 |
|
Early Effects of Intravitreal Triamcinolone Acetonide on Inflammation and Proliferation in Human Choroidal Neovascularization
Olcay Tatar, MD;
Annemarie Adam, MTA;
Kei Shinoda, MD, PhD;
Edwin Kaiserling, MD;
Vicky Boeyden, MD;
Carl Claes, MD;
Claus Eckardt, MD;
Tillmann Eckert, MD;
Grazia Pertile, MD;
Gabor B. Scharioth, MD;
Efdal Yoeruek, MD;
Peter Szurman, MD;
Karl Ulrich Bartz-Schmidt, MD;
Salvatore Grisanti, MD
Arch Ophthalmol. 2009;127(3):275-281.
ABSTRACT
Objective To evaluate the early effects of triamcinolone acetonide (TA) on inflammation, proliferation, and vascular endothelial growth factor (VEGF) in human choroidal neovascularization (CNV).
Methods Retrospective review of an interventional case series of 29 patients who underwent macular translocation. Fourteen CNV membranes without previous therapy (control CNV group) and 4 CNV membranes excised 3 days after photodynamic therapy (PDT CNV group) comprised the control groups. Eleven patients were treated with intravitreal TA (TA CNV group; n = 5) or PDT and TA combined (PDT+TA CNV group; n = 6) 3 to 9 days preoperatively. The CNV membranes were stained for cytokeratin 18, CD34, VEGF, intercellular adhesion molecule-1 (ICAM-1), E-selectin, CD68, CD45, Ki-67, and Thy-1.
Results Treatment with TA and PDT+TA resulted in increased immunostaining of ICAM-1 in endothelial cells and the stroma and a higher percentage of Thy-1 expression than controls. The density of macrophages was significantly increased in PDT+TA CNV membranes. Leukocyte density and proliferative activity were lower in TA and PDT+TA CNV membranes. The total VEGF score was significantly increased in TA and PDT+TA CNV membranes compared with the control CNV membranes. Evidence of VEGF in the retinal pigment epithelium of PDT+TA CNV membranes was stronger than in control CNV membranes.
Conclusions Triamcinolone acetonide has no inhibitory effect on macrophage infiltration or ICAM-1, Thy-1, or VEGF expression in CNV membranes in the early term. The clinical benefits of TA are probably not based on pure antiinflammatory or VEGF-suppressing mechanisms.
INTRODUCTION
Neovascular age-related macular degeneration (AMD) is the leading cause of visual disability in the elderly population in industrialized countries.1 Ocular verteporfin photodynamic therapy (PDT) is an established treatment modality.2 However, a high recurrence rate compromises its success.2 Pilot studies, therefore, combine PDT with adjuvants to overcome these limitations. Intravitreal triamcinolone acetonide (TA), either alone or in combination with PDT, appears to be beneficial in neovascular AMD treatment, especially in reducing the PDT retreatment rate.3-4
Triamcinolone acetonide mediates antiangiogenic, antiinflammatory, and antipermeability effects.5-21 Vascular endothelial growth factor (VEGF) is a major stimulator of choroidal neovascularization (CNV).22 The antiangiogenic action of TA was supposed to be due to decreased VEGF expression, either directly16-21 or indirectly, through its antiinflammatory effects.8, 10, 13-15
However, VEGF expression was not decreased in human CNV membranes excised after TA monotherapy or PDT+TA combination therapy.23 Because VEGF expression in CNV was found to be correlated with inflammatory cell infiltration, this study was undertaken to evaluate the early effects of intravitreal TA, either as monotherapy or as an adjuvant to PDT, on inflammation and proliferation in human CNV membranes. Expression of CD34, cytokeratin 18, and Ki-67 were used to identify endothelial cells (EC), retinal pigment epithelium (RPE), and proliferating cells, respectively. Inflammation was evaluated by expression of cellular adhesion molecules, namely intercellular adhesion molecule 1 (ICAM-1) and E-selectin, density of CD45 and CD68 immunoreactive inflammatory cells, and expression of Thy-1. Expression of CD45 was greater on blood-borne infiltrating leukocytes and monocytes rather than resident macrophages that express CD68.24-25 Thy-1 is a cell surface marker expressed on vascular EC that is upregulated by inflammatory cytokines interleukin (IL)–1β and tumor necrosis factor (TNF)– , but remains unaffected by growth factors such as VEGF.26
METHODS
SUBJECTS AND TREATMENTS
We retrospectively reviewed 29 eyes of 29 consecutive patients with AMD who had been treated with full macular translocation surgery with CNV membrane removal at 10 distinct surgical sites between 1997 and 2005. Except for 14 patients without any preoperative therapy (control CNV group), surgery was performed 3 to 9 days after verteporfin PDT (PDT CNV group; n = 4), TA monotherapy (TA CNV group; n = 5), or PDT+TA combination therapy (PDT+TA CNV group; n = 6). The clinical characteristics of patients treated with PDT, TA, or PDT+TA preoperatively are summarized in the Table.
|
|
|
|
Table. Clinical Characteristics of Patients Treated With Intravitreal TA and/or Verteporfin PDT Before Surgical Removal of Subfoveal CNV Membrane
|
|
|
Full macular translocation was offered when (1) visual acuity was worse than 20/200, being the minimum visual acuity to recommend the first PDT treatment,2 (2) visual deterioration progressed after initial PDT, (3) the patient refused (re)treatment with PDT, TA, or PDT+TA owing to continuous visual deterioration in the fellow eye in spite of therapy, and (4) (re)treatment with PDT was impossible owing to recurrent or massive submacular hemorrhage. Preoperative therapy with PDT, TA, and PDT+TA was intended to decrease intraoperative hemorrhage, postoperative CNV recurrence, and the proliferative vitreoretinopathy rate.5-7,27 Triamcinolone acetonide was prepared preservative-free through a sedimentation technique previously described.28-29 Each patient gave written informed consent after the experimental nature, risks, and benefits of all of the therapy options had been explained. The study followed the guidelines of the Declaration of Helsinki. The study and histological analysis of specimens were approved by the local institutional review board.
