Faculty Bibliography

The destruction of the World Trade Center (WTC) on September 11, 2001 (9/11) released large amounts of toxic dusts and fumes into the air that exposed many community members who lived and/or worked in the local area. Many community members, defined as WTC survivors by the federal government, developed lower respiratory symptoms (LRS). We previously reported the persistence of these symptoms in patients with normal spirometry despite treatment with inhaled corticosteroids and/or long-acting bronchodilators. This report expands upon our study of this group with the goal to identify molecular markers associated with exposure and heterogeneity in WTC survivors with LRS using a selected plasma biomarker approach. Samples from WTC survivors with LRS (n = 73, WTCS) and samples from healthy control participants of the NYU Bellevue Asthma Registry (NYUBAR, n = 55) were compared. WTCS provided information regarding WTC dust exposure intensity. Hierarchical clustering of the linear biomarker data identified two clusters within WTCS and two clusters within NYUBAR controls. Comparison of the WTCS clusters showed that one cluster had significantly increased levels of circulating matrix metalloproteinases (MMP1, 2, 3, 8, 12, 13), soluble inflammatory receptors (receptor for advanced glycation end-products-RAGE, Interleukin-1 receptor antagonist (IL-1RA), suppression of tumorigenicity (ST)2, triggering receptor expressed on myeloid cells (TREM)1, IL-6Ra, tumor necrosis factor (TNF)RI, TNFRII), and chemokines (IL-8, CC chemokine ligand- CCL17). Furthermore, this WTCS cluster was associated with WTC exposure variables, ash at work, and the participant category workers; but not with the exposure variable WTC dust cloud at 9/11. A comparison of WTC exposure categorial variables identified that chemokines (CCL17, CCL11), circulating receptors (RAGE, TREM1), MMPs (MMP3, MMP12), and vascular markers (Angiogenin, vascular cell adhesion molecule-VCAM1) significantly increased in the more exposed groups. Circulating biomarkers of remodeling and inflammation identified clusters within WTCS and were associated with WTC exposure.

BACKGROUND:Blood eosinophils are used to determine eligibility for agents targeting IL-5 in patients with uncontrolled asthma. However, little is known about the variability of blood eosinophil measures in these patients before treatment initiation. OBJECTIVE:To characterize variability and patterns of variability of blood eosinophil levels in a real-world clinic for severe asthmatics. METHODS:Retrospective review of blood eosinophils measured over a 5-year period in patients enrolled in an urban clinic. Repeated measures of blood eosinophil levels in individuals were evaluated and cluster analysis was performed to characterize patients by eosinophil patterns. Clinical characteristics associated with eosinophil levels and patterns of variability were analyzed. RESULTS:Patients treated in the Bellevue Hospital Asthma Clinic within a 3-month period were identified (n = 219). Blood eosinophil measures were obtained over the previous 5 years. Only 6% (n= 13) of patients had levels that were consistently above 300 cells/μL. Nearly 50% (n = 104) had eosinophil levels that traversed the threshold of 300 cells/μL. In contrast, 102 (46%) had levels that never reached the threshold of 300 cells/μL. Cluster analyses revealed three clusters with differing patterns of levels and variability. There was a suggestion of decreased clinical control and increased atopy in the cluster with the greatest variability in blood eosinophil measures. CONCLUSION/CONCLUSIONS:In an urban clinic for patients referred for uncontrolled asthma, blood measures of eosinophils were variable and showed differing patterns of variability. These data reinforce the need to perform repeated eosinophil blood measures for appropriate designation for therapeutic intervention.

The European guidelines, which focus on clinical aspects of pulmonary hypertension (PH), provide only minimal information about the pathophysiological concepts of PH. Here, we review this topic in greater detail, focusing on specific aspects in the pathobiology, pathology and genetics, which include mechanisms of vascular inflammation, the role of transcription factors, ion channels/ion channel diseases, hypoxic pulmonary vasoconstriction, genetics/epigenetics, metabolic dysfunction, and the potential future role of histopathology of PH in the modern era of PH therapy. In addition to new insights in the pathobiology of this disease, this working group of the Cologne Consensus Conference also highlights novel concepts and potential new therapeutic targets to further improve the treatment options in PAH.

Detrimental effects of air pollution with fine dust (particulate matter ≤2.5 μm in aerodynamic diameter, or PM_2.5) on the systemic circulation and the left heart have been studied intensely during the past decade. In comparison, knowledge regarding the effects of exposure to air pollution with PM_2.5 on the pulmonary vasculature and the right heart lags far behind. A report on severe lung disease and right heart failure in coal miners was published nearly 170 years ago. However, today, we still do not have a clear picture of how the effect of air pollution on the pulmonary circulation or the right heart should be viewed from a clinical, mechanistic biological, therapeutic, or economic angle. In the laboratory, we have established a model of immune response-induced vascular remodeling that is significantly worsened by adding PM_2.5 to the intranasal antigen challenge solution. Importantly, the PM_2.5 is given at a concentration that by itself does not induce significant inflammation or pulmonary vascular remodeling. However, when added to antigen, this low-dose PM_2.5 exposure induces severe pulmonary vascular remodeling, significantly increased right ventricular pressures, and significant molecular changes in the right heart. Our data also show that these PM_2.5-exaggerated responses are dependent on interleukin-13, interleukin-17A, and antigen-specific antibody. The experimental model is being used to address a few questions: 1. Which mechanism protects the animals from severe right ventricular failure despite the severity of the pulmonary artery remodeling? 2. What is the mechanism by which PM_2.5 worsens the response to antigen? 3. How does PM_2.5 exert its effects across the small airways to the small blood vessels? In conclusion, further investigation is urgently needed to understand the effects of exposure to ambient or occupational air pollution on the pulmonary vasculature, because better knowledge could lead to immediate beneficial actions for patients with pulmonary hypertension and persons at risk.