Faculty Bibliography

This prospective nonrandomized open-label cohort study addresses the safety and efficacy of exosomes (ExoFloâ„¢) derived from allogeneic bone marrow mesenchymal stem cells as treatment for severe COVID-19. During April 2020, ExoFlo was provided to 24 SARS-CoV-2 polymerase chain reaction-positive patients at a single hospital center, all of whom met criteria for severe COVID-19 as well as moderate-to-severe acute respiratory distress syndrome. Patients received a single 15 mL intravenous dose of ExoFlo and were evaluated for both safety and efficacy from days 1 to 14 post-treatment. All safety endpoints were met with no adverse events observed within 72 h of ExoFlo administration. A survival rate of 83% was observed. In total, 17 of 24 (71%) patients recovered, 3 of 24 (13%) patients remained critically ill though stable, and 4 of 24 (16%) patients expired for reasons unrelated to the treatment. Overall, after one treatment, patients' clinical status and oxygenation improved with an average pressure of arterial oxygen to fraction of inspired oxygen ratio (PaO₂/FiO₂) increase of 192% (P < 0.001). Laboratory values revealed significant improvements in absolute neutrophil count [mean reduction 32% (P value <0.001)] and lymphopenia with average CD3⁺, CD4⁺, and CD8⁺ lymphocyte counts increasing by 46% (P < 0.05), 45% (P < 0.05), and 46% (P < 0.001), respectively. Likewise, acute phase reactants declined, with mean C-reactive protein, ferritin, and D-dimer reduction of 77% (P < 0.001), 43% (P < 0.001), and 42% (P < 0.05), respectively. In conclusion, owing to its safety profile, capacity to restore oxygenation, downregulate cytokine storm, and reconstitute immunity, ExoFlo is a promising therapeutic candidate for severe COVID-19. Future randomized controlled trials (RCTs) are needed to determine ExoFlo therapeutic potential.

Pulmonary disease after World Trade Center particulate matter(WTC-PM) exposure is associated with dyslipidemia and the receptor for advanced glycation end products (RAGE); however, the mechanisms are not well understood. We utilized a murine model and a multiOMIC assessment to understand the role of RAGE in the pulmonary long-term effects of a single high intensity exposure to WTC-PM. After 1-month(1-M), WTC-PM exposed wild-type(WT) mice had airway hyperreactivity(AHR) while RAGE-deficient(Ager-/-) were protected. PM-exposed WT mice also had histologic evidence of airspace disease while Ager-/- remained unchanged. Inflammatory mediators such as G-CSF, IP-10, and KC were differentially expressed after WTC-PM exposure. WTC-PM induced α-SMA, DIAPH1, RAGE and significant lung collagen deposition in WT compared to Ager-/-. Compared to WT with PM exposure, relative expression of phosphorylated to total CREB and JNK were significantly increased in the lung of PM-exposed Ager-/-, whereas Akt was decreased. Random forests of the refined lung metabolomic profile classified subjects with 92% accuracy; principal components analysis captured 86.7% of the variance in 3 components and demonstrated prominent sub-pathway involvement including known mediators of lung disease such as vitamin B6 metabolites, sphingolipids, fatty acids, and phosphatidylcholines. Treatment with a partial RAGE antagonist, pioglitazone, yielded similar fold-change expression of metabolites(N6-carboxymethyllysine, 1-methylnicotinamide, (N(1)+N(8))-acetylspermidine and Succinylcarnitine(C4-DC)) between WT and Ager-/- exposed to WTC-PM. RAGE can mediate WTC-PM-induced AHR, and warrants further investigation.

Vascular changes occur early in the development of obstructive airways disease. However, the vascular remodeling and dysfunction due to World Trade Center-Particulate Matter (WTC-PM) exposure are not well described and are therefore the focus of this investigation. C57Bl/6 female mice oropharyngeally aspirated 200 µg of WTC-PM₅₃ or phosphate-buffered saline (PBS) (controls). 24-hours (24-hrs) and 1-Month (1-M) after exposure, echocardiography, micro-positron emission tomography(µ-PET), collagen quantification, lung metabolomics, assessment of antioxidant potential and soluble-receptor for advanced glycation end products (sRAGE) in bronchoalveolar lavage(BAL) and plasma were performed. 24-hrs post-exposure, there was a significant reduction in (1) Pulmonary artery(PA) flow-velocity and pulmonary ejection time(PET) (2) Pulmonary acceleration time(PAT) and PAT/PET, while (3) Aortic ejection time(AET) and velocity time integral(VTI) were increased, and (4) Aortic acceleration time (AAT)/AET, cardiac output and stroke volume were decreased compared to controls. 1-M post-exposure, there was also significant reduction of right ventricular diameter as right ventricle free wall thickness was increased and an increase in tricuspid E, A peaks and an elevated E/A. The pulmonary and cardiac standard uptake value and volume 1-M post-exposure was significantly elevated after PM-exposure. Similarly, α-smooth muscle actin(α-SMA) expression, aortic collagen deposition was elevated 1-M after PM exposure. In assessment of the metabolome, prominent subpathways included advanced glycation end products (AGEs), phosphatidylcholines, sphingolipids, saturated/unsaturated fatty acids, eicosanoids, and phospholipids. BAL superoxide dismutase(SOD), plasma total-antioxidant capacity activity, and sRAGE (BAL and plasma) were elevated after 24-hrs. PM exposure and associated vascular disease are a global health burden. Our study shows persistent WTC-Cardiorespiratory and Vascular Dysfunction (WTC-CaRVD), inflammatory changes and attenuation of antioxidant potential after PM exposure. Early detection of vascular disease is crucial to preventing cardiovascular deaths and future work will focus on further identification of bioactive therapeutic targets.

RATIONALE/BACKGROUND: < LLN). METHODS: < LLN was associated with an increased QCT-measured PAAr, adjusting for previously identified important covariates. RESULTS: < LLN with PAAr (OR 1.63, 95% CI 1.21, 2.20, P = 0.0015) and all the unadjusted associations, except for PCL score. CONCLUSIONS: < LLN is associated with elevated PAAr which, although likely multifactorial, may be related to distal vasculopathy, as has been hypothesized for chronic obstructive pulmonary disease.