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ID PMID Title PublicationDate abstract
24843873 Intramolecular polyspecificity in CD4 T-cell recognition of Ad-restricted epitopes of prot 2014 May T-cell recognition of MHC–peptide complexes shows a high degree of polyspecificity extending to recognition of a large number of structurally unrelated peptides. Examples of polyspecificity reported to date are confined to recognition of epitopes from distinct proteins or synthetic peptide libraries. Here we describe intramolecular polyspecificity of CD4 T cells specific for several epitopes within proteoglycan aggrecan, a structural glycoprotein of cartilage and candidate autoantigen in rheumatoid arthritis. T-cell hybridomas from aggrecan-immunized mice recognized four structurally unrelated epitopes from the G1 domain of aggrecan, but not other aggrecan epitopes or a variety of other peptide epitopes restricted by the same MHC class II allele. We also showed that the hierarchy of cross-reactivity broadly correlated with the strength of peptide binding to MHC class II. Similar polyspecificity was observed in responses of lymph node cells from peptide-immunized mice, suggesting polyspecificity of a significant proportion of the in vivo aggrecan specific T-cell repertoire. Polyspecific recognition of several epitopes within the same autoantigen may provide a novel mechanism to reach the activation threshold of low-affinity autoreactive T cells in the initiation of autoimmune diseases.
25461470 Autoimmune thyroid disorders. 2015 Feb Autoimmune thyroid diseases (AITD) result from a dysregulation of the immune system leading to an immune attack on the thyroid. AITD are T cell-mediated organ-specific autoimmune disorders. The prevalence of AITD is estimated to be 5%; however, the prevalence of antithyroid antibodies may be even higher. The AITD comprise two main clinical presentations: Graves' disease (GD) and Hashimoto's thyroiditis (HT), both characterized by lymphocytic infiltration of the thyroid parenchyma. The clinical hallmarks of GD and HT are thyrotoxicosis and hypothyroidism, respectively. The mechanisms that trigger the autoimmune attack to the thyroid are still under investigation. Epidemiological data suggest an interaction among genetic susceptibility and environmental triggers as the key factor leading to the breakdown of tolerance and the development of disease. Recent studies have shown the importance of cytokines and chemokines in the pathogenesis of AT and GD. In thyroid tissue, recruited T helper 1 (Th1) lymphocytes may be responsible for enhanced IFN-γ and TNF-α production, which in turn stimulates CXCL10 (the prototype of the IFN-γ-inducible Th1 chemokines) secretion from the thyroid cells, therefore creating an amplification feedback loop, initiating and perpetuating the autoimmune process. Associations exist between AITD and other organ specific (polyglandular autoimmune syndromes), or systemic autoimmune disorders (Sjögren's syndrome, rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, cryoglobulinemia, sarcoidosis, psoriatic arthritis). Moreover, several studies have shown an association of AITD and papillary thyroid cancer. These data suggest that AITD patients should be accurately monitored for thyroid dysfunctions, the appearance of thyroid nodules, and other autoimmune disorders.
23559388 Adalimumab-associated antiphospholipid syndrome: a case report and review of the literatur 2013 Jul This study aims for the presentation of the first reported case of adalimumab-associated antiphospholipid syndrome (APS) and review of the literature on adalimumab-induced vasculitis and APS. A case of APS associated with adalimumab use in a 67-year-old woman is reported. The English medical literature was reviewed for antitumor necrosis factor (TNF) agents and their association with APS and vasculitis. Adalimumab is a fully humanized monoclonal antibody targeted against TNF alpha that is widely used in the treatment of rheumatoid arthritis, juvenile idiopathic arthritis, ankylosing spondylitis, psoriatic arthritis, psoriasis, and Crohn's disease. Literature review reveals several cases of anti-TNF-induced vasculitis including cases associated with adalimumab. We report the first case of adalimumab-induced APS in a 67-year-old woman who developed APS and vasculitis associated with de novo positive anti-cardiolipin (aCL) antibody following the third dose of adalimumab therapy for the treatment of spondyloarthropathy. This is the first case demonstrating that a short course of adalimumab therapy may induce immunoglobulin M aCL autoantibodies leading to APS. With the growing use of anti-TNF medications in immune-mediated and inflammatory diseases, adalimumab and other anti-TNF medications should be considered as a possible explanation for APS.
