2016 Progress Report: Cardiovascular Consequences of Immune Modification by Traffic-Related Emissions

EPA Grant Number: R834796C003
Subproject: this is subproject number 003 , established and managed by the Center Director under grant R834796
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: University of Washington Center for Clean Air Research
Center Director: Vedal, Sverre
Title: Cardiovascular Consequences of Immune Modification by Traffic-Related Emissions
Investigators: Campen, Matthew J. , McDonald, Jacob D. , Rosenfeld, Michael
Current Investigators: Campen, Matthew J. , Lund, Amie K. , McDonald, Jacob D. , Rosenfeld, Michael
Institution: University of New Mexico , Lovelace Respiratory Research Institute , University of Washington , Washington State University
Current Institution: Lovelace Respiratory Research Institute , University of New Mexico , University of Washington
EPA Project Officer: Callan, Richard
Project Period: December 1, 2010 through November 30, 2015 (Extended to November 30, 2017)
Project Period Covered by this Report: August 1, 2015 through July 31,2016
RFA: Clean Air Research Centers (2009) RFA Text |  Recipients Lists
Research Category: Health Effects , Air

Objective:

Traffic-related emissions are associated with the incidence and progression of acute and chronic cardiovascular sequelae in human population studies. Such phenomena of near-roadway health effects have yet to be characterized toxicologically. Because of overlapping issues related to noise, socioeconomic status, ethnicity, etc., there is a need to better understand the biological plausibility that fresh mixtures of vehicular emissions have a more potent than expected impact on human health. We hypothesize that the complex mixtures produced by traffic are inherently more toxic due to the combined presence of both particulates and volatile organic emissions. Furthermore, we hypothesize that emissions-induced oxidation of certain endogenous phospholipids, presumably from the pulmonary surfactant, can stimulate the activity of immune cells through such receptors and in turn promote the invasion of existing vascular lesions.

Approach: This project uses complex roadway mixtures as generated and characterized in the laboratory. In Aim 1, we will ascertain 1) the potentiating effects of physical and photochemical aging on fresh emissions and 2) interactions of vehicular emissions with pertinent copollutants (ozone, road dust), both in terms of driving systemic vascular oxidative stress. In Aim 2, we will examine effects of the emissions-induced oxidative modifications to endogenous phospholipids, in terms of activating immune-modulating receptors such as LOX-1, CD-36, TLR-2, and TLR-4. This Aim will utilize transgenic models to examine the roles of these receptors, as well as characterize the lipidomic alterations in various tissues. Lastly, in Aim 3, we will further explore the role of specific immune cell populations as participants in the innate and adaptive responses to emissions-induced phospholipid modifications. In this Aim, we will utilize mouse models of immunodeficiency, including SCID and B-Cell deficient models. Additionally, we will pursue bone-marrow transplants from mice lacking those receptors described in Aim 2 to mechanistically establish the involvement of the oxidatively-modified phospholipids.

Responding to suggestions from the scientific advisory committee, we have focused on the nature and bioactivity of circulating factors induced by pollutant exposures, as these appear to be ligands that interact with the scavenger receptors of interest in Aims 2 and 3. This has been an area of significant progress for the past year.

Expected Results: Findings will 1) indicate the most potent combinations of urban roadway and background copollutants in terms of vascular toxicity and 2) detail the role of the immune system in mechanistically driving the systemic effects of inhaled pollutants.

Progress Summary:

Research this past year has focused on toxicological studies using the exposure atmospheres described in the Project 2 summary. We investigated the impact of particle size on gas-particle interactions in terms of pulmonary and systemic toxicity. As demonstrated in Figure 1, the overall impact of the exposures on inflammation and injury in the lung was minimal for both strains of mice. However, we observed that surface area-dependent gas-particle interaction impacted PM uptake by macrophages (Figures 2 and 3). Similarly, BALF cytokines TNFα and CXCL1 were significantly elevated after UFP+G exposure for both C57BL/6 and ApoE-/- mice (Figure 4). These findings suggest that smaller particles, with a greater surface area, exhibit potentiated pulmonary responses when combined with gaseous copollutants from combustion sources.

