnesium-rich diet showed significantly reduced EHEC O157:H7 adherence in vivo, indicating that magnesium may help in preventing EHEC and EPEC infection in humans. The large intestinal pathogen enterohemorrhagic Escherichia coli (EHEC) O157:H7 detects host cues to regulate virulence gene expression during colonization and infection. However, virulence regulatory mechanisms of EHEC O157:H7 in the human large intestine are not fully understood. Herein, we identified a virulence-regulating pathway where the PhoQ/PhoP two-component regulatory system senses low magnesium levels and signals to the O island 119-encoded Z4267 (LmiA; low magnesium-induced regulator A), directly activating loci of enterocyte effacement genes to promote EHEC O157:H7 adherence in the large intestine. Disruption of this pathway significantly decreased EHEC O157:H7 adherence in the mouse intestinal tract. Moreover, feeding mice a magnesium-rich diet significantly reduced EHEC O157:H7 adherence in vivo. This LmiA-mediated virulence regulatory pathway is also conserved among several EHEC and enteropathogenic E. coli serotypes; therefore, our findings support the use of magnesium as a dietary supplement and provide greater insights into the dietary cues that can prevent enteric infections.
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18
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Carlino MJ, Kralicek SE, Santiago SA, Sitaraman LM, Harrington AT, Hecht GA. Quantitative analysis and virulence phenotypes of atypical enteropathogenic Escherichia coli (EPEC) acquired from diarrheal stool samples from a Midwest US hospital. Gut Microbes 2020; 12:1-21. [PMID: 33131419 PMCID: PMC7644165 DOI: 10.1080/19490976.2020.1824562] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Infectious diarrhea causes approximately 179 million illnesses annually in the US. Multiplex PCR assays for enteric pathogens detect enteropathogenic Escherichia coli (EPEC) in 12-29% of diarrheal stool samples from all age groups in developed nations. The aim of this study was to isolate and characterize EPEC from diarrhea samples identified as EPEC positive by BioFire Gastrointestinal Panel (GIP). EPEC is the second most common GIP-detected pathogen, equally present in sole and mixed infections peaking during summer months. EPEC bacterial load is higher in samples with additional pathogens. EPEC-GIP-positive stool samples were cultured on MacConkey II agar and analyzed by colony PCR for eaeA and bfpA to identify and classify EPEC isolates as typical (tEPEC) or atypical (aEPEC). EPEC were not recovered from the majority of stool samples with only 61 isolates obtained from 277 samples; most were aEPEC from adults. bfpA-mRNA was severely diminished in 3 of 4 bfpA-positive isolates. HeLa and SKCO-15 epithelial cells were infected with EPEC isolates and virulence-associated phenotypes, including adherence pattern, attachment level, pedestal formation, and tight junction disruption, were assessed. All aEPEC adherence patterns were represented with diffuse adherence predominating. Attachment rates of isolates adhering with defined adherence patterns were higher than tEPEC lacking bfpA (ΔbfpA). The majority of isolates formpedestals. All but one isolate initially increases but ultimately decreases transepithelial electrical resistance of SKCO-15 monolayers, similar to ΔbfpA. Most isolates severely disrupt occludin; ZO-1 disruption is variable. Most aEPEC isolates induce more robust virulence-phenotypes in vitro than ΔbfpA, but less than tEPEC-E2348/69.
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Affiliation(s)
- MJ Carlino
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - SE Kralicek
- Department of Medicine, Division of Gastroenterology and Nutrition, Loyola University Chicago, Maywood, IL, USA
| | - SA Santiago
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
| | - LM Sitaraman
- Department of Medicine, Division of Gastroenterology and Nutrition, Loyola University Chicago, Maywood, IL, USA
| | - AT Harrington
- Department of Pathology and Laboratory Medicine, Loyola University Chicago, Maywood, IL, USA
| | - Gail A. Hecht
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA,Department of Medicine, Division of Gastroenterology and Nutrition, Loyola University Chicago, Maywood, IL, USA,Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA,Department of Medical Service, Edward Hines Jr. VA Hospital, Hines, IL,CONTACT Gail A. Hecht Department of Medicine, Division of Gastroenterology, Loyola University Chicago, IL, USA
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19
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Ramos-Vivas J, Chapartegui-González I, Fernández-Martínez M, González-Rico C, Barrett J, Fortún J, Escudero R, Marco F, Linares L, Nieto J, Aranzamendi M, Muñoz P, Valerio M, Aguado JM, Chaves F, Gracia-Ahufinger I, Paez-Vega A, Martínez-Martínez L, Fariñas MC. Adherence to Human Colon Cells by Multidrug Resistant Enterobacterales Strains Isolated From Solid Organ Transplant Recipients With a Focus on Citrobacter freundii. Front Cell Infect Microbiol 2020; 10:447. [PMID: 33042855 PMCID: PMC7525035 DOI: 10.3389/fcimb.2020.00447] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/21/2020] [Indexed: 12/13/2022] Open
Abstract
Enterobacteria species are common causes of hospital-acquired infections, which are associated with high morbidity and mortality rates. Immunocompromised patients such as solid organ transplant (SOT) recipients are especially at risk because they are frequently exposed to antibiotics in the course of their treatments. In this work, we used a collection of 106 Escherichia coli, 78 Klebsiella pneumoniae, 25 Enterobacter spp., and 24 Citrobacter spp. multidrug resistant strains isolated from transplant patients (hepatic, renal or renal/pancreatic) in order to examine their ability to adhere in vitro to HT-29 human colon cells, and to determine if some adhesive characteristics are associated with prevalence and persistence of these strains. A total of 33 E. coli (31%), 21 K. pneumoniae (27%), 7 Enterobacter spp. (28%), and 5 Citrobacter spp. (21%), adhered to the colon epithelial cells. Two main adherence patterns were observed in the four species analyzed, diffuse adherence, and aggregative adherence. Under transmission electronic microscopy (TEM), most bacteria lacked visible fimbria on their surface, despite their strong adherence to epithelial cells. None of the strains studied was able to induce any cytotoxic effect on HT-29 cells although some of them strongly colonizing both cells and glass coverslips at high density. Some of the strains failed to adhere to the epithelial cells but adhered strongly to the cover-slide, which shows that microscopy studies are mandatory to elucidate the adherence of bacteria to epithelial cells in vitro, and that quantitative assays using colony forming unit (CFUs) counting need to be supplemented with pictures to determine definitively if a bacterial strain adheres or not to animal cells in vitro. We report here, for the first time, the aggregative adherence pattern of two multidrug resistant (MDR) Citrobacter freundii strains isolated from human patients; importantly, biofilm formation in Citrobacter is totally dependent on the temperature; strong biofilms were formed at room temperature (RT) but not at 37°C, which can play an important role in the colonization of hospital surfaces. In conclusion, our results show that there is a great variety of adhesion phenotypes in multidrug-resistant strains that colonize transplanted patients.
