http://repub.eur.nl/res/aut/4716/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/38970/ 2013-02-15T00:00:00Z Rationale: Recent observations of abnormal immunoglobulin responses and case reports describing successful B-cell ablative therapy suggest involvement ofBcells in the pathogenesis of sarcoidosis. Objectives: To investigate how abnormal B-cell maturation and function in patients with sarcoidosis contribute to disease. Methods: Patients with sarcoidosis (n = 32) were included for detailed analysis by immunohistochemistry of tissue, flow cytometry of blood B-cell subsets, andserumimmunoglobulin levels.Vaccinationresponses in patients with sarcoidosis to influenza virus and encapsulated bacteria andmolecular analysis ofimmunoglobulin heavy chain transcriptswere studied for functional analysis of immunoglobulin responses. Measurements and Main Results: Perigranuloma localization of IgAproducing plasma cells and numerous B cells were found in affected tissues. Total blood B-cell numbers were normal, CD271 memory B cells were significantly reduced, and CD272IgA1 B cells were significantly increased; the results are normalized in patients treated with TNF-ablockers.Despitethis,patientshadnormal serumimmunoglobulin levels and normal antigen-specific immunoglobulin responses. IgAand IgGtranscripts, however, showed highfrequencies of somatic hypermutations and increased usage of downstream IgG subclasses, suggestive for prolonged or repetitive responses. Conclusions: The large B-cell infiltrates in granulomatous tissue and increased molecular signs of antibody maturation are indicative of direct involvement of B cells in local inflammatory processes in patients with sarcoidosis. Moreover, CD272IgA1 B cells could be a marker for treatment with TNF-a blockers. These findings of B cells as emerging key players provide a rationale for a systematic study on B-cell ablative therapy in patients with sarcoidosis. Copyright http://repub.eur.nl/res/pub/39252/ 2012-06-15T00:00:00Z Seasonal hyperacute panuveitis (SHAPU) is a potentially blinding ocular disease occurring in Nepal that principally affects young children. Random amplification of partially purified vitreous fluid (VF)-derived nucleic acid revealed the presence of human anelloviruses in VF of SHAPU patients. In a comparative study of patients with different ocular pathologies, SHAPU patients were at highest risk of harboring anelloviruses in their eyes. The majority of SHAPU patients had multiple anelloviruses in their VF. The ocular anellovirus load in SHAPU and non-SHAPU patients did not differ and no SHAPU-specific anellovirus variant was detected. Analysis of paired serum and VF samples from SHAPU and non-SHAPU patients showed that the anellovirus detected in VF samples most likely originated from the systemic viral pool during viremia, potentially through breakdown of the blood-ocular barrier. The detection of anelloviruses in VF samples of uveitis patients, profoundly so in SHAPU patients, is imperative and warrants elucidation of its clinical significance. © 2012 The Author. http://repub.eur.nl/res/pub/26304/ 2011-06-01T00:00:00Z Background/aims: The neonatal Fc receptor (FcRn) protects immunoglobulin G (IgG) from catabolism, controls its transport between cell layers and extends its serum half-life. In the human, vitreous IgG can be found, but how vitreous IgG is processed or transported is currently unknown. The FcRn is a candidate molecule to regulate these processes. The authors examined FcRn expression and regulation in human retinal pigment epithelium (RPE) cells. Methods: In three primary RPE cell cultures (from three donor eyes) and in the human RPE cell line ARPE-19, FcRn and beta-2-microglobulin (β2M) mRNA levels were determined by real-time quantitative PCR. FcRn protein expression was analysed by western blot studies. Stimulation experiments were performed with recombinant human tumour necrosis factor (TNF)-α and interferon (IFN)-γ. HT-29, THP-1 and HeLa cell lines were used as FcRn positive and negative non-ocular controls, respectively. Results: Expression of FcRn mRNA and protein was demonstrated in all three RPE cultures. After stimulation with TNF-α, FcRn expression is downregulated in RPE cells and upregulated in HT-29 and THP-1 cells. IFN-γ has no effect on FcRn expression in RPE cells. Conclusions: Human RPE cells express FcRn. The proinflammatory cytokine TNF-α downregulates FcRn expression. The authors speculate that the FcRn may play a pivotal role in the immune privilege of the human eye. http://repub.eur.nl/res/pub/25298/ 2009-02-01T00:00:00Z PURPOSE. Varicella