30 research outputs found
Osteopontin and Fibronectin Levels Are Decreased in Vitreous of Autoimmune Uveitis and Retinal Expression of Both Proteins Indicates ECM Re-Modeling
Autoimmune uveitis is an intraocular inflammation that arises through autoreactive T-cells attacking the inner eye, eventually leading to blindness. However, the contributing molecular pathomechanisms within the affected tissues remain as yet elusive. The extracellular matrix (ECM) is a highly dynamic structure that varies tremendously and influences the encompassing tissue. In order to assess ECM re-modeling in autoimmune uveitis, we investigated the expression of ECM molecules fibronectin and osteopontin in vitreous and retina samples. This was carried out in the only spontaneous animal model for human autoimmue uveitis, namely equine recurrent uveitis (ERU) that resembles the human disease in clinical as well as in immunopathological aspects. ERU is a naturally occurring autoimmune disease in horses that develops frequently and has already proved its value to study disease-related pathomechanisms. Western blot analysis of fibronectin and osteopontin in healthy and uveitic vitreous revealed significant reduction of both proteins in uveitis. Immunohistochemical expression of fibronectin in healthy retinas was restricted to the inner limiting membrane abutting vimentin positive Müller cell endfeet, while in uveitic sections, a disintegration of the ILM was observed changing the fibronectin expression to a dispersed pattern extending toward the vitreous. Retinal expression of osteopontin in control tissue was found in a characteristic Müller cell pattern illustrated by co-localization with vimentin. In uveitic retinas, the immunoreactivity of osteopontin in gliotic Müller cells was almost absent. The ability of Müller cells to express fibronectin and osteopontin was additionally shown by immunocytochemistry of primary cultured equine Müller cells and the equine Müller cell line eqMC-7. In conclusion, severe ECM re-modeling in autoimmune uveitis reported here, might affect the adhesive function of fibronectin and thus the anchoring of Müller cell endfeet to the ILM. Furthermore, the absence of osteopontin in gliotic Müller cells might represent reduced neuroprotection, an osteopontin attribute that is intensively discussed
Homeopathy for seasonal allergic rhinitis: rationale, design and methods of the three-armed randomized controlled HOMEOSAR trial
Background: Patients with seasonal allergic rhinitis (SAR) frequently use homeopathic therapy. Although there is some evidence that homeopathy may be effective in treating symptoms of SAR, there is a lack of high-quality clinical trials. Therefore, the aim of the homeopathy for SAR (HOMEOSAR) trial is to determine the efficacy of individualized or standardized homeopathic drug treatment compared to placebo regarding rhinitis-related quality of life in patients with SAR.
Methods: This randomized, placebo-controlled, double-blind, three-armed intervention study will be conducted at two university hospital outpatient clinics for complementary and integrative medicine in Berlin and in 12 office-based practices specializing in homeopathic treatment in Germany. A total of 270 patients with clinical symptoms of SAR and positive allergy test to birch and grass pollen will receive homeopathic anamnesis and subsequently be randomized into (a) standardized homeopathic drug treatment with Galphimia Glauca (potency D6), (b) individualized homeopathic drug treatment (D6), or (c) placebo. All three groups can receive on-demand rescue medication as needed. Treatment will consist of two consultations and daily intake of the study medication for 4 weeks during the pollen season. The primary outcome is the mean overall score of the Rhinitis Quality of Life Questionnaire (RQLQ) in weeks 3 and 4, analyzed using analysis of covariance (adjusted for baseline RQLQ overall score and study center). A closed testing procedure will be used to control the overall type I error comparing the 3 treatment groups. Secondary outcomes include the overall RQLQ and its seven domain scores, responder status (decrease in RQLQ overall score of at least 0.5 points compared to the baseline value), use of rescue medication, intensity of total and individual SAR symptoms based on visual analog scale, generic health-related quality of life, safety, utilization of health care resources and associated costs. In addition, a qualitative data analysis is planned.
Conclusion: The results of our study will contribute to clarifying the possible therapeutic effects of homeopathic drug treatment for patients with SAR
Profound Re-Organization of Cell Surface Proteome in Equine Retinal Pigment Epithelial Cells in Response to In Vitro Culturing
The purpose of this study was to characterize the cell surface proteome of native compared to cultured equine retinal pigment epithelium (RPE) cells. The RPE plays an essential role in visual function and represents the outer blood-retinal barrier. We are investigating immunopathomechanisms of equine recurrent uveitis, an autoimmune inflammatory disease in horses leading to breakdown of the outer blood-retinal barrier and influx of autoreactive T-cells into affected horses' vitrei. Cell surface proteins of native and cultured RPE cells from eye-healthy horses were captured by biotinylation, analyzed by high resolution mass spectrometry coupled to liquid chromatography (LC MS/MS), and the most interesting candidates were validated by PCR, immunoblotting and immunocytochemistry. A total of 112 proteins were identified, of which 84% were cell surface membrane proteins. Twenty-three of these proteins were concurrently expressed by both cell states, 28 proteins exclusively by native RPE cells. Among the latter were two RPE markers with highly specialized RPE functions: cellular retinaldehyde-binding protein (CRALBP) and retinal pigment epithelium-specific protein 65kDa (RPE65). Furthermore, 61 proteins were only expressed by cultured RPE cells and absent in native cells. As we believe that initiating events, leading to the breakdown of the outer blood-retinal barrier, take place at the cell surface of RPE cells as a particularly exposed barrier structure, this differential characterization of cell surface proteomes of native and cultured equine RPE cells is a prerequisite for future studies
Retinal glycoprotein enrichment by concanavalin a enabled identification of novel membrane autoantigen synaptotagmin-1 in equine recurrent uveitis.
