Les connectivites: progrès thérapeutiques et place de la biothérapie [Connective tissue diseases: news in therapy, role of biologics agents].

Systemic lupus erythematosus and primary Sjögren's syndrom are the two major connective tissue diseases. A better knowledge of their physiopathology allows us today to propose an adapted therapy. Moreover progress concerns the oldest treatment, hydroxychloroquine, and biotherapy. Hydroxychloroquine is still an actual treatment for lupus, its positive effects are better understood today. Nevertheless it does not seem to be efficient to treat primitive Sjögren. Biotherapy targeting B lymphocytes seems efficient in these two connective tissue diseases. Anti TNF therapy is not recommended and seems to induce connective tissue diseases. The real news is the recent approval and reimbursement in Switzerland of the new drug belimumab (Benlysta) in case of moderate lupus.

Rôle du médecin interniste ou du généraliste dans le diagnostic et le suivi d'une collagénose [Family physician and connective tissue disorders].

The exact place of the family physician in the diagnosis and management of connective tissue disease is poorly studied moreover will essentially depend on the health system and the organization of medical network of each country. Connective tissue diseases are rare and complex diseases that require in all cases referral to specialists for their diagnosis as well as monitoring. All patients must still keep a family doctor whose importance increases more and more as our specialized treatments prolong survival of patients who become chronically ill with multi-organic sequelae. A closely interaction between the various specialists and family physicians is necessary to ensure a good long-term follow-up.

Les biothérapies dans le lupus érythémateux disséminé et tes connectivites: nouvelles thérapeutiques [Treatment of connective tissue diseases with biological agents]

As B-cells are crucial for the production of antibodies and also in antigen presentation, they can play an important role in autoimmune connective tissue disease. B-cell surface antigens and receptors which are capable of activating B-cell function have been proposed as targets for therapy in these diseases. Anti-B cell treatments have been used recently in SLE and primary Sjogren's syndrome in a number of open studies, notably anti-CD20 (rituximab), with encouraging results. An anti-BAFF antibody (belimumab) has been tested in patients with SLE and also showed positive results in patients with increased levels of autoantibodies. In contrast, anti-TNF therapy in connective tissue disease and in RA can increase the levels of autoantibodies. Further studies are needed to define the place of these novel treatments in the management of autoimmune connective tissue diseases.

The zinc transporter SLC39A13/ZIP13 is required for connective tissue development; its involvement in BMP/TGF-beta signaling pathways.

BACKGROUND: Zinc (Zn) is an essential trace element and it is abundant in connective tissues, however biological roles of Zn and its transporters in those tissues and cells remain unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that mice deficient in Zn transporter Slc39a13/Zip13 show changes in bone, teeth and connective tissue reminiscent of the clinical spectrum of human Ehlers-Danlos syndrome (EDS). The Slc39a13 knockout (Slc39a13-KO) mice show defects in the maturation of osteoblasts, chondrocytes, odontoblasts, and fibroblasts. In the corresponding tissues and cells, impairment in bone morphogenic protein (BMP) and TGF-beta signaling were observed. Homozygosity for a SLC39A13 loss of function mutation was detected in sibs affected by a unique variant of EDS that recapitulates the phenotype observed in Slc39a13-KO mice. CONCLUSIONS/SIGNIFICANCE: Hence, our results reveal a crucial role of SLC39A13/ZIP13 in connective tissue development at least in part due to its involvement in the BMP/TGF-beta signaling pathways. The Slc39a13-KO mouse represents a novel animal model linking zinc metabolism, BMP/TGF-beta signaling and connective tissue dysfunction.

Mutations in B3GALT6, which encodes a glycosaminoglycan linker region enzyme, cause a spectrum of skeletal and connective tissue disorders.

Proteoglycans (PGs) are a major component of the extracellular matrix in many tissues and function as structural and regulatory molecules. PGs are composed of core proteins and glycosaminoglycan (GAG) side chains. The biosynthesis of GAGs starts with the linker region that consists of four sugar residues and is followed by repeating disaccharide units. By exome sequencing, we found that B3GALT6 encoding an enzyme involved in the biosynthesis of the GAG linker region is responsible for a severe skeletal dysplasia, spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMD-JL1). B3GALT6 loss-of-function mutations were found in individuals with SEMD-JL1 from seven families. In a subsequent candidate gene study based on the phenotypic similarity, we found that B3GALT6 is also responsible for a connective tissue disease, Ehlers-Danlos syndrome (progeroid form). Recessive loss-of-function mutations in B3GALT6 result in a spectrum of disorders affecting a broad range of skeletal and connective tissues characterized by lax skin, muscle hypotonia, joint dislocation, and spinal deformity. The pleiotropic phenotypes of the disorders indicate that B3GALT6 plays a critical role in a wide range of biological processes in various tissues, including skin, bone, cartilage, tendon, and ligament.