25368531 Polyarticular juvenile idiopathic arthritis - epidemiology and management approaches. 2014 Juvenile idiopathic arthritis (JIA) is a group of disorders characterized by arthritis persisting for at least 6 weeks with onset before the age of 16 years. Within this cluster of conditions, the polyarticular form (involving more than four joints within the first 6 months) is further divided based on the presence of rheumatoid factor. Children with polyarticular JIA pose unique diagnostic and therapeutic challenges compared to children with involvement of fewer joints. Polyarticular JIA patients tend to have a more refractory course and therefore are at increased risk for joint damage, resulting in poorer functional outcomes and decreased quality of life. Although the ability to treat this disorder continues to improve, especially with the advent of biologic agents, there is still much about the epidemiology and pathogenesis of polyarticular JIA that is unknown. The epidemiology of polyarticular JIA varies worldwide with a vast difference in reported cases between different global regions as well as within individual countries. Several genetic risk loci have been identified conferring increased susceptibility to JIA, many within the human leukocyte antigen region. Beyond the genome, environmental factors also seem to contribute to the etiology of polyarticular JIA. This review article will focus on the epidemiology and current treatments of polyarticular JIA and briefly discuss genetic and environmental influences on the pathogenesis of JIA as well as new and emerging therapies.
24845796 Poly(ADP-ribose) polymerase-1 inhibitor modulates T regulatory and IL-17 cells in the prev 2014 Aug Rheumatoid arthritis (RA) is one of the major autoimmune diseases of global prevalence. Irrespective of much research in RA disease, no drugs with capable safety profiles are yet available. Poly(ADP-ribose) polymerase-1 (PARP-1) synthesizes and transfers ADP ribose polymers to target proteins, and regulates DNA repair and genomic integrity maintenance. PARP-1 also plays a crucial role in the progression of the inflammatory response, and its inhibition confers protection in several models of inflammatory disorders. We investigated the possible anti-arthritic effects of the PARP-1 inhibitor 5-aminoisoquinolinone (5-AIQ) in a mouse model of adjuvant induced arthritis (AIA). In this study, we examined the effects of 5-AIQ on the key mediators of arthritic inflammation, namely, edema and arthritic score, T cell subsets, regulatory T (Treg) cells, IL-17A, GITR expressing cells, NF-kB p65, IkB-α and pro and anti-inflammatory mediators mRNA expression levels. PARP-1 inhibition 5-AIQ treatment significantly attenuated the severity of AIA, reduced the arthritis scores, a substantial reduction in the levels of T cell subsets, IL-17A, NF-kB p65, GITR expressing cells, and as well as the pro-inflammatory mediators. However, 5-AIQ significantly up-regulated the number of Tregs cells, IkB-α levels and mRNA expression of anti-inflammatory mediators. Our results suggest that treatment with 5-AIQ attenuated AIA in mice might offer a promising alternative/adjunct treatment for RA.
25439190 Parthenolide inhibits pro-inflammatory cytokine production and exhibits protective effects 2015 May OBJECTIVES: Progressive destruction of synovial joint cartilage and bone occurs in pathological conditions such as rheumatoid arthritis (RA) because of the overproduction of pro-inflammatory cytokines and activation of nuclear factor kappa B (NF-κB). Through the screening of NF-κB inhibitors by a luciferase reporter gene assay, we identified parthenolide (PAR) as the most potent NF-κB inhibitor, among several PAR analogue compounds. This study was undertaken to determine whether PAR inhibits pro-inflammatory cytokine production, cartilage degradation, and inflammatory arthritis. METHOD: The mRNA levels of pro-inflammatory cytokines were examined by real-time polymerase chain reaction (PCR). Proteoglycan content and release were determined by measuring glycosaminoglycan (GAG) levels using the dimethylmethylene blue (DMMB) dye-binding assay. The potential role of PAR in treatment of arthritis was studied using a collagen-induced arthritis (CIA) model. RESULTS: We established that PAR, as a prototype compound, suppressed lipopolysaccharide (LPS)- and tumour necrosis factor (TNF)-α-induced increases in matrix metalloproteinase (MMP)-1, MMP-3, inducible nitric oxide synthase (iNOS), and interleukin (IL)-1β mRNA in chondrocytes. In addition, PAR prevented proteoglycan degradation triggered by pro-inflammatory cytokines. PAR treatment at the onset of CIA symptoms significantly reduced synovitis, inflammation, and pannus formation scores. Reduced synovial inflammation after PAR treatment was also reflected in significantly less bone erosion and cartilage damage. CONCLUSIONS: These data indicate a protective effect of PAR on the catabolic insults of pro-inflammatory cytokines on chondrocyte metabolism and GAG release in vitro and in CIA. PAR had anti-inflammatory and structure-modifying effects on experimental arthritis, suggesting that PAR may be useful as a potential alternative or adjunct therapy for inflammatory arthritis.