IMMUNOHISTOLOGY
The CNV specimens were fixed in formalin and embedded in paraffin. Each specimen was sectioned into 5-µm sections and mounted on poly-L-lysine–coated glass slides (Dako, Glostrup, Denmark) for immunohistochemical staining. After deparaffinization, antigen retrieval was performed through heat treatment in citrate buffer (0.01M; pH, 6.0) for 2 minutes for CD34, ICAM-1, E-selectin, CD45, CD68, and Ki-67. For cytokeratin 18 and Thy-1, antigen retrieval was accomplished by proteolytic digestion with 0.5% protease XXIV (Sigma, St Louis, Missouri) for 10 minutes, whereas pretreatment with proteinase K (Dako) for 10 minutes was used for VEGF. Owing to inadequate pretreatment stability of 2 sections, only 2 PDT CNV were stained for E-selectin, ICAM-1, CD68, and CD45.
Immunohistochemical staining with the primary mouse monoclonal antibodies specific for CD34 (Clone QBEnd-10; Immunotech, Hamburg, Germany), cytokeratin 18 (Clone:Ks 18.04; Progen, Heidelberg, Germany), ICAM-1 (Clone 23G12; Novocastra, Newcastle upon Tyne, England), E-selectin (Clone 16G4; Novocastra), CD45 (Clones 2B11 and PD7/26; Dako), and Ki-67 (Clone MIB-1; Dako) was performed using a horse radish peroxidase method previously described.26 For E-selectin, cytokeratin 18, and ICAM-1 staining, the brown chromogen 3,3'-diaminobenzidine was replaced with 3-amino-9-ethylcarbazole, a highly sensitive substrate chromogen (Cytomation, Code K3461; Dako).
Immunohistochemical staining with the primary mouse antibodies specific for VEGF (sc-7269; Santa Cruz Biotechnology Inc, Santa Cruz, California), Thy-1 (clone 5E10; BD Biosciences, Pharmingen, San Jose, California), and CD68 (Clone PG-M1; Dako) was performed by an alkaline-phosphatase method previously described.30 Color was developed using chromogen red (ChemMate Detection Kit; Dako). Hematoxylin (ChemMate, Code S2020; Dako) was used for counterstaining. For negative controls, primary antibodies were substituted with either the appropriate or normal sera.
STATISTICAL ANALYSIS
Two serial sections were analyzed for each specimen independently by 2 masked observers (O.T. and S.G.) by light microscopy.
Immunoreactivity for VEGF, ICAM-1, and E-selectin was analyzed separately in the RPE, EC, and stroma by light microscopy. Numerals 3, 2, 1, and 0 were assigned to indicate intense (70%-100% positive cells), moderate (40%-69% positive cells), or weak labeling (1%-39% positive cells), or and absence of any staining, respectively. The total score for VEGF, ICAM-1, and E-selectin (range, 0-9) was described for each CNV specimen by the sum of the staining scores in the RPE, EC, and stroma.
Thy-1 expression was determined by the percentage of Thy-1–expressing vessels in the overall vascularization detected by the number of CD34+ vascular-like patterns in each membrane.
All Ki-67–positive nuclei, CD45+ leukocytes, and CD68+ macrophages were counted in each specimen. The area of each specimen was measured using appropriate software (AxioVision version 3.1; Carl Zeiss, Göttingen, Germany). The density of leukocytes and macrophages and the proliferative activity were determined separately for each CNV membrane by the ratio of the total number of leukocytes, macrophages, and Ki-67–positive nuclei to the total area of membrane (in millimeters squared), respectively.
Analyses of variance (ANOVA) followed by Fisher protected least significant difference (PLSD) post hoc testing was used for statistical analysis. P < .05 was considered significant.
RESULTS
Immunohistopathological findings are summarized in the Figure.
|
|
|
|
Figure. Graphs showing intercellular adhesion molecule (ICAM)–1 (A) and E-selectin (B) immunostaining intensity, proliferative activity, density of leukocytes and macrophages (C), percentage of Thy-1–immunopositive vessels (D), and vascular endothelial growth factor (VEGF) immunoreactivity intensity (E) in choroidal neovascularization (CNV) membranes without previous therapy (Control CNV) and those excised after verteporfin photodynamic therapy (PDT CNV), triamcinolone acetonide monotherapy (TA CNV), and PDT+TA combination therapy (PDT+TA CNV). Immunostaining of ICAM-1, E-selectin, and VEGF in the retinal pigment epithelium (RPE), endothelial cells (EC), and stroma were evaluated separately and semiquantitatively as intense (70%-100% positive cells), moderate (40%-69% positive cells), weak (1%-39% positive cells), or absent (A, B, E). All Ki-67–positive nuclei, CD45-immunoreactive leukocytes, and CD68-immunopositive macrophages were counted in each specimen. Proliferative activity and density of leukocytes and macrophages were determined separately for each CNV membrane by the ratio of the total number of proliferating cells, leukocytes, and macrophages to the total area of the membrane, respectively; their mean values with standard errors are shown in (C). The percentage of Thy-1 expressing vessels in the overall vascularization was calculated for each membrane (D).
|
|
|
EXPRESSION OF CELLULAR ADHESION MOLECULES ICAM-1 AND E-SELECTIN
Immunoreactivity to ICAM-1 was detected in the RPE, EC, and stroma of 92.86% (13 of 14), 35.72% (5 of 14), and 71.43% (10 of 14) of control CNV membranes, respectively (Figure, A and eFigure 1 A). Expression of ICAM-1 in the EC (ANOVA P < .001) and stroma (ANOVA P < .001) as well as the total ICAM-1 score (ANOVA P < .001) showed significant differences between subgroups.