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Affiliation(s)
| | | | - Marta Fernández-Martínez
- Instituto de Investigación Valdecilla-IDIVAL, Santander, Spain.,Service of Microbiology, Hospital Universitario Marqués de Valdecilla, Santander, Spain
| | - Claudia González-Rico
- Instituto de Investigación Valdecilla-IDIVAL, Santander, Spain.,Service of Infectious Diseases, Hospital Universitario Marqués de Valdecilla, Santander, Spain
| | - John Barrett
- Instituto de Investigación Valdecilla-IDIVAL, Santander, Spain.,New York University School of Medicine, New York, NY, United States
| | - Jesús Fortún
- Infectious Diseases Department, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - Rosa Escudero
- Infectious Diseases Department, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - Francesc Marco
- Service of Microbiology, Hospital Clínic-IDIBAPS, Universidad de Barcelona, Barcelona, Spain
| | - Laura Linares
- Infectious Diseases Service, Hospital Clínic-IDIBAPS, Universidad de Barcelona, Barcelona, Spain
| | - Javier Nieto
- Infectious Diseases Unit, Hospital Universitario de Cruces, Barakaldo, Spain
| | | | - Patricia Muñoz
- Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Maricela Valerio
- Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Jose María Aguado
- Infectious Diseases Unit, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Fernando Chaves
- Service of Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - Irene Gracia-Ahufinger
- Microbiology Unit, Hospital Universitario Reina Sofía, Córdoba, Spain.,Maimonides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,Department of Microbiology, Universidad de Córdoba, Córdoba, Spain
| | - Aurora Paez-Vega
- Infectious Diseases Unit, Hospital Universitario Reina Sofía, Córdoba, Spain
| | - Luis Martínez-Martínez
- Microbiology Unit, Hospital Universitario Reina Sofía, Córdoba, Spain.,Maimonides Biomedical Research Institute of Córdoba (IMIBIC), Córdoba, Spain.,Department of Microbiology, Universidad de Córdoba, Córdoba, Spain
| | - María Carmen Fariñas
- Instituto de Investigación Valdecilla-IDIVAL, Santander, Spain.,Service of Infectious Diseases, Hospital Universitario Marqués de Valdecilla, Santander, Spain
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20
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Biswas BK, Dey S, Chakrabarty A, Laha A, Mandal TK, Karmakar L, Das D. Biocompatible implant mimicking cartilage: A new horizon for reconstructive facial field. Artif Organs 2020; 44:E494-E508. [PMID: 32410232 DOI: 10.1111/aor.13723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/08/2020] [Accepted: 05/05/2020] [Indexed: 11/30/2022]
Abstract
Cartilage is avascular with limited to no regenerative capacity, so its loss could be a challenge for reconstructive surgery. Current treatment options for damaged cartilage are also limited. In this aspect there is a tremendous need to develop an ideal cartilage-mimicking biomaterial that could repair maxillofacial defects. Considering this fact in this study we have prepared twelve silicone-based materials (using Silicone 40, 60, and 80) reinforced with hydroxyapatite, tri-calcium phosphate, and titanium dioxide which itself has proven their efficacy in several studies and able to complement the shortcomings of using silicones. Among the mechanical properties (Young's modulus, tensile strength, percent elongation, and hardness), hardness of Silicone-40 showed similarities with goat ear (P > .05). Silicone peaks have been detected in FTIR. Both AFM morphology and SEM images of the samples confirmed more roughed surfaces. All the materials were nonhemolytic in hemocompatibility tests, but among the twelve materials S2, S3, S5, and S6 showed the least hemolysis. For all tested bacterial strains, adherence was lower on each material than that grown on the plain industrial silicone material which was used as a positive control. S2, S3, S5, and S6 samples were selected as the best based on mechanical characterizations, surface characterizations, in vitro hemocompatibility tests and bacterial adherence activity. So, outcomes of this present study would be promising when developing ideal cartilage-mimicking biocomposites and their emerging applications to treat maxillofacial defects due to cartilage damage.
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Affiliation(s)
- Biswajit Kumar Biswas
- Department of Biomaterial Research, Avinash Institute of Craniofacial & Reconstructive Surgery, Kolkata, India
| | - Sutapa Dey
- Department of Biomaterial Research, Avinash Institute of Craniofacial & Reconstructive Surgery, Kolkata, India
| | - Anindya Chakrabarty
- Department of Biomaterial Research, Avinash Institute of Craniofacial & Reconstructive Surgery, Kolkata, India
| | - Arghya Laha
- Department of Zoology, Barasat Government College, Kolkata, India
| | - Tapan Kumar Mandal
- Department of Pharmacology and Toxicology, West Bengal University of Animal and Fishery Sciences, Kolkata, India
| | - Laxmikanta Karmakar
- Energy Research Unit, School of Material Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Debajyoti Das
- Energy Research Unit, School of Material Sciences, Indian Association for the Cultivation of Science, Kolkata, India
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21
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Martín C, Fernández-Vega I, Suárez JE, Quirós LM. Adherence of Lactobacillus salivarius to HeLa Cells Promotes Changes in the Expression of the Genes Involved in Biosynthesis of Their Ligands. Front Immunol 2020; 10:3019. [PMID: 31998306 PMCID: PMC6962182 DOI: 10.3389/fimmu.2019.03019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/10/2019] [Indexed: 12/11/2022] Open
Abstract
The attachment of a variety of Lactobacilli to the mucosal surfaces is accomplished through the interaction of OppA, a superficial bacterial protein also involved in oligopeptide internalization, and the glycosaminoglycan moiety of the proteoglycans that form the epithelial cell glycocalyx. Upon the interaction of the vaginal isolate Lactobacillus salivarius Lv72 and HeLa cell cultures, the expression of oppA increased more than 50-fold over the following 30 min, with the overexpression enduring, albeit at a lower rate, for up to 24 h. Conversely, transcriptional analysis of 62 genes involved in proteoglycan biosynthesis revealed generalized repression of genes whose products catalyze different steps of the whole pathway. This led to decreases in the superficial concentration of heparan (60%) and chondroitin sulfate (40%), although the molecular masses of these glycosaminoglycans were higher than those of the control cultures. Despite this lowering in the concentration of the receptor, attachment of the Lactobacilli proceeded, and completely overlaid the underlying HeLa cell culture.
