Toll-Like Receptors and Vascular Markers in Ocular Rosacea
ABSTRACT To delineate signals by which the vascular abnormalities inherent to ocular rosacea arise and to correlate these signals with elements of the innate immune system.
Experimental study. Immunohistochemical staining was performed for a variety of vascular markers and for toll-like receptor-4 on eyelid biopsies taken from patients with ocular rosacea and normal controls. Statistical comparisons were then performed between the 2 groups.
Immunohistochemical staining for CD31 and integrin-β-3 did not demonstrate any statistically significant differences between eyelids from patients with ocular rosacea and normal controls. Cutaneous biopsies from ocular rosacea patients demonstrated statistically significant enrichments of intercellular adhesion molecule-1 and CD105 among arterioles, whereas there were no statistically significant differences in the venules between normal controls and ocular rosacea patients. The correlation between the number of toll-like receptor-4-positive cells and each vascular marker was statistically significant.
Cutaneous biopsies of the eyelid did not demonstrate an increase in the total number of blood vessels. However, the vascular abnormalities that are typical of ocular rosacea represent activated, inflamed vessels, and these phenomena may be mediated by intercellular adhesion molecule and CD105. Furthermore, the strong correlations between toll-like receptor-4 and each vascular marker suggest that the innate immune system may govern the cutaneous effects of ocular rosacea. Intercellular adhesion molecule, CD105, and toll-like receptor-4 may represent important therapeutic targets in the management of this disease.
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ABSTRACT: The metabolism of [1-14C]eicosatetraenoic (arachidonic, 20:4(n - 6)), [1-14C]tetracosatetraenoic (24:4(n - 6)) and [1-14C]triacontatetraenoic (30:4(n - 6)) acids was studied in intact human neutrophils. [1-14C]20:4(n - 6) and [1-14C]24:4(n - 6) were efficiently taken up by the neutrophils, esterified into neutral lipids and phospholipids, and elongated by up to four carbon units. In contrast, [1-14C]30:4(n - 6) was poorly incorporated into the cells and remained predominantly in the original unesterified form. The [1-14C]tetraenoic fatty acids were mainly esterified into triacylglycerol, suggesting that this lipid class is important in the intracellular trafficking of polyunsaturated fatty acids. The leukocytes demonstrated a low capacity to beta-oxidize and desaturate the fatty acid substrates. In the presence of calcium ionophore A23187 the neutrophils converted [1-14C]20:4(n - 6) to a variety of radiolabelled oxygenated fatty acid derivatives including prostaglandins, thromboxanes, mono- and dihydroxylated fatty acids and leukotrienes. The major eicosanoid products were 5-monohydroxy-20:4(n - 6) and leukotriene B4. In contrast, [1-14C]24:4(n - 6) was metabolized to radiolabelled monohydroxylated fatty acids (predominantly the 9-hydroxy positional isomer) but not to other lipoxygenase or cyclooxygenase products by the calcium ionophore-stimulated cells. Negligible oxygenated fatty acid compounds were formed from [1-14C]30:4(n - 6), indicating that it is a poor substrate for the neutrophil cyclooxygenase and lipoxygenase enzymes.Biochimica et Biophysica Acta 09/1994; 1213(3):325-34. DOI:10.1016/0005-2760(94)00059-X · 4.66 Impact Factor
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ABSTRACT: T-cell activation through T-cell receptor engagement requires co-stimulatory molecules and also adhesion molecules such as ICAM-1. Moreover ICAM-1 mediates leukocyte invasion from the blood into tissue during inflammatory processes. In animal studies using mouse monoclonal antibodies against ICAM-1 (enlimomab), renal allograft survival has been improved and reperfusion damage from ischemia reduced. The European Anti-ICAM-1 Renal Transplant Study (EARTS) was a randomized, double-blind, parallel-group, placebo-controlled study lastingl year and performed in 10 transplant centers in Europe. A total of 262 recipients of cadaveric kidneys were given either enlimomab or a placebo for 6 days and were given triple immunosuppressive therapy of cyclosporine, azathioprine, and prednisolone. The primary efficacy endpoint was the incidence of the first acute rejection within 3 months, and each event was assessed by a committee including investigators and independent pathologists. There was no significant difference in the incidences of first acute rejection at 3 months between the placebo and enlimomab groups (39% vs. 45%), and enlimomab did not reduce the risk of delayed onset of graft function (DGF) (26% vs. 31%). Neither was there a difference in patient survival (95% vs. 91%) or graft survival (89% vs. 84%) at 1 year. Fatal events occurred in 19 (7%) patients (7 placebo, 12 enlimomab). Clinically, the most important non-fatal adverse events were infections; however, there was no statistically significant difference between the incidences in the two groups (70% vs. 79%). Short term enlimomab induction therapy after renal transplantation did not reduce the rate of acute rejection or DGF.Transplantation 04/1999; 67(5):729-36. DOI:10.1097/00007890-199903150-00015 · 3.78 Impact Factor
