Biochemical, biophysical, and immunological characterization of respiratory secretions in severe SARS-CoV-2 infections.

Thick, viscous respiratory secretions are a major pathogenic feature of COVID-19, but the composition and physical properties of these secretions are poorly understood. We characterized the composition and rheological properties (i.e.

Biochemical, Biophysical, and Immunological Characterization of Respiratory Secretions in Severe SARS-CoV-2 (COVID-19) Infections.

Thick, viscous respiratory secretions are a major pathogenic feature of COVID-19 disease, but the composition and physical properties of these secretions are poorly understood. We characterized the composition and rheological properties (i.e.

Detection of Glycosaminoglycans in Pancreatic Islets and Lymphoid Tissues.

In this chapter, we describe the detection of the glycosaminoglycans hyaluronan and heparan sulfate in pancreatic islets and lymphoid tissues. The identification of hyaluronan in tissues is achieved by utilizing a highly specific hyaluronan binding protein (HABP) probe that interacts with hyaluronan in tissue sections. The HABP probe is prepared by enzymatic digestion of the chondroitin sulfate proteoglycan aggrecan which is present in bovine nasal cartilage and is then biotinylated in the presence of bound hyaluronan and the link protein.

Hyaluronan deposition in islets may precede and direct the location of islet immune-cell infiltrates.

Aims/hypothesis: Substantial deposition of the extracellular matrix component hyaluronan (HA) is characteristic of insulitis in overt type 1 diabetes. We investigated whether HA accumulation is detectable in islets early in disease pathogenesis and how this affects the development of insulitis and beta cell mass.

Methods: Pancreas tissue from 15 non-diabetic organ donors who were positive for islet autoantibodies (aAbs) and from 14 similarly aged aAb control donors were examined for the amount of islet HA staining and the presence of insulitis.

The biochemistry and immunohistochemistry of versican.

Versican is a chondroitin sulfate proteoglycan found in the extracellular matrix that is important for changes in cell phenotype associated with development and disease. Versican has been shown to be involved in cardiovascular disorders, as well as lung disease and fibrosis, inflammatory bowel disease, cancer, and several other diseases that have an inflammatory component. Versican was first identified as a fibroblast proteoglycan and forms large multimolecular complexes with hyaluronan and other components of the provisional matrix during wound healing and inflammation.

Hyaluronan content governs tissue stiffness in pancreatic islet inflammation.

We have identified a novel role for hyaluronan (HA), an extracellular matrix polymer, in governing the mechanical properties of inflamed tissues. We recently reported that insulitis in type 1 diabetes of mice and humans is preceded by intraislet accumulation of HA, a highly hygroscopic polymer. Using the double transgenic DO11.

Versican Deficiency Significantly Reduces Lung Inflammatory Response Induced by Polyinosine-Polycytidylic Acid Stimulation.

Viral infection is an exacerbating factor contributing to chronic airway diseases, such as asthma, via mechanisms that are still unclear. Polyinosine-polycytidylic acid (poly(I:C)), a Toll-like receptor 3 (TLR3) agonist used as a mimetic to study viral infection, has been shown to elicit inflammatory responses in lungs and to exacerbate pulmonary allergic reactions in animal models. Previously, we have shown that poly(I:C) stimulates lung fibroblasts to accumulate an extracellular matrix (ECM), enriched in hyaluronan (HA) and its binding partner versican, which promotes monocyte adhesion.

Versican accumulates in vascular lesions in pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a lethal condition for which there is no effective curative pharmacotherapy. PAH is characterized by vasoconstriction, wall thickening of pulmonary arteries, and increased vascular resistance. Versican is a chondroitin sulfate proteoglycan in the vascular extracellular matrix that accumulates following vascular injury and promotes smooth-muscle cell proliferation in systemic arteries.

Inhibition of hyaluronan synthesis restores immune tolerance during autoimmune insulitis.

We recently reported that abundant deposits of the extracellular matrix polysaccharide hyaluronan (HA) are characteristic of autoimmune insulitis in patients with type 1 diabetes (T1D), but the relevance of these deposits to disease was unclear. Here, we have demonstrated that HA is critical for the pathogenesis of autoimmune diabetes. Using the DO11.

Hyaluronan: A Mediator of Islet Dysfunction and Destruction in Diabetes?