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Affiliation(s)
- Carla Martín
- Área de Microbiología, Universidad de Oviedo, Oviedo, Spain.,Instituto Universitario Fernández-Vega, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | - Iván Fernández-Vega
- Instituto Universitario Fernández-Vega, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain.,Hospital Universitario Central de Asturias, Oviedo, Spain
| | - Juan E Suárez
- Área de Microbiología, Universidad de Oviedo, Oviedo, Spain
| | - Luis M Quirós
- Área de Microbiología, Universidad de Oviedo, Oviedo, Spain.,Instituto Universitario Fernández-Vega, Universidad de Oviedo, Oviedo, Spain.,Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
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22
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Martín C, Escobedo S, Pérez-Martínez G, Coll-Marqués JM, Martín R, Suárez JE, Quirós LM. Two alkaline motifs in the Lactobacillus salivarius Lv72 OppA surface are important to its adhesin function. Benef Microbes 2019; 10:101-109. [PMID: 30406694 DOI: 10.3920/bm2018.0052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Glycosaminoglycans are involved in the attachment of Lactobacillus salivarius Lv72, a strain of vaginal origin, to HeLa cell cultures, indicating that they play a fundamental role in the attachment of mutualistic bacteria to the epithelium lining cavities where the normal microbiota thrives. The bacterial OppA protein has been proposed as an adhesin involved in this adherence since, once purified, it significantly interferes with attachment of the lactobacilli to HeLa cell cultures. In this article, the role of OppA is confirmed through the determination of its location at the cell surface and its ability to promote Lactobacillus casei and Lactococcus lactis adherence to eukaryotic cell cultures upon cloning and expression of oppA in these bacteria. The OppA sequence showed five potential domains for glycosaminoglycan-binding, and structural modelling of the protein showed that two of them were located in the vicinity of an OppA superficial groove whose width approached the diameter of the helical form of heparin in solution. Their involvement in the binding was demonstrated through substitution of critical basic amino acids by acidic ones, which resulted in loss of affinity for heparan sulphate and chondroitin sulphate depending on the domain mutated, suggesting that there might be a certain degree of specialisation. In addition, circular dichroism analysis showed that the spectrum changes induced by OppA-heparan sulphate binding were attenuated by the variant proteins, indicating that these motifs are the OppA recognition domains for the eukaryotic cell surface.
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Affiliation(s)
- C Martín
- 1 Área de Microbiología, Universidad de Oviedo, Julián Clavería 6, 33006 Oviedo, Spain.,2 Instituto Universitario Fernández- Vega, Universidad de Oviedo, Av. Doctores Fernández Vega, 34, 33012 Oviedo, Spain
| | - S Escobedo
- 1 Área de Microbiología, Universidad de Oviedo, Julián Clavería 6, 33006 Oviedo, Spain.,3 Instituto Universitario de Biotecnología, Universidad de Oviedo, Doctor Fernando Bongera s/n, 33006 Oviedo, Spain
| | - G Pérez-Martínez
- 4 Laboratorio de Bacterias Lácticas y Probióticos, Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Catedràtic Agustín Escardino Benlloch, 7, 46980 Valencia, Spain
| | - J M Coll-Marqués
- 4 Laboratorio de Bacterias Lácticas y Probióticos, Departamento de Biotecnología, Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Catedràtic Agustín Escardino Benlloch, 7, 46980 Valencia, Spain
| | - R Martín
- 5 National Institute of Agricultural Research, Commensals and Probiotics- Host Interactions Laboratory, Micalis Institute, AgroParisTech, Paris-Sud University, Allée de Vilvert, 78352 Jouy-en- Josas, France
| | - J E Suárez
- 1 Área de Microbiología, Universidad de Oviedo, Julián Clavería 6, 33006 Oviedo, Spain.,3 Instituto Universitario de Biotecnología, Universidad de Oviedo, Doctor Fernando Bongera s/n, 33006 Oviedo, Spain.,6 Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Paseo Río Linares, s/n, 33300 Villaviciosa, Spain
| | - L M Quirós
- 1 Área de Microbiología, Universidad de Oviedo, Julián Clavería 6, 33006 Oviedo, Spain.,2 Instituto Universitario Fernández- Vega, Universidad de Oviedo, Av. Doctores Fernández Vega, 34, 33012 Oviedo, Spain
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23
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Cádiz L, Torres A, Valdés R, Vera G, Gutiérrez D, Levine MM, Montero DA, O'Ryan M, Rasko DA, Stine OC, Vidal R, Del Canto F. Coli Surface Antigen 26 Acts as an Adherence Determinant of Enterotoxigenic Escherichia coli and Is Cross-Recognized by Anti-CS20 Antibodies. Front Microbiol 2018; 9:2463. [PMID: 30459723 PMCID: PMC6232838 DOI: 10.3389/fmicb.2018.02463] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 09/26/2018] [Indexed: 11/13/2022] Open
Abstract
The coli surface antigen 26 (CS26) of enterotoxigenic Escherichia coli (ETEC) had been described as a putative adhesive pilus based on the partial sequence of the crsH gene, detected in isolates from children with diarrhea in Egypt. However, its production and activity as adherence determinant has not been experimentally addressed. The crsH was identified as a homolog of genes encoding structural subunits of ETEC colonization factors (CFs) CS12, CS18, and CS20. These CFs, along with the recently discovered CS30, belong to the γ2 family of pili assembled by the chaperone-usher pathway (CU pili). Further, the complete CS26 locus, crsHBCDEFG, was described in an O141 ETEC strain (ETEC 100664) obtained from a diarrhea case in The Gambia, during the Global Enterics Multicenter Study. Here, we report that CS26 is a pilus of ∼10 nm in diameter, with the capacity to increase the cell adherence of the non-pathogenic strain E. coli DH10B. As for other related pili, production of CS26 seems to be regulated by phase variation. Deletion of crsHBCDEFG in ETEC 100664 significantly decreased its adherence capacity, which was recovered by in trans complementation. Furthermore, CrsH was cross-recognized by polyclonal antibodies directed against the major structural subunit of CS20, CsnA, as determined by Western blotting and immunogold labeling. ETEC CS26+ strains were found to harbor the heat-labile enterotoxin only, within three different sequence types of phylogroups A and B1, the latter suggesting acquisition through independent events of horizontal transfer. Overall, our results demonstrate that CS26 is an adhesive pilus of human ETEC. In addition, cross-reactivity with anti-CsnA antibodies indicate presence of common epitopes in γ2-CFs.
