Bacterial Adhesion: Biomedical Infections PDF

376-1714-00L Biocompatible Materials Biomaterial associated infections 30.10.2024 Prof. Dr. Katharina Maniura, Empa, Biointerfaces/ D-HEST Dr. Markus Rottmar, Empa, Biointerfaces Prof. Dr. Marcy Zenobi-Wong, ETHZ, D-HEST, Tissue Engineering & Fabrication Bacteria preferentially adhere to (bio)mate...

376-1714-00L Biocompatible Materials Biomaterial associated infections 30.10.2024 Prof. Dr. Katharina Maniura, Empa, Biointerfaces/ D-HEST Dr. Markus Rottmar, Empa, Biointerfaces Prof. Dr. Marcy Zenobi-Wong, ETHZ, D-HEST, Tissue Engineering & Fabrication Bacteria preferentially adhere to (bio)material surfaces infected breast implant: dental plaque Staphylococcus aureus bacterial biofilm hip prosthesis infection: infections of long-term Pseudomonas aeruginosa catheters 2 Biofilms on various (bio)material surfaces animal and human tissues medical devices contact lenses toothbrush ship hull space shuttle pipes Fux et al, Trends Microbiol, 2005, 13(1), 34-40 3 Biomaterials-associated infections  ~70% of nosocomial infections are associated with biomaterials / implants  implant infection rate ≈ 4-5% of all orthopedic and 7% of cardiovascular implants  often, infection leads to revisional surgery => infection resistance is an important biomaterial design criterion In 2050, bacterial infections could lead to Bacteria inside a biofilm are 10 millions deaths per year 1000 times more resistant to antibiotics Deaths attributable to AMR every year « Biofilms are medically important, accounting for over compared to other major causes death 70% of microbial infections in the body » Catheter contaminatio n Gum disease Implant contamination https://amr-review.org Stoodley et al, Nat Rev Microbiol 2004, 2(2), 95-108 4 Current antibiotics: inefficient and counterproductive Spatiotemporal microbial evolution on different concentration of antibiotic 0 1 10 100 1000 100 10 1 0 Baym et al, Science 2016 5 Source: Infectious Diseases Society of America; https://www.idsociety.org/public-health/antimicrobial-resistance/antimicrobial-resistance/ 6 “antibiotics crisis” – a clinically highly relevant issue  declining number of newly approved antibiotics  increasing number of multi-drug resistant bacterial strains => we urgently need new and unconventional ways to fight infections overall and particularly on biomaterials Source: Infectious Diseases Society of America; https://www.idsociety.org/public-health/antimicrobial-resistance/antimicrobial-resistance/ 7 Can Ch take an important lead? Politics/ Pharma: R&D on new antibiotics Science: R&D of alternative concepts (microbiome, bacteriophages, materials..) Teaching objectives  What are the basic principles guiding bacterial adhesion?  You can describe the basics of bacterial catch bonds  Basic understanding why biofilms enhance bacterial resistance  General knowledge about the composition and role of the biofilm matrix  Introduction to bacterial quorum sensing  You know what sterilization methods for biomaterials exist BD Ratner et al., “Biomaterials Science”, 3rd edition, Elsevier 2013 P Ducheyne et al., “Comprehensive Biomaterials”, Elsevier 2011 8 1. Fundamentals of bacterial adhesion  bacteria-substrate interactions  force-enhanced E.coli catch bonds 2. Biofilm formation and quorum sensing  bacterial heterogeneity within biofilms  role of bacterial matrix in developing antimicrobial resistance  quorum sensing under laminar flow  influence of bacterial shape variations on surface colonization  quantification methods of bacterial adhesion and biofilm formation 3. Fighting biomaterial-related infections  antibacterial surfaces  material sterilization 9 Biomaterial-associated infection triangle Moriarty F, et al. Bacterial adhesion and biomaterial surfaces. Comprehensive