Biology subjects

Bogaard, H. J.

Publications and source records attributed to Bogaard, H. J..

7 recordsLinked to original sources

bioRxiv2025

BMP9 regulates the endothelial secretome to drive pulmonary hypertension

BMP9, a pleiotropic growth factor cytokine that regulates endothelial function, is implicated in the pathogenesis of pulmonary arterial hypertension (PAH). Loss-of-function mutations in GDF2 are found in heritable PAH, suggesting its function as an endothelial quiescence factor, while agonizing or antagonizing BMP9 signaling are both reported to ameliorate experimental pulmonary hypertension (PH). This study sought to resolve the contribution of BMP9 to pulmonary vascular disease and its status as a potential therapeutic target. The function of BMP9 in experimental PH was interrogated using recombinant BMP9, BMP9/BMP10 ligand trap ALK1-Fc, two anti-BMP9 neutralizing antibodies, and the activin/GDF/BMP ligand trap ACTRIIA-Fc (a.k.a., sotatercept). Disulfide-linked, prodomain complexed BMP9 was not protective in SUGEN-hypoxia or monocrotaline-induced PH models, in contrast to previous studies using incompletely disulfide-linked BMP9. In comparison, selective and non-selective BMP9 antagonism exerted prophylactic and therapeutic effects across PH models. Anti-BMP9 and ACTRIIA-Fc had comparable impact on hemodynamics, RV hypertrophy, and vascular remodeling, while single nucleus RNA-Seq revealed similar inhibition of SMAD1/5 and SMAD2/3 transcriptional activity, and highly overlapping DEGs, particularly in the endothelial compartment (r=0.83, p=2.54e-43, Spearman), suggesting overlap of mechanism in targeting BMP9. A multi-omic approach using lung tissues from human PAH, experimental models of pulmonary hypertension, and transcriptomic analysis of pulmonary microvascular endothelial cells from PAH patients revealed that BMP9 is critical for regulating several endothelial gene products that are overexpressed in human and experimental disease and implicated in disease pathogenesis including CXCL12, PDGF-BB, EDN1, COL18A1, and IGFBP4, and are inhibited by administering anti-BMP9 neutralizing antibodies or ligand traps. Co-culture studies revealed paracrine effects of BMP9-stimulated PMVEC on pulmonary arterial smooth muscle cell (PASMC) phenotypic plasticity, which could be attributed in large part to endothelial-derived CXCL12. In summary, endothelial BMP9 signaling is a key coordinator of vasoactive endothelial gene products that modulate PASMC phenotype and appears to be a shared target of anti-BMP9 and ACTRIIA-Fc. Selective targeting of endothelial BMP9 angiogenic signaling represents a potential therapeutic strategy for human PAH. One sentence summaryInhbiition of BMP9 signaling via different selective and non-selective strategies, including ACTRIIA-Fc/sotatercept, attenuates endothelial expression of vasoactive secreted factors that drive pulmonary vascular remodeling.

physiology↗

bioRxiv2024

Role of Forkhead box F1 in the Pathobiology of Pulmonary Arterial Hypertension

RationaleApproximately 80% of patients with non-familial pulmonary arterial hypertension (PAH) lack identifiable pathogenic genetic variants. While most genetic studies of PAH have focused on predicted loss-of-function variants, recent approaches have identified ultra-rare missense variants associated with the disease. FOXF1 encodes a highly conserved transcription factor, essential for angiogenesis and vasculogenesis in human and mouse lungs. ObjectivesWe identified a rare FOXF1 missense coding variant in two unrelated probands with PAH. FOXF1 is an evolutionarily conserved transcription factor required for lung vascular development and vascular integrity. Our aims were to determine the frequency of FOXF1 variants in larger PAH cohorts compared to the general population, study FOXF1 expression in explanted lung tissue from PAH patients versus control (failed-donor) lungs, and define potential downstream targets linked to PAH development. MethodsThree independent, international, multicenter cohorts were analyzed to evaluate the frequency of FOXF1 rare variants. Various composite prediction models assessed the deleteriousness of individual variants. Bulk RNA sequencing datasets from human explanted lung tissues were compared to failed-donor controls to determine FOXF1 expression. Bioinformatic tools identified putative FOXF1 binding targets, which were orthogonally validated using mouse ChIP-seq datasets. Measurements and Main ResultsSeven novel or ultra-rare missense coding variants were identified across three patient cohorts in different regions of the FOXF1 gene, including the DNA binding domain. FOXF1 expression was dysregulated in PAH lungs, correlating with disease severity. Histological analysis showed heterogeneous FOXF1 expression, with the lowest levels in phenotypically abnormal endothelial cells within complex vascular lesions in PAH samples. A hybrid bioinformatic approach identified FOXF1 downstream targets potentially involved in PAH pathogenesis, including BMPR2. ConclusionsLarge genomic and transcriptomic datasets suggest that decreased FOXF1 expression or predicted dysfunction is associated with PAH.

genomics↗

bioRxiv2022

Identification of new drugs to counteract anti-spike IgG-induced hyperinflammation in severe COVID-19