Immunoreactivity to ICAM-1 was intense in the RPE of both PDT CNV membranes and was weak in the stroma of 1 PDT CNV membrane (Figure, A and eFigure 1 B).
In all TA CNV membranes (n = 5), RPE, EC, and stromal cells displayed ICAM-1 intensely. It was also significantly stronger in the EC, stroma, and in the total score than in the control CNV membranes (P < .001 for all) and PDT CNV membranes (P = .004, P < .001, and P = .001, respectively) (Figure, A and eFigure 1 C).
Intense ICAM-1 expression was detected in the RPE of all, the EC of 4 (66.67%), and the stroma of 5 (83.3%) PDT+TA CNV membranes (n = 6) (Figure, A and eFigure 1 D). Also, ICAM-1 expression was significantly stronger in the EC, stroma, and total score than in both of the control CNV (P = .004, P < .001, and P < .001, respectively) and PDT CNV membranes (P = .01, P = 004, and P = .002, respectively). No significant change was detected in ICAM-1 expression between the TA and PDT+TA CNV membranes.
The control CNV membranes showed E-selectin immunoreactivity in the RPE of all, the EC of 8 (57.14%), and the stroma of 9 (64.29%) specimens (Figure, B). In the PDT CNV membranes, E-selectin was present in the RPE and EC of 1 CNV membrane (Figure, B). The TA CNV membranes showed E-selectin immunoreactivity in the RPE of 2 (40%) and the EC and stroma of 1 CNV membrane (20%) (Figure, B and eFigure 1, E). Immunoreactivity to E-selectin was detected in the RPE of 4 (66.67%), the EC of 3 (50.00%), and the stroma of 1 PDT+TA CNV membrane (16.67%) (Figure, B and eFigure 1 F). No significant difference in E-selectin expression was found between any of subgroups.
LEUKOCYTE AND MACROPHAGE DENSITY AND PROLIFERATIVE ACTIVITY IN CNV MEMBRANES
The mean (SE) density of macrophages in the control, PDT, and TA CNV membranes were 1028.33 (224.64), 235.95 (185.63), and 1433.26 (399.94) cells/mm3, respectively (Figure, C). The mean (SE) macrophage density in the PDT+TA CNV membranes (2831.31 [481.29] cells/mm3) was significantly higher than in the control (P < .001), PDT (P = .002), and TA CNV membranes (P = .02) (ANOVA P = .002) (eFigure 2 A-D). The higher macrophage density in the TA than in the control and PDT CNV membranes did not show significance (P = .41).
Leukocytes were present in all but 1 control CNV membrane, with a mean (SE) density of 180.92 (52.34) cells/mm3. The density of leukocytes in 2 PDT CNV membranes ranged from 0 to 3.73 cells/mm3 (Figure, C). In the TA CNV membranes, the mean (SE) density of leukocytes tended to decrease to 56.67 (17.69) cells/mm3 (Figure, C and eFigure 3 E). Leukocytes were found in 5 of 6 PDT+TA CNV membranes, with a mean (SE) density of 131.13 (41.57) cells/mm3(Figure, C and eFigure 3 F). No significant difference was found between any groups (ANOVA P = .35)
The mean (SE) proliferative activity was 96.57 (37.48) cells/mm3 in the control and 22.18 (19.02) cells/mm3 in the PDT CNV membranes (Figure, C). The mean (SE) proliferative activity in the TA (38.91 [21.29] cells/mm3) (Figure, C and eFigure 2 G) and PDT+TA CNV membranes (18.19 [4.96] cells/mm3) (Figure 1 C and eFigure 3 H) was smaller than in the control CNV membranes, but without significance (ANOVA P = .35).
ANGIOGRAPHIC FINDINGS, CD34, AND THY-1 IMMUNOREACTIVITY
Following PDT and PDT+TA therapy, a hypofluorescence suggesting nonperfusion of the irradiated area and CNV membrane was detected in fluorescein angiography on the day of surgery (eFigure 2 A). In addition, CD34 immunohistochemistry demonstrated mostly occluded vessels with damaged EC (eFigure 2 B). In contrast, the control CNV membranes showed patent vessels lined with healthy EC.
All CNV membranes were vascularized. Thy-1 immunoreactivity was detected in all but 1 control CNV membrane, with a mean (SD) percentage of 73.93% (8.76%) of vessels (Figure, D and eFigure 3 C). In the PDT CNV membranes, 10% of vessels of only 1 CNV membrane displayed Thy-1 immunoreactivity, whereas other CNV membranes were immunonegative (Figure, D and eFigure 3 D). All vessels in all TA CNV membranes were stained for Thy-1 (Figure, D and eFigure 3 E). The mean percentage of Thy-1 expressing vessels was 98.33% (1.67%) in the PDT+TA CNV membranes (Figure 1 D and eFigure 3 F). The percentage of Thy-1–expressing vessels showed a significant difference between subgroups (ANOVA P < .001), being significantly higher in the TA and PDT+TA CNV membranes than in both the control (P = .04 and P = .04, respectively) and PDT CNV membranes (P < .001 for both). The percentage of Thy-1–expressing vessels in the TA and PDT+TA CNV membranes was comparable with each other (P = .9).
