The complement system (CS) is an integral part of innate immunity and can be activated via three different pathways. The alternative pathway (AP) has a central role in the function of the CS. The AP of complement system is implicated in several human disease pathologies. In the absence of triggers, the AP exists in a time-invariant resting state (physiological steady state). It is capable of rapid, potent and transient activation response upon challenge with a trigger. Previous models of AP have focused on the activation response. In order to understand the molecular machinery necessary for AP activation and regulation of a physiological steady state, we built parsimonious AP models using experimentally supported kinetic parameters. The models further allowed us to test quantitative roles played by negative and positive regulators of the pathway in order to test hypotheses regarding their mechanisms of action, thus providing more insight into the complex regulation of AP.

中文翻译：

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补体系统替代途径的数学建模

补体系统 (CS) 是先天免疫的组成部分，可以通过三种不同的途径激活。替代途径 (AP) 在 CS 的功能中起核心作用。补体系统的 AP 与几种人类疾病病理有关。在没有触发因素的情况下，AP 处于不随时间变化的静息状态（生理稳态）。它能够在受到触发器的挑战时做出快速、有效和瞬时的激活反应。以前的 AP 模型侧重于激活响应。为了了解 AP 激活和生理稳态调节所必需的分子机制，我们使用实验支持的动力学参数建立了简约的 AP 模型。