Previously, we and others have shown that SARS-CoV-2 spike-specific IgG antibodies play a major role in disease severity in COVID-19 by triggering macrophage hyperactivation, disrupting endothelial barrier integrity, and inducing thrombus formation. This hyper-inflammation is dependent on high levels of anti-spike IgG with aberrant Fc tail glycosylation, leading to Fc{gamma} receptor hyper-activation. For development of immune-regulatory therapeutics, drug specificity is crucial to counteract excessive inflammation while simultaneously minimizing inhibition of antiviral immunity. We here developed an in vitro activation assay to screen for small molecule drugs that specifically counteract antibody-induced pathology. We identified that anti-spike induced inflammation is specifically blocked by small molecule inhibitors against SYK and PI3K. We identified SYK inhibitor entospletinib as the most promising candidate drug, which also counteracted anti-spike-induced endothelial dysfunction and thrombus formation. Moreover, entospletinib blocked inflammation by different SARS-CoV-2 variants of concern. Combined, these data identify entospletinib as a promising treatment for severe COVID-19. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=136 SRC="FIGDIR/small/521247v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@edb3d5org.highwire.dtl.DTLVardef@1b99dd8org.highwire.dtl.DTLVardef@129ec7corg.highwire.dtl.DTLVardef@165000f_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2020

Distinct cellular immune profiles in the airways and blood of critically ill patients with COVID 19

Our understanding of the coronavirus disease-19 (COVID-19) immune response is almost exclusively derived from studies that examined blood. To gain insight in the pulmonary immune response we analysed BALF samples and paired blood samples from 17 severe COVID-19 patients. Macrophages and T cells were the most abundant cells in BALF. In the lungs, both CD4 and CD8 T cells were predominantly effector memory cells and expressed higher levels of the exhaustion marker PD-1 than in peripheral blood. Prolonged ICU stay associated with a reduced proportion of activated T cells in peripheral blood and even more so in BALF. T cell activation in blood, but not in BALF, was higher in fatal COVID-19 cases. Increased levels of inflammatory mediators were more pronounced in BALF than in plasma. In conclusion, the bronchoalveolar immune response in COVID-19 has a unique local profile that strongly differs from the immune profile in peripheral blood. SummaryThe bronchoalveolar immune response in severe COVID-19 strongly differs from the peripheral blood immune profile. Fatal COVID-19 associated with T cell activation blood, but not in BALF.

immunology↗

bioRxiv2020

Anti-SARS-CoV-2 IgG from severely ill COVID-19 patients promotes macrophage hyper-inflammatory responses

For yet unknown reasons, severely ill COVID-19 patients often become critically ill around the time of activation of adaptive immunity. Here, we show that anti-Spike IgG from serum of severely ill COVID-19 patients induces a hyper-inflammatory response by human macrophages, which subsequently breaks pulmonary endothelial barrier integrity and induces microvascular thrombosis. The excessive inflammatory capacity of this anti-Spike IgG is related to glycosylation changes in the IgG Fc tail. Moreover, the hyper-inflammatory response induced by anti-Spike IgG can be specifically counteracted in vitro by use of the active component of fostamatinib, an FDA- and EMA-approved therapeutic small molecule inhibitor of Syk. One sentence summaryAnti-Spike IgG promotes hyper-inflammation.

immunology↗

bioRxiv2019

Krüppel-like factor 2- induced microRNAs: implications for treatment of pulmonary hypertension

Flow-activated transcription factor Kruppel-like factor 2 (KLF2) signaling is compromised in pulmonary arterial hypertension (PAH). We aimed to identify KLF2-induced endothelium-protective exosomal microRNAs of potential therapeutic significance.\n\nEight exosomal microRNAs elevated by KLF2 but reduced in PAH were transfected into human pulmonary artery endothelial cells. Of these, only miR-181a-5p and miR-324-5p had anti-apoptotic, anti-inflammatory and anti-proliferative effect on endothelial cells and reduced proliferation of vascular smooth muscle cells in vitro. RNA sequencing of miRNA-transfected HPAECs revealed reduced expression of multiple genes implicated in vascular remodelling, including ETS-1, NOTCH4, ACTA2, TNF-, IL-1, MMP10, MAPK and NFATC2. KLF2, miR-181a-5p and miR-324-5p were reduced, while their target genes were elevated in blood-derived endothelial colony forming cells and lung tissues from idiopathic and heritable PAH patients with disabling KLF2 mutation and Sugen/hypoxia mice. Supplementation of miR-181a-5p and miR-324-5p or silencing of their target genes attenuated proliferative and angiogenic responses in endothelial cells from idiopathic PAH and prevented development of pulmonary hypertension in Sugen/hypoxia mice.\n\nThis study highlights potential therapeutic role of KLF2-induced exosomal microRNAs in PAH.

cell biology↗

bioRxiv2017

Novel causative genes for heritable pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a rare disorder with a poor prognosis. Deleterious variation within components of the transforming growth factor-{beta} pathway, particularly the bone morphogenetic protein type 2 receptor (BMPR2), underlie most heritable forms of PAH. Since the missing heritability likely involves genetic variation confined to small numbers of cases, we performed whole genome sequencing in 1038 PAH index cases and 6385 PAH-negative control subjects. Case-control analyses revealed significant overrepresentation of rare variants in novel genes, namely ATP13A3, AQP1 and SOX17, and provided independent validation of a critical role for GDF2 in PAH. We provide evidence for familial segregation of mutations in SOX17 and AQP1 with PAH. Mutations in GDF2, encoding a BMPR2 ligand, led to reduced secretion from transfected cells. In addition, we identified pathogenic mutations in the majority of previously reported PAH genes, and provide evidence for further putative genes. Taken together these findings provide new insights into the molecular basis of PAH and indicate unexplored pathways for therapeutic intervention.

genetics↗