IMMUNOREACTIVITY OF VEGF IN CNV MEMBRANES
Immunoreactivity to VEGF was detected in the RPE, EC, and stroma of 10 (71.43%), 8 (57.14%), and 13 (92.86%) control CNV membranes, respectively. Intense VEGF expression was found in the RPE of 4 (28.57%) CNV membranes (Figure, E and eFigure 4 A). The PDT CNV group displayed VEGF in the RPE intensely in all CNV membranes, and either weakly or moderately in the EC of 3 and the stroma of all specimens (Figure, E and eFigure 5 B). The RPE, EC, and stroma displayed VEGF in all TA CNV membranes and intensely in 3 (60%) (Figure, E and eFigure 4 C). The PDT+TA CNV membranes displayed VEGF intensely in the RPE and stromal cells of 5 (83.33%) CNV membranes and in the EC of 3 (50%) (Figure, E and eFigure 4 D). Expression of VEGF was significantly more intense in the RPE of the PDT+TA than the control CNV membranes (ANOVA P = .05, P = .02). The total VEGF scores in the TA (P = .05) and PDT+TA (P = .01) CNV were also higher than in the control CNV group (ANOVA P = .05). Expression of VEGF in the TA and PDT+TA CNV group did not show any significant changes with respect to each other or the PDT CNV specimens.
COMMENT
Knowledge about inflammation in the pathogenesis of neovascular AMD is increasing. Inflammatory constituents of drusen induce VEGF expression.31 In turn, VEGF stimulates expression of ICAM-1 and E-selectin on vascular EC and facilitates migration of inflammatory cells to neovascularization.32-37 There is a closed but amplifying circuit between VEGF and inflammatory cells because leukocytes produce VEGF and stimulate RPE and fibroblasts to produce VEGF.36-40 Enhanced VEGF expression in the RPE induces CNV.41 New neovascular AMD treatment strategies therefore target the complement system, ICAM-1, and macrophages.39-40,42 They inhibit leukocyte infiltration and VEGF expression and therefore CNV development.39-40 Triamcinolone acetonide inhibits experimental CNV10-12 and was suggested to alter inflammatory cell activity and/or numbers,10, 12 reduce VEGF expression,16-21 or downregulate ICAM expression.13-14 It is efficacious in AMD treatment.3-4 Herein, we evaluated the early effects of TA on cellular adhesion molecules, inflammatory cell infiltration and activity, Thy-1, and proliferation in human CNV.
In our series, control CNV were mostly inflammatory active, with varying densities of leukocytes, macrophages, Thy-1, ICAM-1, and E-selectin expression. Leukocytes and macrophages were previously found to be present in CNV membranes.43-46 In concordance with Yeh et al,47 we found ICAM-1 expression mainly and intensely in the RPE. E-selectin was present in the EC, stroma, and RPE, as previously reported.47-49 Intense VEGF expression was detected in the RPE, EC, and stroma in less than 30% of the specimens.
In TA or PDT+TA CNV membranes, the density of CD45 immunopositive peripheral leukocytes tended to decrease in comparison with control CNV membranes, similar to observations of Ciulla et al.11 Surprisingly, the density of CD68 immunoreactive resident macrophages was higher in both the TA or PDT+TA CNV membranes than in the controls, but significantly increased only in the PDT+TA CNV membranes. Macrophages synthesize IL-1 and TNF-.36, 45, 50-51 Hence, increased macrophage density was associated with significantly higher Thy-1 expression, reflecting enhanced IL-1 and TNF- activity. Both IL-1 and TNF- further enhance ICAM-1 expression in EC and the RPE.52-54 Additionally, macrophages induce VEGF production in the RPE through IL-1 and TNF-.38 The density of infiltrating inflammatory cells is correlated with VEGF levels in CNV.39-40,50, 55 Increased density of macrophage infiltration and Thy-1 expression, therefore, is associated with an increased total VEGF expression score in TA and PDT+TA CNV.42 Enhanced VEGF expression might restimulate the cascade by enhancing ICAM-1 expression and macrophage infiltration.32-37
The effect of TA on inflammation has been previously studied. Ishibashi et al10 supposed that TA might inhibit experimental CNV through inhibiting infiltration of inflammatory cells, especially of macrophages. Penfold et al15 suggested that TA diminished numbers of dendritiform microglia but not macrophage-like populations in neural retina overlying subretinal proliferation. Monotherapy with TA reduced permeability and expression of ICAM-1 in choroidal EC.13-14 However, E-selectin was unaffected.14 Macrophage infiltration was increased after subconjunctival injection of TA.56 Antoszky et al8 suggested that the angiostatic, but not anti-inflammatory, effect of TA was significant in preventing neovascularization.
