2004 Progress Report: Ultrafine Particle Cell Interactions: Molecular Mechanisms Leading to Altered Gene Expression
EPA Grant Number: R827354C005Subproject: this is subproject number 005 , established and managed by the Center Director under grant R827354
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Airborne PM - Rochester PM Center
Center Director: Oberdorster, Gunter
Title: Ultrafine Particle Cell Interactions: Molecular Mechanisms Leading to Altered Gene Expression
Investigators: Finkelstein, Jacob N. , Gelein, Robert , O'Reilly, Michael , Oberdörster, Günter , Phipps, Richard
Current Investigators: Finkelstein, Jacob N.
Institution: University of Rochester
EPA Project Officer: Stacey Katz/Gail Robarge,
Project Period: June 1, 1999 through May 31, 2005 (Extended to May 31, 2006)
Project Period Covered by this Report: June 1, 2004 through May 31, 2005
RFA: Airborne Particulate Matter (PM) Centers (1999)
Research Category: Particulate Matter
Description:
Objective:The experiments performed within this project are designed to address specific mechanistic hypotheses regarding the interactions between inhaled ultrafine (UF) particles and specific pulmonary cell populations. We will use cell lines and primary cells derived from mouse, rat, and human to test the overall hypothesis of the Rochester PM Center that increased morbidity and mortality in susceptible populations is due to the unique characteristics of UF particles and the heightened sensitivity of the aged organism. The in vitro experiments are intended to provide a link between the whole animal and controlled clinical (human) exposures, described in the other programs of this Particle Center, by elucidating the specific mechanisms that are triggered following particle cell contact.
Progress Summary:During the current funding period, our experiments have focused on the ability of real-world particles to cause cellular responses and the ability of cell-based assays to distinguish different particles based on their source and composition.
Source Dependent Induction of Gene Expression
Experiment 1a Laboratory Generated Particles of Defined Composition. During the current year, we planned to extend our studies by examining the effects of specific metal components on cellular responses. Using the particle generation core of the PM Center, we assayed particles of varying metal composition to assess the role of redox active metals (e.g., Fe, Cu, Zn) on Il-8 (as a prototypic oxidant sensitive gene) promoter activity. The concentrations range from 0.5 to 50 μg/cm2 (Figure 1). This range is chosen based on data collected during the previous funding cycle.
Figure 1. Pulmonary Epithelial Cell Production of PGE2 in Response to UF Particles of Varying Composition
Figure 2.Endothelial Cell Production of PGE2 in Response to UF PM
Using similar experimental tools as described above, we examined the effect of coarse, fine, and UF size particles collected by high volume samplers at multiple sites in North America and Europe to establish a relationship between changes in gene expression and oxidant stress and size as well as source of ambient particles. This was part of a multicenter collaborative in vitro assessment of concentrated ambient particles being established among the existing PM centers. Based on studies in Core 3 (Clinical Studies) and Core 4 (In Vivo Animal Studies), we evaluated these particles in both pulmonary epithelial cells and vascular endothelial cells (Figure 2). The rationale for this choice is the apparent increased in vivo sensitivity of the vascular compartment to UF particle stimulation. When particulate matter (PM) from seven different sites was added to cultures of epithelial cells and endothelial cells, we found high activity in both cell types with the coarse reaction. No specificity for any location or composition was evident. In contrast, studies with UF PM and endothelial cells revealed (Figure 3) that the PM could be sorted into two distinct groups. This was only evident in endothelial cultures using IL-6 as the outcome measure. Currently, we are continuing to evaluate this response and attempting to identify the particular component in these fractions that was responsible for this effect.
Figure 3. Endothelial Response to UFPM (normalized to TiO2)
Specific Aim 2: Mechanism Stimulation of Gene Expression
We propose to continue our studies of how age-enhanced inflammatory gene expression reacts in response to PM. The basic approach planned is to use PM, both laboratory generated and from ambient sources, to establish age effects.
