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(1/82) Macrophages and dendritic cells in IRBP-induced experimental autoimmune uveoretinitis in B10RIII mice.

PURPOSE: To investigate the characteristics of the mononuclear cell infiltrate in murine experimental autoimmune uveoretinitis (EAU). METHODS: EAU was induced by immunization with bovine interphotoreceptor retinal binding protein (IRBP) in Freund's complete adjuvant (subcutaneous injection) and pertussis toxin (intraperitoneal injection) in B10RIII mouse. Then animals were killed on days 7, 9, 12, 15, 20, 26, and 39 after immunization. Eyes were processed for hematoxylin and eosin staining to characterize the disease and to assess the severity and extent of the EAU. Single and dual immunohistochemical staining in various combinations with monoclonal antibodies against CD45, CD4, CD8, major histocompatibility complex (MHC) class II, CD11c, NLDC-145, and a variety of macrophage markers was performed. RESULTS: The authors' results showed that vitritis, vasculitis and perivasculitis, retinal detachment, and granuloma formation in retina and choroid were the predominant features of IRBP-induced B10RIII mice EAU. Immunohistologic results showed that CD4+ T cells and macrophages were the main infiltrating cells in retina and choroid throughout the entire course of the disease. MHC class II negative macrophages expressing antigens reacting with MOMA-2, F4/80, sialoadhesin, and CD11b were prominent during the peak phase of tissue damage in the retina and choroid. Dendritic cells (DCs) characterized by dual positivity for MHC class II and CD11c and negative for sialoadhesin appeared at time of disease onset and continued to be recruited during the inflammatory process. DCs at the site of inflammation were NLDC-145 weak and CD8 negative, indicating that they were of the myeloid rather than the lymphoid lineage. CONCLUSIONS: The results suggest that EAU in B10RIII mice is initiated by local-infiltrating, dendritic antigen-presenting cells, whereas tissue damage is associated with sialoadhesin-positive, phagocytic nonantigen-presenting macrophages during the effector stage.  (+info)

(2/82) Characterisation of uveitis in patients with psoriatic arthritis.

OBJECTIVE: The purpose of this study is to describe the clinical characteristics of uveitis related to psoriatic arthritis (PsA), and also to compare the uveitis in PsA to the uveitis in spondyloarthropathy (SA). METHODS: Sixteen patients with uveitis and PsA were evaluated in a tertiary care uveitis clinic. These patients were compared retrospectively to a series of 89 patients with uveitis and SA. RESULTS: Eight (50%) of the 16 patients with uveitis had strictly peripheral arthritis, while two (12.5%) had axial only, and six (37.5%) had axial and peripheral arthritis. Patients with uveitis and axial disease were more likely to be male (100% v 38%) and HLA-B27 positive (6 of 6 typed positive v 0 of 3 typed positive) when compared with those with uveitis and peripheral arthritis only. Compared with patients with SA, those with PsA were more likely to have insidious onset (19% v 3%), simultaneously bilateral (37.5% v 7%), chronic duration (31% v 6%), or posterior (44% v 17%) uveitis. Complications of uveitis were similar in the SA and PsA groups. CONCLUSION: Uveitis in patients with PsA was more likely to be insidious in onset, continuous, posterior, and active bilaterally compared with uveitis in patients with SA. Patients with uveitis and axial involvement were more likely to be male and HLA-B27 positive compared with patients with uveitis and peripheral arthritis alone. Patients with seronegative arthritis and uveitis that begins insidiously, lasts longer than six months, is bilateral, or is posterior, should be carefully questioned about the presence of either psoriasis or inflammatory bowel disease.  (+info)

(3/82) CD69 expression on peripheral CD4+ T cells parallels disease activity and is reduced by mycophenolate mofetil therapy in uveitis.

PURPOSE: To assess the effects of mycophenolate mofetil (MMF) therapy on T helper cell activation status, using CD69 expression and cytokine profile with flow cytometry in relation to clinical activity in uveitis. METHODS: Patients with posterior or intermediate uveitis treated with MMF (n = 10), patients with active uveitis not treated with MMF and receiving no or minimal therapy (n = 10), and healthy volunteers (n = 21) had peripheral blood lymphocyte immunofluorescence analysis for T helper cell (CD4, CD3) markers, activation status (CD69), and intracellular cytokine (interleukin [IL]-2, interferon [IFN]-gamma, and IL-4) levels. Patients were compared before and during MMF therapy in relation to T helper cell activation and clinical activity. RESULTS: Patients with active uveitis not treated with MMF and receiving no or minimal therapy had increased frequency of CD69-positive CD4 T cells (10.5% +/- 4.6%, P = 0.0007) compared with healthy volunteers (3.3% +/- 2.7%). Of all patients receiving MMF therapy, only patients with moderate to severe uveitis activity in the pre-MMF treatment group (n = 5; 15.5% +/- 5.0%, P = 0.004) had increased frequency of CD69-positive CD4 T cells compared with healthy volunteers. During MMF therapy, a significant reduction in frequency of CD69-positive CD4 T cells occurred in patients with prior moderate to severe uveitis activity (to 8.9% +/- 3.8%, P = 0.04). Levels of CD69-positive CD4 T cells in patients who had had inactive or mildly active disease (n = 5) before and during MMF therapy were comparable with levels in healthy volunteers. No significant changes in cytokine levels were found between the patient and control groups. A significant association between changes in frequency of CD69-positive CD4 T cells and changes in visual acuity (P = 0.008) and changes in vitreal haze (binocular indirect ophthalmoscopy score; P = 0.01) was observed in MMF-treated patients with prior moderate to severe uveitis activity. CONCLUSIONS: Reduction in uveitis activity during MMF therapy correlates with reduction in frequency of peripheral blood CD69-positive CD4 cells. The frequency of CD69-positive CD4 T cells is a measure of activity in posterior uveitis and may guide adequate immunosuppression.  (+info)