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Affiliation(s)
- Leandro Cádiz
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Alexia Torres
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Raúl Valdés
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Gabriel Vera
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Daniela Gutiérrez
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Myron M Levine
- Center for Vaccine Development and Global Health, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - David A Montero
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Miguel O'Ryan
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - David A Rasko
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - O Colin Stine
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Roberto Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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24
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Palmela C, Chevarin C, Xu Z, Torres J, Sevrin G, Hirten R, Barnich N, Ng SC, Colombel JF. Adherent-invasive Escherichia coli in inflammatory bowel disease. Gut 2018; 67:574-587. [PMID: 29141957 DOI: 10.1136/gutjnl-2017-314903] [Citation(s) in RCA: 297] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/20/2017] [Accepted: 10/28/2017] [Indexed: 02/06/2023]
Abstract
Intestinal microbiome dysbiosis has been consistently described in patients with IBD. In the last decades, Escherichia coli, and the adherent-invasive E coli (AIEC) pathotype in particular, has been implicated in the pathogenesis of IBD. Since the discovery of AIEC, two decades ago, progress has been made in unravelling these bacteria characteristics and its interaction with the gut immune system. The mechanisms of adhesion of AIEC to intestinal epithelial cells (via FimH and cell adhesion molecule 6) and its ability to escape autophagy when inside macrophages are reviewed here. We also explore the existing data on the prevalence of AIEC in patients with Crohn's disease and UC, and the association between the presence of AIEC and disease location, activity and postoperative recurrence. Finally, we highlight potential therapeutic strategies targeting AIEC colonisation of gut mucosa, including the use of phage therapy, bacteriocins and antiadhesive molecules. These strategies may open new avenues for the prevention and treatment of IBD in the future.
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Affiliation(s)
- Carolina Palmela
- Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA.,Division of Gastroenterology, Hospital Beatriz Ângelo, Loures, Portugal
| | - Caroline Chevarin
- Université Clermont Auvergne, Inserm U1071, USC-INRA 2018, M2iSH, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Zhilu Xu
- Department of Medicine and Therapeutics, Institute of Digestive Diseases, LKS Institute of Health Science, State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Hong Kong, China
| | - Joana Torres
- Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA.,Division of Gastroenterology, Hospital Beatriz Ângelo, Loures, Portugal
| | - Gwladys Sevrin
- Université Clermont Auvergne, Inserm U1071, USC-INRA 2018, M2iSH, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Robert Hirten
- Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Nicolas Barnich
- Université Clermont Auvergne, Inserm U1071, USC-INRA 2018, M2iSH, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Siew C Ng
- Department of Medicine and Therapeutics, Institute of Digestive Diseases, LKS Institute of Health Science, State Key Laboratory of Digestive Disease, The Chinese University of Hong Kong, Hong Kong, China
| | - Jean-Frederic Colombel
- Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
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Abstract
Corynebacterium diphtheriae, Corynebacterium pseudotuberculosis and Corynebacterium ulcerans share one distinctive feature: they are all putative carriers of the diphtheria toxin (DT), encoded by a β-corynephage integrated into the genome. Due to its medical relevance, C. diphtheriae may be the most highly investigated species of the genus Corynebacterium. Nevertheless, systemic infections caused by C. ulcerans are increasingly being reported indicating that this species is an emerging pathogen today. C. diphtheriae, C. pseudotuberculosis and C. ulcerans are able to colonize different types of epithelial cells in a strain-specific manner, independent of the presence of the tox gene. However, the molecular mechanisms contributing to host colonization are barely understood. This review gives a comprehensive update of recent data concerning the adhesion properties of toxigenic corynebacteria, demonstrating that adhesion is a multi-factorial process.
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Affiliation(s)
- Lisa Ott
- Friedrich-Alexander-Universität Erlangen-Nürnberg, Professur für Mikrobiologie, Staudtstr. 5, 91058 Erlangen, Germany
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26
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Jain S, Williamson RS, Marquart M, Janorkar AV, Griggs JA, Roach MD. Photofunctionalization of anodized titanium surfaces using UVA or UVC light and its effects against Streptococcus sanguinis. J Biomed Mater Res B Appl Biomater 2017; 106:2284-2294. [PMID: 29098762 DOI: 10.1002/jbm.b.34033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/21/2017] [Accepted: 10/13/2017] [Indexed: 12/22/2022]
Abstract
UV light preirradiation of anodized titanium oxide layers has recently been shown to produce a photocatalytic effect that may reduce early bacterial attachment on titanium surfaces. Streptococcus species have been identified as primary early colonizers and contribute to early biofilm formation on dental implant surfaces. Anodized layers with primarily amorphous, primarily anatase, primarily rutile, and mixtures of anatase and rutile phase oxides were preirradiated with UVA or UVC light for 10 min. Nanoscale surface roughness and pre- and post-UV-irradiated wettability were measured for each anodization group. Sample groups were subjected to streptococcus sanguinis for a period of 24 h. Bacterial attachment and killing efficacy were measured and compared to the corresponding non-UV control groups. UVA treatments showed trends of at least a 20% reduction in bacterial attachment regardless of the crystallinity, or combination of oxide phases present. Anodized layers consisting of primarily anatase phase on the outermost surface were shown to have a killing efficacy of at least 50% after preirradiation with UVA light. Anodized layers containing disperse mixtures of anatase and rutile phases at the outermost surface showed at least a 50% killing efficacy after pre-irradiation with either UVA or UVC light. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2284-2294, 2018.
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Affiliation(s)
- Sakshi Jain
- Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, Mississippi
| | - Randall S Williamson
- Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, Mississippi
| | - Mary Marquart
- Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi
| | - Amol V Janorkar
- Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, Mississippi
| | - Jason A Griggs
- Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, Mississippi
| | - Michael D Roach
- Department of Biomedical Materials Science, University of Mississippi Medical Center, Jackson, Mississippi
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27
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Kern BK, Porsch EA, St Geme JW 3rd. Defining the Mechanical Determinants of Kingella kingae Adherence to Host Cells. J Bacteriol 2017; 199:e00314-17. [PMID: 28874408 DOI: 10.1128/JB.00314-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/23/2017] [Indexed: 12/17/2022] Open
Abstract
Kingella kingae is an important pathogen in young children and initiates infection by colonizing the posterior pharynx. Adherence to pharyngeal epithelial cells is an important first step in the process of colonization. In the present study, we sought to elucidate the interplay of type IV pili (T4P), a trimeric autotransporter adhesin called Knh, and the polysaccharide capsule in K. kingae adherence to host cells. Using adherence assays performed under shear stress, we observed that a strain expressing only Knh was capable of higher levels of adherence than a strain expressing only T4P. Using atomic force microscopy and transmission electron microscopy (TEM), we established that the capsule had a mean depth of 700 nm and that Knh was approximately 110 nm long. Using cationic ferritin capsule staining and thin-section transmission electron microscopy, we found that when bacteria expressing retractile T4P were in close contact with host cells, the capsule was absent at the point of contact between the bacterium and the host cell membrane. In a T4P retraction-deficient mutant, the capsule depth remained intact and adherence levels were markedly reduced. These results support the following model: T4P make initial contact with the host cell and mediate low-strength adherence. T4P retract, pulling the organism closer to the host cell and displacing the capsule, allowing Knh to be exposed and mediate high-strength, tight adherence to the host cell surface. This report provides the first description of the mechanical displacement of capsule enabling intimate bacterial adherence to host cells.IMPORTANCE Adherence to host cells is an important first step in bacterial colonization and pathogenicity. Kingella kingae has three surface factors that are involved in adherence: type IV pili (T4P), a trimeric autotransporter adhesin called Knh, and a polysaccharide capsule. Our results suggest that T4P mediate initial contact and low-strength adherence to host cells. T4P retraction draws the bacterium closer to the host cell and causes the displacement of capsule. This displacement exposes Knh and allows Knh to mediate high-strength adherence to the host cell. This work provides new insight into the interplay of T4P, a nonpilus adhesin, and a capsule and their effects on bacterial adherence to host cells.
