Pharmacological Gq inhibition induces strong pulmonary vasorelaxation and reverses pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is a life-threatening disease with limited survival. Herein, we propose the pharmacological inhibition of Gq proteins as a novel concept to counteract pulmonary vasoconstriction and proliferation/migration of pulmonary artery smooth muscle cells (PASMCs) in PAH. We demonstrate that the specific pan-Gq inhibitor FR900359 (FR) induced a strong vasorelaxation in large and small pulmonary arteries in mouse, pig, and human subjects ex vivo.

Site-specific genetic and functional signatures of aortic endothelial cells at aneurysm predilection sites in healthy and AngII ApoE mice.

Aortic aneurysm is characterized by a pathological dilation at specific predilection sites of the vessel and potentially results in life-threatening vascular rupture. Herein, we established a modified "Häutchen method" for the local isolation of endothelial cells (ECs) from mouse aorta to analyze their spatial heterogeneity and potential role in site-specific disease development. When we compared ECs from aneurysm predilection sites of healthy mice with adjacent control segments we found regulation of genes related to extracellular matrix remodeling, angiogenesis and inflammation, all pathways playing a critical role in aneurysm development.

Forward programming of human induced pluripotent stem cells via the ETS variant transcription factor 2: rapid, reproducible, and cost-effective generation of highly enriched, functional endothelial cells.

Aims: Endothelial cell (EC) dysfunction plays a key role in the initiation and progression of cardiovascular disease. However, studying these disorders in ECs from patients is challenging; hence, the use of human induced pluripotent stem cells (hiPSCs) and their in vitro differentiation into ECs represents a very promising approach. Still, the generation of hiPSC-derived ECs (hECs) remains demanding as a cocktail of growth factors and an intermediate purification step are required for hEC enrichment.

Combined use of magnetic microbeads for endothelial cell isolation and enhanced cell engraftment in myocardial repair.

The regenerative potential of the heart after injury is limited. Therefore, cell replacement strategies have been developed. However, the engraftment of transplanted cells in the myocardium is very inefficient.

Inhibition of Vascular Growth by Modulation of the Anandamide/Fatty Acid Amide Hydrolase Axis.

Objective: Pathological angiogenesis is a hallmark of various diseases characterized by local hypoxia and inflammation. These disorders can be treated with inhibitors of angiogenesis, but current compounds display a variety of side effects and lose efficacy over time. This makes the identification of novel signaling pathways and pharmacological targets involved in angiogenesis a top priority.

Local anti-angiogenic therapy by magnet-assisted downregulation of SHP2 phosphatase.

Anti-angiogenic therapies are promising options for diseases with enhanced vessel formation such as tumors or retinopathies. In most cases, a site-specific local effect on vessel growth is required, while the current focus on systemic distribution of angiogenesis inhibitors may cause severe unwanted side-effects. Therefore, in the current study we have developed an approach for the local inhibition of vascularization, using complexes of lentivirus and magnetic nanoparticles in combination with magnetic fields.

PECAM/eGFP transgenic mice for monitoring of angiogenesis in health and disease.

For the monitoring of vascular growth as well as adaptive or therapeutic (re)vascularization endothelial-specific reporter mouse models are valuable tools. However, currently available mouse models have limitations, because not all endothelial cells express the reporter in all developmental stages. We have generated PECAM/eGFP embryonic stem (ES) cell and mouse lines where the reporter gene labels PECAM endothelial cells and vessels with high specificity.

In Vivo Labeling by CD73 Marks Multipotent Stromal Cells and Highlights Endothelial Heterogeneity in the Bone Marrow Niche.

Despite much work studying ex vivo multipotent stromal cells (MSCs), the identity and characteristics of MSCs in vivo are not well defined. Here, we generated a CD73-EGFP reporter mouse to address these questions and found EGFP MSCs in various organs. In vivo, EGFP mesenchymal cells were observed in fetal and adult bones at proliferative ossification sites, while in solid organs EGFP cells exhibited a perivascular distribution pattern.

Improved heart repair upon myocardial infarction: Combination of magnetic nanoparticles and tailored magnets strongly increases engraftment of myocytes.

Cell replacement in the heart is considered a promising strategy for the treatment of post-infarct heart failure. Direct intramyocardial injection of cells proved to be the most effective application route, however, engraftment rates are very low (<5%) strongly hampering its efficacy. Herein we combine magnetic nanoparticle (MNP) loading of EGFP labeled embryonic cardiomyocytes (eCM) and embryonic stem cell-derived cardiomyocytes (ES-CM) with application of custom designed magnets to enhance their short and long-term engraftment.

Improvement of vascular function by magnetic nanoparticle-assisted circumferential gene transfer into the native endothelium.

Gene therapy is a promising approach for chronic disorders that require continuous treatment such as cardiovascular disease. Overexpression of vasoprotective genes has generated encouraging results in animal models, but not in clinical trials. One major problem in humans is the delivery of sufficient amounts of genetic vectors to the endothelium which is impeded by blood flow, whereas prolonged stop-flow conditions impose the risk of ischemia.

Vascular Repair by Circumferential Cell Therapy Using Magnetic Nanoparticles and Tailored Magnets.

Cardiovascular disease is often caused by endothelial cell (EC) dysfunction and atherosclerotic plaque formation at predilection sites. Also surgical procedures of plaque removal cause irreversible damage to the EC layer, inducing impairment of vascular function and restenosis. In the current study we have examined a potentially curative approach by radially symmetric re-endothelialization of vessels after their mechanical denudation.

Transduction of murine embryonic stem cells by magnetic nanoparticle-assisted lentiviral gene transfer.

Genetic modification of embryonic stem (ES) cells is a valuable technique when combined with cell replacement strategies. Obtaining stable transgene expression and low-cytotoxicity lentiviral transduction of ES cells is advantageous. It has been shown that the efficiency of transfection and transduction approaches can be increased by magnetic nanoparticles (MNPs).

Identification of magnetic nanoparticles for combined positioning and lentiviral transduction of endothelial cells.

Purpose: The combination of magnetic nanoparticles (MNPs) with a magnetic field is a powerful approach to enable cell positioning and/or local gene therapy. Because physical requirements for MNPs differ between these two applications we have explored whether the use of different MNPs can provide site-specific positioning combined with efficient viral transduction of endothelial cells (ECs).

Methods: A variety of MNPs was screened for magnetic cell labeling and lentivirus binding.