Age, maturity, pretreatment inflammatory activity, and VEGF expression in CNV cannot be predicted. In contrast, the time of PDT application acts as an artificial time zero. Photodynamic therapy induces a significant decrease in inflammatory cell infiltration and activity46 and a significant increase in VEGF expression by the RPE.25, 49 Therefore, PDT CNV serves as an ideal control group for PDT+TA CNV. Their comparison also revealed increased macrophage infiltration, enhanced Thy-1 and ICAM-1 expression, and increased VEGF total score in the PDT+TA CNV group as well as persisting intense VEGF expression in the RPE. Enhanced VEGF in ARPE-19 by cellular uptake of verteporfin was suppressed by TA in vitro.20 However, TA reduced VEGF expression in the RPE induced by either oxidative stress18 or IL-1, but did not affect hypoxia-stimulated VEGF expression.21 It is still unknown which is causative for increased VEGF expression after PDT. Furthermore, responses in vivo are different and influenced by cell types, vascularization, and perfusion. In addition, TA reduces VEGF in the ARPE-19 cell line, vascular smooth cells, EC, and Muller cells in vitro,17-19,21 but not in rat retina and hemangioma in vivo.57-58
This study shows that TA and PDT+TA CNV membranes are inflammatory active, showing many macrophages. However, macrophages are not only proangiogenic. First, macrophages control vessel growth and are required for cell death and tissue remodeling in the eye.59-60 During vascular regression, macrophages regulate EC apoptosis. In the case of macrophage elimination, EC survive and capillaries persist.59-62 Similarly, in our specimens, macrophages might be recruited to remove the cellular debris early after the treatment. Second, macrophages inhibit angiogenesis through the release of proteolytic enzymes36 that activate endogenous angiogenesis inhibitors such as endostatin. Correspondingly, endostatin was enhanced in TA and PDT+TA CNV.23 Third, macrophages are involved in CNV inhibition. Mice deficient in monocyte chemotactic protein–1 develop CNV.31 Inhibition of macrophage entry into the eye promotes CNV, whereas direct injection of macrophages inhibits CNV.63 Previously, macrophage depletion with liposomes was shown to inhibit CNV.39-40 However, reduction of neovascularization was recently suggested to be due to direct toxicity of liposomes on EC.63
Proliferative activity is significantly higher in inflammatory active CNV.30, 46, 48 The TA and PDT+TA CNV membranes were highly infiltrated with macrophages; however, mean proliferative activity was lower than in the control CNV membranes, possibly owing to the antiproliferative effect of TA.64
We are unaware of previous reports of clinicopathological evaluation of ICAM-1, inflammation, and proliferation in human CNV treated with TA or PDT+TA combination therapy. Proper interpretation of the study is limited by the small number of specimens and the possibility of selection bias. An absolute quantification of mRNA and/or protein expression by real time polymerase chain reaction and/or Western blot in further studies will surely supply additional valuable information. Nevertheless, TA and PDT+TA CNV membranes show infiltration with a significantly higher density of resident macrophages and intense VEGF expression early after therapy, although its duration is unknown. Proliferative activity and density of leukocytes tend to be lower in TA and PDT+TA CNV membranes. In contrast, CNV membranes treated with bevacizumab, a full-length recombinant humanized monoclonal antibody against VEGF, show higher proliferative activity and leukocyte density than control CNV membranes.65 Whether these are sufficient rationales for triple combination therapy including PDT, TA, and anti-VEGF agents, as recently introduced, needs to be further evaluated.66
AUTHOR INFORMATION
Correspondence: Salvatore Grisanti, MD, Department of Ophthalmology at the University of Luebeck, Ratzeburger Allee 160, 23538 Luebeck, Germany (salvatore.grisanti{at}uk-sh.de).
Submitted for Publication: January 17, 2008; final revision received September 21, 2008; accepted September 24, 2008.
Financial Disclosure: None reported.
Funding/Support: This study was supported by the Vision 100 Foundation and the Jung Foundation.
Author Contributions: Drs Tatar and Grisanti had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Author Affiliations: University Eye Hospital at the Centre for Ophthalmology of the Eberhard-Karls University, Tuebingen, Germany (Drs Tatar, Yoeruek, Szurman, and Bartz-Schmidt); Department of Pathology, University of Tuebingen, Tuebingen, Germany (Dr Kaiserling and Ms Adam); Laboratory of Visual Physiology, National Institute of Sensory Organs, Tokyo, Japan (Dr Shinoda); AZ-Sint Augustinus, Antwerp, Belgium (Drs Boeyden and Claes); Augenklinik der Staedtischen Kliniken, Frankfurt am Main, Germany (Drs Eckert and Eckardt); Department of Ophthalmology, Sacro Cuore Hospital, Negrar, Italy (Dr Pertile); Augenzentrum Recklinghausen, Recklinghausen, Germany (Dr Scharioth); and Department of Ophthalmology, University Eye Hospital Luebeck, Luebeck, Germany (Dr Grisanti).
REFERENCES
1. Congdon N, O'Colmain B, Klaver CC; et al, Eye Diseases Prevalence Research Group. Causes and prevalence of visual impairment among adults in the United States. Arch Ophthalmol. 2004;122(4):477-485.
FREE FULL TEXT
2. Bressler NM, Treatment of Age-Related Macular Degeneration With Photodynamic Therapy (TAP) Study Group. Photodynamic therapy of subfoveal choroidal neovascularization in age-related macular degeneration with verteporfin: two-year results of 2 randomized clinical trials: TAP report 2. Arch Ophthalmol. 2001;119(2):198-207.
FREE FULL TEXT
3. Gillies MC, Simpson JM, Luo W; et al. A randomized clinical trial of a single dose of intravitreal triamcinolone acetonide for neovascular age-related macular degeneration: one-year results. Arch Ophthalmol. 2003;121(5):667-673.