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Pérez-Tanoira R, Aarnisalo AA, Eklund KK, Han X, Soininen A, Tiainen VM, Esteban J, Kinnari TJ. Prevention of Biomaterial Infection by Pre-Operative Incubation with Human Cells. Surg Infect (Larchmt) 2017; 18:336-344. [PMID: 28267427 DOI: 10.1089/sur.2016.263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Cells of tissues and biofilm forming bacteria compete for the living space on the surface of an implant. We hypothesized the incubation of the implant (titanium, polydimethylsiloxane, and polystyrene surface) with human cells before implantation as a strategy to prevent bacterial adhesion and biofilm formation. METHODS After 24 hours of incubation with human osteogenic sarcoma SaOS-2 cells (1 × 105 cells/mL), the materials were incubated for 4.5 hours or two days with Staphylococcus aureus in serial 1:10 dilutions of 108 colony-forming units/mL. The bacterial adherence and biofilm biomass on materials pre-incubated with SaOS-2 cells were compared with our previous results on materials incubated only with bacteria or in simultaneous co-culture of SaOS-2 cells and S. aureus. Fluorescent microscopy and crystal violet stain were used. The number of viable SaOS-2 and bacterial cells present was tested using colorimetric methods (MTT, LDH) and drop plate method, respectively. RESULTS The pre-treatment with human cells was associated with a reduction of bacterial colonization of the biomaterial at 4.5 hours and 48 hours compared with the non-pre-treated materials. The presence of bacteria decreased the number of viable human cells on all materials. ( Supplementary Fig. 1 ; see online supplementary materials at www.liebertpub.com/sur ). CONCLUSIONS These results suggest that the pre-operative incubation of prostheses with host cells could prevent infection of biomaterials.
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Affiliation(s)
- Ramón Pérez-Tanoira
- 1 Department of Otorhinolaryngology - Head and Neck Surgery, Helsinki University Hospital and University of Helsinki , Helsinki, Finland
| | - Antti A Aarnisalo
- 1 Department of Otorhinolaryngology - Head and Neck Surgery, Helsinki University Hospital and University of Helsinki , Helsinki, Finland
| | - Kari K Eklund
- 2 Clinicum, University of Helsinki , Helsinki, Finland .,5 Department of Rheumatology, Helsinki University Hospital and University of Helsinki , Helsinki, Finland
| | - Xia Han
- 2 Clinicum, University of Helsinki , Helsinki, Finland
| | - Antti Soininen
- 3 ORTON Research Institute , Helsinki, Finland .,4 ORTON Orthopedic Hospital , Helsinki, Finland
| | - Veli-Matti Tiainen
- 3 ORTON Research Institute , Helsinki, Finland .,4 ORTON Orthopedic Hospital , Helsinki, Finland
| | - Jaime Esteban
- 6 Clinical Microbiology , IIS-Fundación Jiménez Díaz, Madrid, Spain
| | - Teemu J Kinnari
- 1 Department of Otorhinolaryngology - Head and Neck Surgery, Helsinki University Hospital and University of Helsinki , Helsinki, Finland
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29
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Anitua E, Tejero R, Pacha-Olivenza MÁ, Fernández-Calderón MC, Delgado-Rastrollo M, Zalduendo MM, Troya M, Pérez-Giraldo C, González-Martín ML. Balancing microbial and mammalian cell functions on calcium ion-modified implant surfaces. J Biomed Mater Res B Appl Biomater 2017; 106:421-432. [PMID: 28186691 DOI: 10.1002/jbm.b.33860] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/16/2017] [Accepted: 01/26/2017] [Indexed: 12/27/2022]
Abstract
Implant integration is a complex process mediated by the interaction of the implant surface with the surrounding ions, proteins, bacteria, and tissue cells. Although most implants achieve long-term bone-tissue integration, preventing pervasive implant-centered infections demands further advances, particularly in surfaces design. In this work, we analyzed classical microrough implant surfaces (only acid etched, AE; sandblasted then acid etching, SB + AE) and a new calcium-ion-modified implant surface (AE + Ca) in terms of soft- and hard-tissue integration, bacterial adhesion, and biofilm formation. We cultured on the surfaces primary oral cells from gingiva and alveolar bone, and three representative bacterial strains of the oral cavity, emulating oral conditions of natural saliva and blood plasma. With respect to gingiva and bone cells and in the presence of platelets and plasma proteins, AE + Ca surfaces yielded in average 86% higher adhesion, 44% more proliferation, and triggered 246% more synthesis of extracellular matrix biomolecules than AE-unmodified controls. Concomitantly, AE + Ca surfaces regardless of conditioning with saliva and/or blood plasma showed significantly less bacterial adhesion (67% reduction in average) and biofilm formation (40% reduction in average) than unmodified surfaces. These results highlight the importance of a calcium-rich hydrated interface to favor mammalian cell functions over microbial colonization at implant surfaces. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 421-432, 2018.