Text Box:  
Figure 1. Pulmonary inflammation and injury by exposure condition. The top row shows results for C57BL/6 mice, and the bottom row shows results for ApoE-/- mice. The left, middle, and right plots are total cell count, LDH activity, and total protein, respectively.

Text Box:  
Figure 2. Representative particulate matter uptake by macrophages for FA (left), UFP (center), and UFP+G (right) exposures.

Text Box:  
Figure 3. Quantification of macrophage particulate matter uptake in C57BL/6 (left) and ApoE-/- (right) mice. A score of 0 reflects no observable particles present.  The middle image in figure 2 reflects a score of 1.  The right image in figure 3 reflects a score of 5. Scoring was conducted by a technician blinded to the exposure groupings.

 

Text Box:  
Figure 4. Bronchoalveolar lavage TNFα concentrations (left plots) and CXCL1 concentrations 
(right plots) for C57BL/6 (left hand side of plots) and ApoE-/- mice
 (right hand side of plots).

Beyond the lung, we also examined neuroinflammatory markers in the hippocampus of exposed mice using qPCR techniques. Especially in ApoE-/- mice, the pattern of increase in IL-6 and TGFb mRNA mirrored the pulmonary findings, again suggesting the most potent effect arose from the UFP+G group.

Recent studies at the UW (Rosenfeld Lab) have focused on the quantitation of anti-oxidized phospholipid antibodies in blood samples from diesel exhaust exposed humans and from diesel and mixed vehicular emission exposed rodents generated from projects 2, 3 and 4. We had previously shown about a 2 fold increase in these antibodies in plasma from apo E-/- mice exposed to diesel exhaust for 2 weeks as compared to plasma from non-exposed mice (see Table 1).

                                                                                    Absorbance

PBS/BSA (Blank)

0.181

0.190

0.191

0.180

Apo E DE Plasma

1.494

0.782

0.514

0.339

Apo E DE Plasma

1.362

0.802

0.496

0.362

Apo E Non DE Plasma

0.580

0.374

0.227

0.249

Apo E Non DE Plasma

0.496

0.376

0.284

0.312

EO6 Positive Control

0.346

0.406

0.448

0.396

Table 1.

We are currently ramping up production (hybridomas) and isolation of the antibody used in the sandwich assay for the plasma content of E06 (anti-phospholipid antibody) and will be measuring the content of E06 in the plasma samples obtained from projects 2, 3, and 4.

 

Future Activities:

Finalize biological assays from the UFP vs FP study and complete publications. Complete collaborative projects.