24520814 Anti-arthritis effects of (E)-2,4-bis(p-hydroxyphenyl)-2-butenal are mediated by inhibitio 2014 Jun BACKGROUND AND PURPOSE: Products of Maillard reactions between aminoacids and reducing sugars are known to have anti-inflammatory properties. Here we have assessed the anti-arthritis effects of (E)-2,4-bis(p-hydroxyphenyl)-2-butenal and its possible mechanisms of action. EXPERIMENTAL APPROACH: We used cultures of LPS-activated macrophages (RAW264.7 cells) and human synoviocytes from patients with rheumatoid arthritis for in vitro assays and the collagen-induced arthritis model in mice. NO generation, iNOS and COX2 expression, and NF-κB/IKK and STAT3 activities were measured in vitro and in joint tissues of arthritic mice, along with clinical scores and histopathological assessments. Binding of (E)-2,4-bis(p-hydroxyphenyl)-2-butenal to STAT3 was evaluated by a pull-down assay and its binding site was predicted using molecular docking studies with Autodock VINA. KEY RESULTS: (E)-2,4-bis(p-hydroxyphenyl)-2-butenal (2.5-10 μg·mL(-1) ) inhibited LPS-inducedNO generation, iNOS and COX2 expression, and NF-κB/IKK and STAT3 activities in macrophage and human synoviocytes. This compound also suppressedcollagen-induced arthritic responses in mice by inhibiting expression of iNOS and COX2, and NF-κB/IKK and STAT3 activities; it also reduced bone destruction and fibrosis in joint tissues. A pull-down assay showed that (E)-2,4-bis(p-hydroxyphenyl)-2-butenal interfered with binding of ATP to STAT3. Docking studies suggested that (E)-2,4-bis(p-hydroxyphenyl)-2-butenal bound to the DNA-binding interface of STAT3 possibly inhibiting ATP binding to STAT3 in an allosteric manner. CONCLUSIONS AND IMPLICATIONS: (E)-2,4-bis(p-hydroxyphenyl)-2-butenal exerted anti-inflammatory and anti-arthritic effects through inhibition of the NF-κB/STAT3 pathway by direct binding to STAT3. This compound could be a useful agent for the treatment of arthritic disease.
25065774 Comparison of the discontinuation rates and side-effect profiles of pilocarpine and cevime 2014 Jul OBJECTIVES: There are currently no head-to-head comparisons of sialagogues for Primary Sjögren's syndrome (pSS). We compared the tolerability and side effect profile of pilocarpine and cevimeline in patients with pSS and determined clinical, laboratory and pathological variables associated with therapeutic failure. METHODS: We retrospectively reviewed the use of pilocarpine and cevimeline in 118 patients with pSS who fulfilled the 2002 American European Consensus Group criteria in a University-based setting. Clinical, laboratory and pathological baseline variables were collected. Failure of therapy was defined as the clinician or patient's decision to stop treatment either due to lack of efficacy or side effects. RESULTS: Cevimeline was associated with lower failure rates compared to pilocarpine among first-time users: 27% vs. 47% (p=0.02), and all users: 32% vs. 61% (p<0.001). Severe sweating was the most frequent side effect leading to cessation of therapy and occurred more frequently in pilocarpine (25%) than cevimeline (11%) users (p=0.02). Patients who previously failed one secretagogue were less likely to discontinue treatment with the other agent, 52% of first-time users vs. 27% of second-time users (p=0.004). Only ANA positivity was associated with failure: [59% vs. 38%] (p=0.03). CONCLUSIONS: pSS patients were more likely to continue cevimeline than pilocarpine long-term due to fewer reported side effects with cevimeline. Therapeutic failure of one secretagogue did not predict similar results with the other since second time users were more likely to continue long-term treatment.