NBAS mutations cause a multisystem disorder involving bone, connective tissue, liver, immune system, and retina.

We report two unrelated patients with a multisystem disease involving liver, eye, immune system, connective tissue, and bone, caused by biallelic mutations in the neuroblastoma amplified sequence (NBAS) gene. Both presented as infants with recurrent episodes triggered by fever with vomiting, dehydration, and elevated transaminases. They had frequent infections, hypogammaglobulinemia, reduced natural killer cells, and the Pelger-Huët anomaly of their granulocytes. Their facial features were similar with a pointed chin and proptosis; loose skin and reduced subcutaneous fat gave them a progeroid appearance. Skeletal features included short stature, slender bones, epiphyseal dysplasia with multiple phalangeal pseudo-epiphyses, and small C1-C2 vertebrae causing cervical instability and myelopathy. Retinal dystrophy and optic atrophy were present in one patient. NBAS is a component of the synthaxin-18 complex and is involved in nonsense-mediated mRNA decay control. Putative loss-of-function mutations in NBAS are already known to cause disease in humans. A specific founder mutation has been associated with short stature, optic nerve atrophy and Pelger-Huët anomaly of granulocytes (SOPH) in the Siberian Yakut population. A more recent report associates NBAS mutations with recurrent acute liver failure in infancy in a group of patients of European descent. Our observations indicate that the phenotypic spectrum of NBAS deficiency is wider than previously known and includes skeletal, hepatic, metabolic, and immunologic aspects. Early recognition of the skeletal phenotype is important for preventive management of cervical instability. © 2015 Wiley Periodicals, Inc.

Female pelvic floor disorders – outcome after mesh-augmented procedures and studies on vaginal connective tissue

Pelvic floor disorders, such as urinary incontinence (UI) and pelvic organ prolapse (POP), are common disorders in women. Because of the prolonged life expectancy the prevalence of UI and POP and the probability of ending up in surgery are increasing. However, the pathophysiology behind these disorders is still unsolved. The aim of this thesis is to study possible alterations in the connective tissue in the vaginal wall in patients with and without POP. The long-term outcome and complications of mid-urethral slings (MUS) and mesh-augmented POP surgery were studied in heterogenic patient populations. More elastin and a slight increase in immunostaining of type III and V collagens in tissue samples were obtained from patients with POP compared to controls in whom type I collagen was more prominent. The studies assessing the mesh-augmented procedures revealed good efficacy and high patient satisfaction after a long-term follow-up. Patients operated on because of mixed incontinence and with BMI >30 kg/m² reported significantly more urinary symptoms and a lower quality of life than the patients operated on because of stress urinary incontinence and the ones with BMI ≤30 kg/m². The objective outcome was equal between the groups. Mesh exposure through vaginal mucosa occurred in 23 % of the patients after POP surgery, most of these being asymptomatic. There are alterations in connective tissues in patients with POP. Mid-urethral sling procedures produced good long-term cure rates and patient satisfaction. As to the prolapse surgery, in spite of relatively high exposure rate, mesh-augmented procedure proved to be safe and effective method for the correction of POP.

Hepatitis C virus seroprevalence and genotypes in patients with diffuse connective tissue diseases and spondyloarthropathies

Many extrahepatic manifestations, including rheumatic diseases, have been reported to be associated with hepatitis C virus (HCV) infection. In order to investigate the prevalence of HCV infection among patients with rheumatic diseases, in the present study we interviewed 367 patients and tested their blood samples for HCV antibodies (anti-HCV) by an enzyme-linked immunosorbent assay. Anti-HCV-reactive samples were retested for confirmation by a line immunoassay and also for HCV RNA detection by the polymerase chain reaction. HCV RNA-positive samples were genotyped by INNO-LIPA. An overall HCV infection prevalence of 1.9% (7/367) was found. Of the 7 HCV-infected patients, 4 had systemic lupus erythematosus and 3 rheumatoid arthritis, resulting in positivity rates of 2.3 and 3.4%, respectively. HCV RNA genotyping revealed the presence of subtypes 1a (57.1%), 1b (28.6%) and 3a (14.3%). The clinical course was favorable for all HCV-infected patients, except one, who died due to renal insufficiency related to lupus nephritis. These results demonstrate a low HCV infection prevalence among the population studied. In the few positive cases, we observed no adverse influence of this infection on the clinical evolution of the rheumatic disease.

