Showing papers by "Serpil C. Erzurum published in 2022"

A comprehensive SARS-CoV-2–human protein–protein interactome reveals COVID-19 pathobiology and potential host therapeutic targets

Abstract: Studying viral-host protein-protein interactions can facilitate the discovery of therapies for viral infection. We use high-throughput yeast two-hybrid experiments and mass spectrometry to generate a comprehensive SARS-CoV-2-human protein-protein interactome network consisting of 739 high-confidence binary and co-complex interactions, validating 218 known SARS-CoV-2 host factors and revealing 361 novel ones. Our results show the highest overlap of interaction partners between published datasets and of genes differentially expressed in samples from COVID-19 patients. We identify an interaction between the viral protein ORF3a and the human transcription factor ZNF579, illustrating a direct viral impact on host transcription. We perform network-based screens of >2,900 FDA-approved or investigational drugs and identify 23 with significant network proximity to SARS-CoV-2 host factors. One of these drugs, carvedilol, shows clinical benefits for COVID-19 patients in an electronic health records analysis and antiviral properties in a human lung cell line infected with SARS-CoV-2. Our study demonstrates the value of network systems biology to understand human-virus interactions and provides hits for further research on COVID-19 therapeutics.

The Impact of Insulin Resistance on Loss of Lung Function and Response to Treatment in Asthma.

Abstract: RATIONALE The role of obesity-associated insulin resistance (IR) in airflow limitation in asthma is uncertain. OBJECTIVES Using data in the Severe Asthma Research Program 3 (SARP-3), we evaluated relationships between homeostatic measure of IR (HOMA-IR), lung function (cross sectional and longitudinal analyses) and treatment responses to bronchodilators and corticosteroids. METHODS HOMA-IR values was categorized as without (< 3.0), moderate (3.0-5.0), or severe (>5.0). Lung function included forced expired volume in one second (FEV1) and forced vital capacity (FVC) measured before and after treatment with inhaled albuterol and intramuscular triamcinolone acetonide (TA) and yearly for 5 years. MEASUREMENTS AND MAIN RESULTS Among 307 participants in SARP-3, 170 (55%) were obese and 140 (46%) had IR. Compared to patients without IR, those with IR had significantly lower values for forced expired volume in one second (FEV1) and forced vital capacity (FVC), and these lower values were not attributable to obesity effects. Compared to patients without IR, those with IR had lower FEV1 responses to beta adrenergic agonists and systemic corticosteroids. The annualized decline in FEV1 was significantly greater in patients with moderate IR (-41 mLs/year) and severe IR (-32 mLs/year,) than in patients without IR (-13mLs/year, p< 0.001 for both comparisons). CONCLUSION IR is common in asthma and is associated with lower lung function, accelerated loss of lung function, and suboptimal lung function responses to bronchodilator and corticosteroid treatments. Clinical trials in patients with asthma and IR are needed to determine if improving IR might also improve lung function.

Whole Genome Association Study of the Plasma Metabolome Identifies Metabolites Linked to Cardiometabolic Disease in Black Individuals

Abstract: Integrating genetic information with metabolomics has provided new insights into genes affecting human metabolism. However, gene-metabolite integration has been primarily studied in individuals of European Ancestry, limiting the opportunity to leverage genomic diversity for discovery. In addition, these analyses have principally involved known metabolites, with the majority of the profiled peaks left unannotated. Here, we perform a whole genome association study of 2,291 metabolite peaks (known and unknown features) in 2,466 Black individuals from the Jackson Heart Study. We identify 519 locus-metabolite associations for 427 metabolite peaks and validate our findings in two multi-ethnic cohorts. A significant proportion of these associations are in ancestry specific alleles including findings in APOE, TTR and CD36. We leverage tandem mass spectrometry to annotate unknown metabolites, providing new insight into hereditary diseases including transthyretin amyloidosis and sickle cell disease. Our integrative omics approach leverages genomic diversity to provide novel insights into diverse cardiometabolic diseases.