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Affiliation(s)
- Eduardo Anitua
- Private Practice in Implantology and Oral Rehabilitation, 01007, Vitoria-Gasteiz, Spain.,BTI Biotechnology Institute IMASD, 01510, Miñano, Spain
| | | | - Miguel Ángel Pacha-Olivenza
- Networking Research Centre on Bioengineering, Biomaterial and Biomedicine (CIBER-BBN), Badajoz, Spain.,Department of Applied Physics, Faculty of Science-UEx, 06006, Badajoz, Spain
| | - María Coronada Fernández-Calderón
- Networking Research Centre on Bioengineering, Biomaterial and Biomedicine (CIBER-BBN), Badajoz, Spain.,Department of Biomedical Sciences, Faculty of Medicine-UEx, 06006, Badajoz, Spain
| | - María Delgado-Rastrollo
- Networking Research Centre on Bioengineering, Biomaterial and Biomedicine (CIBER-BBN), Badajoz, Spain.,Department of Biomedical Sciences, Faculty of Medicine-UEx, 06006, Badajoz, Spain
| | | | - María Troya
- BTI Biotechnology Institute IMASD, 01510, Miñano, Spain
| | - Ciro Pérez-Giraldo
- Networking Research Centre on Bioengineering, Biomaterial and Biomedicine (CIBER-BBN), Badajoz, Spain.,Department of Biomedical Sciences, Faculty of Medicine-UEx, 06006, Badajoz, Spain
| | - María Luisa González-Martín
- Networking Research Centre on Bioengineering, Biomaterial and Biomedicine (CIBER-BBN), Badajoz, Spain.,Department of Applied Physics, Faculty of Science-UEx, 06006, Badajoz, Spain
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30
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Mousavi E, Makvandi M, Teimoori A, Ataei A, Ghafari S, Najafian M, Ourang Z, Samarbaf-Zadeh A. In vitro adherence of Lactobacillus strains isolated from the vaginas of healthy Iranian women. J Chin Med Assoc 2016; 79:665-671. [PMID: 27562422 DOI: 10.1016/j.jcma.2016.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/18/2016] [Accepted: 04/20/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The lactobacilli are a part of the bacterial flora of the human vagina. Detection of normal Lactobacillus species in the vaginas of healthy women in different geographical locations, and evaluation of their specific properties, can aid in the selection of the best species for preventing sexually transmitted diseases in the future. This study was performed to isolate and identify the Lactobacillus species in the vaginas of healthy women and to evaluate the adherence of these lactobacilli to Vero and HeLa cell lines. METHODS The study included 100 women. Bacteria were isolated from healthy women and purified. Phenotypic and biochemical tests were performed to identify the lactobacilli. The Lactobacillus species were detected by molecular methods using polymerase chain reaction amplification of the full length of the 16S rDNA of the isolated bacteria. Several isolates of each species were then selected to study their adherence to Vero and HeLa cell lines. RESULTS Among the 50 samples taken from healthy women meeting the inclusion criteria, Lactobacillus species were identified in 33 (66%) samples. Of these lactobacilli, 14 isolates were Lactobacillus crispatus, six (18.2%) were Lactobacillus gasseri, nine (27%) were Lactobacillus rhamnosus, and the rest were either Lactobacillus salivarius (6%) or Lactobacillus plantarum (6%). L. rhamnosus showed the greatest adhesion to the cells when compared to the other tested species. All the lactobacilli isolated in this study showed a smaller capacity for cell adherence when compared with control species. CONCLUSION L. crispatus, L. rhamnosus, and L. gasseri were the dominant Lactobacillus species in the vaginas of healthy women in Iran. L. rhamnosus attached more readily to the cells than did the other species; therefore, this isolate is a good candidate for further studies on the potential health benefits and application of lactobacilli as probiotics.
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Affiliation(s)
- Elham Mousavi
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; Department of Virology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Manoochehr Makvandi
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; Department of Virology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ali Teimoori
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; Department of Virology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Angila Ataei
- Department of Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shokouh Ghafari
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; Department of Virology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mahin Najafian
- Department of Gynecology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ziba Ourang
- Department of Midwifery, Faculty of Nursing and Midwifery, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Alireza Samarbaf-Zadeh
- Health Research Institute, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; Department of Virology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
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31
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Chen R, Cole N, Dutta D, Kumar N, Willcox MDP. Antimicrobial activity of immobilized lactoferrin and lactoferricin. J Biomed Mater Res B Appl Biomater 2016; 105:2612-2617. [PMID: 27758034 DOI: 10.1002/jbm.b.33804] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/02/2016] [Accepted: 10/08/2016] [Indexed: 12/18/2022]
Abstract
Lactoferrin and lactoferricin were immobilized on glass surfaces via two linkers, 4-azidobenzoic acid (ABA) or 4-fluoro-3-nitrophenyl azide (FNA). The resulting surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. The antimicrobial activity of the surfaces was determined using Pseudomonas aeruginosa and Staphylococcus aureus strains by fluorescence microscopy. Lactoferrin and lactoferricin immobilization was confirmed by XPS showing significant increases (p < 0.05) in nitrogen on the glass surface. The immobilization of both proteins slightly increased the overall hydrophobicity of the glass. Both lactoferrin and lactoferricin immobilized on glass significantly (p < 0.05) reduced the numbers of viable bacterial cells adherent to the glass. For P. aeruginosa, the immobilized proteins consistently increased the percentage of dead cells compared to the total cells adherent to the glass surfaces (p < 0.03). Lactoferrin and lactoferricin were successfully immobilized on glass surfaces and showed promising antimicrobial activity against pathogenic bacteria. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2612-2617, 2017.
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Affiliation(s)
- Renxun Chen
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia.,School of Chemistry, University of New South Wales, Sydney, Australia
| | - Nerida Cole
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia.,School of Mathematical and Physical Sciences, University of Technology, Sydney, Australia
| | - Debarun Dutta
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Naresh Kumar
- School of Chemistry, University of New South Wales, Sydney, Australia
| | - Mark D P Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
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32
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Pérez-Tanoira R, Han X, Soininen A, Aarnisalo AA, Tiainen VM, Eklund KK, Esteban J, Kinnari TJ. Competitive colonization of prosthetic surfaces by staphylococcus aureus and human cells. J Biomed Mater Res A 2016; 105:62-72. [PMID: 27513443 DOI: 10.1002/jbm.a.35863] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/26/2016] [Accepted: 08/08/2016] [Indexed: 12/31/2022]
Abstract
Implantation of a biomaterial provides an adhesion substratum both to host cell integration and to contaminating bacteria. We studied simultaneous competitive adhesion of Staphylococcus aureus in serial 1:10 dilutions of 108 colony forming units (CFU)/mL and human osteogenic sarcoma (SaOS-2) or primary osteoblast (hOB) cells, both 1x105 cells/mL, to the surfaces of titanium, polydimethylsiloxane and polystyrene. The bacterial adherence and human cell proliferation, cytotoxicity and production of reactive oxygen species (ROS) were studied using fluorometric (fluorescent microscopy and flow cytometry) and colorimetric methods (MTT, LDH and crystal violet). The bacterial cell viability was also evaluated using the drop plate method. The presence of bacteria resulted in reduced adherence of human cells to the surface of the biomaterials, increased production of ROS, and into increased apoptosis. On the other hand, the presence of either type of human cells was associated with a reduction of bacterial colonization of the biomaterial with Staphylococcus aureus. These results suggest that increasing colonization of the biomaterial surface in vitro by one negatively affects colonization by the other. Host cell integration to an implant surface reduces bacterial contamination, which opens novel opportunities for the design of infection-resistant biomaterials in current implantology and future regenerative medicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 62-72, 2017.