zoster virus (VZV)-induced retinitis is characterized by the presence of virus-infected cells in the retinal layer and the ocular infiltration of VZV-specific T cells. Herein, the susceptibility of human retinal pigment epithelial (RPE) cells to VZV infection and the ability of virus-specific CD4+T cells to control VZV infection in RPE cells in vitro is addressed. METHODS. Human primary RPE cell cultures (n = 2) were infected with a VZV strain expressing green fluorescent protein. The infection and viability of infected RPE cells was monitored by flow cytometry or by a fluorescent imager on RPE monolayers. RPE cells, pretreated with or without interferon-γ (IFN-γ), were infected with VZV and subsequently cultured with VZV-specific CD4+T-cell clones (TCCs; n = 3) recognizing disparate VZV proteins presented by different HLA class II alleles. IFN-γ production and cytotoxicity of the TCCs in response to VZV-infected RPE cells was determined by flow cytometry. RESULTS. Human RPE cells are permissive to a productive VZV infection. VZV-infected RPE cells presented the cognate antigen to the CD4+TCCs only if the RPE cells were pretreated with IFN-γ and expressed the appropriate HLA class II allele. VZV-specific TCCs inhibited productive VZV infection in RPE cells, which was in part attributed to TCC-mediated killing of the VZV-infected RPE cells. CONCLUSIONS. The results presented suggest that RPE cells may play a role as retina-resident antigen-presenting cells in the intraocular, VZV-specific, T cell-mediated inflammatory response of VZV-induced uveitis. http://repub.eur.nl/res/pub/35089/ 2007-12-01T00:00:00Z Purpose: To report on the efficacy of the somatostatin analog octreotide long-acting repeatable (LAR), in the treatment of uveitic chronic macular edema (CME). Design: Case series, retrospective analysis. Methods: In 20 patients, 20 episodes of recurrent CME during otherwise quiescent uveitis were treated with intramuscular octreotide LAR injections. Patients were included if CME control with acetazolamide or systemic and periocular steroids had failed during previous CME episodes or if contraindications existed for persistent use of these therapies. Mean outcome points were CME and visual acuity changes. Correlation of prognostic factors with these outcomes was analyzed. Results: The included CME episodes occurred 7.6 ± 1.4 years after onset of uveitis. Octreotide LAR treatment started 7.0 ± 7.3 months after diagnosis of CME. CME decreased in 70% of episodes, after 2.7 ± 1.3 months of treatment. After arrest of successful treatment, CME recurred instantly (27.2%) or within six months (36.4%). In 36.4% of successfully treated episodes, CME was absent for more than one year. A probable prognostic factor for success was the duration of CME before treatment. Conclusions: Octreotide LAR had an edema-reducing effect in 70% of treated CME episodes. Successful response was related to duration of CME before start of treatment. The early recurrence of CME (63.6%) after arrest of octreotide LAR advocates a long-term treatment in recent episodes of macular edema in otherwise quiescent uveitis. http://repub.eur.nl/res/pub/35758/ 2007-08-01T00:00:00Z PURPOSE. Varicella zoster virus (VZV) is a common cause of infectious uveitis associated with an intraocular inflammatory response involving virus-specific T cells. In the current study, the functional characteristics and the antigen specificity of VZV-reactive T cells recovered from intraocular fluid (IOF) samples of five patients with VZV were determined. METHODS. B-cell lines were infected with a comprehensive panel of recombinant vaccinia viruses expressing 11 individual VZV open reading frames (ORFs), or alternatively pulsed with the corresponding peptides to generate antigen-presenting cells (APCs). T-cell responsiveness of the IOF-derived VZV-specific T cells toward APCs was monitored by interferon (IFN)-γ enzyme-linked immunosorbent spot-forming assays on bulk T-cell cultures and subsequently T-cell clones (TCCs). The cytokine-secretion profile and cytotoxicity of the VZV-specific TCCs was determined by ELISA and flow cytometry, respectively. RESULTS. T-cell reactivity to VZV proteins encoded by ORF4, -10, -14, -18, -29, -31, -61, -62, -63, -67, and -68 was demonstrated, but specificity varied individually. T-cell epitopes on ORF62 and -68 were delineated. The TCCs secreted IFNγ, but relatively low levels of interleukin-4 and -5, in response to VZV antigen-expressing APCs. The TCCs induced antigen-specific cytotoxic T-cell activity. CONCLUSIONS. The results suggest that the intraocular VZV-specific T-cell