Low CC16 mRNA Expression Levels in Bronchial Epithelial Cells Are Associated with Asthma Severity.

Abstract: RATIONALE CC16 is a protein mainly produced by non-ciliated bronchial epithelial cells (BEC) that participates in host defense. Reduced CC16 protein levels in bronchoalveolar lavage and serum are associated with asthma susceptibility. OBJECTIVES Few studies have investigated the relationship of CC16 and asthma progression, and none has focused on BEC. In this study, we sought to determine if CC16 mRNA expression levels in BEC are associated with asthma severity. METHODS Association analyses between CC16 mRNA expression levels in BEC (242 asthmatics and 69 controls) and asthma-related phenotypes in the Severe Asthma Research Program (SARP) were performed using a generalized linear model. MEASUREMENTS AND MAIN RESULTS Low CC16 mRNA expression levels in BEC were significantly associated with asthma susceptibility and asthma severity, high systemic corticosteroids use, high retrospective and prospective asthma exacerbations, and low pulmonary function. Low CC16 mRNA expression levels were significantly associated with high T2 inflammation biomarkers (fractional exhaled nitric oxide (FeNO) and sputum eosinophils). CC16 mRNA expression levels were negatively correlated with expression levels of Th2 genes (IL1RL1, POSTN, SERPINB2, CLCA1, NOS2, and MUC5AC), and positively correlated with expression levels of Th1 and inflammation genes (IL12A and MUC5B). A combination of two non-T2 biomarkers (CC16 and IL-6) revealed four asthma endotypes with different characteristics of T2 inflammation, obesity, and asthma severity. CONCLUSIONS Our findings indicate that low CC16 mRNA expression levels in BEC are associated with asthma susceptibility, severity, and exacerbations, partially through immunomodulation of T2 inflammation. CC16 is a potential non-T2 biomarker for asthma development and progression.

Low levels of nitric oxide promotes heme maturation into several hemeproteins and is also therapeutic

Abstract: Nitric oxide (NO) is a signal molecule and plays a critical role in the regulation of vascular tone, displays anti-platelet and anti-inflammatory properties. While our earlier and current studies found that low NO doses trigger a rapid heme insertion into immature heme-free soluble guanylyl cyclase β subunit (apo-sGCβ), resulting in a mature sGC-αβ heterodimer, more recent evidence suggests that low NO doses can also trigger heme-maturation of hemoglobin and myoglobin. This low NO phenomena was not only limited to sGC and the globins, but was also found to occur in all three nitric oxide synthases (iNOS, nNOS and eNOS) and Myeloperoxidase (MPO). Interestingly high NO doses were inhibitory to heme-insertion for these hemeproteins, suggesting that NO has a dose-dependent dual effect as it can act both ways to induce or inhibit heme-maturation of key hemeproteins. While low NO stimulated heme-insertion of globins required the presence of the NO-sGC-cGMP signal pathway, iNOS heme-maturation also required the presence of an active sGC. These effects of low NO were significantly diminished in the tissues of double (n/eNOS-/-) and triple (n/i/eNOS-/-) NOS knock out mice where lung sGC was found be heme-free and the myoglobin or hemoglobin from the heart/lungs were found be low in heme, suggesting that loss of endogenous NO globally impacts the whole animal and that this impact of low NO is both essential and physiologically relevant for hemeprotein maturation. Effects of low NO were also found to be protective against ischemia reperfusion injury on an ex vivo lung perfusion (EVLP) system prior to lung transplant, which further suggests that low NO levels are also therapeutic.

