Tirasophon W, Rajkulchai P, Ponglikitmongkol M, Wilairat P, Boonsaeng V, Panyim S
Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand.
Am J Trop Med Hyg. 1994 Sep;51(3):308-13. doi: 10.4269/ajtmh.1994.51.308.
A highly sensitive, rapid and simple method to detect human malaria in blood samples was developed. Malaria parasite DNA in blood from a fingerprick was directly amplified by the polymerase chain reaction (PCR) using two sets of primers to yield a 206-basepair (bp) product for Plasmodium falciparum and a 183-bp product for P. vivax. Both were easily visualized in an ethidium bromide-stained agarose gel, allowing identification of the two human malaria species in a single amplification reaction. As little as a one P. falciparum and/or P. vivax parasite per microliter of blood was detectable by this method, a sensitivity superior to that of thick blood film microscopy. The total time required for diagnosis of 48 blood samples, starting from fingerprick blood collection, was approximately 4 hr. When compared with microscopic examination by an expert microscopist, results showed a sensitivity of 89% for P. falciparum and 91% for P. vivax and an overall specificity of 94%. Six infected blood samples classified by microscopy as single species were diagnosed by the PCR method as being mixed P. falciparum and P. vivax infections. The high sensitivity, rapidity, and simplicity of the method should make it attractive for a large-scale epidemiology study, follow-up of drug treatment, and immunization trials.
开发了一种用于检测血样中人类疟疾的高灵敏度、快速且简便的方法。使用两组引物通过聚合酶链反应（PCR）直接扩增来自指尖采血的血液中的疟原虫DNA，以产生针对恶性疟原虫的206碱基对（bp）产物和针对间日疟原虫的183 bp产物。两者在溴化乙锭染色的琼脂糖凝胶中都易于观察到，从而能够在单次扩增反应中鉴定出两种人类疟原虫。通过该方法可检测到低至每微升血液中有一个恶性疟原虫和/或间日疟原虫寄生虫，其灵敏度优于厚血膜显微镜检查。从指尖采血开始，诊断48份血样所需的总时间约为4小时。与专业显微镜检查人员的显微镜检查相比，结果显示对恶性疟原虫的灵敏度为89%，对间日疟原虫的灵敏度为91%，总体特异性为94%。显微镜检查分类为单一物种的6份感染血样经PCR方法诊断为恶性疟原虫和间日疟原虫混合感染。该方法的高灵敏度、快速性和简便性使其对大规模流行病学研究、药物治疗随访和免疫试验具有吸引力。