Hyaluronan (HA) is an extracellular matrix (ECM) component that is present in mouse and human islet ECM. HA is localized in peri-islet and intra-islet regions adjacent to microvessels. HA normally exists in a high molecular weight form, which is anti-inflammatory.

The detection of glycosaminoglycans in pancreatic islets and lymphoid tissues.

In this chapter, we describe the detection of the glycosaminoglycans hyaluronan and heparan sulfate in pancreatic islets and lymphoid tissues. The identification of hyaluronan in tissues is achieved by utilizing a highly specific hyaluronan binding protein (HABP) probe that interacts with hyaluronan in tissue sections. The HABP probe is prepared by enzymatic digestion of the chondroitin sulfate proteoglycan aggrecan which is present in bovine nasal cartilage, and is then biotinylated in the presence of bound hyaluronan and the link protein.

Reprint of: A rapid increase in macrophage-derived versican and hyaluronan in infectious lung disease.

The goals of this study were to characterize the changes in chondroitin sulfate proteoglycans and hyaluronan in lungs in acute response to gram-negative bacterial infection and to identify cellular components responsible for these changes. Mice were treated with intratracheal (IT) live Escherichia coli, E. coli lipopolysaccharide (LPS), or PBS.

Hyaluronan and hyaluronan-binding proteins accumulate in both human type 1 diabetic islets and lymphoid tissues and associate with inflammatory cells in insulitis.

Hyaluronan (HA) is an extracellular matrix glycosaminoglycan that is present in pancreatic islets, but little is known about its involvement in the development of human type 1 diabetes (T1D). We have evaluated whether pancreatic islets and lymphoid tissues of T1D and nondiabetic organ donors differ in the amount and distribution of HA and HA-binding proteins (hyaladherins), such as inter-α-inhibitor (IαI), versican, and tumor necrosis factor-stimulated gene-6 (TSG-6). HA was dramatically increased both within the islet and outside the islet endocrine cells, juxtaposed to islet microvessels in T1D.

A rapid increase in macrophage-derived versican and hyaluronan in infectious lung disease.

The goals of this study were to characterize the changes in chondroitin sulfate proteoglycans and hyaluronan in lungs in acute response to gram-negative bacterial infection and to identify cellular components responsible for these changes. Mice were treated with intratracheal (IT) live Escherichia coli, E. coli lipopolysaccharide (LPS), or PBS.

Hyaluronan and hyaluronan binding proteins are normal components of mouse pancreatic islets and are differentially expressed by islet endocrine cell types.

The pancreatic islet comprises endocrine, vascular, and neuronal cells. Signaling among these cell types is critical for islet function. The extracellular matrix (ECM) is a key regulator of cell-cell signals, and while some islet ECM components have been identified, much remains unknown regarding its composition.

Proteolytic cleavage of versican and involvement of ADAMTS-1 in VEGF-A/VPF-induced pathological angiogenesis.

Malignant tumors and chronic inflammatory diseases induce angiogenesis by overexpressing vascular endothelial growth factor A (VEGF-A/VPF). VEGF-A-induced pathological angiogenesis can be mimicked in immunoincompetent mice with an adenoviral vector expressing VEGF-A(164) (Ad-VEGF-A(164)). The initial step is generation of greatly enlarged "mother" vessels (MV) from preexisting normal venules by a process involving degradation of their rigid basement membranes.

Synthesis and organization of hyaluronan and versican by embryonic stem cells undergoing embryoid body differentiation.

Embryonic stem cells (ESCs) provide a convenient model to probe the molecular and cellular dynamics of developmental cell morphogenesis. ESC differentiation in vitro via embryoid bodies (EBs) recapitulates many aspects of early stages of development, including the epithelial-mesenchymal transition (EMT) of pluripotent cells into more differentiated progeny. Hyaluronan and versican are important extracellular mediators of EMT processes, yet the temporal expression and spatial distribution of these extracellular matrix (ECM) molecules during EB differentiation remains undefined.

Polyinosine-polycytidylic acid stimulates versican accumulation in the extracellular matrix promoting monocyte adhesion.