Powerful, scalable and resource-efficient meta-analysis of rare variant associations in large whole genome sequencing studies

Abstract: Meta-analysis of whole genome sequencing/whole exome sequencing (WGS/WES) studies provides an attractive solution to the problem of collecting large sample sizes for discovering rare variants associated with complex phenotypes. Existing rare variant meta-analysis approaches are not scalable to biobank-scale WGS data. Here we present MetaSTAAR, a powerful and resource-efficient rare variant meta-analysis framework for large-scale WGS/WES studies. MetaSTAAR accounts for relatedness and population structure, can analyze both quantitative and dichotomous traits and boosts the power of rare variant tests by incorporating multiple variant functional annotations. Through meta-analysis of four lipid traits in 30,138 ancestrally diverse samples from 14 studies of the Trans Omics for Precision Medicine (TOPMed) Program, we show that MetaSTAAR performs rare variant meta-analysis at scale and produces results comparable to using pooled data. Additionally, we identified several conditionally significant rare variant associations with lipid traits. We further demonstrate that MetaSTAAR is scalable to biobank-scale cohorts through meta-analysis of TOPMed WGS data and UK Biobank WES data of ~200,000 samples.

Mechanisms of Corticosteroid Resistance in Type 17 Asthma.

Abstract: IL-17A plays an important role in the pathogenesis of asthma, particularly the neutrophilic corticosteroid (CS)-resistant subtype of asthma. Clinical studies suggest that a subset of asthma patients, i.e., Th17/IL-17A-mediated (type 17) CS-resistant neutrophilic asthma, may improve with Th17/IL-17A pathway blockade. However, little is known about the mechanisms underlying type 17 asthma and CS response. In this article, we show that blood levels of lipocalin-2 (LCN2) and serum amyloid A (SAA) levels are positively correlated with IL-17A levels and are not inhibited by high-dose CS usage in asthma patients. In airway cell culture systems, IL-17A induces these two secreted proteins, and their induction is enhanced by CS. Furthermore, plasma LCN2 and SAA levels are increased in mice on a preclinical type 17 asthma model, correlated to IL-17A levels, and are not reduced by glucocorticoid (GC). In the mechanistic studies, we identify CEBPB as the critical transcription factor responsible for the synergistic induction of LCN2 and SAA by IL-17A and GC. IL-17A and GC collaboratively regulate CEBPB at both transcriptional and posttranscriptional levels. The posttranscriptional regulation of CEBPB is mediated in part by Act1, the adaptor and RNA binding protein in IL-17A signaling, which directly binds CEBPB mRNA and inhibits its degradation. Overall, our findings suggest that blood LCN2 and SAA levels may be associated with a type 17 asthma subtype and provide insight into the molecular mechanism of the IL-17A-Act1/CEBPB axis on these CS-resistant genes.

A comprehensive SARS-CoV-2-human protein-protein interactome network identifies pathobiology and host-targeting therapies for COVID-19

Abstract: Physical interactions between viral and host proteins are responsible for almost all aspects of the viral life cycle and the host’s immune response. Studying viral-host protein-protein interactions is thus crucial for identifying strategies for treatment and prevention of viral infection. Here, we use high-throughput yeast two-hybrid and affinity purification followed by mass spectrometry to generate a comprehensive SARS-CoV-2-human protein-protein interactome network consisting of both binary and co-complex interactions. We report a total of 739 high-confidence interactions, showing the highest overlap of interaction partners among published datasets as well as the highest overlap with genes differentially expressed in samples (such as upper airway and bronchial epithelial cells) from patients with SARS-CoV-2 infection. Showcasing the utility of our network, we describe a novel interaction between the viral accessory protein ORF3a and the host zinc finger transcription factor ZNF579 to illustrate a SARS-CoV-2 factor mediating a direct impact on host transcription. Leveraging our interactome, we performed network-based drug screens for over 2,900 FDA-approved/investigational drugs and obtained a curated list of 23 drugs that had significant network proximities to SARS-CoV-2 host factors, one of which, carvedilol, showed promising antiviral properties. We performed electronic health record-based validation using two independent large-scale, longitudinal COVID-19 patient databases and found that carvedilol usage was associated with a significantly lowered probability (17%−20%, P < 0.001) of obtaining a SARS-CoV-2 positive test after adjusting various confounding factors. Carvedilol additionally showed anti-viral activity against SARS-CoV-2 in a human lung epithelial cell line [half maximal effective concentration (EC50) value of 4.1 μM], suggesting a mechanism for its beneficial effect in COVID-19. Our study demonstrates the value of large-scale network systems biology approaches for extracting biological insight from complex biological processes.