Study of chemical properties and evaluation of collagen in mantle, epidermal connective tissue and tentacle of Indian Squid, Loligo duvauceli Orbigny

The chemical composition and evaluation of Indian squid (Loligo duvauceli) mantle, epidermal connective tissue and tentacle is investigated in this current study. It is observed that squid mantle contains 22.2% total protein; 63.5% of the total protein is myofibrillar protein. The unique property of squid myofibrillar protein is its water solubility. Squid mantle contains 12.0% total collagen. Epidermal connective tissue has highest amounts of total collagen (17.8%). SDS-PAGE of total collagen identified high molecular weight α-, β- and γ- sub-chains. Amino acid profile analysis indicates that mantle and tentacle contain essential amino acids. Arginine forms a major portion of mantle collagen (272.5 g/100 g N). Isoleucine, glutamic acid and lysine are other amino acids that are found in significantly high amounts in the mantle. Sulphur containing cystine is deficit in mantle collagen. Papain digest of mantle and epidermal connective tissue is rich in uronic acid, while papain digest, collagenase digest and urea digest of epidermal connective tissue has significant amounts of sialic acid (25.2, 33.2 and 99.8 μmol /100 g, respectively). PAS staining of papain digest, collagenase digest and urea digest also identify the association of hexoses with low molecular weight collagen fragments. Histochemical sectioning also emphasized the localized distribution of collagen in epidermal and dermal region and very sparse fibres traverse the myotome bundles

Characterisation of connective tissue from the hypertrophic skeletal muscle of myostatin null mice

Myostatin is a potent inhibitor of muscle development. Genetic deletion of myostatin in mice results in muscle mass increase, with muscles often weighing three times their normal values. Contracting muscle transfers tension to skeletal elements through an elaborate connective tissue network. Therefore, the connective tissue of skeletal muscle is an integral component of the contractile apparatus. Here we examine the connective tissue architecture in myostatin null muscle. We show that the hypertrophic muscle has decreased connective tissue content compared with wild-type muscle. Secondly, we show that the hypertrophic muscle fails to show the normal increase in muscle connective tissue content during ageing. Therefore, genetic deletion of myostatin results in an increase in contractile elements but a decrease in connective tissue content. We propose a model based on the contractile profile of muscle fibres that reconciles this apparent incompatible tissue composition phenotype.

Phenylephrine and endothelin-1 upregulate connective tissue growth factor in neonatal rat cardiac myocytes.

Cardiac hypertrophy is associated with hypertrophic growth of cardiac myocytes and increased fibrosis. Much is known of the stimuli which promote myocyte hypertrophy and the changes associated with the response, but the links between the two are largely unknown. Using subtractive hybridization, we identified three genes which are acutely (<1 h) upregulated in neonatal rat ventricular myocytes exposed to the alpha-adrenergic agonist, phenylephrine. One represented connective tissue growth factor (CTGF) which is implicated in fibrosis and promotes hypertrophy in other cells. We further examined the expression of CTGF mRNA and protein in cardiac myocytes using quantitative PCR and immunoblotting, confirming that phenylephrine increased CTGF mRNA (maximal within 1 h) and protein (increased over 4 - 24 h). Endothelin-1 promoted a greater, though transient, increase in CTGF mRNA, but the increase in CTGF protein was sustained over 8 h. Neither agonist increased CTGF mRNA in cardiac non-myocytes. By increasing the expression of CTGF in cardiac myocytes, hypertrophic agonists such as phenylephrine and endothelin-1 may promote fibrosis. CTGF may also propagate the hypertrophic response initiated by these agonists.