Viral infections are known to exacerbate asthma and other lung diseases in which chronic inflammatory processes are implicated, but the mechanism is not well understood. The viral mimetic, polyinosine-polycytidylic acid, causes accumulation of a versican- and hyaluronan-enriched extracellular matrix (ECM) by human lung fibroblasts with increased capacity for monocyte adhesion. The fivefold increase in versican retention in this ECM is due to altered compartmentalization, with decreased degradation of cell layer-associated versican, rather than an increase in total accumulation in the culture.

Cutaneous chronic graft-versus-host disease does not have the abnormal endothelial phenotype or vascular rarefaction characteristic of systemic sclerosis.

Background: The clinical and histologic appearance of fibrosis in cutaneous lesions in chronic graft-versus -host disease (c-GVHD) resembles the appearance of fibrosis in scleroderma (SSc). Recent studies identified distinctive structural changes in the superficial dermal microvasculature and matrix of SSc skin. We compared the dermal microvasculature in human c-GVHD to SSc to determine if c-GVHD is a suitable model for SSc.

Organization of hyaluronan and versican in the extracellular matrix of human fibroblasts treated with the viral mimetic poly I:C.

We have examined structural details of hyaluronan- and versican-rich pericellular matrices in human lung fibroblasts, as well as fixation effects after treatment with the viral mimetic, poly I:C. Lateral aggregation of hyaluronan chains was promoted by acid-ethanol-formalin fixation compared with a network appearance with formalin alone. However, hyaluronidase-sensitive cable structures were seen in live cells, suggesting that they are not a fixation artifact.

Retrovirally mediated overexpression of glycosaminoglycan-deficient biglycan in arterial smooth muscle cells induces tropoelastin synthesis and elastic fiber formation in vitro and in neointimae after vascular injury.

Galactosamine-containing glycosaminoglycans (GAGs), such as the chondroitin sulfate chains of the proteoglycan versican, have been shown to inhibit elastogenesis. Another proteoglycan that may influence elastogenesis is biglycan, which possesses two GAG chains. To assess the importance of these chains on elastogenesis in blood vessels, rat aortic smooth muscle cells were transduced with a GAG-deficient biglycan cDNA-containing retroviral vector (LmBSN).

Hyaluronan accumulation is elevated in cultures of low density lipoprotein receptor-deficient cells and is altered by manipulation of cell cholesterol content.

The extracellular matrix molecule hyaluronan (HA) accumulates in human atherosclerotic lesions. Yet the reasons for this accumulation have not been adequately addressed. Because abnormalities in lipid metabolism promote atherosclerosis, we have asked whether disrupted cholesterol homeostasis alters HA accumulation in low density lipoprotein receptor-deficient cell cultures.

Decorin synthesized by arterial smooth muscle cells is retained in fibrin gels and modulates fibrin contraction.

Fibrin serves as a provisional extracellular matrix (ECM) for arterial smooth muscle cells (ASMC) after vascular injury, yet little is known about the effect of fibrin on ECM remodeling by these cells. To address this question, monkey ASMC were grown on fibrin gels and tissue culture (TC) plastic, and proteoglycan synthesis and accumulation were assessed by radiolabeling. Initial rates of (35)S-sulfate incorporation into proteoglycans were identical for both groups, but increased proteoglycan accumulation was observed in cultures grown for 48 h on fibrin.

Sirolimus blocks the accumulation of hyaluronan (HA) by arterial smooth muscle cells and reduces monocyte adhesion to the ECM.

Sirolimus (SRL), an inhibitor of human arterial smooth muscle cell (ASMC) proliferation and migration, prevents in-stent restenosis (ISR). Little is known about the effect of SRL on the extracellular matrix (ECM) component, hyaluronan, a key macromolecule in neointimal hyperplasia and inflammation. In this study, we investigated SRL regulation of the synthesis of hyaluronan by cultured human ASMC and the effect of SRL on hyaluronan mediated monocyte adhesion to the ECM.

Inhibition of cell proliferation by mitomycin C incorporated into P(HEMA) hydrogels.

Objectives: The technique of mitomycin C (MMC) drug delivery and its application in glaucoma surgery are not standardized with resultant inconsistencies in the results. Also, one time application of MMC does not seem to have the same efficacy after glaucoma drainage device surgeries compared with trabeculectomies. This preliminary study examined the efficacy of a slow release form of MMC for its ability to inhibit cell proliferation in vitro.