Mechanisms of Corticosteroid Resistance in Type 17 Asthma

Abstract: IL-17A plays an important role in the pathogenesis of asthma, particularly the neutrophilic corticosteroid (CS)-resistant subtype of asthma. Clinical studies suggest that a subset of asthma patients, i.e., Th17/IL-17A–mediated (type 17) CS-resistant neutrophilic asthma, may improve with Th17/IL-17A pathway blockade. However, little is known about the mechanisms underlying type 17 asthma and CS response. In this article, we show that blood levels of lipocalin-2 (LCN2) and serum amyloid A (SAA) levels are positively correlated with IL-17A levels and are not inhibited by high-dose CS usage in asthma patients. In airway cell culture systems, IL-17A induces these two secreted proteins, and their induction is enhanced by CS. Furthermore, plasma LCN2 and SAA levels are increased in mice on a preclinical type 17 asthma model, correlated to IL-17A levels, and are not reduced by glucocorticoid (GC). In the mechanistic studies, we identify CEBPB as the critical transcription factor responsible for the synergistic induction of LCN2 and SAA by IL-17A and GC. IL-17A and GC collaboratively regulate CEBPB at both transcriptional and posttranscriptional levels. The posttranscriptional regulation of CEBPB is mediated in part by Act1, the adaptor and RNA binding protein in IL-17A signaling, which directly binds CEBPB mRNA and inhibits its degradation. Overall, our findings suggest that blood LCN2 and SAA levels may be associated with a type 17 asthma subtype and provide insight into the molecular mechanism of the IL-17A–Act1/CEBPB axis on these CS-resistant genes. Visual Abstract Key Points Blood LCN2 and SAA levels may be associated with a type 17 asthma subtype. LCN2 and SAAs are steroid-resistant IL-17A target genes in airway cells. IL-17A–Act1/CEBPB axis is an important regulatory mechanism of LCN2 and SAAs.

DNA sequencing analysis of cystic fibrosis transmembrane conductance regulator gene identifies cystic fibrosis‐associated variants in the Severe Asthma Research Program

Abstract: Heterozygote carriers of potentially pathogenic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have increased asthma risk. However, the frequency and impact of CFTR variation among individuals with asthma is unknown.

Urinary total conjugated 3-bromotyrosine, asthma severity and exacerbation risk.

Abstract: Asthma is an inflammatory disease of the airways characterized by eosinophil recruitment, eosinophil peroxidase release and protein oxidation through bromination, which following tissue remodeling results in excretion of 3-bromotyrosine. Predicting exacerbations and reducing their frequency is critical for the treatment of severe asthma. In this study, we aimed to investigate whether urinary total conjugated bromotyrosine can discriminate asthma severity and predict asthma exacerbations. We collected urine from severe (n = 253) and non-severe (n = 178) asthmatics, and the number of adjudicated exacerbations in one-year longitudinal follow-up were determined among subjects enrolled in the Severe Asthma Research Program, a large-scale NIH-funded consortium. Urine glucuronidated bromotyrosine and total conjugated forms were quantified by hydrolysis with either glucuronidase or methanesulfonic acid, respectively, followed by liquid chromatography tandem mass spectrometry analyses of free 3-bromotyrosine. Blood and sputum eosinophils were also counted. The majority of 3-bromotyrosine in urine was found to exist in conjugated forms, with glucuronidated bromotyrosine representing approximately a third, and free bromotyrosine less than 1% of total conjugated bromotyrosine. Total conjugated bromotyrosine was poorly correlated with blood (r2 = 0.038) or sputum eosinophils (r2 = 0.0069). Compared to non-severe asthmatics, severe asthmatics had significantly higher urinary total conjugated bromotyrosine levels. Urinary total conjugated bromotyrosine was independently associated with asthma severity, correlated with the number of asthma exacerbations, and served as a predictor of asthma exacerbation risk over one-year of follow-up.