24931100 miR-146a and miR-155 expression in PBMCs from patients with Sjögren's syndrome. 2014 Nov BACKGROUND: An increasing number of studies have revealed that microRNA (miRNA) contributes to the pathogenesis of autoimmune diseases. The objective of this study is to investigate the miR-146a and miR-155 levels in peripheral mononuclear blood cells from patients with primary Sjögren's syndrome (pSS) who were not receiving medications and to examine the correlations between these miRNA levels and the clinical features of the disease. METHOD: Using real-time polymerase chain reaction analysis of miRNAs, the miR-146a and miR-155 expression levels were assessed in peripheral mononuclear blood cells from 27 patients with pSS and 22 healthy controls, and the relationships between these miRNA levels and the visual analog scale (VAS) scores for dry mouth, dry eyes, and parotid gland swelling were investigated. RESULTS: Compared with the healthy controls, the miR-146a expression level was significantly increased in the patients with pSS (P = 0.0182) and was positively correlated with the VAS scores for parotid swelling (r = 0.4475, P = 0.0192) and dry eyes (r = 0.4051, P = 0.0361). Although the miR-155 expression level was significantly decreased in the patients with pSS (P = 0.0131), the miR-155 expression positively correlated with the VAS score for dry eyes (r = 0.4894, P = 0.0096). CONCLUSION: Our results demonstrated miR-146a overexpression and miR-155 underexpression in the peripheral mononuclear blood cells of the patients with pSS. Furthermore, the expression levels of these miRNAs correlated with the patients' clinical features. Our data suggest that miR-146a and miR-155 might play important roles in the pathogenesis of pSS and that their expression levels may be useful for diagnosing pSS and for predicting disease activity and therapeutic responses.
24637076 Infection and autoimmunity in Sjogren's syndrome: a clinical study and comprehensive revie 2014 Jun Sjögren's syndrome (SS) is an autoimmune disease characterized primarily by lymphocytic infiltration of the exocrine glands, and autoantibody production. Multiple environmental factors affecting an individual with a genetic susceptibility may trigger the development of SS. Herein, we aimed to evaluate links between the different pebbles in the mosaic of SS. Demographic, clinical data and blood samples were gathered from 82 consecutive patients with SS, and 139 healthy controls. Samples were analyzed for infectious serology and auto-antibodies as well as for relevant genetic mutations (TAP genes) and cytokines levels. An immune response (IgG) against Epstein-Barr virus (EBV) early antigen (EA) was positively associated with SS (OR 4; 95% CI: 1.82-8.83, p = 0.001) while a protective effect of IgG anti-cytomegalovirus (CMV) was observed (OR 0.3; 95%CI: 0.16-0.74, p = 0.009). Anti-Ro/SSA, anti-LA/SSB, anti-nuclear, anti-gliadin, anti-TTG-IgG and anti-RNP antibodies were statistically more prevalent among SS patients than controls. Notably, the presence of anti-Ro/SSA and anti La/SSB correlated with anti-EBVEA IgG (OR 3.1; 95%CI: 1.08-8.74) and (OR 3.9; 95%CI: 1.37-10.96) respectively. Autoantibodies, cytokines and several genetic markers correlated with clinical manifestation of SS. Our data suggest that infectious agents may play both a causative and protective role in the pathogenesis of SS. Moreover certain autoantibodies, cytokines and specific TAP alleles correlate with clinical manifestations of SS, and may enable better prediction and/or directed therapy once confirmed in future studies.
23890196 Autologous serum eye drops diluted with sodium hyaluronate: clinical and experimental comp 2014 Feb PURPOSE: To assess the efficacy of sodium hyaluronate as vehicle for diluting autologous serum. METHODS: The concentration and temporal stability of EGF, TGF-β, PDGF-AB and albumin in fresh and frozen samples of autologous serum diluted with sodium hyaluronate and saline solution, as well as the pH, osmolarity and density was studied. In parallel, the clinic effects of autologous serum diluted to 20% with sodium hyaluronate were compared with another solution of autologous serum diluted to 20% with saline in a prospective, comparative, randomized and double-blind study in 26 patients (52 eyes) with Sjögren syndrome. Patients underwent a complete ophthalmic assessment including tear film evaluation and corneal and conjunctival impression cytology at the beginning of the study and 2 months later. RESULTS: The growth factor (GF) concentration remained stable during 1 month at 4°C both in fresh and defrosted samples without any differences being found between both preparations. No differences were found related to osmolarity, pH and density between these preparations before and after frosting. Autologous serum diluted with sodium hyaluronate caused a significant improvement of the tear film stability, fluorescein and rose Bengal stain, break-up time, corneal and conjunctival squamous metaplasia as well as in the patient subjective perception. CONCLUSIONS: Sodium hyaluronate is an excellent vehicle for diluting autologous serum due to the gradual release of GF and increasing their duration and effect on the ocular surface. Preparations diluted with sodium hyaluronate are better tolerated by patients and require a lower number of drops administrations.
