GAef Pre EAC Workshop Prague September 1, Institut für Anatomie

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1 GAef Pre EAC Workshop Prague September 1, 2013 STATE OF THE ART EXPERIMENTAL CONCEPTS TO ADDRESS HEALTH EFFECTS AND TOXICOLOGY OF COMBUSTION AEROSOLS Peter Gehr Professor emeritus University of Bern Bern Switzerland

2 LUNG FUNCTION (FEV1) OF ASTHMATICS DECREASED SIGNIFICANTLY WHILE WALKING ALONG THE DIESEL BUS ROUTE (OXFORD STREET) % change in FEV p < Hyde Park Oxford Street McCreanor et al, NEJM 2007 Hours (from start of exposure) Picture from Nino Künzli Swiss Tropical and Public Health Institute Basel, Switzerland

3 CONCENTRATION OF PARTICLES AND HEALTH DISTANCE FROM BUSY ROAD Relative Concentration 100 % 80 % Concentration of particles Fine PM, homogenously distributed Ultrafine PM and other primary toxicants strong dependance on distance from source 60 % HWY Relative m concentrations of fine particulates and ultrafines în relation to distance from highway Los Angeles (at curbside = 100%) Zhu et al, J Air Waste Manage Assoc, 2002; 52: 1032 Adjusted prevalence [%] Health Wheezing with breathing problems Wheezing w/o colds Chronic cough Chronic cough or phlegm Residential distance from highway [m] Pictures from Nino Künzli Swiss Tropical and Public Health Institute Basel, Switzerland

4 PORTALS OF ENTRY FOR PARTICLES Lung (inhalation) Main portal of entry Lung parenchyma Surface 140 m 2 Air blood barrier < 1 m 50 m GI Tract (ingestion) Small intestine Surface 200 m 2 Intestine blood barrier m 50 m Skin (dermal application) (Blood vessels (injection)) Skin Surface 2 m 2 Skin blood barrier m 50 m Leonardo da Vinci, Anatomical atlas, above trachea: dust is harmful Oberdörster et al. Environ Health Perspect 2005 ppt from Barbara Rothen Rutishauser, 2010 Blood vessels Surface m² Blood vessel tissue barrier m 50 m

5 LUNG MORPHOLOGY (Human Lung) Gehr et al., Respir. Physiol., 1978 Ewald R. Weibel, Bern

6 DID YOU KNOW THIS ABOUT THE HUMAN LUNG? Tennis field 450 Mill. alveoli (M. Ochs, Univ. of Bern) with a surface area of 140 m 2 (diameter ¼ mm, gasexchange region 80-90%) E.R. Weibel, Universität Bern Red wine glass Volume of capillary blood involved in gas exchange: 210cm 3 (B. Rothen-Rutishauser, Universität Bern) 1/50 of the thickness of a women s hair Thickness of tissue barrier: <1 m Gehr et al., Respir. Physiol., 1978

7 HEALTHY/«CLEAN» LUNG AND POLLUTED LUNG Boehringer Ingelheim Boehringer Ingelheim Burkhardt, Pathology, University of Bern

8 PARTICLE DEPOSITION IN THE LUNG Preferential deposition of particles and nanoparticles P. Straehl, BAFU, Abt. Luft-reinhaltung und NIS Place Upper Airways Trachea Bronchi Bronchioles Alveoli P Particle size <1 m (incl. nanoparticles) The smaller the particles the deeper they penetrate into the lung: (1) There, nanoparticles may penetrate into tissue and cells (organelles, nucleus). (2) There, nanoparticles may translocate into the cappillary blood. (3) By the blood circulation, nanoparticles are transported to other organs.

9 THE FILTER CONCEPT THE AIRWAY TREE AS A PARTICLE FILTER INCLUDING SELF CLEANING SYSTEM (MUCOCILIARY ACTIVITY) Trachea Airway wall Liquid layer Cilia W. Weber, University of Bern

10 STRUCTURE AND DISPLACEMENT (FILTER FUNCTION: SURFACTANT) Flüssigkeitsfilm (+Surfactant) Zilien S. Schürch, S. Tschanz, Univ. Bern Zilien Flüssigkeitsfilm Surfactant Gehr et al., J. Aerosol Med., 1990 Schürch et al., Respir. Physiol., 1990 Gehr et al., J. Aerosol Med., 1996

11 PARTICLE DISPLACEMENT (FILTER FUNCTION: SURFACTANT) Airways 3 µm Alveoli 1 µm A Air Phase (Water Vapor) Gehr et al., J. Aerosol Med., 1990 Schürch et al., Respir. Physiol., 1990 r r R Aqueous Phase 2 r R B r R R C F F R D Cell Layer

12 TRANSLOCATION FROM AIR INTO BLOOD 1 m E.R. Weibel, University of Bern 0.1 m (and smaller)

13 TRANSLOCATION WITH BLOOD TO OTHER ORGANS Nanoparticles Brain Nose Lung Skin GI-Tract Blood Brain Bone Marrow Spleen Wall Blood Vessels Liver Heart Placenta Fetus Degenerative Changes

