Ayub Yunus, Mollel Jackson T, Mbugi Erasto V
Biochemistry Department, School of Medicine, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania.
Ministry of Health, Community Development, Gender, Elders & Children, Department of Human Resources Development, Singida Health Laboratory Assistants Training Centre, Singida, Tanzania.
East Afr Health Res J. 2018;2(1):18-25. doi: 10.24248/EAHRJ-D-17-00256. Epub 2018 Apr 1.
DNA analysis has potential for screening for and diagnosing a variety of conditions as well as the characterization of various pathogens for many purposes including to identify genetic disorders and mutations, study genetic diversity, and establish evolutional trends.
Our study compared the performance of 2 DNA extraction kits: Qiagen and prepIT•MAX. The study tested 160 formalin-fixed paraffin-embedded (FFPE) human tissue samples that had been collected at Muhimbili National Hospital (MNH) between 2010 and 2016. For each sample, DNA extraction was performed using both the Qiagen and prepIT•MAX kits followed by polymerase chain reaction (PCR) tests to target the RNA polymerase gene and gel electrophoresis.
The findings showed that the Qiagen was 3 times superior to the prepIT•MAX kit in successfully extracting mycobacterial DNA from presumptive tuberculosis (TB) FFPE tissues. Of the 160 previously Ziehl-Neelsen stain-negative suspicious tissue samples, 12 (7.5%) tested positive with the PCR. Of the 12 PCR-detected positive samples, 8 (66.7%) yielded positive results with the Qiagen kit only and 4 (33.3%) yielded positive results with both Qiagen and prepIT•MAX kits. Additionally, 10 (83.3%) came from well-formed granuloma, 1 (8%) from caseous necrosis, and 1 (8.3%) Langhans-type giant cells endorsing their potential for housing infection such as TB adenitis.
A combination of molecular techniques, microscopy, and pathological features increases detection of from FFPE tissues. Both the Qiagen and the prepIT•MAX DNA extraction kits have shown a remarkable capability for extracting DNA from , although examination of FFPE tissues is not an intended use for the prepIT MAX, according to the manufacturer. In resource-limited countries, however, these kits may complement each other. We recommend further studies for validation and optimization, which includes the cost effectiveness of prepIT•MAX extraction kit to advocate for its use in extraction of mycobacterial DNA from FFPE tissues.
DNA分析在多种疾病的筛查和诊断以及多种病原体的特征鉴定方面具有潜力，可用于多种目的，包括识别遗传疾病和突变、研究遗传多样性以及确立进化趋势。
我们的研究比较了两种DNA提取试剂盒的性能：Qiagen和prepIT•MAX。该研究检测了2010年至2016年期间在穆希姆比利国家医院（MNH）收集的160份福尔马林固定石蜡包埋（FFPE）人体组织样本。对于每个样本，使用Qiagen和prepIT•MAX试剂盒进行DNA提取，随后进行针对RNA聚合酶基因的聚合酶链反应（PCR）测试和凝胶电泳。
研究结果表明，在从疑似结核病（TB）的FFPE组织中成功提取分枝杆菌DNA方面，Qiagen试剂盒比prepIT•MAX试剂盒的效果好3倍。在160份之前齐-尼氏染色阴性的可疑组织样本中，12份（7.5%）经PCR检测呈阳性。在12份PCR检测呈阳性的样本中，8份（66.7%）仅使用Qiagen试剂盒得到阳性结果，4份（33.3%）使用Qiagen试剂盒和prepIT•MAX试剂盒均得到阳性结果。此外，10份（83.3%）来自成熟的肉芽肿，1份（8%）来自干酪样坏死，1份（8.3%）来自朗汉斯型巨细胞，这证实了它们容纳诸如结核性腺炎等感染的可能性。
分子技术、显微镜检查和病理特征相结合可提高FFPE组织中结核分枝杆菌的检测率。Qiagen和prepIT•MAX DNA提取试剂盒在从FFPE组织中提取DNA方面均显示出显著能力，不过根据制造商的说法，检查FFPE组织并非prepIT MAX试剂盒的预期用途。然而，在资源有限的国家，这些试剂盒可能会相互补充。我们建议进行进一步的研究以进行验证和优化，包括prepIT•MAX提取试剂盒的成本效益，以提倡将其用于从FFPE组织中提取分枝杆菌DNA。