Biomaterials (2011) section 4.407 10 Bacterial adhesion…  is mostly mediated by non-covalent interactions (electrostatic interactions, hydrogen bonds, van der Waals forces, hydrophobic forces)  occurs via specific / non-specific adhesion  to ligands / ECM proteins within host tissues or adsorbed on biomaterials is often mediated by specific bacterial adhesins (bacterial fimbriae – mannose) Moriarty F, et al. Bacterial adhesion and biomaterial surfaces. Comprehensive Biomaterials (2011) section 4.407 11 The colloidal DLVO theory in microbial adhesion Vtotal = VA + VR repulsive attractive (overlap between (Lifshitz- v.d.Waals) electric double layer) BUT: bacteria are not colloidal particles Hermansson. The DLVO theory in microbial adhesion. Colloids Surf B Biointerfaces vol. 14 (1-4) pp. 105-119 12 Limitations of DLVO theory to explain bacterial adhesion bacteria are not smooth, spherical particles:  they have flagellae and fimbriae which can protrude up to several micrometers from the surface  individual bacteria are covered in hydrophobic pericellular glycocalyx (proteins and polysaccharides)  wide range of species-specific shape variations 500 nm flagella fimbriae / pili Moriarty F, et al. Comprehensive Biomaterials (2011) section 4.407 Young; Microbiol Mol Biol Rev, 2006, 70(3), 660-703 13 Fimbriae and polymer architecture impact E.coli adhesion 500 nm E.coli bacterium Debye length λD: 1 mM: 10 nm; 160 mM: 1 nm  DLVO colloidal theory explains adhesion of non-fimbriated bacteria but fails for the adhesion of fimbriated bacteria -> additional contributions due to hydrophobic interactions of bacterial fimbriae and substrates Pidhatika, Möller, Benetti, Konradi, Rakhmatullina, Muehlebach, Zimmermann, Werner, Vogel, Textor; The role of the interplay between polymer architecture and bacterial surface properties on the microbial adhesion to polyoxazoline-based ultrathin films.; Biomaterials, 2010, vol. 31 (36), 9462-9472 14  Surface roughness  Surface features influence how bacteria interact with a surface Ra is the average roughness of a surface. Rz is the difference between the tallest “peak” and the deepest “valley” in the surface. 15 Summary fundamentals of bacterial adhesion  bacterial adhesion to surfaces is mediated by specific (receptor-ligand) and unspecific interactions  DLVO colloidal theory cannot comprehensively explain bacterial adhesion to (bio)material surfaces as bacteria have a wide variety of shape and surface structures  complex interplay of substrate chemistry and roughness, ionic strength of the medium, and composition of the bacterial envelope controls bacterial adhesion 16 Mechanotransduction – forces co-regulate biological systems cell migration hearing / cilia blood flow Biovisions, Harvard University motor proteins http://cellix.imba.oeaw.ac.at membrane channels Corry and Martinac. Bacterial mechanosensitive channels: Experiment and theory. Biochim Biophys Acta (2008) vol. 1778 pp. 1859-1870 Biovisions, Harvard University 17 Mannose-sensitive E.coli catch bonds surface mannose lectin domain linker pilin 500 nm domain Escherichia coli type 1 FimH - mannose fimbriae medium to high shear switch bacteria LOWER LOWER SHEAR SHEAR (0.5 pN/µm(0.5 2) pN/µmHIGHER 2) HIGHER SHEAR SHEAR (2.2 pN/µm(2.2 2) pN/µm2) Nilsson, Thomas, Trintchina, Vogel, Sokurenko. 2006. J Biol Chem. 281(24):16656-63. Thomas, Nilsson, Forero, Sokurenko, Vogel. 2004. Mol Microbiol 53:1545-57. 