response in the patients with VZV analyzed is directed to a broad spectrum of VZV antigens, including the latency-associated VZV proteins from ORFs 4, 29, 63, and particularly ORF62. This local T-cell response was in part mediated by cytotoxic CD4+T cells with a Th1/0-like effector memory phenotype. Copyright http://repub.eur.nl/res/pub/35489/ 2007-04-01T00:00:00Z http://repub.eur.nl/res/pub/13782/ 2005-05-01T00:00:00Z AIM: To describe the effect of additional treatment with anti-TNF-alpha therapy in a case series of 13 patients with serious sight threatening uveitis. METHODS: 13 patients with serious sight threatening uveitis were included, of whom six had Behcet's disease, five had idiopathic posterior uveitis, one had sarcoidosis, and one birdshot retinochoroiditis. Onset and course of ocular inflammation, inflammatory signs, and visual acuity were assessed. Patients were treated with 200 mg (approximately 3 mg/kg) infliximab infusion. Repeat infusions were given based on clinical response. RESULTS: Infliximab treatment resulted in an effective suppression of ocular inflammation in all patients. In patients with non-Behcet's disease uveitis visual acuity in six out of eight improved or was stable. In patients with Behcet's disease visual acuity in five out of six improved or was stable. CONCLUSION: Anti-TNF-alpha treatment may be of value in the treatment of uveitis, and in patients with Behcet's disease, leading to suppression of ocular inflammation, vasculitis, and improvement of vision in the majority. Based on these results a controlled masked study is warranted. http://repub.eur.nl/res/pub/10278/ 2004-01-01T00:00:00Z AIM: To evaluate the possibility of translocating autologous peripheral retinal pigment epithelial (RPE) cells and enhance their adhesion to improve functional outcome after choroidal neovascular membrane extraction in patients with subfoveal neovascular membranes. METHODS: A prospective, non-controlled surgical study in eight consecutive patients operated between February and July 2001 with final data monitoring in July 2002. All patients had mixed subfoveal membranes of 2-4 disc diameters. Functional tests included Snellen vision and central fixation testing. During vitrectomy, after the extraction of the neovascular complex, 8 x 10(4)-16 x 10(4) RPE cells were removed from the periphery and translocated under the macula following the submacular injection of 2 microg of poly-L-lysine to promote adhesion of the cells. RESULTS: With a follow up ranging from 3 months to 16 months, a pigmented area was seen in the extraction bed of the neovascular membrane in only one patient. Fixation was at the edge of the extraction bed in three patients. Vision remained the same in five patients and deteriorated in three (all with retinal detachment). Retinal detachment due to proliferative vitreoretinopathy occurred in three patients. CONCLUSIONS: The translocation of autologous peripheral RPE cells after membrane extraction was technically possible in a sterile manner, but was associated with a high proliferative vitreoretinopathy rate and in the present series had no measurable positive effect on functional outcome. http://repub.eur.nl/res/pub/3881/ 2002-09-01T00:00:00Z The phenotype and antigen-specificity of T cells expanded by mitogenic stimulation from intra-ocular fluid (IOF) samples of affected eyes of six Behçet's disease (BD) patients, and seven patients with other uveitis entities, were determined. High numbers of γδ T cells, predominantly Vγ9Vδ2 T cells, were only detected in the IOF-derived TCL of three BD patients. Whereas no TCL responded to heat shock protein (HSP) 65 kDa, reactivity to isopentyl pyrophosphate (IPP) and related non-peptide prenyl pyrophosphates (PPP) was restricted to the γδ T cell containing TCL. Upon IPP stimulation, these TCL secreted IFN-γ but no IL-4. By single-cell analysis of intracellular IFN-γ production and CD69 expression the IOF-derived IPP-specific T cells were identified as CD4−CD8− γδ T cells. The data presented suggest the infiltration of PPP-specific Vγ9Vδ2 Th1-like cells into the eye of BD patients with uveitis. http://repub.eur.nl/res/pub/9421/ 2000-01-01T00:00:00Z PURPOSE: The growth of ocular neovascularization is regulated by a balance between stimulating and inhibiting growth factors. Somatostatin affects angiogenesis by inhibiting the growth hormone-insulin-like growth factor axis and also has a direct antiproliferative effect on human retinal endothelial cells. The purpose of our study is to investigate the expression of somatostatin receptor (sst) subtypes and particularly sst subtype 