| Psoriasis is a common, chronic skin disorder characterized by hyperproliferation of the epidermis, accumulation of inflammatory cells and angiogenesis. Research into the pathogenesis of psoriasis has mainly concentrated on the interplay between inflammatory cells and the proliferative epidermis. The earliest detectable changes in a developing psoriatic lesion are vascular changes which made us understand the mechanisms that vascular changes is fundamental to an elucidation of pathogenetic mechanisms in psoriasis. Microvascular changes within lesional skin include pronounced dilatation, tortuosity, increased permeability and endothelial cell proliferation within the venous limb of capillaries in the dermal papillae. Vascular proliferation in psoriasis is felt to be under the influence of angiogenic molecules which are considered to be epidermal in origin. These factors include bFGF, IL-8, TNF-a ^ 0, PDECOF etal. The angiogenic potential of vascular endothelial growth factor is well documented in tumors and it has been demonstrated to act as a potent and selective mitogen for endothelial cells. Monocyte Chemoattractant Protein 1 which was studied as a chemokine before has also been identified inflammatory angiogenic potential. We studied the distribution and production of VEGF and MCP-1 in the skin sample and serum of patients with psoriasis and in normal controls.Subjects and MethodsSerum levels of vascular endothelial growth factor and Monocyte Chemoattractant Protein 1 were tested in psoriasis(n=31, 23men, 8 women, mean age 44.9 years) and normal persons(n=28, 20 men, 8 women, mean age 39.0 years). None of the patients was receiving systemic or UV therapy. Blood samples were collected and centrifuged immediately.Paired biopsy specimens were obtained from both involved skin (n=29, 21men, 8 women, mean age 36.8 years) and uninvolved skin (n=10 8men ,2 women, mean age 38.1 years) of patients with psoriasis vulgaris. Following local anaesthesia with 2% lidocaine, uninvolved skin was biopsied at least 10cm from the edge of the nearest plaque. The clinical severity of psoriasis ,assessed using the psoriasis area and severity index (PASI), ranged between 1.6-25.5(mean 8.0?.3). The control group consisted of 10 healthy individuals ( 4men ,6 women, mean age 42.8 years) . All biopsies were snap frozen in OCT medium and stored at -70癈 until required. In this study , all psoriatic patients biopsied were in active stage. Biopsied regions had not been treated with cortisone or other antipsoriatic agents for at least 2 weeks.Levels of VEGF and MCP-1 in sera were measured using a commercially available quantitative Sandwich enzyme-linked monoclonal immunosorbent assay (R&D Systems Ltd , Abingon, Oxon. U.K.) The VEGF and MCP-1 values were expressed as ng/mL.Snap frozen samples were cut into 5um cryosections and stained with monoclonal anti-VEGFmouse IgG( 1:100 Santa Cruz ) and multiclonal anti- MCP-1 goat IgG(l:200 Santa Cruz ). Standard immunohistochemical method was used.Statistics (SPSS/PC)Chi square test was used to analyze the immunohistochemistry datas.Non-parameter test was used to compare differences of sera between patients with psoriasis and controls.Graphical methods and correlation were used to assess the relationships between PASI and VEGF and MCP-1.P<0.05 was considered statistically significant using a two-tail hypothesis.Results and ConclusionsThe results were as follows: (l)Serum levels of VEGF(614.4?76.2 ng/ml) were significantly raised in psoriasis as compared with normal control (424.0?83.3ng/ml)(P<0.01). (2) Serum levels of MCP-1 (205.3?79.4 ng/ml) were raised in psoriasis as compared with normal control (176.3?09.3 ng/ml), but there was no significant difference between patients and controls(P>0.05). (3)Psoriasis has positive immunostaining for MCP-1 and VEGF which located to all the layers of the epidermis of involved skin. In the dermis, infiltrating cells and the blood vessels stained positive for MCP-1 and VEGF. In uninvolved skin the positiv...
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