METHODS: Cryopreserved Guillain-Barré syndrome (GBS) patient sural nerve biopsies and sciatic nerves from the severe murine experimental autoimmune neuritis (sm-EAN) GBS model were studied. Cultured conditional ready MHC Class II antigen A-alpha chain (H2-Aa) embryonic stem cells were used to generate H2-Aaflox/+ C57BL/6 mice. Mice were backcrossed and intercrossed to the SJL background to generate H2-Aaflox/flox SJL mice, bred with hemizygous Tamoxifen-inducible von Willebrand factor Cre recombinase (vWF-iCre/+) SJL mice to generate H2-Aaflox/flox; vWF-iCre/+ mice to study microvascular endothelial cell adaptive immune responses. Sm-EAN was induced in Tamoxifen-treated H2-Aaflox/flox; vWF-iCre/+, H2-Aaflox/flox; +/+, H2-Aa+/+; vWF-iCre/+ and untreated H2-Aaflox/flox; vWF-iCre/+ adult female SJL mice. Neurobehavioral, electrophysiological and histopathological assessments were performed at predefined time points.
RESULTS: Endoneurial endothelial cell MHC class II expression was observed in normal and inflamed human and mouse peripheral nerves. Tamoxifen-treated H2-Aaflox/flox; vWF-iCre/+ mice were resistant to sm-EAN despite extensive MHC class II expression in lymphoid and non-lymphoid tissues.
CONCLUSIONS: A conditional MHC class II knockout mouse to study cell- and time-dependent adaptive immune responses in vivo was developed. Initial studies show microvascular endothelial cell MHC class II expression is necessary for peripheral nerve specific autoimmunity, as advocated by human in vitro adaptive immunity and ex vivo transplant rejection studies.
方法:研究了冷冻保存的格林-巴利综合征(GBS)患者的腓肠神经活检和来自严重小鼠实验性自身免疫性神经炎(sm-EAN)GBS模型的坐骨神经。使用培养的条件就绪型MHCII类抗原A-α链(H2-Aa)胚胎干细胞产生H2-Aaflox/+C57BL/6小鼠。将小鼠回交并与SJL背景杂交以产生H2-Aaflox/floxSJL小鼠,用半合子他莫昔芬诱导的血管性血友病因子Cre重组酶(vWF-iCre/)SJL小鼠繁殖以产生H2-Aaflox/flox;vWF-iCre/小鼠研究微血管内皮细胞适应性免疫反应。在他莫昔芬处理的H2-Aaflox/flox中诱导Sm-EAN;vWF-iCre/+,H2-Aaflox/flox;+/+,H2-Aa+/+;vWF-iCre/+和未处理的H2-Aaflox/flox;vWF-iCre/+成年雌性SJL小鼠。神经行为学,在预定时间点进行电生理学和组织病理学评估.
结果:在正常和发炎的人和小鼠周围神经中观察到了II类MHC的内皮细胞表达。他莫昔芬处理的H2-Aaflox/flox;vWF-iCre/小鼠对sm-EAN具有抗性,尽管MHCII类在淋巴组织和非淋巴组织中广泛表达。
结论:开发了一种条件性MHCII类基因敲除小鼠,用于研究体内细胞和时间依赖性的适应性免疫反应。初步研究显示微血管内皮细胞MHCⅡ类的表达是周围神经特异性自身免疫所必需的,正如人类体外适应性免疫和离体移植排斥研究所倡导的那样。