基质金属蛋白酶-8在寻常型银屑病患者血清及皮损中的表达研究

Expression of matrix metalloproteinase 8 in the serum and skin lesions of patients with psoriasis vulgaris

目的:探究基质金属蛋白酶-8(MMP-8)在寻常型银屑病(PV)炎症反应中的作用。方法:将20例PV患者根据银屑病面积和严重程度指数(PASI)分为轻度组6例、中度组6例及重度组8例。用ELISA法检测并比较PV患者组及正常对照组(12例)血清中MMP-8浓度;用荧光定量PCR扩增并比较不同病情严重程度组间皮损处以及外观正常的周边皮肤MMP-8相对表达量;用免疫组化法观察MMP-8在皮损部位的分布状况。结果:血清MMP-8浓度比较:轻度组明显低于对照组(t=2.54,P=0.022)、重度组(t=2.69,P=0.020)。PV患者皮损部位MMP-8表达明显高于皮损相邻部位外观正常的皮肤(t=2.91,P=0.009);重度组PV皮损部位MMP-8表达明显高于轻度组(t=3.45,P=0.005)及中度组(t=2.74,P=0.018)。在PV皮损部位,MMP-8主要表达于表皮基底细胞及棘细胞,而在皮损周边部位,MMP-8在基底细胞中表达较明显。真皮中MMP-8主要表达于小血管处。结论:MMP-8在炎症反应较强的皮损中表达上升,推测其通过调控炎症反应及促进血管新生等参与PV的免疫病理进程。

Objective:To assess the role of matrix metalloproteinase 8 in the inflammation of psoriasis vulgaris(PV). Methods:According to the psoriasis area and severity index(PASI), twenty PV patients were grouped into mild(n=6), moderate(n=6), and severe(n=8) groups. Serum levels of MMP-8, measured with ELISA, were compared among PV groups and the controls(n=12), while expression levels of MMP-8 mRNA were compared between lesional sites and their adjacent normal skin by qPCR. Localization of MMP-8 positive cells in the skin was determined by immunohistochemistry.Results:Serum MMP-8 concentration was significantly lower in the mild PV than in both the severe PV(t=2.69,P=0.020) and the controls(t=2.54,P=0.022). Expression levels of MMP-8 mRNA in the lesional sites were significantly higher than that in their adjacent normal skins(t=2.91,P=0.009). Moreover, expression levels of MMP-8 mRNA were significantly higher in the lesions of severe PV than that of mild(t=3.45, P=0.005) and moderate(t=2.74, P=0.018) PV. MMP-8 positive cells were mainly localized in the basal and spinous layers of the lesional skin, while in their adjacent normal skin, MMP-8 positive cells mainly located in the basal layer. In the dermis,high intensity of MMP-8 staining was observed in endothelial cells of papillary vessels.Conlusions: Increased expression of MMP-8 in inflammatory site of PV suggests the involvements of MMP-8 in immunoregulation and pro-angiogenesis.