18 Slip bonds vs catch bonds energy landscape off rate bond lifetime slip bond catch bond catch bonds demonstrated for E.coli adhesion (FimH) and leukocyte rolling (selectins) Thomas. Mechanochemistry of receptor-ligand bonds. Curr Opin Struct Biol (2009) vol. 19 (1) pp. 50-5 Thomas, Vogel, Sokurenko. Biophysics of Catch Bonds. Annu Rev Biophys (2008) vol. 37 pp. 399-416 19 FimH exists in 2 states with different affinities to mannose flow chamber / SMD simulations NMR structure linker chain extension critical biphasic response to force reversible Thomas, Trintchina, Forero, Vogel, Sokurenko; Cell, 2002, (109), 913-923 substrate-specific binding Thomas, Nilsson, Forero, Sokurenko, Vogel; Mol. Microbiol., 2004, (53(5)), 1545-1557 Le Trong, Aprikian, Kidd, Forero, Tchesnokova, Rajagopal, Rodriguez, Interlandi, Klevit, Vogel, Stenkamp, Sokurenko, Thomas; Cell, 2010, 141(4), 645-655) 20 21 Summary FimH – mannose bacterial catch bonds  the lifetime of conventional slip bonds (e.g. biotin – streptavidin) is drastically reduced as tensile forces are applied  in contrast, catch bonds (e.g. FimH – mannose, selectins) show an increase in bond lifetime of several orders of magnitude  conformational change in the domain-domain interface between the FimH pilin and lectin domain crucial for FimH – mannose catch bonds  the response to force is biphasic and reversible  catch bonds allow bacterial adhesion under non-equilibrium conditions, e.g. under flow (e.g. E.coli cause urinary tract infections!) 22 What are bacterial biofilms?  bacterial biofilms are communities of bacteria of complex 3D architecture growing on abiotic surfaces or host tissues  bacteria embed themselves in a hydrated extracellular matrix (EPS)  bacteria in biofilms are more resistant to environmental stresses such as dehydration, UV light, or antibiotic treatment 23 Biofilm formation Stage 1: Reversible attachment of planktonic cells to the surface Stage 2: Production of a matrix resulting in “irreversible” adhered microcolonies Stage 3: Early development of biofilm architecture Stage 4: Maturation of biofilm architecture Stage 5: Dispersion of single cells from the biofilm Stoodley et al., Annual Review of Microbiology 2002 24 Persistence of medical biofilms  (a) Planktonic bacteria are killed by antibiotics and immune system  (b) Planktonic bacteria adhere and form a biofilm on inert surface  (c) The biofilm matrix is protecting bacteria from antibiotics and phagocytes  (d) Phagocytosis is frustrated but phagocytic enzymes are still released and damage host tissues Costerton et al., Science 1999 25 Human infections involving biofilms 26 Bacterial biofilms are characterized by heterogeneity Flemming et al, Nat Rev Microbiol 2016, 14(9), 563-575 27 Bacterial co-aggregation leading to multi-species biofilms Rickard et al., Trends in Microbiology 2003 28  Biofilms as bacterial fortress to resist antimicrobials Flemming et al, Nat Rev Microbiol 2016, 14(9), 563-575  increased ability of bacteria within biofilms to survive exposure to antimicrobial agents  diffusion-reaction inhibition results in sublethal antimicrobial concentration that leads to the development of resistant bacteria 29  The biofilm matrix - the perfect slime  bacteria-produced biofilm matrix comprised of hydrated extracellular polymeric substances (EPS)  mainly polysaccharides (e.g. alginate), proteins, nucleic acids and lipids  interconnected 3D polymer network / hydrogel  physical and chemical protection adapted from: Flemming; Wingender, Nat Rev Microbiol 2010, 8(9), 623-633 30 Immune evasion mechanisms employed by biofilm  frustrated phagocytosis induced by the matrix acting as a physical barrier  downregulation of pathogen-associated molecular patterns during biofilm development to inhibit immune recognition  production of toxins targeting macrophages enhanced by quorum sensing  immune polarization to induce a non- inflammatory response Leid, Microbe 2009 31 Quorum sensing – bacterial small talk in bacterial colonies  bacteria in biofilm communities "talk" to each other through secreted chemical signals  removing this communication prevents bacteria within the biofilm from forming