Expression of autotaxin and acylglycerol kinase in proliferative vitreoretinal epiretinal membranes.

PURPOSE: Lysophosphatidic acid (LPA)/LPA(1) receptor pathway is involved in inflammation, angiogenesis and fibrosis. This study was conducted to analyse the expression of LPA-producing enzymes, autotaxin (ATX) and acylglycerol kinase (AGK) and LPA(1) receptor, in proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR) epiretinal membranes. METHODS: Nine active and 13 inactive membranes from patients with PDR and 21 membranes from patients with PVR were studied by immunohistochemistry. RESULTS: In PDR membranes, vascular endothelial cells expressed ATX and AGK in 16 and 19 membranes, respectively. Stromal cells expressed ATX and AGK in 19 and 22 membranes, respectively. Immunoreactivity for LPA(1) receptor was noted in vascular endothelial cells and stromal cells in the five membranes stained for LPA(1) receptor. Numbers of blood vessels and stromal cells expressing CD34, ATX and AGK were significantly higher in active membranes than in inactive membranes. Significant correlations were detected between number of blood vessels expressing the panendothelial cell marker CD34 and number of blood vessels and stromal cells expressing ATX and AGK. In PVR membranes, spindle-shaped myofibroblasts expressing α-smooth muscle actin co-expressed ATX, AGK and LPA(1) receptor. CONCLUSIONS: The LPA/LPA(1) receptor pathway may be involved in inflammatory, angiogenic and fibrotic responses in proliferative vitreoretinal disorders.

The patient with an ocular prosthesis and his mirror image.

PURPOSE: In daily practice, it is often encountered that family and friends prefer the true image of the patient with an ocular prosthesis to the image in the mirror. Hence, when the patient looks at himself in the mirror, he may have the worst image of self. The authors studied the subjective difference between the mirror and true image of patients with an ocular prosthesis. METHODS: Controlled, prospective case series, including 16 patients with an ocular prosthesis and 16 healthy volunteers. The authors designed a double-mirror device that allowed the participant to see both his mirror and unreversed true image and asked the participants which image they preferred. In a slide show with pairs of the original and mirror-reversed photographs of the participants, they were asked which of the 2 photographs of each pair they preferred, of themselves and of the other participants. RESULTS: Of the patients, 100% preferred their mirror image and 79% their mirror-reversed photograph. Of the volunteers, these preferences were 81% and 60%, respectively. The volunteers significantly preferred the photograph of the patients with the ocular prosthesis on their left side. CONCLUSIONS: The patient with an ocular prosthesis prefers his mirror image. While judging unfamiliar faces, the right eye is considered to be more important in the case of abnormality.

Expression of high-mobility groups box-1/receptor for advanced glycation end products/osteopontin/early growth response-1 pathway in proliferative vitreoretinal epiretinal membranes.

PURPOSE: The high-mobility group box -1 (HMGB1)/receptor for advanced glycation end products (RAGE)/osteopontin (OPN)/early growth response-1 (Egr-1) pathway is involved in inflammation, angiogenesis, and fibrosis. We investigated the expression of the components of this pathway in proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR) epiretinal membranes. METHODS: Nine active and 13 inactive membranes from patients with PDR and 21 membranes from patients with PVR were studied by immunohistochemistry. RESULTS: In PDR membranes, vascular endothelial cells expressed HMGB1, RAGE, OPN, and Egr-1 in 21, 15, 20, and 16 membranes, respectively. Stromal cells expressed HMGB1, RAGE, OPN, and Egr-1 in 21, 20, 20, and 16 membranes, respectively. Significant correlations were detected between the number of blood vessels expressing the panendothelial cell marker CD34 and the number of blood vessels and stromal cells expressing HMGB1, RAGE, and OPN. The numbers of blood vessels and stromal cells expressing CD34, HMGB1, RAGE, and OPN and stromal cells expressing Egr-1 were significantly higher in active membranes than in inactive membranes. In PVR membranes, spindle-shaped myofibroblasts expressing α-smooth muscle actin coexpressed HMGB1, RAGE, OPN, and Egr-1. CONCLUSIONS: The HMGB1/RAGE/OPN/Egr-1 pathway may be involved in inflammatory, angiogenic and fibrotic responses in proliferative vitreoretinal disorders.

Expression of myofibroblast activation molecules in proliferative vitreoretinopathy epiretinal membranes.