FREE FULL TEXT
4. Spaide RF, Sorenson J, Maranan L. Photodynamic therapy with verteporfin combined with intravitreal injection of triamcinolone acetonide for choroidal neovascularization. Ophthalmology. 2005;112(2):301-304.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
5. Hui YN, Liang HC, Cai YS, Kirchhof B, Heimann K. Corticosteroids and daunomycin in the prevention of experimental proliferative vitreoretinopathy induced by macrophages. Graefes Arch Clin Exp Ophthalmol. 1993;231(2):109-114.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
6. Chandler DB, Rozakis G, de Juan EJ Jr, Machemer R. The effect of triamcinolone acetonide on a refined experimental model of proliferative vitreoretinopathy. Am J Ophthalmol. 1985;99(6):686-690.
WEB OF SCIENCE
| PUBMED
7. Tano Y, Chandler D, Machemer R. Treatment of intraocular proliferation with intravitreal injection of triamcinolone acetonide. Am J Ophthalmol. 1980;90(6):810-816.
WEB OF SCIENCE
| PUBMED
8. Antoszyk AN, Gottlieb JL, Machemer R, Hatchell DL. The effects of intravitreal triamcinolone acetonide on experimental pre-retinal neovascularization. Graefes Arch Clin Exp Ophthalmol. 1993;231(1):34-40.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
9. Danis RP, Bingaman DP, Yang Y, Ladd B. Inhibition of preretinal and optic nerve head neovascularization in pigs by intravitreal triamcinolone acetonide. Ophthalmology. 1996;103(12):2099-2104.
WEB OF SCIENCE
| PUBMED
10. Ishibashi T, Miki K, Sorgente N, Patterson R, Ryan SJ. Effects of intravitreal administration of steroids on experimental subretinal neovascularization in the subhuman primate. Arch Ophthalmol. 1985;103(5):708-711.
FREE FULL TEXT
11. Ciulla TA, Criswell MH, Danis RP, Hill TE. Intravitreal triamcinolone acetonide inhibits choroidal neovascularization in a laser-treated rat model. Arch Ophthalmol. 2001;119(3):399-404.
FREE FULL TEXT
12. Ciulla TA, Criswell MH, Danis RP; et al. Choroidal neovascular membrane inhibition in a laser treated rat model with intraocular sustained release triamcinolone acetonide microimplants. Br J Ophthalmol. 2003;87(8):1032-1037.
FREE FULL TEXT
13. Penfold PL, Wen L, Madigan MC, Gillies MC, King NJ, Provis JM. Triamcinolone acetonide modulates permeability and intercellular adhesion molecule-1 (ICAM-1) expression of the ECV304 cell line: implications for macular degeneration. Clin Exp Immunol. 2000;121(3):458-465.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
14. Penfold PL, Wen L, Madigan MC, King NJ, Provis JM. Modulation of permeability and adhesion molecule expression by human choroidal endothelial cells. Invest Ophthalmol Vis Sci. 2002;43(9):3125-3130.
FREE FULL TEXT
15. Penfold PL, Wong JG, Gyory J, Billson FA. Effects of triamcinolone acetonide on microglial morphology and quantitative expression of MHC-II in exudative AMD. Clin Exp Ophthalmol. 2001;29:188-192.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
16. Brooks HL Jr, Caballero S Jr, Newell CK; et al. Vitreous levels of vascular endothelial growth factor and stromal-derived factor 1 in patients with diabetic retinopathy and cystoid macular edema before and after intraocular injection of triamcinolone. Arch Ophthalmol. 2004;122(12):1801-1807.
FREE FULL TEXT
17. Nauck M, Karakiulakis G, Perruchoud AP, Papakonstantinou E, Roth M. Corticosteroids inhibit the expression of the vascular endothelial growth factor gene in human vascular smooth muscle cells. Eur J Pharmacol. 1998;341(2-3):309-315.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
18. Matsuda S, Gomi F, Oshima Y, Tohyama M, Tano Y. Vascular endothelial growth factor reduced and connective tissue growth factor induced by triamcinolone in ARPE19 cells under oxidative stress. Invest Ophthalmol Vis Sci. 2005;46(3):1062-1068.
FREE FULL TEXT
19. Tong JP, Lam DS, Chan WM, Choy KW, Chan KP, Pang CP. Effects of triamcinolone on the expression of VEGF and PEDF in human retinal pigment epithelial and human umbilical vein endothelial cells. Mol Vis. 2006;12:1490-1495.
WEB OF SCIENCE
| PUBMED
20. Obata R, Inoue Y, Iriyama A, Takahashi H, Tamaki Y, Yanagi Y. Triamcinolone acetonide suppresses early proangiogenic response in retinal pigment epithelial cells after photodynamic therapy in vitro [published online ahead of print September 20, 2006]. Br J Ophthalmol. 2007;91(1):100-104.
FREE FULL TEXT
21. Itakura H , Akiyama H, Hagimura N; et al. Triamcinolone acetonide suppresses interleukin-1 beta-mediated increase in vascular endothelial growth factor expression in cultured rat Muller cells [published online ahead of print July 28, 2005]. Graefes Arch Clin Exp Ophthalmol. 2006;244(2):226-231.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
22. Kwak N, Okamoto N, Wood J, Campochiaro P. VEGF is major stimulator in model of choroidal neovascularization. Invest Ophthalmol Vis Sci. 2000;41(10):3158-3164.
FREE FULL TEXT
23. Tatar O, Shinoda K, Kaiserling E; et al. Early effects of triamcinolone on vascular endothelial growth factor and endostatin in human choroidal neovascularization. Arch Ophthalmol. 2008;126(2):193-199.