(4/82) Syphilitic posterior uveitis: correlative findings and significance.

Twenty-one patients with syphilitic posterior uveitis were investigated retrospectively to study the disease spectrum, associations with neurosyphilis, and therapeutic implications. Ophthalmologic manifestations of syphilitic posterior uveitis are differentiated into acute and chronic uveitides. The several distinct acute uveitic syndromes are usually florid and are associated with early syphilis, with VDRL-positive syphilitic meningitis, and frequently with human immunodeficiency virus coinfection. The chronic posterior uveitides are often insidious, a manifestation of late syphilis, and associated commonly with subclinical neurosyphilis. All patients with acute cases and 54% of patients with chronic cases in our study received penicillin therapy appropriate for neurosyphilis. The frequent association of syphilitic posterior uveitis with neurosyphilis and the analogous spirochetal sequestration beyond the blood-brain and the blood-ocular barriers suggest that all patients with syphilitic posterior uveitis, irrespective of ocular disease intensity, should undergo evaluation of cerebrospinal fluid and be treated with penicillin regimens appropriate for neurosyphilis.  (+info)

(5/82) High dose intravenous steroid therapy for severe posterior segment uveitis in Behcet's disease.

AIM: To evaluate the safety and effectiveness of high dose intravenous steroid therapy (HDIST) in Behcet's disease patients with severe posterior segment uveitis attacks. METHODS: Five patients with ocular Behcet's disease were treated with HDIST for severe posterior segment attacks. Two patients had vasculitis, one patient had papillitis, and the other two had retinitis; four patients also had accompanying severe vitritis. The visual acuities and improvement in ocular signs after HDIST were evaluated. RESULTS: During HDIST, patients had no systemic complications caused by treatment. All patients responded to HDIST with evidence of a decrease in intraocular inflammatory activity and improved visual acuities within a mean time of 7 (1-15) days of commencing treatment. During follow up three out of five patients had new posterior segment attacks. CONCLUSION: HDIST is effective in controlling severe, vision threatening acute posterior segment Behcet's uveitis attacks and in improving visual function in a short period of time  (+info)

(6/82) Leukocyte trafficking in experimental autoimmune uveitis: breakdown of blood-retinal barrier and upregulation of cellular adhesion molecules.

PURPOSE: To clarify the order of events occurring in the breakdown of the blood-retinal barrier (BRB) in experimental autoimmune uveoretinitis (EAU) and in particular to study the relationships between increased vascular permeability, upregulation of endothelial cell adhesion molecules, and leukocyte adhesion and infiltration during EAU. METHODS: B10.RIII mice were immunized with human interphotoreceptor retinoid binding protein (IRBP) peptide 161-180. Changes in the retinal microvasculature were examined on days 3, 6, 7, 8, 9, 10, 16, and 21 postimmunization (pi). Evans blue dye was administered intravenously to assess vascular permeability. Expression of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, P-selectin, E-selectin, and platelet endothelial cell adhesion molecule (PECAM)-1 was evaluated by in vivo administration of antibody and subsequent immunostaining of retinal wholemounts. Lymphocytes from inguinal lymph nodes of normal and chicken ovalbumin (OVA)- or IRBP peptide-immunized mice at day 5, 6, 7, 8, and 15 pi were labeled in vitro with calcein-AM (C-AM) and infused intravenously into syngeneic recipient mice, which had been immunized with peptide at the same corresponding time point. Wholemount preparations of retinas were observed 24 hours later by confocal microscopy to determine the adhesion and infiltration of lymphocytes. RESULTS: The first observation of an increase in vascular permeability occurred at day 7 pi and was restricted to focal areas of the retinal postcapillary venules of the inner vascular plexus. This progressively extended to the outer vascular plexus at day 9 pi. Specific adhesion of leukocytes to the endothelium of retinal venules of the inner vascular plexus was first observed at day 6 pi. Leukocyte extravasation into the retinal parenchyma from these vessels began at day 8 pi and extended to the outer vascular plexus at day 9 pi. The expression of adhesion molecules increased progressively during the development of EAU. In particular, the adhesion molecules ICAM-1, P-selectin, and E-selectin were expressed predominately in retinal venules, the sites of BRB breakdown, cell adhesion, and extravasation, from day 7 pi. The increases in expression of ICAM-1 and P-selectin were associated both spatially and temporally with breakdown of the BRB, cell adhesion, and extravasation. No increase in expression of P-selectin and ICAM-1 was observed in either the mesenteric vessels of EAU mice or the retinal vessels of OVA-immunized mice. CONCLUSIONS: The sequence of events in EAU appears to be focal adhesion of leukocytes to discrete sites on postcapillary venules, followed by upregulation of adhesion molecules, especially ICAM-1 and P-selectin, and breakdown of the BRB, leading to transendothelial migration of leukocytes and recruitment of large numbers of cells to the retinal parenchyma. These changes occur over a short period of 6 to 9 days pi and initiate the process of tissue damage during the following 2 to 3 weeks.  (+info)