Journal Articles on this Report : 9 Displayed | Download in RIS Format

Other subproject views: All 26 publications 16 publications in selected types All 16 journal articles
Other center views: All 187 publications 87 publications in selected types All 86 journal articles
Type Citation Sub Project Document Sources
Journal Article Brower JB, Doyle-Eisele M, Moeller B, Stirdivant S, McDonald JD, Campen MJ. Metabolomic changes in murine serum following inhalation exposure to gasoline and diesel engine emissions. Inhalation Toxicology 2016;28(5):241-250. R834796 (2016)
R834796 (Final)
R834796C003 (2016)
R834796C003 (Final)
  • Full-text from PubMed
  • Abstract from PubMed
  • Associated PubMed link
  • Abstract: Taylor & Francis-Abstract
    Exit
  • Other: ResearchGate-Abstract
    Exit
  • Journal Article Robertson S, Colombo ES, Lucas SN, Hall PR, Febbraio M, Paffett ML, Campen MJ. CD36 mediates endothelial dysfunction downstream of circulating factors induced by O3 exposure. Toxicological Sciences 2013;134(2):304-311. R834796 (2013)
    R834796 (2014)
    R834796 (2015)
    R834796 (Final)
    R834796C003 (2013)
    R834796C003 (2016)
    R834796C003 (Final)
    R833990 (2011)
  • Full-text from PubMed
  • Abstract from PubMed
  • Associated PubMed link
  • Full-text: Oxford Journals-Full Text HTML
    Exit
  • Abstract: Oxford Journals-Abstract
    Exit
  • Other: Oxford Journals-Full Text PDF
    Exit
  • Journal Article Yin F, Lawal A, Ricks J, Fox JR, Larson T, Navab M, Fogelman AM, Rosenfeld ME, Araujo JA. Diesel exhaust induces systemic lipid peroxidation and development of dysfunctional pro-oxidant and pro-inflammatory high-density lipoprotein. Arteriosclerosis, Thrombosis, and Vascular Biology 2013;33(6):1153-1161. R834796 (2013)
    R834796 (2014)
    R834796 (2015)
    R834796 (Final)
    R834796C003 (2013)
    R834796C003 (2016)
    R834796C003 (Final)
  • Abstract from PubMed
  • Full-text: American Heart Association-Full Text HTML
    Exit
  • Abstract: American Heart Association-Abstract
    Exit
  • Other: American Heart Association-Full Text PDF
    Exit
  • Journal Article Peroxidation and Development of Dysfunctional Pro-Oxidant and Pro-Inflammatory High-Density Lipoprotein. Arterioscler Thromb Vasc Biol. 2013, 33(6):1153-61. R834796C003 (2016)
    not available
    Journal Article Aragon MJ, Chrobak I, Brower J, Roldan L, Fredenburgh LE, McDonald JD, Campen MJ:Inflammatory and Vasoactive Effects of Serum Following Inhalation of Varied Complex Mixtures. Cardiovascular toxicology. 2016, 16(2):163-171. R834796C003 (2016)
    not available
    Journal Article Campen MJ, Lund A, Rosenfeld M:Mechanisms linking traffic-related air pollution and atherosclerosis. Current opinion in pulmonary medicine. 2012, 18(2):155. R834796C003 (2016)
    not available
    Journal Article Campen M, Robertson S, Lund A, Lucero J, McDonald J:Engine exhaust particulate and gas phase contributions to vascular toxicity. Inhalation toxicology. 2014, 26(6):353-360. R834796C003 (2016)
    not available
    Journal Article Paffett ML, Sheppard L, Robertson S, Weaver J, Lucas SN, Campen MJ. Ozone inhalation enhances coronary artery constriction and impairs dilation via superoxide-dependent mechanisms. Toxicol Appl Pharmacol. 2015, In press. R834796C003 (2016)
    not available
    Journal Article Schisler J, Campen MJ, Madden M, and Willis MS. Transcriptional Endothelial Biosensor Response to Diesel-Induced Plasma Compositional Changes. Inhalation Toxicology. 2015, 27(5):272–280. R834796C003 (2016)
    not available

    Supplemental Keywords:

    Coronary Artery Disease, Oxidized Phospholipids, Atherosclerosis, Particulate Matter, Volatile Organic Compounds, Carbon Monoxide, Ozone, Health, Scientific Discipline, Air, ENVIRONMENTAL MANAGEMENT, Air Quality, air toxics, Health Risk Assessment, Risk Assessments, mobile sources, Biochemistry, Environmental Monitoring, Risk Assessment, ambient air quality, atmospheric particulate matter, particulate matter, aerosol particles, air pollutants, motor vehicle emissions, vehicle emissions, air quality models, motor vehicle exhaust, airway disease, bioavailability, air pollution, particle exposure, atmospheric aerosols, ambient particle health effects, vascular dysfunction, cardiotoxicity, atmospheric chemistry, exposure assessment

    Relevant Websites:

    University of Washington Center for Clear Air Research Exit

    Progress and Final Reports:

    Original Abstract
  • 2011 Progress Report
  • 2012 Progress Report
  • 2013 Progress Report
  • 2014
  • 2015 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R834796    University of Washington Center for Clean Air Research

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R834796C001 Exposure Mapping – Characterization of Gases and Particles for ExposureAssessment in Health Effects and Laboratory Studies
    R834796C002 Simulated Roadway Exposure Atmospheres for Laboratory Animal and Human Studies
    R834796C003 Cardiovascular Consequences of Immune Modification by Traffic-Related Emissions
    R834796C004 Vascular Response to Traffic-Derived Inhalation in Humans
    R834796C005 Effects of Long-Term Exposure to Traffic-Derived Particles and Gases on Subclinical Measures of Cardiovascular Disease in a Multi-Ethnic Cohort