Development of Monoclonal Antibody-based Assays for Detection and Qualification of Artemisinin Derivatives

以青蒿素为基础的联合疗法在当前的疟疾控制和消除运动中发挥着至关重要的作用。然而，假冒伪劣青蒿素的流通严重威胁着疟疾防治工作。不含或几乎不含有效成分的假青蒿素会危及生命，而不合格的药物则会促进耐药性的产生。这一“致命问题”的规模在一些东南亚国家尤为严重，那里市场上销售的青蒿素中有多达64%是假的。为了延长治疗疟疾的青蒿素药物的寿命，这些国家需要实施严格的药物质量控制。为此，需要快速可靠的青蒿素检测和定量方法。传统的青蒿素定量方法往往需要昂贵的仪器和大量的技术支持，而用于筛选假青蒿素衍生物的快速定性方法灵敏度和可变性较低。基于我们最近成功开发了一种高灵敏度和可靠的针对青蒿素的单克隆抗体酶联免疫吸附试验（ELISA），我们建议1)利用创新的免疫原设计开发一系列具有特异性的主要青蒿素衍生物（双氢青蒿素、蒿甲醚、蒿醚和青蒿琥酯）的单克隆抗体，2)开发和优化用于精确定量青蒿素的ELISA。3)使用这些新工具对三个东南亚国家以青蒿素为基础的抗疟药物的药物质量进行系统的实地调查；4)优化ELISA条件，使其可作为药代动力学研究中青蒿素及其衍生物定量的替代工具。

Artemisinin-based combination therapies (ACTs) play an essential role in the current malaria control and elimination campaign. However, the circulation of counterfeit and substandard artemisinins greatly threatens the malaria control efforts. Fake artemisinins containing no or little active ingredients are life-threatening, while substandard drugs encourage resistance development. The scale of this 'lethal problem' is particularly huge in some Southeast Asian countries, where as much as 64% of the artesunate sold on the market was fake. To prolong the life span of artemisinin drugs for treating malaria, strict drug quality control needs to be implemented in these nations. For this purpose, fast and reliable methods of artemisinin detection and quantitation are needed. Traditional methods for quantitation of artemisinins often require expensive instruments and substantial technical support, whereas the rapid qualitative method for screening of fake artemisinin derivatives is less sensitive and variable. Based on our recent success of developing a highly sensitive and reliable enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody against artemisinins, we propose to 1) develop a series of monoclonal antibodies with specificities for the major artemisinin derivatives (dihydroartemisinin, artemether, arteether, and artesunate) using an innovative design of immunogens, 2) develop and optimize an ELISA for accurate quantification of artemisinins, and a lateral flow dipstick assay for rapid, semi-quantitative analysis of artemisinins in antimalarial drugs, 3) perform systematic field surveys of the drug quality of artemisinin-based antimalarial medicines in three Southeast Asian countries using these new tools, and 4) optimize the ELISA conditions so that it can be used as an alternative tool for quantification of artemisinins and its derivatives in pharmacokinetic studies. These immunoassays will offer convenient tools for both accurate quantification of artemisinins and rapid detection of counterfeit and substandard artemisinin derivative drugs, contributing to antimalarial drug quality control.