FREE FULL TEXT
24. Carson MJ, Reilly CR, Sutcliffe JG, Lo D. Mature microglia resemble immature antigen-presenting cells. Glia. 1998;22(1):72-85.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
25. Denker SP, Ji S, Dingman A; et al. Macrophages are comprised of resident brain microglia not infiltrating peripheral monocytes acutely after neonatal stroke [published online ahead of print December 22, 2006]. J Neurochem. 2007;100(4):893-904.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
26. Lee WS, Jain MK, Arkonac BM; et al. Thy-1, a novel marker for angiogenesis upregulated by inflammatory cytokines. Circ Res. 1998;82(8):845-851.
FREE FULL TEXT
27. Martidis A, Miller DG, Ciulla TA, Danis RP, Moorthy RS. Corticosteroids as an antiangiogenic agent for histoplasmosis-related subfoveal choroidal neovascularization. J Ocul Pharmacol Ther. 1999;15(5):425-428.
WEB OF SCIENCE
| PUBMED
28. Szurman P, Kaczmarek R, Jaissle GB; et al. Influence of different purification techniques on triamcinolone yield and particle size spectrum [published online ahead of print September 28, 2006]. Graefes Arch Clin Exp Ophthalmol. 2007;245(5):689-696.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
29. Bitter C, Suter K, Figueiredo V, Pruente C, Hatz K, Surber C. Preservative-free triamcinolone acetonide suspension developed for intravitreal injection. J Ocul Pharmacol Ther. 2008;24(1):62-69.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
30. Tatar O, Kaiserling E, Adam A; et al. Consequences of verteporfin photodynamic therapy on choroidal neovascular membranes. Arch Ophthalmol. 2006;124(6):815-823.
FREE FULL TEXT
31. Ambati J, Anand A, Fernandez S; et al. An animal model of age-related macular degeneration in senescent Ccl-2- or Ccr-2-deficient mice [published online ahead of print October 19, 2003]. Nat Med. 2003;9(11):1390-1397.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
32. Kim I, Moon SO, Kim SH, Kim HJ, Koh YS, Koh GY. Vascular endothelial growth factor expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin through nuclear factor-kappa B activation in endothelial cells [published online ahead of print December 6, 2000]. J Biol Chem. 2001;276(10):7614-7620.
FREE FULL TEXT
33. Joussen AM, Poulaki V, Qin W; et al. Retinal vascular endothelial growth factor induces intercellular adhesion molecule-1 and endothelial nitric oxide synthase expression and initiates early diabetic retinal leukocytes adhesion in vivo. Am J Pathol. 2002;160(2):501-509.
WEB OF SCIENCE
| PUBMED
34. Clauss M, Gerlach M, Gerlach H; et al. Vascular permeability factor: a tumor-derived polypeptide that induces endothelial cell and monocyte procoagulant activity, and promotes monocyte migration. J Exp Med. 1990;172(6):1535-1545.
FREE FULL TEXT
35. Barleon B, Sozzani S, Zhou D, Weich HA, Mantovani A, Marme D. Migration of human monocytes in response to vascular endothelial growth factor (VEGF) is mediated via the VEGF receptor flt-1. Blood. 1996;87(8):3336-3343.
FREE FULL TEXT
36. Sunderkötter C, Steinbrink K, Goebeler M, Bhardwaj R, Sorg C. Macrophages and angiogenesis. J Leukoc Biol. 1994;55(3):410-422.
ABSTRACT
37. Ferrara N. Vascular endothelial growth factor: basic science and clinical progress. Endocr Rev. 2004;25(4):581-611.
FREE FULL TEXT
38. Oh H, Takagi H, Takagi C; et al. The potential angiogenic role of macrophages in the formation of choroidal neovascular membranes. Invest Ophthalmol Vis Sci. 1999;40(9):1891-1898.
FREE FULL TEXT
39. Sakurai E, Anand A, Ambati BK, van Rooijen N, Ambati J. Macrophage depletion inhibits experimental choroidal neovascularization. Invest Ophthalmol Vis Sci. 2003;44(8):3578-3585.
FREE FULL TEXT
40. Espinosa-Heidmann DG, Suner IJ, Hernandez EP, Monroy D, Csaky KG, Cousins SW. Macrophage depletion diminishes lesion size and severity in experimental choroidal neovascularization. Invest Ophthalmol Vis Sci. 2003;44(8):3586-3592.
FREE FULL TEXT
41. Spilsbury K, Garrett KL, Shen WY, Constable IJ, Rakoczy PE. Overexpression of vascular endothelial growth factor (VEGF) in the retinal pigment epithelium leads to the development of choroidal neovascularization [correction published in Am J Pathol. 2000;157(4):1413]. Am J Pathol. 2000;157(1):135-144.
WEB OF SCIENCE
| PUBMED
42. Sakurai E, Taguchi H, Anand A; et al. Targeted disruption of the CD18 or ICAM-1 gene inhibits choroidal neovascularization. Invest Ophthalmol Vis Sci. 2003;44(6):2743-2749.
FREE FULL TEXT
43. Grossniklaus HE, Ling JX, Wallace TM; et al. Macrophage and retinal pigment epithelium expression of angiogenic cytokines in choroidal neovascularization. Mol Vis. 2002;8:119-126.
WEB OF SCIENCE
| PUBMED
44. Grossniklaus HE, Martinez JA, Brown VB; et al. Immunohistochemical and histochemical properties of surgically excised subretinal neovascular membranes in age-related macular degeneration. Am J Ophthalmol. 1992;114(4):464-472.