14 TRANSLOCATION AMOUNT OF NANOPARTICLES IN OTHER ORGANS Intratracheal instillation in WKY rats 1-10 µg 198 Au particles in 50 µl saline, negative ionic surface charge # of particles: (1.4 nm cluster) (18 nm colloid) G. Schmid, Univ. of Essen, Germany Mass fractions of gold nanoparticles in different organs after 24 h lung instillation 1.5nm cluster 18nm colloid 1.E+00 lung instillation 1.5nm cluster 18nm colloid Courtesy: W.G. Kreyling (Helmholtz Center Munich) 24-h retention 24-h retention 1,E+00 1.E-01 1,E-01 1.E-02 1,E-02 1.E-03 1,E-03 1,E-04 1.E-04 1,E-05 1.E-05 1,E-06 1.E-06 lungs lungs GIT+feces GIT+feces lungs GIT+feces liver liver spleen spleen liver kidney kidney spleen blood blood kidney urine urine blood brain brain urine brain Semmler-Behnke et al., Small, 2008 Focus Network Nanoparticles and Health HelmholtzZentrum münchen

15 WHAT HAS TO BE CONSIDERED OF NANOPARTICLES FROM COMBUSTION AEROSOLS Size of particles (nanoparticles) Displacement of nanoparticles towards epithelial layer (surfactant, surface forces) Distance to capillaries (translocation) Distance to sensitive cells (interaction), effect: immune modulation?) Interaction with cells (uptake/penetration, effect: immune modulation, oxidative stress, inflammatory reaction a.o.?)

16 MAIN ACTORS ARE CELLS: EPITHELIAL CELLS, MACROPHAGES, DENDRITIC CELLS Nat. Geogr., ~2000 Nat. Geogr., ~2000

17 DO THEY COLLABORATE? THE CELL MODEL TO TEST THIS: THE TRIPLE CELL CO-CULTURE MODEL Surfactant Macrophage Basal Lamina Dendritic Cell Epithelial Cell Epithelial cell monolayer (A549 or 16HBE cells) Macrophage Epithelial Cells Monolayer Macrophage Dendritic cell Rothen-Rutishauser et al., Am. J. Respir Cell Mol. Biol. 32: , 2005 Rothen-Rutishauser et al., Expert. Opin. Drug Metab. Toxicol. 4: , 2008 Membrane Dendritic Cells

18 INTERPLAY OF MAKROPHAGES AND DENDRITIC CELLS Blank et al., AJRCMB 36: , 2007 Deconvolution technique IMARIS 3D&4D Image Analysis Software Bitplane AG, Scientific Software

19 CELL-CELL INTERACTIONS THE CELLS DO COLLABORATE! Blank et al., Am. J. Respir. Cell Molec. Biol., 2007

20 RELATIVE DISTRIBUTION INDEX DISTRIBUTION RELATIVE TO SIZE OF STRUCTUR Observed and expected numbers of particles taken up by the three different cell types Number of particles * Black: expected White: observed * * * 1000nm 200nm 78nm Particle size * Χ 2 = 35.2 P < AM Ep DC AM Ep DC AM Ep DC * Ch. Mühlfeld, In: Rothen-Rutishauser et.al., Part. Fibre Toxicol., 2007

21 A BURNING QUESTION: HOW DO NANOPARTICLES ENTER CELLS? X ( A: Phagocytosis) B: Macropinocytosis C: Clathrin-mediated endocytosis D: Clathrin and caveolae independent endocytic pathways E: Caveolae-mediated endocytosis F: Adhesive interaction (entering): interaction of nanoparticles with cell membrane, effect on fluidity, nanoparticles may slip into cell between phospholipid molecules ( U. Nienhaus, KIT) Brandenberger et al., Small, 2010

22 AND AN ANSWER: ELECTROCHEMISTRY AND SURFACE-ENHANCED INFRARED ABSORPTION SPECTROSCOPY ON MODEL MEMBRANES (DAP-QDs) Lipid composition of the inner or outer RBC membrane leaflets 1-Dodecanethiol (DT) DT DT + lipid (outer) DT + lipid + DPA-QDs Electrochemistry: voltammograms indicate that lipid layers do not conduct current upon DPA-QD exposure no holes formed! Courtesy: G.U. Nienhaus, Institute of Applied Physics, KIT Wang et al., ACS Nano 6 (2012) IR beam SEIRAS: Membrane flexibility is enhanced in the presence of DPA-QDs DT + lipid (inner) DT + lipid + DPA-QDs (Rothen-Rutishauser et al., Environ. Sci. Technol., 2006) (Rothen-Rutishauser et al., In Donaldson and Borm,Taylor&Francis, 2007)

