C1R Mutations Trigger Constitutive Complement 1 Activation in Periodontal Ehlers-Danlos Syndrome

We report extensive functional studies of 16 C1R variants associated with pEDS by in-vitro overexpression studies in HEK293T cells followed by western blot, size exclusion chromatography and surface plasmon resonance analyses. Patient-derived skin fibroblasts were analyzed by western blot and Enzyme-linked Immunosorbent Assay (ELISA). Overexpression of C1R variants in HEK293T cells revealed that none of the pEDS variants was integrated into the C1 complex but cause extracellular presence of catalytic C1r/C1s activities. Variants showed domain-specific abnormalities of intracellular processing and secretion with preservation of serine protease function in the supernatant. In contrast to C1r wild type, and with the exception of a C1R missense variant disabling a C1q binding site, pEDS variants had different impact on the cell: retention of C1r fragments inside the cell, secretion of aggregates, or a new C1r cleavage site. Overexpression of C1R variants in HEK293T as well as western blot analyses of patient fibroblasts showed decreased levels of secreted C1r. Importantly, all available patient fibroblasts exhibited activated C1s and activation of externally added C4 in the supernatant while control cell lines secreted proenzyme C1s and showed no increase in C4 activation. The central elements in the pathogenesis of pEDS seem to be the intracellular activation of C1r and/or C1s, and extracellular presence of activated C1s that independently of microbial triggers can activate the ...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research

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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
We present the case of a 9-year-old boy with abdominal pain and retching. An abdominal computed tomography revealed free air under the diaphragm, and surgical exploration showed perforation of the sigmoid colon. Ultimately, he was diagnosed with vEDS. We review the literature and discuss the clinical presentation, diagnosis, and life-threatening crises associated with vEDS.
Source: Pediatric Emergency Care - Category: Emergency Medicine Tags: Illustrative Cases Source Type: research
This study refines the phenotype recently delineated in association with biallelic null alleles in TNXB, and adds three novel variants to its mutational repertoire. Unusual digital anomalies seem confirmed as possibly peculiar of TNXB-clEDS, while vascular fragility could be more than a chance association also in this Ehlers-Danlos syndrome type.
Source: Genes - Category: Genetics & Stem Cells Authors: Tags: Article Source Type: research
Conclusions There are only four reports of V-EDS causing splenic rupture in the literature to date. These patients were all adults and only one had not previously been diagnosed with V-EDS. All underwent splenectomy. While V-EDS presenting with abdominal visceral rupture in children has been reported, this is the first report of a child with V-EDS presenting with splenic rupture. It is the only case of splenic rupture secondary to V-EDS that has been managed minimally invasively by embolization. [...] Georg Thieme Verlag KG Stuttgart · New YorkArticle in Thieme eJournals: Table of contents  | &nb...
Source: European Journal of Pediatric Surgery Reports - Category: Surgery Authors: Tags: Review Article Source Type: research
AbstractA unique case of a patient with Ehlers ‐Danlos type IV syndrome was referred with aortic root aneurysm and previous cosmetic primary repair of pectus excavatum (PE) through a solid silicone onlay prosthesis. The patient underwent successful removal of the silicone prosthesis and one‐stage ascending aortic root replacement with concom itant Nuss procedure for repair of the PE.
Source: Journal of Cardiac Surgery - Category: Cardiovascular & Thoracic Surgery Authors: Tags: CASE REPORT Source Type: research
Responding to a paparazzi photo that captured her walking with her cane, Lena Dunham explained she has Ehlers-Danlos syndrome -- a group of disorders affecting the joints and skin.
Source: CNN.com - Health - Category: Consumer Health News Source Type: news
AbstractIn this paper, we describe the case of a 29-year-old Caucasian male who was reported dead in his home. In 2010, a diagnosis of acrogeria, Gottron type was obtained by genetic analysis of a COL3A1 gene mutation. External examination showed typical characteristics of acrogeria, Gottron type. Autopsy showed a full-thickness laceration in the inferior vena cava wall, which caused hemorrhage and death. Samples of inferior vena cava were processed by Masson trichrome staining, which revealed a reduction in vessel wall thickness and a decrease in the amount of elastic fibers. An antibody reaction with BCL-2 was intensely ...
Source: Forensic Science, Medicine, and Pathology - Category: Forensic Medicine Source Type: research
arina Colombi The Ehlers-Danlos syndromes (EDS) constitute a clinically and genetically heterogeneous group of connective tissue disorders. Tenascin X (TNX) deficiency is a rare type of EDS, defined as classical-like EDS (clEDS), since it phenotypically resembles the classical form of EDS, though lacking atrophic scarring. Although most patients display a well-defined phenotype, the diagnosis of TNX-deficiency is often delayed or overlooked. Here, we described an additional patient with clEDS due to a homozygous null-mutation in the TNXB gene. A review of the literature was performed, summarizing the most important and...
Source: Genes - Category: Genetics & Stem Cells Authors: Tags: Article Source Type: research
CONCLUSIONS: Osteogenesis imperfecta patients with haploinsufficient mutations had higher percentage of anisotropic collagen fibers alignment compared to other patient groups; all patients had a lower percentage of anisotropic samples compared to healthy controls. This correlated with higher average stiffness in the control group. Glycosaminoglycan content was lower in the control and haploinsufficient groups. In cells with PLOD1 mutations, there were no differences in PLOD2 expression. This proof of concept study was able to show differences in collagen fiber orientation between different patient groups which can potentia...
Source: Biochemical and Biophysical Research communications - Category: Biochemistry Authors: Tags: Biochem Biophys Res Commun Source Type: research
In this study we provide clinical and molecular presentation of two new patients with DSE related mcEDS. Analysing clinical exome data, a homozygous pathogenic DSE variant, c.1150_1157del p.(Pro384Trpfs*9), was identified in a 32 year old man with bilateral congenital talipes equinovarus, characteristic facial features, myopia, hyperextensible skin at the elbows, significant palmar wrinkling, bilateral inguinal hernias and chronic leg, back and joint pain. Electron microscopical examination of skin biopsy showed changes consistent with mild compensatory elastic fibre hypertrophy and mildly loose collagen bundles. The varia...
Source: European Journal of Medical Genetics - Category: Genetics & Stem Cells Authors: Tags: Eur J Med Genet Source Type: research
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