Project description:We introduce a novel in vitro platform that could simulate key native pulmonary vascular phenotypes and functions, and shows the potential of using the bioengineered whole organ as a platform for disease modeling. Since it is becoming clear that vascular endothelium and the coagulation cascade are adversely affected in some COVID19 patients, such an engineered organ system may play an important role in dissecting disease mechanisms and treatments.
Project description:Hypoxia can induce vasoconstriction followed by vascular remodeling including hypertrophy and hyperplasia of pulmonary vascular smooth muscle and proliferation of endothelial cells. The goal of this project is to elucidate the genes involved in vascular remodeling following pulmonary hypertension. Total RNA was isolated from lungs of normoxic and hypoxic treated animals. Keywords: other
Project description:Vascular dysfunction and organ failure are two distinct, albeit highly interconnected clinical outcomes linked to morbidity and mortality in human sepsis. The mechanisms driving vascular and parenchymal damage are dynamic and display significant molecular crosstalk between organs and tissues. Therefore, assessing their individual contribution to disease progression is technically challenging. Here, we hypothesize that dysregulated vascular responses predispose the organism to organ failure. To address this hypothesis, we have evaluated four major organs in a murine model of S. aureus sepsis by combining in vivo labeling of the endothelial proteome, data-independent acquisition (DIA) mass spectrometry, and an integrative computational pipeline. The data reveal, with unprecedented depth and throughput, that a septic insult evokes organ-specific proteome responses that are highly compartmentalized, synchronously coordinated, and significantly correlated with the progression of the disease. This includes abundant vascular shedding, dysregulation of the intrinsic pathway of coagulation, compartmentalization of the acute phase-response, and abundant upregulation of glycocalyx components. Vascular proteome changes were also found to precede bacterial invasion and leukocyte infiltration into the organs, as well as to precede changes in various well-established cellular and biochemical correlates of systemic coagulopathy and tissue dysfunction. Importantly, our data suggests a potential role for the vascular proteome as a determinant of the susceptibility of the organs to undergo failure during sepsis.
Project description:Early postnatal life is considered as a critical time window for determination of long-term metabolic states and organ functions. Extrauterine growth restriction (EUGR) causes the development of adult onset chronic diseases, including pulmonary arterial hypertension (PAH). However, the effects of nutritional disadvantages during early postnatal period on pulmonary vascular consequences in later life are not fully understood. Our study was designed to test whether epigentic dysregulation mediates the cellular memory of this early postnatal event. To test this hypothesis, we isolated pulmonary vascular endothelial cells (PVEC) by magnetic-activated cell sorting (MACS) from EUGR and control rats. A postnatal insult, nutritional restriction-induced EUGR caused development of an increased pulmonary artery pressure at 9-week of age in male rats. MeDIP-chip (Methyl-DNA immune precipitation chip), genome-scale mapping studies to search for differentially methylated loci between control and EUGR rats revealed significant difference in cytosine methylation between EUGR and control rats. We validated candidate dysregulated loci with quantitative assays of cytosine methylation and gene expressions. EUGR changes cytosine methylation at ~500 loci in male rats at 9 weeks of age, preceding the development of PAH and these represent candidate loci for mediating the pathogenesis of pulmonary vascular disease that occurs later in life. These results demonstrate that epigenetic dysregulation is a strong mechanism for propagating the cellular memory of early postnatal events, causing changes in expression of genes and long term susceptibility to PAH, and further providing a new insight into prevention and treatment of EUGR-related PAH. MeDIP together with microarray analysis demonstrated that significant differences in cytosine methylation between EUGR and control rats. Comparison of EUGR(n=3) vs Control (n=3) male rats' pulmonary vascular endothelial cells in 9-week age old rats
Project description:IL-4-mediated pro-inflammatory vascular responses have been implicated in the pathogenesis of chronic cardiopulmonary diseases. Our results show that hypoxia-induced collagen synthesis and early recruitment of inflammatory cells are significantly less in the lungs of IL-4 knockout (KO) mice than in those of wild-type mice. In addition, we found that IL-4 significantly increased pro-inflammatory genes in primary pulmonary microvascular endothelial cells. This study was designed to identify the gene expression profile of IL-4-dependent pulmonary vascular inflammation induced by hypoxia.
Project description:Hypoxia can induce vasoconstriction followed by vascular remodeling including hypertrophy and hyperplasia of pulmonary vascular smooth muscle and proliferation of endothelial cells. The goal of this project is to elucidate the genes involved in vascular remodeling following pulmonary hypertension. Total RNA was isolated from lungs of normoxic and hypoxic treated animals.
Project description:Off-the shelf small diameter vascular grafts are an attractive alternative to eliminate the need and shortcomings of autologous tissue for vascular grafting. Bovine saphenous vein (SV) extracellular matrix (ECM) scaffolds from are potentially ideal small diameter vascular grafts, due to their inherit architecture and signaling molecules capable of driving proper cell behavior and regeneration. However, harnessing this potential is predicated on the ability of the scaffold generation technique to maintain the delicate structure, composition and associated function of native vascular ECM. Previous decellularization methods have been uniformly demonstrated to distupt the delicate basement membrane (BM) components of native vascular ECM. Here we demonstrate bovine SV ECM scaffolds generated using the novel antigen removal (AR) approach results in retention of native BM protein composition (e.g., Collagen IV and laminin), structure and cell modulatory function. Presence of BM proteins in AR vascular ECM scaffolds increases endothelial cell migration and proliferation, appropriate formation of adherence junction and apicobasal polarization, increased secretion of nitric oxide, and modulates endothelial cell quiescence. We conclude that presence of intact native vascular BM in AR SV ECM scaffolds modulate human endothelial cell behaviors which are essential for vessel homeostasis.