Enhancer of Zeste Homolog 2 Induces Pulmonary Artery Smooth Muscle Cell Proliferation

Pulmonary Arterial Hypertension (PAH) is a progressively devastating disease characterized by excessive proliferation of the Pulmonary Arterial Smooth Muscle Cells (PASMCs). Studies suggest that PAH and cancers share an apoptosis-resistant state featuring excessive cell proliferation. The proliferation of cancer cells is mediated by increased expression of Enhancer of Zeste Homolog 2 (EZH2), a mammalian histone methyltransferase that contributes to the epigenetic silencing of target genes. However, the role of EZH2 in PAH has not been studied. In this study, it is hypothesized that EZH2 could play a role in the proliferation of PASMCs.In the present study, the expression patterns of EZH2 were investigated in normal and hypertensive mouse PASMCs. The effects of EZH2 overexpression on the proliferation of human PASMCs were tested. PASMCs were transfected with EZH2 or GFP using nucleofector system. After transfection, the cells were incubated for 48 hours at 37°C. Proliferation and cell cycle analysis were performed using flow cytometry. Apoptosis of PASMCs was determined using annexin V staining and cell migration was tested by wound healing assay.EZH2 protein expression in mouse PASMCs were correlated with an increase in right ventricular systolic pressure and Right Ventricular Hypertrophy (RVH). The overexpression of EZH2 in human PASMCs enhances proliferation, migration, and decrease in the rate of apoptosis when compared to GFP-transfected cells. In the G2/M phase of the EZH2 transfected cells, there was a 3.5 fold increase in proliferation, while there was a significant decrease in the rate of apoptosis of PASMCs, when compared to control.These findings suggest that EZH2 plays a role in the migration and proliferation of PASMCs, which is a major hallmark in PAH. It also suggests that EZH2 could play a role in the development of PAH and can serve as a potential target for new therapies for PAH

Safety, tolerability, pharmacokinetics and pharmacodynamic effects of desmoglein 3 peptide-coupled tolerizing nanoparticles in pemphigus

Background Pemphigus vulgaris (PV) is a CD4+ T-cell-dependent autoantibody-mediated blistering disease associated with human leucocyte antigen (HLA) class II molecules. IgG autoantibodies against the primary autoantigen desmoglein 3 (Dsg3), a desmosomal adhesion protein on epidermal keratinocytes, cause loss of epidermal cell adhesion. Objectives To assess the clinical applicability of an innovative nanoparticle platform for the induction of immune tolerance exploiting the natural tolerance potential of liver sinusoidal endothelial cells. An open-label first-in-human study was conducted with TPM203, a mixture of four nanoparticle-coupled immunodominant Dsg3 T-cell peptides. Methods The efficacy and mechanism of action of TPM203 were first tested in a humanized HLA-DRB1*0402-transgenic PV mouse model. In the clinical phase I trial, TPM203 was administered intravenously in patients with PV with no-to-moderate disease activity in single ascending and multiple doses (three doses of TPM203 two weeks apart). Primary endpoints included safety and tolerability. As a secondary endpoint, pharmacokinetics were assessed. Exploratory endpoints comprised changes in Dsg3-specific and bulk T- and B-cell frequencies, anti-Dsg3 IgG levels and autoantibody-induced keratinocyte dissociation. The trial was registered with EudraCT (2019-001727-12). Results In the PV mouse model, two administrations of TPM203 significantly reduced anti-Dsg3 IgG. On the cellular level, TPM203 led to a significant decrease in CD4+ T cells in the spleen, accompanied by increased frequencies of regulatory T (Treg) cells. In the clinical trial, the 17 patients with PV enrolled across single- and multiple-dose groups did not experience any serious or severe adverse events, or treatment-related PV worsening. Pharmacokinetics confirmed rapid TPM203 clearance from the circulation. Significant TPM203-induced modulations in bulk lymphocyte subsets included an increase in Treg cells, and reductions in T helper 17.1 and CD27+ memory B cells, when dose groups were combined for analysis. Dsg3-specific T cells were found to be significantly reduced at week 8 following single administration of TPM203. Anti-Dsg3 IgG levels trended downward in the three lower single ascending dose groups, while IgG-induced keratinocyte-dissociating capacity was significantly reduced after multiple doses. Conclusions Administered for the first time in humans, TPM203 was shown to be a safe and well-tolerated nanoparticle-based therapeutic approach with the potential to promote tolerance induction in PV, justifying further clinical development in this and other autoimmune diseases