25088171 Efficacy of extracranial-intracranial bypass for progressive middle cerebral artery occlus 2014 Sep Sjögren syndrome affecting the major cerebral arteries is rare, and an optimal therapeutic strategy to counteract such a lesion has not yet been established. We herein report a case of a 39-year-old woman with a history of primary Sjögren syndrome, which had previously been treated with immunosuppressive therapy, manifesting with a crescendo transient ischemic attack because of left middle cerebral artery stenosis. Despite the administration of high doses of prednisolone and azathioprine for active Sjögren syndrome, the frequency of crescendo transient ischemic attacks increased with the progression of stenosis and magnetic resonance imaging showed the development of subacute cerebral infarction. Single-photon emission computed tomography with N-isopropyl[(123)I]-p-iodoamphetamine revealed apparent hemodynamic compromise in the affected cerebral hemisphere. In light of the increased risk of further progression of cerebral infarction, we decided to perform surgical revascularization in spite of her active inflammatory condition. The patient underwent extracranial-intracranial bypass without complications and was treated with intensive immunosuppressive therapy during the perioperative period. Based on our findings, we recommend surgical revascularization for occlusive cerebrovascular disease with hemodynamic compromise in combination with intensive immunosuppressive therapy, even in the active inflammatory state of autoimmune diseases, if ischemic symptoms are medically uncontrollable.
22526830 Thrombotic thrombocytopenic purpura with an autoantibody to ADAMTS13 complicating Sjögren 2013 Mar An association between thrombotic thrombocytopenic purpura (TTP) and Sjögren's syndrome (SS) is rare. This is the first report of two patients with TTP who had inhibitory autoantibodies to ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type 1 repeats) complicating primary SS. A rapid diagnosis of TTP, which is a potentially lethal condition, made it possible to treat the two cases successfully. Only eight similar cases with TTP complicating SS have been reported in the literature. The possible presentation of primary SS without classic sicca symptoms, but with haematological abnormalities including TTP, should be recognised. Furthermore, it is important to measure ADAMTS13 activity and anti-ADAMTS13 antibodies, because TTP with SS seems to be a concurrent overlapping autoimmune disorder. We suggest that plasma exchanges in combination with corticosteroids should be administered as early as possible, since they appeared to be effective in treating TTP with SS, including in our cases.
24885364 Anti-salivary gland protein 1 antibodies in two patients with Sjogren's syndrome: two case 2014 May 11 INTRODUCTION: Current diagnostic criteria for Sjogren's syndrome developed by the American College of Rheumatology include the presence of antinuclear antibodies, rheumatoid factor, anti-Ro or anti-La autoantibodies. The purpose of this report is to describe two patients with biopsy-proven Sjogren's syndrome lacking these autoantibodies but identified by antibodies to salivary gland protein 1. Diagnosis was delayed until salivary gland tumors developed in these patients because of the lack of the classic autoantibodies. This report emphasizes the existence of patients with primary Sjogren's syndrome who lack autoantibodies anti-Ro or anti-La and may therefore be misdiagnosed. Antibodies to salivary gland protein 1 identify some of these patients. CASE PRESENTATION: Two patients are described and were seen in the autoimmune disease clinics of the State University of New York (SUNY) at the Buffalo School of Medicine. In both patients, chronic dry mouth and dry eye had been dismissed as idiopathic because test results for autoantibodies anti-Ro and anti-La were negative. Both patients had swelling of major salivary glands that prompted biopsies. Biopsies of major salivary glands from both cases demonstrated salivary gland tumors and existence of inflammation consistent with Sjogren's syndrome. Serologic testing revealed antibodies to salivary gland protein 1. CONCLUSIONS: Patients presenting with classic clinical symptoms of dry mouth and eyes do not always show the current serologic markers of Sjogren's syndrome, anti-Ro and anti-La. In these cases, investigation for antibodies to salivary gland protein 1 is of importance to make the diagnosis of Sjogren's syndrome. Early diagnosis of Sjogren's syndrome is necessary for improved management as well as for vigilance regarding potential complications, such as salivary gland tumors as were seen in the described cases.
