PDF(Pubmed)
Abstract：
C3 glomerulopathies (C3G) are ultra-rare complement-mediated diseases that lead to end-stage renal disease (ESRD) within 10 years of diagnosis in ~50% of patients. Overactivation of the alternative pathway (AP) of complement in the fluid phase and on the surface of the glomerular endothelial glycomatrix is the underlying cause of C3G. Although there are animal models for C3G that focus on genetic drivers of disease, in vivo studies of the impact of acquired drivers are not yet possible.
Here we present an in vitro model of AP activation and regulation on a glycomatrix surface. We use an extracellular matrix substitute (MaxGel) as a base upon which we reconstitute AP C3 convertase. We validated this method using properdin and Factor H (FH) and then assessed the effects of genetic and acquired drivers of C3G on C3 convertase.
We show that C3 convertase readily forms on MaxGel and that this formation was positively regulated by properdin and negatively regulated by FH. Additionally, Factor B (FB) and FH mutants impaired complement regulation when compared to wild type counterparts. We also show the effects of C3 nephritic factors (C3Nefs) on convertase stability over time and provide evidence for a novel mechanism of C3Nef-mediated C3G pathogenesis.
We conclude that this ECM-based model of C3G offers a replicable method by which to evaluate the variable activity of the complement system in C3G, thereby offering an improved understanding of the different factors driving this disease process.
Here we present an in vitro model of AP activation and regulation on a glycomatrix surface. We use an extracellular matrix substitute (MaxGel) as a base upon which we reconstitute AP C3 convertase. We validated this method using properdin and Factor H (FH) and then assessed the effects of genetic and acquired drivers of C3G on C3 convertase.
We show that C3 convertase readily forms on MaxGel and that this formation was positively regulated by properdin and negatively regulated by FH. Additionally, Factor B (FB) and FH mutants impaired complement regulation when compared to wild type counterparts. We also show the effects of C3 nephritic factors (C3Nefs) on convertase stability over time and provide evidence for a novel mechanism of C3Nef-mediated C3G pathogenesis.
We conclude that this ECM-based model of C3G offers a replicable method by which to evaluate the variable activity of the complement system in C3G, thereby offering an improved understanding of the different factors driving this disease process.
摘要：
未经证实：C3肾小球疾病（C3G）是极罕见的补体介导的疾病，在约50％的患者诊断后10年内导致终末期肾病（ESRD）。补体在液相和肾小球内皮糖基质表面的替代途径（AP）的过度激活是C3G的根本原因。尽管有C3G的动物模型关注疾病的遗传驱动因素，目前尚不可能对获得性驱动因素的影响进行体内研究。
UNASSIGNED：在这里，我们提出了在糖基质表面上AP激活和调节的体外模型。我们使用细胞外基质替代物（MaxGel）作为基础，在此基础上重建APC3转化酶。我们使用备解素和因子H（FH）验证了该方法，然后评估了C3G的遗传和获得性驱动因素对C3转化酶的影响。
UNASSIGNED:我们表明C3转化酶容易在MaxGel上形成，并且这种形成受备解素正调节，受FH负调节。此外,当与野生型对应物相比时,因子B(FB)和FH突变体损害补体调节。我们还显示了C3肾病因子（C3Nefs）随时间对转化酶稳定性的影响，并为C3Nef介导的C3G发病机制提供了新的证据。
UNASSIGNED：我们得出结论，这种基于ECM的C3G模型提供了一种可复制的方法，通过该方法可以评估C3G中补体系统的可变活性，从而提供了对驱动这种疾病过程的不同因素的更好的理解。
UNASSIGNED：在这里，我们提出了在糖基质表面上AP激活和调节的体外模型。
UNASSIGNED:我们表明C3转化酶容易在MaxGel上形成，并且这种形成受备解素正调节，受FH负调节。
UNASSIGNED：我们得出结论，这种基于ECM的C3G模型提供了一种可复制的方法，通过该方法可以评估C3G中补体系统的可变活性，
