ILB® resolves inflammatory scarring and promotes functional tissue repair

Fibrotic disease is a major cause of mortality worldwide, with fibrosis arising from prolonged inflammation and aberrant extracellular matrix dynamics. Compromised cellular and tissue repair processes following injury, infection, metabolic dysfunction, autoimmune conditions and vascular diseases leave tissues susceptible to unresolved inflammation, fibrogenesis, loss of function and scarring. There has been limited clinical success with therapies for inflammatory and fibrotic diseases such that there remains a large unmet therapeutic need to restore normal tissue homoeostasis without detrimental side effects. We investigated the effects of a newly formulated low molecular weight dextran sulfate (LMW-DS), termed ILB®, to resolve inflammation and activate matrix remodelling in rodent and human disease models. We demonstrated modulation of the expression of multiple pro-inflammatory cytokines and chemokines in vitro together with scar resolution and improved matrix remodelling in vivo. Of particular relevance, we demonstrated that ILB® acts, in part, by downregulating transforming growth factor (TGF)β signalling genes and by altering gene expression relating to extracellular matrix dynamics, leading to tissue remodelling, reduced fibrosis and functional tissue regeneration. These observations indicate the potential of ILB® to alleviate fibrotic diseases.


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Life sciences study design
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We require information from authors about some types of materials, experimental systems and methods used in many studies. Here, indicate whether each material, system or method listed is relevant to your study. If you are not sure if a list item applies to your research, read the appropriate section before selecting a response. Rabbit anti-laminin antibody, Sigma, L393; https://www.sigmaaldrich.com/catalog/product/sigma/l9393?lang=en&region=GB Specificity of the anti-laminin antibody is determined by indirect immunofluorescent labeling of formalin-fixed, paraffin-embedded human or animal tissue sections, and by dot blot immunoassay. By indirect immunofluorescence the antibody demonstrates specific basement membrane staining of enzymatically unmasked human and animal tissue. In the dot blot immunoassay the rabbit antilaminin antibody reacts with laminin but not with fibronectin, vitronectin, collagen IV, or chondroitin sulfate types A, B, and C. The affinity isolated antibody to laminin will react with laminin of human, mammal, avian, reptilian, and amphibian sources. The antibody shows no cross-reaction with collagen type IV, fibronectin or chondroitin sulfate types A, B, and C using a dot blot immunoassay. Rabbit Anti-Laminin antibody may be used in immunohistochemistry for marking blood vessel walls in different species, classification of various disease processes involving basement membranes, identification of the origin of human tumors and their classification, and for distinguishing between non-invasive and invasive lesions. The antibody may be used to monitor levels of laminin in biological fluids and for experimental production of basement membrane lesions in vivo. A working dilution of at least 1:1,000 was determined by a dot blot immunoassay using laminin at 50 ng per dot. A working dilution of at least 1:25 was determined by indirect immunohistology using formalin-fixed, paraffin-embedded human and animal tissues.

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April 2020 Specificity The anti-fibronctin antibody shows no cross-reaction with laminin, vitronectin, collagen type IV, or chondroitin sulfate types A, B and C using a dot blot immunoassay. The asntiserum is produced in rabbit using purified human fibronectin as the immunogen. Affinity isolated antibody is obtained from antiserum by immunospecific purification which removes essentially all rabbit serum proteins, including immunoglobulins, which do not specifically bind to human fibronectin. The antiserum is determined to be immunospecific for human fibronectin by immunofluorescent labeling of human fibroblast cell cultures, ELISA and immunoblotting. In immunoblotting, a specific band of fibronectin at 220 kDa is observed (another band at 94 kDa may be also be present) using human fibronectin. When used in immunoelectrophoresis, the antibody shows 1-2 arcs of precipitation versus normal human plasma. This product may be used for immunohistochemical localization of fibronectin in normal, inflamed and neoplastic tissues, for detection of fibronectin on cultured cells and structure and function studies of fibronectins in human and animal body fluids, tissues and cells. Affinity isolated antibody to human fibronectin can be used for immunofluorescent and immunoperoxidase staining of cultured cells, frozen sections and formalin fixed, paraffin-embedded tissues. Other fixatives, e.g. methacarn and ethanol, may also be used. Fibronectin also associates with collagen, actin and fibrins. In malignancies, fibronectin protein levels can be altered. In lung carninomas, expression is decreased. The FN-3 antibody recognizes a determinant on human cellular but not plasma fibronectin; this recognition is not lost upon trypsin treatment. Furthermore, FN-3 antibody has been shown to crossreact to bovine fibronectin. Applications Tested: This FN-3 antibody has been tested by immunohistochemistry on FFPE human placenta (with IHC Antigen Retrieval Solution -Low pH (cat. 00-4955)) and can be used at less than or equal to 10 μg/mL. Is is recommended that the antibody be carefully titrated for optimal performance in the assay of interest. Excitation: 488 nm; Emission: 519 nm; Laser: Blue Laser. Filtration: 0.2 μm post-manufacturing filtered.
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Wild animals
The study did not involve wild animals Field-collected samples The study did not involve field collected samples Ethics oversight All ethical approvals have been detailed in the manuscript. Surgery was performed at the Biomedical Services Unit at the University of Birmingham (UK) in accordance with the Home Office guidelines set out in the 1986 Animal Act (UK) and the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research.
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