Subepithelial connective tissue graft for root coverage in smokers and non-smokers: A clinical and histologic controlled study in humans

Background: The aim of this study was to evaluate root coverage of gingival recessions and to compare graft vascularization in smokers and non-smokers. Methods: Thirty subjects, 15 smokers and 15 non-smokers, were selected. Each subject had one Miller Class I or II recession in a non-molar tooth. Clinical measurements of probing depth (PD), relative clinical attachment level (CAL), gingival recession (GR), and width of keratinized tissue (KT) were determined at baseline and 3 and 6 months after surgery. The recessions were treated surgically with a coronally positioned flap associated with a subepithelial connective tissue graft. A small portion of this graft was prepared for immunohistochemistry. Blood vessels were identified and counted by expression of factor VIII-related antigen-stained endothelial cells. Results: Intragroup analysis showed that after 6 months there a was gain in CAL, a decrease in GR, and an increase in KT for both groups (P<0.05), whereas changes in PD were not statistically significant. Smokers had less root coverage than non-smokers (58.02% +/- 19.75% versus 83.35% +/- 18.53%; P<0.05). Furthermore, the smokers had more GR (1.48 +/- 0.79 mm versus 0.52 +/- 0.60 mm) than the nonsmokers (P<0.05). Histomorphometry of the donor tissue revealed a blood vessel density of 49.01 +/- 11.91 vessels/200x field for non-smokers and 36.53 +/- 10.23 vessels/200x field for smokers (P<0.05). Conclusion: Root coverage with subepithelial connective tissue graft was negatively affected by smoking, which limited and jeopardized treatment results.

The connective tissue of the adductor canal - a morphological study in fetal and adult specimens

The adductor canal is a conical or pyramid-shaped pathway that contains the femoral vessels, saphenous nerve and a varying amount of fibrous tissue. It is involved in adductor canal syndrome, a claudication syndrome involving young individuals. Our objective was to study modifications induced by aging on the connective tissue and to correlate them to the proposed pathophysiological mechanism. The bilateral adductor canals and femoral vessels of four adult and five fetal specimens were removed en bloc and analyzed. Sections 12 mu m thick were obtained and the connective tissue studied with Sirius Red, Verhoeff, Weigert and Azo stains. Scanning electron microscopy (SEM) photomicrographs of the surfaces of each adductor canal were also analyzed. Findings were homogeneous inside each group. The connective tissue of the canal was continuous with the outer layer of the vessels in both groups. The pattern of concentric, thick collagen type I bundles in fetal specimens was replaced by a diffuse network of compact collagen bundles with several transversal fibers and an impressive content of collagen III fibers. Elastic fibers in adults were not concentrated in the thick bundles but dispersed in line with the transversal fiber system. A dynamic compression mechanism with or without an evident constricting fibrous band has been proposed previously for adductor canal syndrome, possibly involving the connective tissue inside the canal. The vessels may not slide freely during movement. These age-related modifications in normal individuals may represent necessary conditions for this syndrome to develop.

Connective tissue mast cells are the target of formaldehyde to induce tracheal hyperresponsiveness in rats: Putative role of leukotriene B(4) and nitric oxide

Formaldehyde (FA) exposure induces upper airways irritation and respiratory abnormalities, but its mechanisms are not understood. Since mast cells are widely distributed in the airways, we hypothesized that FA might modify the airways reactivity by mechanism involving their activation. Tracheal rings of rats were incubated with Dulbecco`s modified medium culture containing FA (0.1 ppm) in 96-well plastic microplates in a humid atmosphere. After 30 min, 6 h, and 24-72 h, the rings were suspended in an organ bath and dose-response curve to methacholine (MCh) were determined. incubation with FA caused a transient tracheal hyperresponsiveness to MCh that was independent from tracheal epithelium integrity. Connective tissue mast cell depletion caused by compound 48/80 or mast cell activation by the allergic reaction, before exposure of tracheal rings to FA prevented the increased responsiveness to MCh. LTB(4) concentrations were increased in the culture medium of tracheas incubated with FA for 48 h, whereas the LTB(4)-receptor antagonist MK886 (1 mu M) added before FA exposure rendered the tracheal rings normoreactive to MCh. In addition, FA exposure did not cause hyperresponsiveness in tracheal segments incubated with L-arginine (1 mu M). We suggest that airway connective tissue mast cells constitute the target and may provide the increased LTB(4) generation as well as an elevated consumption of NO leading to tracheal hyperresponsiveness to MCh. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

An alternative technique to the harvesting of a connective tissue graft from a thin palate: Enhanced wound healing

This article describes an alternative surgical approach to the harvesting of subepithelial connective tissue grafts from thin palates. A partial-thickness flap is raised, and a graft composed of epithelium and connective tissue is removed from the palate. The superficial layer ( epithelium and a thin zone of connective tissue) is then dissected from the graft and replaced at the donor site to facilitate faster healing. The subjacent layer of connective tissue is placed as needed to obtain root coverage. The clinical application of this technique is described in two patients with multiple gingival recessions.