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Affiliation(s)
- Ramón Pérez-Tanoira
- Otorhinolaryngology-Head and Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Xia Han
- Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Antti Soininen
- ORTON Research Institute, Helsinki, Finland.,ORTON Orthopedic Hospital, Helsinki, Finland
| | - Antti A Aarnisalo
- Otorhinolaryngology-Head and Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Veli-Matti Tiainen
- ORTON Research Institute, Helsinki, Finland.,ORTON Orthopedic Hospital, Helsinki, Finland
| | - Kari K Eklund
- Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.,Rheumatology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Jaime Esteban
- Clinical Microbiology, IIS-Fundación Jiménez Díaz, Madrid, Spain
| | - Teemu J Kinnari
- Otorhinolaryngology-Head and Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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33
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Ito K, Saito A, Fujie T, Miyazaki H, Kinoshita M, Saitoh D, Ohtsubo S, Takeoka S. Development of a ubiquitously transferrable silver-nanoparticle-loaded polymer nanosheet as an antimicrobial coating. J Biomed Mater Res B Appl Biomater 2015; 104:585-93. [PMID: 25953203 DOI: 10.1002/jbm.b.33429] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 03/23/2015] [Accepted: 03/30/2015] [Indexed: 01/27/2023]
Abstract
Ultra-thin polymer films (nanosheets) fabricated by a layer-by-layer (LbL) method possess unique properties such as high flexibility, adhesive strength, and transparency, and can be peeled off from a substrate and attached to various surfaces via a water-soluble supporting film. Therefore, flexible and transferrable LbL nanosheets are convenient tools as coating materials. Here, we fabricated a novel antimicrobial coating material by embedding silver nanoparticles (AgNPs) in an LbL nanosheet composed of layers of chitosan and sodium alginate (Ag-LbL nanosheet) by means of a photo-reduction method. Optimizing the amount of irradiated energy applied led to robust antimicrobial efficacy against methicillin-resistant Staphylococcus aureus (MRSA), sufficient to meet ISO standards (ISO 22196), while maintaining the flexibility and adhesive potency of the LbL nanosheet. Thus, the Ag-LbL nanosheet is a promising coating material that can provide antimicrobial efficacy to various surfaces.
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Affiliation(s)
- Keisuke Ito
- Department of Life Science and Medical Bio-Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Akihiro Saito
- Department of Life Science and Medical Bio-Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Toshinori Fujie
- Department of Life Science and Medical Bio-Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Hiromi Miyazaki
- Division of Traumatology, Research institute, National Defense Medical College, Saitama, Japan
| | - Manabu Kinoshita
- Department of Immunology and Microbiology, National Defense Medical College, Saitama, Japan
| | - Daizoh Saitoh
- Division of Traumatology, Research institute, National Defense Medical College, Saitama, Japan
| | - Shinya Ohtsubo
- Project Research Institutes, Comprehensive Research Organization, Waseda University, Tokyo, Japan
| | - Shinji Takeoka
- Department of Life Science and Medical Bio-Science, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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Li N, Ren A, Wang X, Fan X, Zhao Y, Gao GF, Cleary P, Wang B. Influenza viral neuraminidase primes bacterial coinfection through TGF-β-mediated expression of host cell receptors. Proc Natl Acad Sci U S A 2015; 112:238-43. [PMID: 25535343 DOI: 10.1073/pnas.1414422112] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Influenza infection predisposes the host to secondary bacterial pneumonia, which is a major cause of mortality during influenza epidemics. The molecular mechanisms underlying the bacterial coinfection remain elusive. Neuraminidase (NA) of influenza A virus (IAV) enhances bacterial adherence and also activates TGF-β. Because TGF-β can up-regulate host adhesion molecules such as fibronectin and integrins for bacterial binding, we hypothesized that activated TGF-β during IAV infection contributes to secondary bacterial infection by up-regulating these host adhesion molecules. Flow cytometric analyses of a human lung epithelial cell line indicated that the expression of fibronectin and α5 integrin was up-regulated after IAV infection or treatment with recombinant NA and was reversed through the inhibition of TGF-β signaling. IAV-promoted adherence of group A Streptococcus (GAS) and other coinfective pathogens that require fibronectin for binding was prevented significantly by the inhibition of TGF-β. However, IAV did not promote the adherence of Lactococcus lactis unless this bacterium expressed the fibronectin-binding protein of GAS. Mouse experiments showed that IAV infection enhanced GAS colonization in the lungs of wild-type animals but not in the lungs of mice deficient in TGF-β signaling. Taken together, these results reveal a previously unrecognized mechanism: IAV NA enhances the expression of cellular adhesins through the activation of TGF-β, leading to increased bacterial loading in the lungs. Our results suggest that TGF-β and cellular adhesins may be potential pharmaceutical targets for the prevention of coinfection.
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35
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Davidson H, Poon M, Saunders R, Shapiro IM, Hickok NJ, Adams CS. Tetracycline tethered to titanium inhibits colonization by Gram-negative bacteria. J Biomed Mater Res B Appl Biomater 2014; 103:1381-9. [PMID: 25389082 DOI: 10.1002/jbm.b.33310] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 08/14/2014] [Accepted: 10/18/2014] [Indexed: 11/07/2022]
Abstract
As peri-prosthetic infection is one of the most devastating complications associated with implant placement, we have reasoned that such infection can be largely subverted by development of antibacterial implants. Our previous work demonstrated that covalent coupling of vancomycin to titanium alloy prevented colonization by the Gram-positive pathogens, Staphylococcus aureus and Staphylococcus epidermidis. Some orthopedic devices, including permanent prosthesis anchors, and most dental implants are transcutaneous or transmucosal and can be prone to colonization by Gram-negative pathogens. We report here the successful covalent coupling of the broad-spectrum antibiotic, tetracycline (TET), to titanium surfaces (Ti-TET) to retard Gram-negative colonization. Synthetic progress was followed by changes in water contact angle, while the presence of TET was confirmed by immunofluorescence. Ti-TET actively prevented colonization in the presence of bathing Escherichia coli, both by fluorescence microscopy and direct counting. Finally, the Ti-TET surface supported osteoblastic cell adhesion and proliferation over a 72-h period. Thus, this new surface offers a powerful means to protect transcutaneous implants from adhesion of Gram-negative pathogens, decreasing the need for replacement of this hardware.
