The Charles Institute of Dermatology, University College Dublin, Belfield, Dublin 4, Ireland.
Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane, Dessau, Germany.
Br J Dermatol. 2018 Aug;179(2):420-430. doi: 10.1111/bjd.16540. Epub 2018 Jun 1.
Rosacea is a common facial skin disorder mainly affecting middle-aged adults. Its aetiology is unknown and pathogenesis uncertain. Activation of the host innate immune response has been identified as an important factor. The Demodex mite population in the skin of rosacea patients is significantly higher than in patients with normal skin, suggesting that they may be of aetiological importance in this disorder.
To determine the potential of Demodex mites to interact with the host immune system.
Live Demodex mites were extracted from normal facial skin of control subjects and used in cell stimulation experiments with the immortalized SZ95 sebocyte line. Time- and mite-dose-dependent experiments were performed. Direct effects of Demodex and effects of the medium in which Demodex had been cultured were evaluated on the Toll-like receptor (TLR) signalling pathway on both a gene and protein expression level.
Mites modulated TLR signalling events on both mRNA and protein levels in SZ95 sebocytes. An initial trend towards downmodulation of genes in this pathway was observed. A subsequent switch to positive gene upregulation was recorded after 48 h of coculture. Demodex secreted bioactive molecules that affected TLR2 receptor expression by sebocytes. High numbers of Demodex induced proinflammatory cytokine secretion, whereas lower numbers did not.
Demodex mites have the capacity to modulate the TLR signalling pathway of an immortalized human sebocyte line. Mites have the capacity to secrete bioactive molecules that affect the immune reactivity of sebocytes. Increasing mite numbers influenced interleukin-8 secretion by these cells.
酒渣鼻是一种常见的面部皮肤疾病，主要影响中年成年人。其病因不明，发病机制不确定。宿主固有免疫反应的激活已被确定为一个重要因素。酒渣鼻患者皮肤中的蠕形螨种群明显高于正常皮肤患者，这表明它们在这种疾病中可能具有病因学意义。
确定蠕形螨与宿主免疫系统相互作用的潜力。
从正常面部皮肤中提取活的蠕形螨来自对照组的受试者，并用于永生化 SZ95 皮脂细胞系的细胞刺激实验。进行了时间和螨虫剂量依赖性实验。评估了在基因和蛋白质表达水平上，直接作用于 Demodex 和其在培养中使用的培养基对 Toll 样受体 (TLR) 信号通路的影响。
螨虫在 SZ95 皮脂细胞中调节 TLR 信号通路的基因和蛋白质水平。在该途径中观察到最初的下调趋势。随后在共培养 48 小时后记录到正向基因上调。Demodex 分泌的生物活性分子通过皮脂细胞影响 TLR2 受体表达。大量的 Demodex 诱导促炎细胞因子的分泌，而较少的则不会。
蠕形螨具有调节永生化人皮脂细胞系 TLR 信号通路的能力。螨虫具有分泌生物活性分子的能力，这些分子影响皮脂细胞的免疫反应性。螨虫数量的增加影响这些细胞分泌白细胞介素-8。