A comprehensive SARS-CoV-2-human protein-protein interactome network reveals novel pathobiology and host-targeting therapies for COVID-19

Abstract: Physical interactions between viral and host proteins are responsible for almost all aspects of the viral life cycle and the host’s immune response. Studying viral-host protein-protein interactions is thus crucial for identifying strategies for treatment and prevention of viral infection. Here, we use high-throughput yeast two-hybrid and affinity purification followed by mass spectrometry to generate a comprehensive SARS-CoV-2-human protein-protein interactome network consisting of both binary and co-complex interactions. We report a total of 739 high-confidence interactions, showing the highest overlap of interaction partners among published datasets as well as the highest enrichment for genes differentially expressed in samples (such as upper airway and bronchial epithelial cells) from patients with SARS-CoV-2 infection. Showcasing the utility of our network, we describe a novel interaction between the viral accessory protein ORF3a and the host zinc finger transcription factor ZNF579 to illustrate one of the first examples of a viral factor mediating a direct impact on host transcription. Leveraging our interactome, we performed network-based drug screens for over 2,900 FDA-approved/investigational drugs and obtained a curated list of 21 drugs that had significant network proximities to SARS-CoV-2 host factors, one of which, carvedilol, showed promising antiviral properties. We performed electronic health record-based validation using two independent large-scale, longitudinal COVID-19 patient databases and found that carvedilol usage was associated with a significantly lowered probability (17%-20%, P < 0.001) of obtaining a SARS-CoV-2 positive test after adjusting various confounding factors. Carvedilol additionally showed anti-viral activity against SARS-CoV-2 in a human lung epithelial cell line (EC50 value of 4.1 µM), suggesting a mechanism for its beneficial effect in COVID-19. Our study demonstrates the value of large-scale network systems biology approaches for extracting biological insight from complex biological processes.

Preclinical 4-Dimensional Functional Lung Imaging and Quantification of Regional Airflow: A New Standard in Lung Function Evaluation in Murine Models.

Abstract: The current standard for lung function evaluation in murine models is based on forced oscillation technology, which provides a measure of the total airway function, but cannot provide information on regional heterogeneity in function. Limited detection of regional airflow may contribute to a discontinuity between airway inflammation and airflow obstruction in models of asthma. Here, we describe quantification of regional airway function using novel dynamic quantitative imaging and analysis to quantify and visualize lung motion and regional pulmonary airflow in 4dimensions (4D). Furthermore, temporospatial specific ventilation (SV; ml/ml) is used to determine ventilation heterogeneity (VH) indices for lobar and sub-lobar regions, and are directly compared to ex-vivo biological analyses in the same sub-lobal regions. In contrast, oscillation-based technology in murine genetic models of asthma have failed to demonstrate lung function change despite altered inflammation, whereas 4D functional lung imaging demonstrated diminished regional lung function in genetic models relative to wild type mice. Quantitative functional lung imaging assists in localizing the regional effects of airflow. Our approach reveals repeatable and consistent differences in regional airflow between lung lobes in all models of asthma, suggesting that asthma is characterized by regional airway dysfunctions that are often not detectable in composite measure of lung function. 4D functional lung imaging technology has the potential to transform discovery and development in murine models by mapping out regional areas heterogeneously affected by the disease, thus deciphering pathobiology with greater precision.