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ABSTRACT: Endoglin (EDG; CD105) is a proliferation-associated cell membrane antigen of endothelial cells and is strongly expressed on the tumor-associated angiogenic vascular endothelium. Furthermore, EDG is essential for angiogenesis and a component of the transforming growth factor (TGF)-beta receptor complex. The present three anti-EDG monoclonal antibodies (mAbs), SN6f, SN6j, and SN6k, react strongly with proliferating human endothelial cells but cross-react very weakly with murine endothelial cells. Analysis of Scatchard plot of direct binding of these mAbs to proliferating human umbilical vein endothelial cells showed equilibrium constants of 8.3 x 10(9), 3.1 x 10(9), and 1.0 x 10(9) liter/mol, respectively, for SN6f, SN6j, and SN6k. These mAbs did not react with MCF-7 human breast cancer cells. To facilitate antiangiogenic tumor therapy by these mAbs in animal models, we used human skin/severe combined immunodeficiency (SCID) mouse chimeras bearing tumors of MCF-7. Blood vessels in the chimeras were analyzed by immunostaining with species (human or mouse)-specific anti-CD31 and anti-EDG mAbs including an antihuman EDG mAb termed SN6h. Blood vessels in the completely healed grafted human skins consisted of a mixture of human (43.5%) and murine (56.5%) vessels, whereas only murine vessels were detected in the adjacent murine skins and s.c. tissues. Therefore, murine vessels infiltrate into the human skin grafts from the adjacent murine tissues, whereas the growth of human vessels is limited within the boundary of human skins. Growth of human MCF-7 tumors in the human skin grafts increased the ratio of human:murine vessels. Analyses of the grafted skins before and after tumor transplantation showed that SN6h reacted with tumor-induced angiogenic blood vessels but not with nonangiogenic vessels, whereas antihuman CD31 mAb reacted with both angiogenic and nonangiogenic vessels. The results show that SN6h is capable of distinguishing the tumor-induced angiogenic vasculature from the nonangiogenic vasculature in the present model. Antiangiogenic therapy of the chimeras bearing established MCF-7 tumors was carried out by i.v. administration of a mAb(s) via the tail vein of mice. SN6j and SN6k were effective for suppressing the established tumors, whereas tumor suppression was weaker with SN6f. The results indicate an absence of a direct correlation between antigen-binding avidity and in vivo antitumor efficacy of anti-EDG mAbs and suggest the importance of other factors (e.g., epitopes) in antitumor efficacy. No significant toxicity of the mAbs was detected. Combination of SN6f and SN6k that define mutually nonoverlapping epitopes showed an additive antitumor effect. Combination of SN6j and cyclophosphamide using an antiangiogenic schedule of drug dosing showed synergistic antitumor efficacy. The combination therapy induced lasting complete regression of the established tumors in two of the eight treated chimeras. We examined human and murine blood vessels in large human tumors from the chimeras at the end of therapeutic experiment. The test showed that SN6j therapy resulted in complete suppression of human vessels in the tumors but resulted in only weak suppression of murine vessels. Cyclophosphamide was not effective for suppressing human vessels and only weakly suppressive against murine vessels. Combination of SN6j and cyclophosphamide was effective for completely suppressing human vessels and also effective for partial (i.e., 35%) suppression of murine vessels. The results show that systemic administration of naked antihuman EDG mAbs can suppress established tumors, and the efficacy is markedly enhanced by combining a chemotherapeutic drug using an antiangiogenic schedule of drug dosing. These mAbs should show stronger antitumor efficacy in patients whose tumors depend entirely on human blood vessels.Cancer Research 12/2001; 61(21):7846-54. · 9.28 Impact Factor