Recent work has continued the refinement of in vitro models of particle cell interactions with the goal to define mechanisms of cellular activation, the effects of age or prior activation on cytokine gene activation and differential responses of epithelial cells, and macrophages and vascular endothelial cells to particles of different size and composition. In detailed studies of transcription factor activation in response to PM, it appears that both NFkB and AP-1 activation play a role in the PM response.
Future Activities:In the coming year, we plan to continue to characterize the difference in response to stimuli, alone and in combination, as a function of age. We also expect to extend these studies from macrophages to parenchymal cells, fibroblasts, and epithelial cells. We also will investigate other markers of response. Measurement of prostaglandin production and COX-2 activation will be evaluated with respect to its usefulness as a marker. Studies have shown COX-2 to be important in the induction of the inflammatory response and systemic responses.
Also, in support of the in vivo projects, we will evaluate in vitro effects of particles of differing composition. We will continue to examine the cytokine response to UF particles containing elemental carbon as well as iron and organic carbon compounds and begin studies of concentrated real-world particles.
Journal Articles:No journal articles submitted with this report: View all 9 publications for this subproject
Supplemental Keywords:pollution prevention, urban air pollution, atmosphere, metals, air, health, waste, atmospheric sciences, biochemistry, children’s health, environmental chemistry, epidemiology, genetics, virology, molecular biology, health risk assessment, risk assessments, incineration, combustion, combustion engines, air toxics, tropospheric ozone, PM2.5, particulates, ultrafine particles, particulate matter, particle exposure, particle size, aerosol, aerosols, ambient air, ambient air monitoring, ambient air quality, animal model, atmospheric, cardiopulmonary, cardiopulmonary responses, cardiovascular disease, cardiovascular vulnerability, coronary artery disease, cytokine production, fine particles, human exposure, human health, human health effects, environmental health effects, inhalation toxicology, lead, lung, lung inflammation, metals, morbidity, mortality, pathophysiological mechanisms, pulmonary, pulmonary disease, stratospheric ozone, sensitive populations, susceptible populations,
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Air, Scientific Discipline, Health, RFA, Molecular Biology/Genetics, Toxicology, Risk Assessments, Health Risk Assessment, air toxics, Atmospheric Sciences, Biochemistry, particulate matter, Environmental Chemistry, aerosols, cardiopulmonary, risk assessment, susceptible populations, ultrafine particles, altered gene expression, urban environment, aerosol, ambient air quality, cardiovascular disease, cardiovascular vulnerability, coronary artery disease, health effects, mortality, lung inflamation, inhalation toxicology, ambient air, fine particles, environmental health effects, cardiopulmonary responses, human health risk, cytokine production, particle exposure, biostatistics, human health effects, particulates, sensitive populations, ambient monitoring, lung, metals, ambient air monitoring, pathophysiological mechanisms, atmospheric, pulmonary, urban air pollution, human health, cell kinetic models, morbidity, particle size, PM, pulmonary disease, animal model
Relevant Websites:
http://www2.envmed.rochester.edu/envmed/PMC/
Progress and Final Reports:
1999 Progress Report
2000 Progress Report
2001 Progress Report
2002 Progress Report
2003 Progress Report
Original Abstract
Final Report
Main Center Abstract and Reports:
R827354 Airborne PM - Rochester PM Center
Subprojects under this Center:
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R827354C001 Characterization of the Chemical Composition of Atmospheric Ultrafine Particles
R827354C002 Inflammatory Responses and Cardiovascular Risk Factors in Susceptible Populations
R827354C003 Clinical Studies of Ultrafine Particle Exposure in Susceptible Human Subjects
R827354C004 Animal Models: Dosimetry, and Pulmonary and Cardiovascular Events
R827354C005 Ultrafine Particle Cell Interactions: Molecular Mechanisms Leading to Altered Gene Expression
R827354C006 Development of an Electrodynamic Quadrupole Aerosol Concentrator
R827354C007 Kinetics of Clearance and Relocation of Insoluble Ultrafine Iridium Particles From the Rat Lung Epithelium to Extrapulmonary Organs and Tissues (Pilot Project)
R827354C008 Ultrafine Oil Aerosol Generation for Inhalation Studies