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Affiliation(s)
- Helen Davidson
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Martin Poon
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ray Saunders
- Department of Biological Science, University of the Sciences, Philadelphia, Pennsylvania
| | - Irving M Shapiro
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Noreen J Hickok
- Department of Orthopaedic Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Christopher S Adams
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, Pennsylvania
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Peyrin-Biroulet L, Gonzalez F, Dubuquoy L, Rousseaux C, Dubuquoy C, Decourcelle C, Saudemont A, Tachon M, Béclin E, Odou MF, Neut C, Colombel JF, Desreumaux P. Mesenteric fat as a source of C reactive protein and as a target for bacterial translocation in Crohn's disease. Gut 2012; 61:78-85. [PMID: 21940721 PMCID: PMC3230831 DOI: 10.1136/gutjnl-2011-300370] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Mesenteric fat hyperplasia is a hallmark of Crohn's disease (CD), and C reactive protein (CRP) is correlated with disease activity. The authors investigated whether mesenteric adipocytes may be a source of CRP in CD and whether inflammatory and bacterial triggers may stimulate its production by adipocytes. DESIGN CRP expression in the mesenteric and subcutaneous fats of patients with CD and the correlation between CRP plasma concentrations and mesenteric messenger RNA (mRNA) levels were assessed. The impact of inflammatory and bacterial challenges on CRP synthesis was tested using an adipocyte cell line. Bacterial translocation to mesenteric fat was studied in experimental models of colitis and ileitis and in patients with CD. RESULTS CRP expression was increased in the mesenteric fat of patients with CD, with mRNA levels being 80 ± 40 (p<0.05) and 140 ± 65 (p=0.04) times higher than in the mesenteric fat of patients with ulcerative colitis and in the subcutaneous fat of the same CD subjects, respectively, and correlated with plasma levels. Escherichia coli (1230 ± 175-fold, p<0.01), lipopolysaccharide (26 ± 0.5-fold, p<0.01), tumour necrosis factor α (15 ± 0.3-fold, p<0.01) and interleukin-6 (10 ± 0.7-fold, p<0.05) increased CRP mRNA levels in adipocyte 3T3-L1 cells. Bacterial translocation to mesenteric fat occurred in 13% and 27% of healthy and CD subjects, respectively, and was increased in experimental colitis and ileitis. Human mesenteric adipocytes constitutively expressed mRNA for TLR2, TLR4, NOD1 and NOD2. CONCLUSION Mesenteric fat is an important source of CRP in CD. CRP production by mesenteric adipocytes may be triggered by local inflammation and bacterial translocation to mesenteric fat, providing a mechanism whereby mesenteric fat hyperplasia may contribute to inflammatory response in CD.
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Affiliation(s)
- Laurent Peyrin-Biroulet
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Florent Gonzalez
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Laurent Dubuquoy
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Christel Rousseaux
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Caroline Dubuquoy
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Cécilia Decourcelle
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Alain Saudemont
- Service de Chirurgie Adultes Ouest, CHU Lille, Lille, France
| | - Mickael Tachon
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France,Laboratoire de Bactériologie Clinique, Faculté de Pharmacie de Lille, Lille, France
| | - Elodie Béclin
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France,Laboratoire de Bactériologie Clinique, Faculté de Pharmacie de Lille, Lille, France
| | - Marie-Françoise Odou
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France,Laboratoire de Bactériologie Clinique, Faculté de Pharmacie de Lille, Lille, France
| | - Christel Neut
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France,Laboratoire de Bactériologie Clinique, Faculté de Pharmacie de Lille, Lille, France
| | - Jean-Frédéric Colombel
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
| | - Pierre Desreumaux
- Universitè Lille Nord de France, Lille, France,Inserm U995, Lille, France,UDSL, Lille, France,Service des Maladies de l'Appareil Digestif et de la Nutrition, CHU Lille, Lille, France
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Letouzey V, Lavigne JP, Garric X, Coudane J, de Tayrac R, Callaghan DO. Is degradable antibiotic coating for synthetic meshes provide protection against experimental animal infection after fascia repair? J Biomed Mater Res B Appl Biomater 2011; 100:471-9. [PMID: 22102417 DOI: 10.1002/jbm.b.31973] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 05/26/2011] [Accepted: 05/31/2011] [Indexed: 01/05/2023]
Abstract
The surgical repair of pelvic organ prolapse using synthetic mesh can fail because of slow or partial implant integration due to poor biocompatibility or infection. As systemic antibiotic prophylaxis has only limited success, we have developed a system that coats standard polypropylene mesh with clinically relevant antibiotics. Amoxicillin and ofloxacin are both released from the mesh in vitro at high levels over 3 days, preventing adhesion and biofilm formation by a clinical isolate of E. coli. In an in vivo incisional hernia repair model in rats, the antibiotic-coated mesh results in appropriate tissue integration with adequate vascularization and collagen formation. When implanted animals are infected with virulent E. coli, both antibiotic coatings provide full protection against infection (as assessed both clinically and microbiologically), thus demonstrating their bioavailability. This method is a specific approach for producing a therapeutic coating that could reduce postsurgical infections.
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Affiliation(s)
- Vincent Letouzey
- Department of Gynecology and Obstetrics, Caremeau University Hospital, Place Pr R Debré, 30000 Nimes, France; Max Mousseron Institute of Biomolecules, UMR CNRS 5247, Universities Montpellier 1 and Montpellier 2, Faculty of Pharmacy, 15 Avenue Charles Flahault, BP 14491, 34093 Montpellier, France.
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Abstract
Bacterial and epithelial cell samples were obtained, within 24 h of onset of pharyngeal symptoms, from the palatine tonsils of nine patients (four female and five male; age range 10-40 years, median age 23) with acute tonsillitis, culture-positive for Streptococcus pyogenes. The specimens were examined using fluorescein isothiocyanate- (FITC) and gold-labelled antiserum to S. pyogenes and fluorescence, scanning electron and transmission electron microscopy. S. pyogenes could be identified both in the mucous layer covering the tonsils and attached to the surface epithelial cells. Long chains of coccus-shaped bacteria could be seen encroaching on the epithelial cell borders. S. pyogenes can apparently penetrate the mucous barrier, attach to the epithelial cells, spread from cell to cell and possibly penetrate into the outermost layer of the epithelial cells. These events in turn provoke cytokine production and/or complement activation, which induce inflammatory reaction in the tonsillar tissue.
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Affiliation(s)
- Markus Lilja
- Departments of Otolaryngology, University of Tromsø, Box 5, Breivika, N-9038 Tromsø, Norway
| | - Simo Räisänen
- Clinical Microbiology, Central Hospital, Kokkola, Finland
| | - Lars-Eric Stenfors
- Departments of Otolaryngology, University of Tromsø, Box 5, Breivika, N-9038 Tromsø, Norway
- Corresponding author. Tel.: +47 776 27390; fax: +47 776 27369; e-mail:
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