2A (sst2A) in normal human macula, and to study sst2A in different stages of age-related maculopathy (ARM), because of the potential anti-angiogenic effect of somatostatin analogues. METHODS: Sixteen eyes (10 enucleated eyes, 4 donor eyes, and 2 surgically removed choroidal neovascular [CNV] membranes) of 15 patients with eyes at different stages of ARM were used for immunohistochemistry. Formaldehyde-fixed paraffin-embedded slides were incubated with a polyclonal anti-human sst2A antibody. mRNA expression of five ssts and somatostatin was determined in the posterior pole of three normal human eyes by reverse transcriptase-polymerase chain reaction. RESULTS: The immunohistochemical expression of sstA in newly formed endothelial cells and fibroblast-like cells was strong in fibrovascular CNV membranes. mRNA of sst subtypes 1, 2A, and 3, as well as somatostatin, was present in the normal posterior pole; sst subtypes 4 and 5 were not detectable. CONCLUSIONS: Most early-formed CNV in ARM express sst2A. The presence of mRNA of sst subtype 2A was observed in normal human macula, and subtypes 1 and 3 and somatostatin are also present. sst2A receptors bind potential anti-angiogenic somatostatin analogues such as octreotide. Therefore, somatostatin analogues may be an effective therapy in early stages of CNV in ARM. http://repub.eur.nl/res/pub/9527/ 2000-01-01T00:00:00Z http://repub.eur.nl/res/pub/9188/ 1999-01-01T00:00:00Z AIM: To investigate the effect of additional oral vitamins C and E on acute anterior uveitis. METHODS: A placebo controlled double masked study on the effect of vitamin C 500 mg in combination with vitamin E 100 mg twice daily in 145 patients with acute anterior uveitis. As a primary end point variable, laser cell/flare measurements were performed. Best corrected and stenopeic visual acuity (VA) testing and clinical variable scores were measured. RESULTS: Laser flare measurements (ph/s) before treatment were 207.1 (SD 258) in the vitamin group and 143.6 (156) in the placebo group. After 3 days corresponding values were 80.2 (129) and 54.7 (82), after 7 days 89.2 (187) (12.5) and 85.8 (208), after 14 days 47.1 (109.5) and 40.5 (116) after 28 days 23.1 (53.6) and 23.1 (48), and after 56 days 15.6 (26) and 15.3 (17). There was no significant difference in time trend between the two treatment groups (RMANOVA; p = 0.53). Baseline VA (logMAR) was 0.106 (0.241) in the vitamin group and 0.128 (0.456) in the placebo group. VA after 3 days was 0. 236 (0.293) and 0.344 ( 0.489), after 7 days 0.204 (0.292) and 0.292 (0.479), after 14 days 0.162 (0.274) and 0.193 (0.454), after 28 days 0.096 (0.232) and 0.158 (0.436), and 0.026 (0.213) and 0.106 (0. 437) after 56 days. Although no significant difference in time trend was detected, evaluation of the VA data of the last time point (56 days) by means of the Mann-Whitney test showed a significantly better VA in the vitamin group (p = 0.01). CONCLUSIONS: There was no significant effect of vitamins C and E on laser flare measurements. The significant effect of the oral vitamins on visual acuity at 8 weeks after start of the oral vitamins C and E may indicate a protective effect in patients with acute anterior uveitis. http://repub.eur.nl/res/pub/8845/ 1998-01-01T00:00:00Z BACKGROUND/AIMS: Earlier studies on intraocular tissue have demonstrated that T lymphocytes play a major role in the pathogenesis of uveitis. Adhesion molecules are immunoregulatory molecules for the interaction between T lymphocytes and vascular endothelium and they play an important role in the recruitment of specific T lymphocytes from the circulation into inflamed tissue. In uveitis an increased expression of some of these adhesion molecules may be expected. METHODS: The presence of adhesion molecules was investigated in iris biopsy specimens from 11 patients with uveitis and eight controls (patients with primary open angle glaucoma) immunohistochemically with a panel of monoclonal antibodies: LECAM (CD 62L), ICAM-1 (CD 54), LFA-1 (CD 11a/18), VCAM-1 (CD 106), VLA-4 (CD 49d), and HECA-452, a marker for high endothelial venules. RESULTS: Positive staining for ICAM-1, LFA-1 and VCAM-1 was found in the iris in a significantly higher number of uveitis patients than in controls. The remaining adhesion molecules were also found in a higher number of uveitis patients than in controls, but this difference did not reach statistical significance. CONCLUSION: An increased expression of adhesion molecules was found in the iris of patients with uveitis, indicating an immunoregulatory function for adhesion molecules in the pathogenesis of uveitis.