Freitas-Lidani Kárita Cláudia, Messias-Reason Iara J de, Ishikawa Edna Aoba Y
Laboratório de Imunopatologia Molecular, Departamento de Patologia Médica, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brasil.
Núcleo de Medicina Tropical, Universidade Federal do Pará, Belém, PA, Brasil.
Mem Inst Oswaldo Cruz. 2014 Jul;109(4):442-7. doi: 10.1590/0074-0276130285. Epub 2014 Jul 3.
The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.
本研究的目的是通过使用三组引物，检测在巴西帕拉州巴尔卡雷纳捕获的长须罗蛉体内婴儿利什曼原虫（利什曼原虫属）的自然感染情况。采用这种方法，无需事先解剖白蛉标本。从280只长须罗蛉雌性标本的整个虫体中提取DNA。使用针对利什曼原虫动质体小环DNA（kDNA）、小外显子基因和小亚基核糖体RNA（SSU-rRNA）基因的PCR引物，分别产生400 bp、780 bp和603 bp的片段。使用kDNA引物时，在8.6%的病例中发现寄生虫感染；使用小外显子基因引物时，在7.1%的病例中发现感染；使用SSU-rRNA基因引物时，在5.3%的病例中发现感染。这些数据表明，聚合酶链反应作为一种工具，通过估计流行地区疾病传播的风险来调查内脏利什曼病的分子流行病学具有重要意义，其中kDNA引物是寄生虫最可靠的标记。