PURPOSE: Fibrotic disorders are associated with activation of fibroblasts into extracellular matrix-secreting myofibroblasts expressing α-smooth muscle actin (α-SMA). Myofibroblasts are the predominant cellular component of proliferative vitreoretinopathy (PVR) epiretinal membranes. We investigated the expression of molecules involved in myofibroblast activation, migration and proliferation in PVR epiretinal membranes. METHODS: Fifteen membranes were studied by immunohistochemical techniques using monoclonal and polyclonal antibodies directed against snail, fibroblast activation protein (FAP), CD44, hydrogen peroxide-inducible clone-5 (Hic-5), galectin-3, interleukin-13 receptor α2 (IL-13Rα2) and receptor for advanced glycation end products (RAGE). RESULTS: Myofibroblasts expressing α-SMA were present in all membranes. Myofibroblasts expressed nuclear immunoreactivity for Snail and Hic-5, cytoplasmic immunoreactivity for FAP, IL-13Rα2 and RAGE and membranous immunoreactivity for CD44. There was no immunoreactivity for galectin-3. The number of cells expressing α-SMA correlated significantly with the number of cells expressing Snail (r = 0.56; p = 0.03), Hic-5 (r = 0.526; p = 0.044), IL-13Rα2 (r = 0.773; p = 0.001) and RAGE (r = 0.734; p = 0.002). CONCLUSIONS: Snail, FAP, CD44, Hic-5, IL13Rα2 and RAGE may be involved in proliferative events occurring in PVR.

Expression of advanced glycation end products and related molecules in diabetic fibrovascular epiretinal membranes.

PURPOSE: To investigate associations between expressions of advanced glycation end products (AGEs), transforming growth factor-beta (TGF-beta), tumour necrosis factor-alpha (TNF-alpha) and integrins and correlations between their expression and level of vascularization and proliferative activity in diabetic fibrovascular epiretinal membranes. METHODS: Membranes from eight patients with active proliferative diabetic retinopathy and nine patients with inactive proliferative diabetic retinopathy were studied by immunohistochemistry. RESULTS: Blood vessels expressed AGEs, TGF-beta, TNF-alpha and alpha(v)beta(3) integrin in 5, 13, 8 and 8 membranes, respectively. Stromal cells expressed AGEs, TNF-alpha and alpha(v)beta(3) integrin in 15, 13 and 3 membranes, respectively. There was no immunoreactivity for alpha(v)beta(5), alpha(5)beta(1) and alpha(2)beta(1) integrins. There were significant correlations between number of blood vessels expressing CD34 and number of blood vessels expressing AGEs (r(s) = 0.496; P = 0.043), TGF-beta (r(s) = 0.777; P < 0.001) and TNF-alpha (r(s) = 0.699; P = 0.002). There were significant correlations between number of blood vessels expressing AGEs and number of blood vessels expressing TGF-beta (r(s) = 0.532; P = 0.028) and TNF-alpha (r(s) = 0.626; P = 0.007). The correlation between number of blood vessels expressing TNF-alpha and alpha(v)beta(3) integrin was significant (r(s) = 0.617; P = 0.008). Number of blood vessels expressing CD34 (P = 0.001), TGF-beta (P = 0.006) and TNF-alpha (P = 0.002) and stromal cells expressing AGEs (P = 0.001) and TNF-alpha (P = 0.004) were significantly higher in active membranes than in inactive membranes. CONCLUSION: Interactions of AGEs, TGF-beta, TNF-alpha and alpha(v)beta(3) integrin might be involved in pathogenesis of proliferative diabetic retinopathy fibrovascular proliferation.

Expression of angiogenic and fibrogenic factors in proliferative vitreoretinal disorders.