24397962 The role of M3 muscarinic acetylcholine receptor reactive T cells in Sjögren's syndrome: 2014 Jun CD4+ T cells constitute the majority of infiltrating cells in salivary glands and lachrymal glands of patients with Sjögren's syndrome (SS). The pathophysiology of SS involves T cell recognition of antigens through the T cell antigen receptor, which triggers cytokine production and chronic inflammation. The M3 muscarinic acetylcholine receptor (M3R) molecule is expressed in exocrine glands, such as salivary glands and lachrymal glands, and plays an important role in exocrine secretion. Previous studies indicated the presence of M3R reactive T cells in peripheral blood of 40% of patients with SS and autoantibodies against M3R in sera of 9-100% of the same patients. Thus, M3R is considered a candidate receptor for autoantigen recognition by T and B cells. The relationship between B cell epitopes and the function of anti-M3R antibodies has been reported, suggesting the pathogenic role of anti-M3R antibodies in xerostomia commonly seen in SS patients. We generated new experimental mouse model, M3R-induced sialadenitis (MIS), using Rag1(-/-) mice inoculated with splenocytes from M3R(-/-) mice immunized with M3R synthetic peptides. Mice with MIS developed severe SS-like sialadenitis. Cell transfer experiments using M3R(-/-)xIFNγ(-/-) mice and M3R(-/-)xIL-17(-/-) mice showed that IFNγ and IL-17 are key cytokines in the pathogenesis of sialadenitis. These findings indicate the crucial roles of M3R-reactive Th1 and Th17 cells in autoimmune sialadenitis, and suggest that these cells, in addition to anti-M3R antibodies, are potential targets in new treatments for SS.
23729799 Signal hyperintensities on brain magnetic resonance imaging in patients with primary Sjög 2013 Aug OBJECTIVE: To examine differences in number and size of signal hyperintensities (SH) on magnetic resonance imaging (MRI) between patients with primary Sjögren syndrome (pSS) and controls who all had frequent episodic tension-type headache (FETH), and to investigate their relation to platelet serotonin level (PSL), patient age, disease duration, and activity. METHODS: SH in 22 pSS patients with FETH were compared to 20 aged-matched controls with FETH, using the modified semiquantitative rating scale. Spectrofluorimetry was used for determination of PSL, and the European League Against Rheumatism SS Disease Activity Index (ESSDAI) for disease activity assessment. RESULTS: Statistically significant differences in the total number of SH were noted infratentorially (p = 0.025) and in the basal ganglia for lesions of diameter > 5 mm (p = 0.048). Significant correlations were found between disease duration and number of overall lesions > 5 mm (p = 0.04) and subcortical lesions of diameter 2-5 mm (p = 0.035). Number of periventricular SH inversely correlated to PSL (p = 0.019) and to patient age (p = 0.004), without association with markers of immunoinflammation and ESSDAI. CONCLUSION: Our study showed that SH on brain MRI are more common in specific regions of the brain in pSS patients with FETH than in controls with FETH, signifying a more widespread cerebral vasculopathy in SS patients with FETH. Periventricular SH seem to be associated to increased platelet serotonin release in pSS patients with FETH and correlated with disease duration, without correlation to the actual ESSDAI and markers of immunoinflammation, and might be linked with chronic immunoinflammation of low-grade intensity and vasculitis in pSS.
23123433 Polymicrobial and microsporidial keratitis in a patient using Boston scleral contact lens 2013 Apr AIM: To report a rare case of microsporidial and polymicrobial keratitis in a patient with Sjogren's syndrome and ocular cicatricial pemphigoid. METHOD: This is a descriptive case report. A 66-year-old lady diagnosed with Sjogren's syndrome (SS) and ocular cicatricial pemphigoid (OCP) presented to us with microbial keratitis after using a Boston sclera contact lens for a painful epithelial defect. After 9 days of medical treatment, she underwent therapeutic penetrating keratoplasty. RESULTS: 10% potassium hydroxide and calcofluor white wet mount revealed microsporidial spores. Gram positive cocci and Gram variable bacilli on Gram stain were identified as Staphylococcus epidermidis and Corynebacterium accolens in culture. Histopathological examination of the corneal tissue confirmed the presence of microsporidial spores. CONCLUSION: Microsporidal keratitis can occur in patients with severe ocular surface disease due to SS and OCP. Predisposing factors include dry eye, local and systemic immunosuppression and Boston scleral contact lens. Early surgical intervention may be needed to eradicate the infection.