23 INTRACELLULAR COMPARTMENTS WITH PLAIN AND PEG-COATED GOLD NPs Membrane bound (in vesicles/lysosomes) Plain Au nanoparticles Free (in cytosol) Brandenberger et al., Small, 2010 (in press) PEG coated Au nanoparticles more nanoparticles in cytosol

24 ENTERING AND TRAFFICKING RELATIVE DEPOSITION INDEX, RDI RDI=1 Conclusions: - More nanoparticles in vesicles (lysosomes) - More PEG coated nanoparticles in cytosol RDI=1 Brandenberger et al., Small, 2010

25 WHAT WE SHOULD CONSIDER WHEN WORKING WITH NANOPARTICLES risk = f(hazard, exposure) for a given size effect = f(dose, time) for a given size Interaction of nanoparticles with biological systems is primarily a function of size (size matters): peneatration, translocation, effect/reaction Important are furthermore: material, corona, agglomeration, time etc.

26 EFFECTS OF DIESEL EXHAUST ON BIOLOGICAL SYSTEMS Exposure system Opel Astra X20DTL, 35 km/h Exhaust system Fuel: low sulfur diesel (>10mg/kg, Greenergy SA) Lube oil (V10.237, Motorex) Exhaust dilution 1:10 Müller et al. Environ Sci Technol 2009; Steiner et al. Tox Letters 2012 in press Without particle filter With a silicon carbide diesel particle filter Courtesy: Barbara Rothen-Rutishauser Adolphe Merkle Institute University of Fribourg Switzerland Filter von Peugeot, Filterhersteller Ibiden

27 DIESEL EXHAUST: PARTICLE SIZE DISTRIBUTION 1.00E E+07 counts dn/dlog Dp [1/cm3] 1.00E E E E E E E d [nm] Courtesy: Barbara Rothen-Rutishauser Steiner et al. 2012, in press Adolphe Merkle Institute University of Fribourg Switzerland 0.5 m Without Filter With diesel particle filters

28 DIESEL EXHAUST: INFLAMMATORY REACTION * TNF Sekretion, an inflammatory cytokine * Reference Exhaust Without filter With diesel particle filter 0.4 Confocal light micrograph (blue: nuclei, red: actin) Standard Roh-Abgas DPF 2h LPS Standard Roh-Abgas DPF 6h LPS Courtesy: Barbara Rothen-Rutishauser Adolphe Merkle Institute University of Fribourg Switzerland n=3 6 Steiner et al. 2012, in press

29 LUNG FUNCTION OF CHILDREN OF MOTHERS EX- POSED TO AIR POLLUTION DURING PREGNANCY: DISTANCE TO SOURCE (ROAD, TRAFFIC) What do the results mean? IQR (25 th -75 th percentile) Increase in PM 10 is associated with an increase in respiratory rate of 6.4/min (mean 44/min). Mean (IQR) Bern: 22 (20-24) μg/m 3 Mean (IQR) Mexico-City: 68 (56-92) μg/m 3 Work from Urs Frey and Philipp Latzin Chlidren s Hospital University of Bern Latzin et al., Eur. Respir. J. 33: , 2009

30 SUMMARY COMBUSTION AEROSOLS HAVE EFFECTS ON LUNG FUNCTION (PARTICLE LUNG INTERACTION) Deposition on internal surfaces of the lungs Displacement of particles towards epithelial layer by surfactant at air aqueous phase interface (surface forces) Interaction with pulmonary cells (epithelial, defence system): cellular interplay, intracellular trafficking Translocation through air blood tissue barrier into capillary blood Tanslocation to secondary organs by blood circulation

31 TAKE HOME MESSAGE COMBUSTION AEROSOLS Diesel exhaust is carcinogenic (International Agency for Research on Cancer, IARC; WHO, June 2012) Filters contribute substantially to the reduction of adverse effects from diesel exhaust Distance to source of air pollution (e.g. traffic) is crucial Effects on lungs: Reduced pulmonary function in adults exposed to air pollution (1 st slide) Reduced development and function of lungs in neonates of mothers who lived close to air pollution source (e.g. busy road) during pregnancy (last slide)

32 ACKNOWLEDGEMENTS University of Bern Barbara Rothen-Rutishauser Today: Universities of Fribourg/Bern Martin Clift Today: University of Fribourg Fabian Blank Christina Brandenberger Today: University of Michigan Loretta Müller Today: University of North Carolina Andrea Lehmann Today: RMS Foundation R. Mathys Michael Gasser Today: Fed. Dpt. Home Affairs David Raemy Today: Insel Hospital Univ. of Bern Marc Wehrli Oliver Baum Sandra Frank Andrea Stokes Barbara Tschirren University of Giessen, Germany Christian Mühlfeld Today: Medizinische Hochschule Hannover, Germany University of Calgary, Canada Samuel Schürch Collaboration with: ETH: Zurich EMPA: St.Gallen IST: Lausanne Helmholtz Zentrum: München Universität Ulm: Ulm Universität Marburg: Marburg Heriot-Watt University: Edinburgh Sponsoring