PURPOSE: To investigate the expression of connective tissue growth factor (CTGF) in the retina of human subjects with diabetes mellitus, and CTGF, CD105, and gelatinase B in proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR) epiretinal membranes. METHODS: Twelve donor eyes from six subjects with diabetes mellitus, 10 eyes from five nondiabetic subjects, 14 PDR membranes, and five PVR membranes were studied by immunohistochemical techniques. In situ zymography was used to examine gelatinolytic activity in four PDR membranes. RESULTS: In nondiabetic retinas, there was no immunoreactivity for CTGF. Diabetic retinas showed immunoreactivity for CTGF in ganglion cells and microglia. Vascular endothelial cells in PDR membranes expressed CTGF, CD105, and gelatinase B in 10 (71.4%), 11 (78.6%), and 5 (35.7%) membranes, respectively. Myofibroblasts in PDR membranes expressed CTGF, and gelatinase B in 14 (100%), and 6 (42.9%) membranes, respectively. There was a significant correlation between the number of blood vessels expressing the panendothelial marker CD34 and the number of blood vessels expressing CTGF (r = 0.7884; P = 0.0008), and CD105 (r = 0.6901; P = 0.0063), and the number of myofibroblasts expressing CTGF (r = 0.5922; P = 0.0257). There was a significant correlation between the number of myofibroblasts expressing alpha-smooth muscle actin and the number of myofibroblasts expressing CTGF (r = 0.8393; P = 0.0002). In situ zymography showed the presence of gelatinolytic activity in vascular endothelial cells in PDR membranes. Myofibroblasts in PVR membranes expressed CTGF, and gelatinase B. CONCLUSIONS: These results suggest a possible role of CTGF, CD105, and gelatinase B in the pathogenesis of proliferative vitreoretinal disorders.

Expression of hypoxia-inducible factor-1alpha and the protein products of its target genes in diabetic fibrovascular epiretinal membranes.

AIMS: To investigate the expression of the hypoxia-inducible factor-1alpha (HIF-1alpha) and the protein products of its target genes vascular endothelial growth factor (VEGF), erythropoietin (Epo) and angiopoietins (Angs), and the antiangiogenic pigment epithelium-derived factor (PEDF) in proliferative diabetic retinopathy (PDR) epiretinal membranes. METHODS: Sixteen membranes were studied by immunohistochemical techniques. RESULTS: Vascular endothelial cells expressed HIF-1alpha, Ang-2 and VEGF in 15 (93.75%), 6 (37.5%) and 9 (56.25%) membranes, respectively. There was no immunoreactivity for Epo, Ang-1 and PEDF. There were significant correlations between the number of blood vessels expressing the panendothelial marker CD34 and the numbers of blood vessels expressing HIF-1alpha (r = 0.554; p = 0.026), Ang-2 (r = 0.830; p<0.001) and VEGF (r = 0.743; p = 0.001). The numbers of blood vessels expressing Ang-2 and VEGF in active membranes were higher than that in inactive membranes (p = 0.015 and 0.028, respectively). CONCLUSIONS: HIF-1alpha, Ang-2 and VEGF may play an important role in the pathogenesis of PDR. The findings suggest an adverse angiogenic milieu in PDR epiretinal membranes favouring aberrant neovascularisation and endothelial abnormalities.

Expression of apoptosis markers in the retinas of human subjects with diabetes.

PURPOSE: To investigate the expression of the apoptotic mediators in the retinas from human subjects with diabetes mellitus. METHODS: Ten donor eyes from five subjects with diabetes mellitus, and eight eyes from four nondiabetic subjects without known ocular disease serving as control subjects were examined. Immunohistochemical techniques were used with antibodies directed against glial fibrillary acidic protein (GFAP), caspase-3, Fas, Fas ligand (FasL), Bax, Bcl-2, survivin, p53, extracellular signal-regulated kinases (ERK1/2), and p38. RESULTS: In retinas from all subjects without diabetes, weak Bcl-2 immunoreactivity was confined to GFAP-positive glial cells in the nerve fiber layer. Weak immunoreactivity for ERK1/2 was noted in a few nuclei in the inner nuclear layer and in a few Müller cell processes. Cytoplasmic immunostaining for survivin was noted in the retinal pigment epithelial cells. There was no immunoreactivity for the other antibodies tested. All diabetic retinas showed cytoplasmic immunoreactivity for caspase-3, Fas, and Bax in ganglion cells. FasL immunoreactivity was detected in GFAP-positive cells. Upregulation of Bcl-2 immunoreactivity was noted in GFAP-positive cells in nerve fiber and ganglion cell layers, and Bcl-2 induction was noted in Müller cell processes. Strong immunoreactivity for ERK1/2 was observed in many nuclei in the inner nuclear layer in GFAP-positive cells in the nerve fiber and ganglion cell layers and numerous Müller cell processes. Survivin immunoreactivity was not altered in the diabetic retinas. There was no immunoreactivity for p53 and p38. CONCLUSIONS: Ganglion cells in diabetic retinas express several proapoptosis molecules, suggesting that these cells are the most vulnerable population. Glial cells in diabetic retinas are activated and express several antiapoptosis molecules in addition to the cytotoxic effector molecule FasL, suggesting a possible role of glial cells in induction of apoptosis in ganglion cells.