(7/82) Human recombinant interferon alfa-2a for the treatment of Behcet's disease with sight threatening posterior or panuveitis.

BACKGROUND: Behcet's disease is a multisystem vasculitis of unknown origin. Standard treatment mainly comprises systemic immunosuppressive agents. Ocular involvement, mostly posterior uveitis with retinal vasculitis, leads to blindness in 20-50% of the involved eyes within 5 years. The efficacy of interferon alfa-2a was studied in patients with sight threatening posterior uveitis or retinal vasculitis. METHODS: 50 patients were included in this open, non-randomised, uncontrolled prospective study. Recombinant human interferon alfa-2a (rhIFNalpha-2a) was applied at a dose of 6 million units subcutaneously daily. Dose reduction was performed according to a decision tree until discontinuation. Disease activity was evaluated every 2 weeks by the Behcet's disease activity scoring system and the uveitis scoring system. RESULTS: Response rate of the ocular manifestations was 92% (three non-responder, one incomplete response). Mean visual acuity rose significantly from 0.56 to 0.84 at week 24 (p<0.0001). Posterior uveitis score of the affected eyes fell by 46% every week (p<0.001). Remission of retinal inflammation was achieved by week 24. Mean Behcet's disease activity score fell from 5.8 to 3.3 at week 24 and further to 2.8 at week 52. After a mean observation period of 36.4 months (range 12-72), 20 patients (40%) are off treatment and disease free for 7-58 months (mean 29.5). In the other patients maintenance IFN dosage is three million units three times weekly. CONCLUSIONS: rhIFNalpha-2a is effective in ocular Behcet's disease, leading to significant improvement of vision and complete remission of ocular vasculitis in the majority of the patients.  (+info)

(8/82) Contribution of TNF-alpha to leukocyte adhesion, vascular leakage, and apoptotic cell death in endotoxin-induced uveitis in vivo.

PURPOSE: To investigate the effect of TNF-alpha on leukocyte adhesion, vascular leakage, and apoptotic cell death in endotoxin-induced uveitis (EIU) in the rat. METHODS: EIU was induced in Long-Evans rats by a single footpad injection of lipopolysaccharide (LPS; 350 microg/kg) from Salmonella typhimurium. A single injection of recombinant TNF receptor P75 (etanercept) was given subcutaneously 24 hours before the administration of LPS. Twenty-four hours after administration of LPS, leukocyte adhesion was evaluated in vivo with SLO-acridine orange angiography and ex vivo with concanavalin A lectin staining of retinal flatmounts. Neutrophil activation was quantified by a myeloperoxidase activity assay. Vascular leakage was assessed by Evans blue extravasation. Retinal cell death was assessed with TUNEL staining and quantified with a modified ELISA protocol. Involvement of caspase-3 and -8 was determined by M30 antibody staining, Western blot analysis, and a test for enzymatic activity. RESULTS: Twenty-four hours after the LPS injection, significant increases in leukocyte rolling, adhesion, and activation were observed. In addition, increased levels of apoptosis in the vascular endothelium and the ganglion cell and inner nuclear layers and activation of caspase-8 and -3 were observed. After administration of the TNF-alpha inhibitor, significant reduction in the leukocyte rolling, adhesion, activation, and apoptosis in all the affected layers was observed. The quantitative analysis of vascular leakage revealed a significant decrease after treatment with etanercept. Retinal cell death quantification showed a significant decrease after treatment with the TNF-alpha inhibitor. CONCLUSIONS: Anti-TNF-alpha treatment reduces the LPS-induced increases in leukocyte rolling, adhesion, and vascular leakage in this rat model of inflammatory uveitis. These results suggest the involvement of TNF-alpha in inflammatory uveitis and its potential use as a therapeutic agent in the reduction of ocular inflammation.  (+info)