ANTIMALARIAL ACTION AND RESISTANCE

每年有2-3亿病例和2-300万人死亡，疟疾 在医学上具有压倒性的重要性。脑瘫的治疗和预防 恶性疟原虫引起的疟疾因抗药性而复杂化 氯喹(在南美洲、东南亚和非洲)，以及 缺乏明确的抗疟疾作用的分子靶点。 这些研究的具体目的是：1)定义分子(S) 负责氯喹外流，从而导致氯喹耐药性。 恶性疟原虫，2)定义氯喹的致病分子(S) 在恶性疟原虫中积累，从而对氯喹敏感， 3)建立了喹啉的构效关系 抗疟疾药。 抗氯喹恶性疟原虫与敏感恶性疟原虫的杂交 将被用来确定负责的基因(S) 对氯喹耐药。为了做到这一点，来自于 抗性的DD2亲本菌株将与来自 抗性后代。根据这一信息，多肽将被 合成并用于产生抗体以检测基因产物 在耐药和敏感品系中。负责的分子(S) 氯喹的蓄积将通过其结合能力来确定 氯喹的用途：凝胶电泳法和放射自显影，氯喹-- 琼脂糖柱层析，抑制氯喹蓄积 通过对重组囊泡制剂的抗体，以及 光活化交联剂。发展结构性活动 连接关系，具有特定结构的喹啉类似物 将测试其抑制氯喹的能力。 重组囊泡制剂的蓄积和 氯喹敏感和耐药的抗疟原虫活性 菌株。 这些研究的广泛的长期目标是提供一个合理的 抗疟疾药物的开发基础 耐多重恶性疟原虫。

With 200-300 million cases and 2-3 million deaths each year, malaria is of overwhelming medical importance. The treatment and prevention of malaria due to Plasmodium falciparum is complicated by resistance to chloroquine (in South America, Southeast Asia and Africa), and by the absence of defined molecular targets for antimalarial action. The specific aims of these studies are to: 1) define the molecule(s) responsible for chloroquine efflux and thus for chloroquine resistance in P. falciparum, 2) define the molecule(s) responsible for chloroquine accumulation and thus for susceptibility to chloroquine in P. falciparum, and 3) develop structure-activity relationships for the quinoline antimalarials. A cross between chloroquine-resistant and susceptible P. falciparum will be used to identify the gene(s) responsible for chloroquine-resistance. To accomplish this, a genomic DNA library from the resistant Dd2 parent strain will be hybridized to DNA from the resistant progeny. Based on this information peptides will be synthesized and used to produce antibodies to test for the gene product in resistant and susceptible strains. The molecule(s) responsible for chloroquine accumulation will be identified by its ability to bind chloroquine using: gel electrophoresis and autoradiography, chloroquine-- sepharose column chromatography, inhibition of chloroquine accumulation by antibodies to a reconstituted vesicle preparation, and photoactivatable cross-linking reagents. To develop structure-activity linking relationships, quinoline analogs with specific structural modifications will be tested for their ability to inhibit chloroquine accumulation by the reconstituted vesicle preparation and for antiplasmodial activity against chloroquine-susceptible and resistant strains. The broad long-term goal of these studies is to provide a rational basis for the development of antimalarials active against multiply-resistant P. falciparum.