ABSTRACT
An extracellular matrix protein plays an important role in skin wound healing. In the present study, we engineered a recombinant protein encompassing the 9th and 10th type III domains of fibronectin, and 4th FAS1 domain of beta ig-h3. This recombinant protein, in total, harbors four known-cell adhesion motifs for integrins: Pro-His-Ser-Arg-Asn (PHSRN) and Arg-Gly-Asp (RGD) in 9th and 10th type III domains of fibronectin, respectively, and Glu-Pro-Asp-Ile-Met (EPDIM) and Try-His (YH) in 4th FAS1 domain of big-h3, were designated to tetra-cell adhesion motifs (T-CAM). In vitro studies showed T-CAM supporting adhesion, migration and proliferation of different cell types including keratinocytes and fibroblasts. In an animal model of full-thickness skin wound, T-CAM exhibited excellent wound healing effects, superior to both 4th FAS1 domain of beta ig-h3 or 9th and 10th type III domains of fibronectin. Based on these results, T-CAM can be applied where enhancement of cell adhesion, migration and proliferation are desired, and it could be developed into novel wound healing drug.
Subject(s)
Animals , Humans , Mice , Rabbits , Amino Acid Motifs , Cell Adhesion/drug effects , Cell Line , Cell Movement/drug effects , Cell Proliferation/drug effects , Extracellular Matrix Proteins/chemistry , Fibroblasts/cytology , Fibronectins/chemistry , Keratinocytes/cytology , NIH 3T3 Cells , Recombinant Fusion Proteins/chemistry , Transforming Growth Factor beta/chemistry , Wound Healing/drug effectsABSTRACT
Fibronectin (FN), a large family of plasma and extracellular matrix (ECM) glycoproteins, plays an important role in leukocyte migration. In normal central nervous system (CNS), a fine and delicate mesh of FN is virtually restricted to the basal membrane of cerebral blood vessels and to the glial limitans externa. Experimental autoimmune encephalomyelitis (EAE), an inflammatory CNS demyelinating disease, was induced in Lewis rats with a spinal cord homogenate. During the preclinical phase and the onset of the disease, marked immunolabelling was observed on the endothelial luminal surface and basal lamina of spinal cord and brainstem microvasculature. In the paralytic phase, a discrete labelling was evident in blood vessels of spinal cord and brainstem associated or not with an inflammatory infiltrate. Conversely, intense immunolabelling was present in cerebral and cerebellar blood vessels, which were still free from inflammatory cuffs. Shortly after clinical recovery minimal labelling was observed in a few blood vessels. Brainstem and spinal cord returned to normal, but numerous inflammatory foci and demyelination were still evident near the ventricle walls, in the cerebral cortex and in the cerebellum. Intense expression of FN in brain vessels ascending from the spinal cord towards the encephalon preceded the appearance of inflammatory cells but faded away after the establishment of the inflammatory cuff. These results indicate an important role for FN in the pathogenesis of CNS inflammatory demyelinating events occurring during EAE
Subject(s)
Rats , Animals , Female , Central Nervous System , Encephalomyelitis, Autoimmune, Experimental/immunology , Fibronectins/immunology , Antibodies, Monoclonal , Central Nervous System/chemistry , Central Nervous System/ultrastructure , Encephalomyelitis, Autoimmune, Experimental/pathology , Encephalomyelitis/immunology , Encephalomyelitis/pathology , Fibronectins/chemistry , Immunohistochemistry , Rats, Inbred LewABSTRACT
Fibronectins are glycoproteins of the extracellular matrix composed of two 220-kDa polypeptide chains named A and B bound by two disulfide bridges. Both chains when digested with proteolytic enzymes give rise to six different domains named I to VI that are involved in the ligand properties of this molecule. Fibronectins bind fibrin, collagen, glycosaminoglycan residues and several integrins. In this study, using metabolic radiolabeling of alpha(5)beta(1) integrin with sodium sulfate, an immunoprecipitation reaction, inhibition of sulfate incorporation an a fibronectin-binding assay, we were able to detect this integrin as a sulfated molecule and this sulfation appears to regulate the integrin-fibronectin binding.
Subject(s)
Fibronectins/chemistry , Receptors, Fibronectin/chemistry , Binding Sites/physiology , Collagen/chemistry , Extracellular Matrix/chemistry , Fibrin/chemistry , Precipitin TestsABSTRACT
A novel arginine carboxypeptidase which is generated from plasma components during coagulation and possibly during some inflammatory reactions was recently reported to be decreased in rheumatoid arthritis. To further clarify this point, serum and plasma arginine carboxypeptidase together with plasma fibronectin and serum ceruloplasmin were determined in 37 patients with rheumatoid arthritis and 16 healthy controls. The study revealed significantly decreased serum enzyme activity levels as well as serum/plasma enzyme ratio compared with control, while both ceruloplasmin and fibronectin levels were increased significantly. Increased consumption of this enzyme for metabolism of inflammatory peptides such as C3a, C5a and bradykinin may be responsible. Significant negative correlation existed between serum enzyme activity as well as serum/plasma enzyme ratio and both fibronectin and ceruloplasmin. The negative correlation with fibronectin could be due to involvement of the enzyme in removal of this molecule, while negative correlation with ceruloplasmin could be due to the anti-inflammatory function of ceruloplasmin as a metal binding protein. No obvious correlation could be observed between indices of clinical severity, a finding suggesting that arginine carboxypeptidase deficiency could be partly due to inherited or acquired inability to generate this enzyme which results in an accelerated onset of the disease