ABSTRACT
PURPOSE: Various cytokines, including tumor necrosis factor-alpha (TNF-α), Fas ligand (FasL), interleukin-1α (IL-1α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6), contribute to the pathogenesis of primary open angle glaucoma (POAG). The present study was set to measure these cytokines in the aqueous humor of patients with POAG and in control subjects using multiplex bead analysis. METHODS: Twenty-five patients with POAG and 29 control subjects were enrolled in this case-control study. Aqueous humor concentrations of the cytokines (IL-1 α, IL-1 ß, IL-6, FasL, and TNF- α) were measured using multiplex bead analysis. RESULTS: Mean aqueous humor levels of IL-6 were significantly lower in patients with POAG compared to the control subjects (9.3±23.7 versus 55.3±94.4 pg/ml; p=0.002). No significant difference in the aqueous humor concentration of IL-1ß was found between patients with POAG and control subjects (0.5±0.8 versus 0.4±0.8 pg/ml; p=0.85.) Concentrations of IL-1α, TNF-α, and FasL were below limits of detection. No significant correlation was found between IL-6 concentration and age, duration of disease, cup/disc ratio, or mean deviation. CONCLUSIONS: In the present study, we found significantly lower concentrations of IL-6 in the aqueous humor of patients with POAG.
Subject(s)
Aqueous Humor/metabolism , Fas Ligand Protein/metabolism , Glaucoma, Open-Angle/metabolism , Immunoassay/methods , Interleukin-1alpha/metabolism , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Tumor Necrosis Factor-alpha/metabolism , Aged , Cataract/metabolism , Female , Humans , MaleABSTRACT
PURPOSE: To investigate the role of inflammatory and angiogenic factors in the pathogenesis of diabetic retinopathy, we determined, in diabetic patients and controls, vitreous and serum concentrations of interferon-induced protein (IP)-10, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, regulated upon activation, normal T-expressed and secreted (RANTES), and vascular endothelial growth factor (VEGF). METHODS: We recruited 36 probands with type 2 diabetes mellitus (15 noninsulin-dependent and 21 insulin-dependent) and 69 normal controls. Using Cytometric Bead Array Technology, we measured vitreous and serum concentrations of IP-10, MCP-1, MIP-1alpha, MIP-1beta, RANTES, and VEGF. RESULTS: In diabetic patients the mean vitreous levels of IP-10, MCP-1 and VEGF were significantly higher compared normal controls. [IP-10 (pg/mL) 254.84 +/-311.67 versus 78.90 +/- 67.94 (p<0.001); MCP-1 (pg/mL) 1127.14 +/- 738.91 versus 700.80 +/-419.21 (p=0.002); VEGF (pg/mL) 954.98 +/- 2315.09 versus 37.90 +/- 28.51(p<0.001)]. Vitreous levels of VEGF correlated with vitreous levels of both IP-10 and MCP-1 (p<0.05). MIP-1beta, RANTES, and VEGF mean serum levels were significantly raised in diabetic probands while IP-10, MCP-1, and MIP-1alpha serum levels showed no significant elevation compared to controls [IP-10 (pg/mL) 346.20 +/- 287.36 versus 328.74 +/-352.35 (p=0.88); MCP-1(pg/mL) 133.10 +/- 89.10 versus 141.47 +/- 222.15 (p=0.50); MIP-1beta (pg/mL) 184.40 +/- 100.20 versus 139.56 +/- 151.38 (p=0.003); RANTES (pg/mL) 51336.23 +/- 19940.31 versus 33629.2 +/- 33301.0 (p=0.002); VEGF (pg/mL) 304.88 +/- 257.52 versus 154.45 +/- 114.78 (p<0.001)]. CONCLUSIONS: Our results suggest that in diabetics, there is an upregulation of IP-10, MCP-1, and VEGF in the vitreous and an upregulation of MIP-1beta, RANTES, and VEGF in the serum. These findings support the concept of an angiogenic and inflammatory element in the development of diabetic retinopathy.
Subject(s)
Angiogenesis Inducing Agents/metabolism , Diabetes Mellitus/metabolism , Inflammation Mediators/metabolism , Vitreous Body/metabolism , Aged , Angiogenesis Inducing Agents/blood , Chemokine CCL2/metabolism , Chemokine CCL4/blood , Chemokine CCL5/blood , Chemokine CXCL10/metabolism , Diabetes Mellitus/blood , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 2/metabolism , Female , Humans , Inflammation Mediators/blood , Male , Middle Aged , Osmolar Concentration , Up-Regulation , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor A/metabolismABSTRACT
PURPOSE: This study was carried out to compare cytometric bead array (CBA) technology with conventional enzyme linked immunosorbent assay (ELISA) for the measurement of both vitreous and serum concentrations of interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), and angiogenin (ANG) in diabetic and non-diabetic patients. METHODS: Measurement of vitreous and serum concentrations of IL-8, VEGF, and ANG using both ELISA and CBA was performed in 26 probands (13 diabetics and 13 non-diabetic control subjects). RESULTS: Vitreous and serum concentrations of IL-8, VEGF, and ANG determined by CBA showed a strong correlation with those measured by ELISA. Vitreous levels of IL-8, VEGF, and ANG were significantly higher in diabetics compared to non-diabetic control subjects. No significant correlation between vitreous and serum levels of any of the investigated parameters were found in either diabetics or control individuals. CONCLUSIONS: The present study is the first to utilize cytometric bead array technology for the measurement of angiogenic factors in the vitreous. Measurements obtained by ELISA and CBA technologies were highly correlated for IL-8, VEGF, and ANG in both vitreous and serum samples. Diabetic individuals showed significant elevation of IL-8, VEGF, and ANG in the vitreous but not in serum samples compared to control subjects. The most striking advantage of the CBA technology is the fact that numerous parameters can be measured in parallel using a comparatively small sample volume. It is therefore more rapid and cost effective than ELISA technology. CBA technology is a new, accurate method to measure IL-8, VEGF, and ANG in the vitreous.