Pathological Roles for Endothelial Colony Forming Cells in Neonatal and Adult Lung Disease.

Abstract: Endothelial colony forming cells (ECFCs) are vascular resident and circulating endothelial cell subtypes with potent angiogenic capacity, a hierarchy of single-cell clonogenic potentials, and the ability to participate in de novo blood vessel formation and endothelial repair. Existing literature regarding ECFCs in neonatal and adult pulmonary diseases is confounded by study of ambiguously defined "endothelial progenitor cells," which are often not true ECFCs. This review contrasts adult and fetal ECFCs, discusses the effect of prematurity on ECFCs, and examines their different pathological roles in neonatal and adult pulmonary diseases, such as bronchopulmonary dysplasia, congenital diaphragmatic hernia, pulmonary artery hypertension, pulmonary fibrosis and chronic obstructive pulmonary disease. Therapeutic potential is also discussed in light of available pre-clinical data.

Skeletal Muscle Adiposity and Lung Function Trajectory in the Severe Asthma Research Program (SARP).

Abstract: RATIONALE Extra-pulmonary manifestations of asthma, including fatty infiltration in tissues, may reflect systemic inflammation and influence lung function and disease severity. OBJECTIVES To determine if skeletal muscle adiposity predicts lung function trajectory in asthma. METHODS Adult Severe Asthma Research Program-3 participants with baseline computed tomography imaging and longitudinal post-bronchodilator FEV1%-predicted (median follow-up 5 years [1132 person-years]) were evaluated. The mean (Hounsfield unit [HU]) of the left and right paraspinous muscle density (PSMD) at the 12th thoracic vertebral body was calculated. A lower PSMD reflects higher muscle adiposity. We derived PSMD reference ranges from healthy, non-asthma controls. A linear multivariable mixed-effects model evaluated associations of baseline PSMD, and lung function trajectory stratified by sex. MEASUREMENTS AND MAIN RESULTS Participants included 219 with asthma (67% female, mean (SD) BMI of 32.3 [8.8] kg/m2); and 37 controls (51% female, mean [SD] BMI of 26.3 (4.7) kg/m2). Asthmatic participants had lower adjusted PSMD than controls (42.2 vs. 55.8 HU, p<0.001). In adjusted models, PSMD predicted lung function trajectory in asthmatic females, [(β= -0.47 Δ-slope per 10 HU decrease), p= 0.03], but not males [(β= 0.11 Δ-slope per 10 HU decrease), p= 0.77]. The highest PSMD tertile predicted a 2.9% improvement while the lowest tertile predicted a 1.8% decline in FEV1%-predicted among asthmatic females over 5 years. CONCLUSIONS Asthmatic participants have lower PSMD, reflecting greater muscle fat infiltration. Baseline PSMD predicted lung function decline among females with asthma, but not males. These data support an important role of metabolic dysfunction in lung function decline.

Abstract 388: Role Of The Antiapoptotic C-iap2 On The Generation Of An Endothelial Memory In Schistosomiasis-associated Pulmonary Arterial Hypertension