Similarity-based web clip matching

The research areas of extraction and integration of web data aim at delivery of tools and methods to extract pieces of information from third-party web sites and then to integrate them into profiled, domain-specific, custom web pages. Existing solutions rely on specialized APIs or XPath querying tools and are therefore not easily accessible to non technical end users. In this paper we describe our new comprehensive, non-XPath integration platform which allows end users to extract web page fragments using a simple query-by-example approach and then to combine these fragments into custom, integrated web pages. We focus on our two novel similarity-based web clip matching algorithms: Attribute Weights Tree Matching and Edit Distance Tree Matching

Atherogenesis and plaque rupture, surface/interface-related phenomena

In atherogenesis, free oxygen radicals cause a lipid peroxidation of apoB100-containing lipoproteins in the blood, at the blood–endothelium-interface and in the subendothelial space. These lipoproteins easily aggregate, bind to their receptor heparan sulfate proteoglycan and calcify to arteriosclerotic nanoplaques (ternary complexes). Nanoplaque formation was measured by ellipsometry, both in vitro on an HS-PG coated hydrophobic silica surface and also in vivo on living human coronary endothelial cells, which had overgrown the silica surface. Reversely, we show with the same techniques that, in dependence on the degree of peroxidation and epitope in concern, oxLDL attacks its molecular receptor and thus can induce degradation of arteriosclerotic plaques and, in a combined action with inflammatory processes, even a plaque rupture. In order to delay or stop this process, cytokines circulating in the blood such as TNFα and TGFβ upregulate PML-NB especially in the vulnerable shoulder region of the plaque. PML-NB influences via two transcription factors, CIITA and NFκB, the collagen and proteoglycan synthesis both negatively and positively. We could prove that the purely negative effect of CIITA does not play any role, while the altogether positive effect of NFκB predominates. NFκB is inhibited with the help of the transcription mediator SMAD4 within this molecular feedback control circuit; simultaneously, NFκB inhibits the collagen and proteoglycan synthesis in the fibrous cap of the plaque. This double check (disinhibition) causes a stabilization of the fibrous cap through a specially strong collagen and proteoglycan production, which in addition is supported by circulating TGFβ. TGFβ furthers also calcification, so that fibrous cap tensile strength and resistance to shear stress are imparted. This way, a plaque rupture can possibly be averted

Morphometry of skeletal muscle capillaries: the relationship between capillary ultrastructure and ageing in humans.

AIM To determine whether the ultrastructure of the capillary system in human skeletal muscle changes during advancing senescence, we evaluated the compartmental and subcompartmental organization of capillaries from vastus lateralis muscle (VL) biopsies of 41 non-diseased persons aged 23-75 years. METHODS From each VL biopsy, 38-40 randomly selected capillaries were assessed by transmission electron microscopy and subsequent morphometry with a newly established tablet-based image analysis technique. RESULTS Quantification of the compartmental organization revealed most indicators of the capillary ultrastructure to be only non-significantly altered (P > 0.05) over age. However, the peri-capillary basement membrane (BM) was thicker in the older participants than in the younger ones (P ≤ 0.05). Regression analysis revealed a bipartite relationship between the two parameters: a homogenous slight increase in BM thickness up to the age of approximately 50 years was followed by a second phase with more scattered BM thickness values. In 44.5% of the capillary profiles, projections/filopodia of the pericytes (PCs) traversed the BM and invaded endothelial cells (ECs) visible as PC pegs in pale cytoplasm holes (EC sockets). Strikingly, PC pegs were often in proximity to the EC nucleus. In PC profiles, sockets were likewise detected in 14.2% of the capillaries. Within these PC sockets, cellular profiles were frequently seen, which could be assigned to EC filopodia, internal PC curling or PC-PC interactions. Quantification of the occurrence of peg-socket junctions revealed the proportions of empty EC sockets and empty PC sockets to increase (P ≤ 0.05) during ageing. CONCLUSION Our investigation demonstrates advancing senescence to be associated with increase in BM thickness and loss of EC and PC filopodia length in skeletal muscle capillaries