complex, heterogeneous structures  threshold-controlled communication informs bacteria e.g. when there are sufficient numbers of their community => density-dependent modulation of gene-expression 32  Quantification of bacterial adhesion and biofilm formation Moriarty, T.F., Poulsson, A.H.C., Rochford, E.T.J., Richards, R.G. Bacterial Adhesion and Biomaterial Surfaces. Comprehensive Biomaterials (2011) section 4.407 total bacteria count viable bacteria total biomass  Acridine Orange  BacTiter-Glo  Crystal Violet  Syto9  turbidity threshold  Safranin Red  Live/Dead staining Stiefel P et al. Appl Microbiol Biotechnol, 2016. 100(9): p. 4135-45. 33 Quantification of bacterial viability  plating / colony counting methods  selective membrane (im-)permeable fluorescent DNA stains to probe bacterial membrane integrity / viability (e.g. microscopy, FACS) Avalos Vizcarra, Emge, Miermeister, Chabria, Konradi, Vogel, Moeller; Biointerphases, 2013, 8(1), 1-9 34 Where do we need to protect from biofilms after trauma? bone penetration biofilm on implant bacteria on bone fragments trauma wounds and repaired fractures are complex wounds with highly variable features and dimensions slide provided by F. Moriarty, AO Foundation, Davos 35 Fighting biomaterial-related infections - protect the device from infection at the time of implantation and beyond 36 Adhesion-resistant surface modifications  polymer brushes (e.g. PLL-g-PEG)  SAMs with end group that renders surface inert (e.g. oligo-ethylene glycol, mannitol, maltose, taurin, …)  biomimetic or bioinspired approaches (nanotexture, furanone) POLYMER BRUSH WITH POLYMER BRUSH WITH NEG. CHARGE POS. CHARGE 37 Lessons from nature: antifouling, nano-structured cicada wings 5μm 1μm 2μm 200nm Ivanova et al. Small 2012, 8:2489–2494 38 In vitro methods for the evaluation of antimicrobial surfaces Sjollema, Jelmer, Zaat, et al; Acta Biomaterialia, 2018, 70, 12-24 39 Industrial standard evaluation tests of antimicrobial surfaces Sjollema, Jelmer, Zaat, et al; Acta Biomaterialia, 2018, 70, 12-24 40 Sterilization of biomaterials  biomaterials enter sterile body tissues during surgery  sterilization denotes the complete elimination of all forms of microbial life  assessed by sterility assurance level (SAL; describes the probability of a single product being unsterile; SAL typically between 10-3 to 10-6)  physical and chemical methods commonly used to inactivate microbial life-forms 41 Sterilization methods  physical: heat, pressure, filtration, ionizing radiation  chemical: gas / liquid sterilants (e.g. ethylene oxide, gas plasma) Qiu, Q, Sun, W., Connor, J. Sterilization of Biomaterials of Synthetic and Biological Origin. Comprehensive Biomaterials (2011) section 4.410 42 Summary  Bacterial adhesion to surfaces is mediated by specific and unspecific interactions and depends on surface properties  mechanical forces reduce the lifetime of slip bonds, but increase the lifetime of catch bonds => shear- enhanced adhesion  biofilms allow bacteria to “hide” from antibacterial factors and shear flow, and enable cell-cell communication  in vitro methods to quantify bacterial adhesion and viability  overview of physical and chemical sterilization methods  antibacterial strategies of engineered surfaces 43 Outlook Jeferson, FEMS Microbiol Lett 2004, 236, 163-73 Grainger; Nat Biotechnol, 2013, (31(6)), 507-509 - Implant/biomaterial-related infection problem persists even though numerous antifouling surfaces have been developed - If interfering with bacterial adhesion is not sufficient, what else can we target to reduce biofilm formation? - ongoing research in the field to design strategies to modulate the cells of the host immune system 44 Outlook 2 https://doi.org/10.3390/antibiotics8030138 https://doi.org/10.1016/j.jff.2020.104080 45