WEB OF SCIENCE
| PUBMED
45. Seregard S, Algvere PV, Berglin L. Immunohistochemical characterization of surgically removed subfoveal fibrovascular membranes. Graefes Arch Clin Exp Ophthalmol. 1994;232(6):325-329.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
46. Tatar O, Adam A, Shinoda K; et al. Influence of verteporfin photodynamic therapy on inflammation in human choroidal neovascular membranes secondary to age-related macular degeneration. Retina. 2007;27(6):713-723.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
47. Yeh DC, Bula DV, Miller JW, Gragoudas ES, Arroyo JG. Expression of leukocyte adhesion molecules in human subfoveal choroidal neovascular membranes treated with and without photodynamic therapy. Invest Ophthalmol Vis Sci. 2004;45(7):2368-2373.
FREE FULL TEXT
48. Tatar O, Shinoda K, Adam A; et al. Expression of endostatin in human choroidal neovascular membranes secondary to age-related macular degeneration [published online ahead of print April 11, 2006]. Exp Eye Res. 2006;83(2):329-338.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
49. Tatar O, Shinoda K, Adam A; et al. Effect of verteporfin photodynamic therapy on endostatin and angiogenesis in human choroidal neovascular membranes [published online ahead of print September 20, 2006]. Br J Ophthalmol. 2007;91(2):166-173.
FREE FULL TEXT
50. Nishimura T, Goodnight R, Prendergast RA, Ryan SJ. Activated macrophages in experimental subretinal neovascularization. Ophthalmologica. 1990;200(1):39-44.
WEB OF SCIENCE
| PUBMED
51. Leibovich SJ, Polverini PJ, Shepard HM, Wiseman DM, Shively V, Nuseir N. Macrophage-induced angiogenesis is mediated by tumour necrosis factor-alpha. Nature. 1987;329(6140):630-632.
FULL TEXT
| PUBMED
52. Pavilack MA, Elner VM, Elner SG, Todd RF III, Huber AR. Differential expression of human corneal and perilimbal ICAM-1 by inflammatory cytokines. Invest Ophthalmol Vis Sci. 1992;33(3):564-573.
FREE FULL TEXT
53. Elner SG, Elner VM, Pavilack MA; et al. Modulation and function of intercellular adhesion molecule-1 (CD54) on human retinal pigment epithelial cells. Lab Invest. 1992;66(2):200-211.
WEB OF SCIENCE
| PUBMED
54. Platts KE, Benson MT, Rennie IG, Sharrard RM, Rees RC. Cytokine modulation of adhesion molecule expression on human retinal pigment epithelial cells. Invest Ophthalmol Vis Sci. 1995;36(11):2262-2269.
FREE FULL TEXT
55. Tsutsumi C, Sonoda KH, Egashira K; et al. The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization. J Leukoc Biol. 2003;74(1):25-32.
FREE FULL TEXT
56. Giangiacomo J, Dueker DK, Adelstein EH. Histopathology of triamcinolone in the subconjunctiva. Ophthalmology. 1987;94(2):149-153.
WEB OF SCIENCE
| PUBMED
57. Gao H, Qiao X, Gao R, Mieler WF, McPherson AR, Holz ER. Intravitreal triamcinolone does not alter basal vascular endothelial growth factor mRNA expression in rat retina. Vision Res. 2004;44(4):349-356.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
58. Hasan Q, Tan ST, Gush J, Peters SG, Davis PF. Steroid therapy of a proliferating hemangioma: histochemical and molecular changes. Pediatrics. 2000;105(1, pt 1):117-120.
FREE FULL TEXT
59. Lobov IB, Rao S, Carroll TJ; et al. WNT7b mediates macrophage-induced programmed cell death in patterning of the vasculature. Nature. 2005;437(7057):417-421.
FULL TEXT
| PUBMED
60. Lang RA. Apoptosis in mammalian eye development: lens morphogenesis, vascular regression and immune privilege. Cell Death Differ. 1997;4(1):12-20.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
61. Diez-Roux G, Argilla M, Makarenkova H, Ko K, Lang RA. Macrophages kill capillary cells in G1 phase of the cell cycle during programmed vascular regression. Development. 1999;126(10):2141-2147.
ABSTRACT
62. Diez-Roux G, Lang RA. Macrophages induce apoptosis in normal cells in vivo. Development. 1997;124(18):3633-3638.
ABSTRACT
63. Apte RS, Richter J, Herndon J, Ferguson TA. Macrophages inhibit neovascularization in a murine model of age-related macular degeneration. PLoS Med. 2006;3(8):e310.
FULL TEXT
| PUBMED
64. Spandau UH, Sauder G, Schubert U, Hammes HP, Jonas JB. Effect of triamcinolone acetonide on proliferation of retinal endothelial cells in vitro and in vivo. Br J Ophthalmol. 2005;89(6):745-747.
FREE FULL TEXT
65. Tatar O, Adam A, Shinoda K; et al. Effect of bevacizumab on inflammation and proliferation in human choroidal neovascularization. Arch Ophthalmol. 2008;126(6):782-790.
FREE FULL TEXT
66. Liggett PE, Colina J, Chaudhry NA, Tom D, Haffner G. Triple therapy of intravitreal triamcinolone, photodynamic therapy, and pegaptanib sodium for choroidal neovascularization [published online ahead of print September 1, 2006]. Am J Ophthalmol. 2006;142(6):1072-1074.
FULL TEXT
|
WEB OF SCIENCE
| PUBMED
 CiteULike  Connotea  Delicious  Digg  Facebook  Reddit  Technorati  Twitter
What's this?
|