24091004 Autoimmune animal models in the analysis of the CD47-SIRPα signaling pathway. 2014 Jan 15 Signal regulatory protein α (SIRPα), also known as SHPS-1/SIRPA, is an immunoglobulin superfamily protein that binds to the protein tyrosine phosphatases Shp1 and Shp2 through its cytoplasmic region and is predominantly expressed in dendritic cells and macrophages. CD47, a widely expressed transmembrane protein, is a ligand for SIRPα, with the two proteins constituting a cell-cell communication system. It was previously demonstrated that the CD47-SIRPα signaling pathway is important for prevention of clearance by splenic macrophages of red blood cells or platelets from the bloodstream. In addition, this signaling pathway is also implicated in homeostatic regulation of dendritic cells and development of autoimmunity. Here we describe the detailed protocols for methods that were used in our recent studies to study the role of the CD47-SIRPα signaling pathway in autoimmunity. We also demonstrate that hematopoietic SIRPα as well as nonhematopoietic CD47 are important for development of experimental autoimmune encephalomyelitis. Thus, we here strengthen the importance of experimental animal models as well as other methods for the study of molecular pathogenesis of autoimmunity.
23371349 Analgesic effect of the neuropeptide cortistatin in murine models of arthritic inflammator 2013 May OBJECTIVE: To investigate the role of the antiinflammatory neuropeptide cortistatin in chronic pain evoked by joint inflammation. METHODS: Thermal and mechanical hyperalgesia was evoked in mouse knee joints by intraplantar injection of tumor necrosis factor α and intraarticular infusion of Freund's complete adjuvant, and the analgesic effects of cortistatin, administered centrally, peripherally, and systemically, were assessed. In addition, the effects of cortistatin on the production of nociceptive peptides and the activation of pain signaling were assayed in dorsal root ganglion cultures and in inflammatory pain models. The role of endogenous cortistatin in pain sensitization and perpetuation of chronic inflammatory states was evaluated in cortistatin-deficient mice. Finally, the effect of noxious/inflammatory stimuli in the production of cortistatin by the peripheral nociceptive system was assayed in vitro and in vivo. RESULTS: Expression of cortistatin was observed in peptidergic nociceptors of the peripheral nociceptive system, and endogenous cortistatin was found to participate in the tuning of pain sensitization, especially in pathologic inflammatory conditions. Results showed that cortistatin acted both peripherally and centrally to reduce the tactile allodynia and heat hyperalgesia evoked by arthritis and peripheral tissue inflammation in mice, via mechanisms that were independent of its antiinflammatory action. These mechanisms involved direct action on nociceptive neurons and regulation of central sensitization. The analgesic effects of cortistatin in murine arthritic pain were linked to binding of the neuropeptide to somatostatin and ghrelin receptors, activation of the G protein subunit Gαi , impairment of ERK signaling, and decreased production of calcitonin gene-related peptide in primary nociceptors. CONCLUSION: These findings indicate that cortistatin is an antiinflammatory factor with potent analgesic effects that may offer a new approach to pain therapy in pathologic inflammatory states, including osteoarthritis and rheumatoid arthritis.
23303559 Differential regulation of HIF-mediated pathways increases mitochondrial metabolism and AT 2013 Apr Inappropriate osteoclast activity instigates pathological bone loss in rheumatoid arthritis. We have investigated how osteoclasts generate sufficient ATP for the energy-intensive process of bone resorption in the hypoxic microenvironment associated with this rheumatic condition. We show that in human osteoclasts differentiated from CD14(+) monocytes, hypoxia (24 h, 2% O2 ): (a) increases ATP production and mitochondrial electron transport chain activity (Alamar blue, O2 consumption); (b) increases glycolytic flux (glucose consumption, lactate production); and (c) increases glutamine consumption. We demonstrate that glucose, rather than glutamine, is necessary for the hypoxic increase in ATP production and also for cell survival in hypoxia. Using siRNA targeting specific isoforms of the hypoxia-inducible transcription factor HIF (HIF-1α, HIF-2α), we show that employment of selected components of the HIF-1α-mediated metabolic switch to anaerobic respiration enables osteoclasts to rapidly increase ATP production in hypoxia, while at the same time compromising long-term survival. We propose this atypical HIF-driven metabolic pathway to be an adaptive mechanism to permit rapid bone resorption in the short term while ensuring curtailment of the process in the absence of re-oxygenation.