Abstract: Introduction: Schistosomiasis-associated Pulmonary Arterial Hypertension (Sch-PAH) is a life-threatening complication of chronic S. mansoni infection, which can evolve to heart failure and death. During PAH, hyperproliferation of apoptosis-resistant endothelial cells (ECs) has been extensively reported, but therapeutic approaches to reverse this pathological phenotype remain clinically challenging. Hypothesis: Thus, our hypothesis is that antigenic molecules from S. mansoni eggs amplify the secretion of inhibitor of apoptosis protein 2 (c-IAP2), leading to generation of an abnormal EC memory of survival and the development of PAH. Methods/Results: Previously, we showed that depletion of the anti-apoptotic protein Caveolin-1 (Cav-1) via shedding of extracellular vesicles (EVs) leads to the survival of an abnormal EC phenotype through an unclear mechanism. Analysis of survival-associated genes in isolated murine lung ECs from Flk1 +/GFP ;Cav1 -/- mice, revealed high expression of the anti-apoptotic genes BIRC3 and BIRC5 (which encodes cIAP2 and survivin, respectively) when compared to control ECs. Interesting, exposure to 1 μg/mL of the major S. mansoni egg antigen Sm-p40 induced time-dependent phosphorylation of Cav-1 at residue Tyr14 in human lung microvascular EC (HMVEC-L: 228.2 +/- 38.28% of control; p<0.05; n=4), culminating in c-IAP2 expression with no difference on the constitutive expression of c-IAP1. Furthermore, Sm-p40 treatment of HMVEC-L in the presence of pro-inflammatory mediators IL-6, TNF-α, and ATP induced a significant release of EVs containing c-IAP2. Finally, in vivo analysis of lungs from S. mansoni -infected mice confirmed a significant decrease in Cav-1 expression unique to the egg-dependent granuloma area, indicating that local inflammatory response due to egg-derived antigenic molecules is essential for reprogramming and survival of an abnormal EC phenotype during Sch-PAH. Conclusions: Our data suggest that S. mansoni -induced Cav-1 depletion promotes the secretion of the anti-apoptotic c-IAP2 protein, which may be critical for prolonged survival of a pathogenic EC phenotype during the development of Sch-PAH.

Abstract 15005: Tlr4/py14-Caveolin-1-Mediated Endothelial C-iap2 Expression During Schistosomiasis-Associated Pulmonary Arterial Hypertension

Abstract: Introduction: During schistosomiasis-associated pulmonary arterial hypertension (Sch-PAH), hyperproliferation of abnormal endothelial cells (ECs) contributes to development of severe vascular lesions within the lungs; a life-threatening phenomenon that remains with no target therapy. Hypothesis: Here, we found that antigenic molecules from the major etiological agent of Sch-PAH, i.e., S. mansoni , amplify the secretion of the antiapoptotic protein c-IAP2 via TLR4-pY14Cav-1 signaling pathway, which we hypothesized to contribute to generation of an EC memory of survival and severity of PAH. Methods/Results: Cav-1 deficiency via shedding of extracellular vesicles (EVs) leads to survival of an apoptosis-resistant EC phenotype during idiopathic PAH. Similarly, S. mansoni egg antigens also reduced lung EC-Cav-1 expression, suggesting that Cav-1 also plays a role during pathogen-associated PAH. Cav-1 depletion via EVs precedes its phosphorylation at residue Tyr14 (pY14Cav-1), which in turn, contributes to EV loading. Among apoptotic regulators, IAPs have been found as a cargo of EVs in different conditions, including in TLR4-activated cells. Accordingly, our data indicates that S. mansoni egg antigen p40 also activated TLR4/NFkB-mediated signaling, inducing c-IAP2 expression and a time-dependent phosphorylation of Cav-1 in human lung microvascular EC (HMVEC-L: 228.2 +/- 38.28% of control; p<0.05; n=4). Moreover, although Sm-p40 alone was unable to induce shedding of EVs, combination with NFkB-associated proinflammatory mediators (TNF-α, IL-6, and ATP), significantly increased EV shedding by HMVEC-L, suggesting that S. mansoni may epigenetically prime ECs, but co-factors are required to induce EV shedding. Finally, Sch-PAH model using EC- Cav1 -/- mice ( End-scl.Cre ERT2 ;Rosa mt/mg ;Cav1 fl/fl ) revealed that Cav-1 absence led to accumulation of eggs within the lungs and loss of eGFP+ cells, indicating that EC-Cav-1 phosphorylation may be required to development of Sch-PAH. Conclusions: Our data suggest that S. mansoni -induced pY14Cav-1 is associated to expression of the anti-apoptotic c-IAP2 protein, which may be critical for prolonged survival of a pathogenic EC phenotype during the development of Sch-PAH.