Complete knowledge of autoantigen spectra is crucial for understanding pathomechanisms of autoimmune diseases like equine recurrent uveitis (ERU), a spontaneous model for human autoimmune uveitis. While several ERU autoantigens were identified previously, no membrane protein was found so far. As there is a great overlap between glycoproteins and membrane proteins, the aim of this study was to test whether pre-enrichment of retinal glycoproteins by ConA affinity is an effective tool to detect autoantigen candidates among membrane proteins. In 1D Western blots, the glycoprotein preparation allowed detection of IgG reactions to low abundant proteins in sera of ERU patients. Synaptotagmin-1, a Ca2+-sensing protein in synaptic vesicles, was identified as autoantigen candidate from the pre-enriched glycoprotein fraction by mass spectrometry and was validated as a highly prevalent autoantigen by enzyme-linked immunosorbent assay. Analysis of Syt1 expression in retinas of ERU cases showed a downregulation in the majority of ERU affected retinas to 24%. Results pointed to a dysregulation of retinal neurotransmitter release in ERU. Identification of synaptotagmin-1, the first cell membrane associated autoantigen in this spontaneous autoimmune disease, demonstrated that examination of tissue fractions can lead to the discovery of previously undetected novel autoantigens. Further experiments will address its role in ERU pathology
IL-33-induced metabolic reprogramming controls the differentiation of alternatively activated macrophages and the resolution of inflammation
Alternatively activated macrophages (AAMs) contribute to the resolution of inflammation and tissue repair. However, molecular pathways that govern their differentiation have remained incompletely understood. Here, we show that uncoupling protein-2-mediated mitochondrial reprogramming and the transcription factor GATA3 specifically controlled the differentiation of pro-resolving AAMs in response to the alarmin IL-33. In macrophages, IL-33 sequentially triggered early expression of pro-inflammatory genes and subsequent differentiation into AAMs. Global analysis of underlying signaling events revealed that IL-33 induced a rapid metabolic rewiring of macrophages that involved uncoupling of the respiratory chain and increased production of the metabolite itaconate, which subsequently triggered a GATA3-mediated AAM polarization. Conditional deletion of GATA3 in mononuclear phagocytes accordingly abrogated IL-33-induced differentiation of AAMs and tissue repair upon muscle injury. Our data thus identify an IL-4-independent and GATA3-dependent pathway in mononuclear phagocytes that results from mitochondrial rewiring and controls macrophage plasticity and the resolution of inflammation
Hebelomina (Agaricales) revisited and abandoned
Background and aims – The genus Hebelomina was established in 1935 by Maire to accommodate the new species Hebelomina domardiana, a white-spored mushroom resembling a pale Hebeloma in all aspects other than its spores. Since that time a further five species have been ascribed to the genus and one similar species within the genus Hebeloma. In total, we have studied seventeen collections that have been assigned to these seven species of Hebelomina. We provide a synopsis of the available knowledge on Hebelomina species and Hebelomina-like collections and their taxonomic placement.Methods – Hebelomina-like collections and type collections of Hebelomina species were examined morphologically and molecularly. Ribosomal RNA sequence data were used to clarify the taxonomic placement of species and collections.Key results – Hebelomina is shown to be polyphyletic and members belong to four different genera (Gymnopilus, Hebeloma, Tubaria and incertae sedis), all members of different families and clades. All but one of the species are pigment-deviant forms of normally brown-spored taxa. The type of the genus had been transferred to Hebeloma, and Vesterholt and co-workers proposed that Hebelomina be given status as a subsection of Hebeloma. In the meantime, Hebelomina-like Hebeloma, belonging to seven different species in three different sections, have been found. We conclude that Hebelomina should be abandoned as a supraspecific taxon
Hebelomina (Agaricales) revisited and abandoned
Background and aims – The genus Hebelomina was established in 1935 by Maire to accommodate the new species Hebelomina domardiana, a white-spored mushroom resembling a pale Hebeloma in all aspects other than its spores. Since that time a further five species have been ascribed to the genus and one similar species within the genus Hebeloma. In total, we have studied seventeen collections that have been assigned to these seven species of Hebelomina. We provide a synopsis of the available knowledge on Hebelomina species and Hebelomina-like collections and their taxonomic placement.Methods – Hebelomina-like collections and type collections of Hebelomina species were examined morphologically and molecularly. Ribosomal RNA sequence data were used to clarify the taxonomic placement of species and collections.Key results – Hebelomina is shown to be polyphyletic and members belong to four different genera (Gymnopilus, Hebeloma, Tubaria and incertae sedis), all members of different families and clades. All but one of the species are pigment-deviant forms of normally brown-spored taxa. The type of the genus had been transferred to Hebeloma, and Vesterholt and co-workers proposed that Hebelomina be given status as a subsection of Hebeloma. In the meantime, Hebelomina-like Hebeloma, belonging to seven different species in three different sections, have been found. We conclude that Hebelomina should be abandoned as a supraspecific taxon