The T-lymphocyte chemoattractant Mig is highly expressed in vernal keratoconjunctivitis.

PURPOSE: To examine the expression of the three interferon-gamma-inducible CXCR3-binding chemokines, CXCL10/IP-10 (interferon-gamma-inducible protein of 10 KDa), CXCL9/Mig (monokine induced by interferon-gamma), and CXCL11/I-TAC (interferon-inducible T-cell alpha chemoattractant) in the conjunctiva of patients with vernal keratoconjunctivitis (VKC). These chemokines exhibit potent T-lymphocyte chemoattractant activity. DESIGN: Immunohistochemical study. METHODS: Conjunctival biopsy specimens from 16 patients with active VKC and nine control subjects were studied by immunohistochemical techniques using monoclonal antibodies directed against IP-10, Mig, and I-TAC. The phenotype of inflammatory cells expressing chemokines was examined by double immunohistochemistry. RESULTS: In the normal conjunctiva, very weak Mig immunoreactivity was observed on basal epithelial cells and on vascular endothelial cells in the upper substantia propria. There was no immunoreactivity for the other chemokines. In all VKC specimens, strong immunoreactivity for Mig was expressed by epithelial cells, vascular endothelial cells, and inflammatory mononuclear cells. Inflammatory mononuclear cells expressing IP-10 and I-TAC were noted in 10 and nine specimens, respectively. The numbers of Mig(+) inflammatory cells were significantly higher than the numbers of IP-10(+) and I-TAC(+) inflammatory cells (P <.001). Inflammatory cells expressing Mig were CD4(+) T-helper/inducer cells (71.6 +/- 3.2%), CD8(+) T-cytotoxic/suppressor cells (19.5 +/- 1.5%), and CD68(+) monocytes/macrophages (5.3 +/- 5%). All inflammatory cells expressing IP-10 and I-TAC were CD68(+) monocytes/macrophages. CONCLUSIONS: The CXC chemokine Mig is selectively and highly expressed in VKC suggesting a pathogenic role of the chemokine receptor CXCR3 and the ligand Mig in the recruitment of activated T lymphocytes.

A comparison of the efficacy and tolerability of olopatadine hydrochloride 0.1% ophthalmic solution and cromolyn sodium 2% ophthalmic solution in seasonal allergic conjunctivitis.

BACKGROUND: Treatments for allergic conjunctivitis have various mechanisms of action. Cromolyn sodium stabilizes conjunctival mast cells by preventing calcium influx across the cell membrane, whereas olopatadine hydrochloride is both an antihistamine and a mast cell stabilizer. OBJECTIVE: This study compared the efficacy and tolerability of olopatadine and cromolyn in controlling the ocular signs and symptoms of seasonal allergic conjunctivitis. METHODS: This was a multicenter, randomized, double-masked, parallel-group trial. One group instilled olopatadine 0.1% ophthalmic solution and placebo BID, and the other instilled cromolyn 2% ophthalmic solution QID, both for 6 weeks. The formulation of cromolyn used in this study is currently available only in Europe and Australia. RESULTS: The intent-to-treat efficacy and safety analyses included 185 patients, 91 in the olopatadine group and 94 in the cromolyn group. At 30 minutes after the first instillation, respective decreases of approximately 30% and approximately 20% were reported in self-rated ocular itching and redness with both treatments; by 4 hours, itching had decreased by approximately 38% in both groups. Differences between treatments were not statistically significant. At 4 hours, redness had decreased by approximately 38% and approximately 26% in the respective treatment groups. By day 42, both treatments had produced significant reductions from baseline in ocular signs and symptoms; however, the reductions in itching and redness were significantly greater with olopatadine compared with cromolyn (both variables, P < 0.05). The difference in physicians' impression of overall improvement on days 30 and 42 significantly favored olopatadine over cromolyn (both days, P < 0.05). Most patients (62.2%) had reacted positively to grass pollen at baseline. The regression slopes correlating itching and redness with pollen count were 5 times lower for olopatadine compared with cromolyn (P = 0.002 and P = 0.016, respectively), indicating that olopatadine's efficacy increased as the pollen count increased. CONCLUSIONS: Six weeks' instillation of olopatadine 0.19% ophthalmic solution BID had a significantly greater effect on the ocular signs and symptoms of allergic conjunctivitis compared with 6 weeks' instillation of cromolyn 2% ophthalmic solution QID. Both treatments were well tolerated by patients in all age groups; however, olopatadine appeared to have better local tolerability in children aged <11 years.