Evolutionary medicine in the development of antimalaria drugs

描述(申请人提供)：进化医学是进化思维在医学和医学研究中的应用。这种方法在传染病方面具有特殊的优点，在这些疾病中，进化对于理解毒力、免疫逃避、耐药性和其他在公共卫生和临床干预中至关重要的特征至关重要。这项建议采用进化的方法来评价用于开发三代三嗪二氢叶酸还原酶(DHFR)抑制剂的先导化合物。DHFR是用于防治疟疾的最有效的药物靶点之一。这个项目的目标有两个：(1)应用进化 考虑在知情的情况下选择最佳的先导化合物，以选择进一步开发成临床有效、治疗寿命长的药物；以及(2)在以下方面进行研究 这种方法可以探索耐药的适应性格局如何随着药物浓度的变化和对不同干扰因素的反应而发生变化。在具体目标1中，我们将检测恶性疟原虫和间日疟原虫的野生型等位基因和所有已知的自然发生的DHFR多态，以了解它们对五种潜在的第三代抗叶酸先导化合物的抗性。这些测试将使用酵母和细菌转基因DHFR表达系统。使用实验模型是必要的，因为间日疟原虫不能在实验室中培养，而且从时间和成本上来说，生产恶性疟原虫检测所需的同基因菌株是不可行的。在特定目标2中，我们将通过创建“缺失的中间”等位基因来加强特定目标1中的研究，以允许对作为扰动剂的每一种新的三嗪反叶酸盐的适应性景观进行完整的组合分析。在具体目标3中，我们将在恶性疟原虫和间日疟原虫转基因系统中进行突变和选择实验，以确定野生型等位基因或任何多态是否容易通过新的突变转化为对任何新的抗叶酸的抗性。这是评估新药潜在治疗寿命的一个关键问题。被测试的先导化合物是五种三嗪抗叶酸盐WR99210、JPC-2067、JPC-2122、JPC-1058和JPC-1054。这项研究将与雅各布斯制药公司合作进行，雅各布斯制药公司是一家小公司，但在开发和生产抗疟疾和弓形虫病的抗叶酸盐方面仍处于世界领先地位。我们的合作者大卫·P·雅各布斯医学博士在与学术研究人员的合作以及研究资源和信息的公开传播方面有着杰出的记录。这项研究是药物开发和进化生物学的独特结合，有可能为新的救命药物的开发做出贡献，同时揭示蛋白质进化的新原理。

DESCRIPTION (provided by applicant): Evolutionary Medicine is the application of evolutionary thinking to problems in medicine and medical research. This approach has exceptional merit in infectious diseases, in which evolution is critically important in understanding virulence, immune evasion, drug resistance, and other features critical in public health and clinical intervention. This proposal takes an evolutionary approach to the evaluation of lead compounds for the development of third-generation triazine inhibitors of the enzyme dihydrofolate reductase (DHFR). DHFR is one of the most effective drug targets used for the prevention and treatment of malaria. The goal of this project is twofold: (1) To apply evolutionary thinking to make informed choices of the best lead compounds to select for further development into clinically effective drugs with a long therapeutic lifetime; and (2) To perform the studies in such a way as to explore how adaptive landscapes of drug resistance change as a function of drug concentration and in response to differing perturbagens. In Specific Aim 1 we will examine the wildtype allele and all known naturally occurring polymorphisms in DHFR of P. falciparum and P. vivax for their resistance to five potential lead compounds for third-generation antifolates These tests will use both the yeast and bacterial transgenic DHFR expression systems. The use of experimental models is essential, as P. vivax cannot be cultured in the laboratory, and the production of the isogenic strains needed for the tests in P. falciparum is not feasible in regard to time or cost. In Specific Aim 2, we will augment the studies in Specific Aim 1 by creating the "missing intermediate" alleles to allow a complete combinatorial analysis of the adaptive landscape with respect to each of the novel triazine antifolates as perturbagens. In Specific Aim 3 we will carry out mutagenesis and selection experiments in the P. falciparum and P. vivax transgenic systems to determine whether the wildtype allele or any of the polymorphisms are easily converted via new mutations to resistance against any of the novel antifolates. This is a critical issue in evaluating the potential therapeutic lifetime of new drugs. The lead compounds to be tested are the five triazine antifolates WR99210, JPC-2067, JPC-2122, JPC-1058, and JPC-1054. The research will be carried out in collaboration with the Jacobus Pharmaceutical Company, a small company that is nevertheless a world leader in developing and producing antifolates against malaria and toxoplasmosis. Our collaborator, David P. Jacobus, MD has a distinguished track record of collaboration with academic researchers and open dissemination of research resources and information. The research is a unique combination of drug development and evolutionary biology with the potential to contribute to the development of new life-saving drugs while at the same time revealing new principles of protein evolution.