Bansal Devendra, Sehgal Rakesh, Chawla Yogesh, Malla Nancy, Mahajan R C
Department of Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh, India.
Indian J Med Res. 2006 Aug;124(2):189-94.
BACKGROUND & OBJECTIVES: Amoebiasis, caused by Entamoeba sp. a protozoan parasite, is a major public health problem in tropical and subtropical countries. The symptomatic patients are treated by specific chemotherapy. However, there are reports of treatment failure in some cases suggesting the possibility of drug resistance. The present study was therefore planned to assess the presence and expression of mRNA of multidrug resistance (MDR) gene in clinical isolates of Entamoeba histolytica and E. dispar.
Forty five clinical isolates of Entamoeba sp. [E. histolytica (15) and E. dispar (30)] were maintained in polyxenic followed by monoxenic medium. DNA and total RNA were extracted from clinical isolates of Entamoeba sp. and from sensitive strain of E. histolytica (HM1: IMSS) and subjected to polymerase chain reaction (PCR) and multiplex reverse transcription (RT)-PCR techniques.
The 344 bp segment of E. histolytica DNA was seen by PCR using primers specific to EhPgp1 in all clinical isolates and sensitive strain of E. histolytica. Over expression of EhPgp1 was observed only in resistant mutant of E. histolytica; however, transcription of EhPgp1 was not seen in any clinical isolates and sensitive strain of E. histolytica.
INTERPRETATION & CONCLUSION: The findings of the present study indicate that, so far, drug resistance in clinical isolates of E. histolytica does not seem to be a major problem in this country. However, susceptibility of clinical isolates of E. histolytica against various antiamoebic drugs needs to be investigated for better management.
由原生动物寄生虫溶组织内阿米巴引起的阿米巴病是热带和亚热带国家的一个主要公共卫生问题。有症状的患者通过特异性化疗进行治疗。然而，有报道称在某些病例中治疗失败，提示存在耐药的可能性。因此，本研究旨在评估溶组织内阿米巴和迪斯帕内阿米巴临床分离株中多药耐药（MDR）基因mRNA的存在及表达情况。
45株阿米巴临床分离株[溶组织内阿米巴（15株）和迪斯帕内阿米巴（30株）]先在多菌培养基中培养，随后转至单菌培养基中培养。从阿米巴临床分离株以及溶组织内阿米巴敏感株（HM1:IMSS）中提取DNA和总RNA，并进行聚合酶链反应（PCR）和多重逆转录（RT）-PCR技术检测。
使用针对EhPgp1的特异性引物通过PCR在所有溶组织内阿米巴临床分离株和敏感株中均可见344 bp的溶组织内阿米巴DNA片段。仅在溶组织内阿米巴耐药突变株中观察到EhPgp1的过表达；然而，在任何溶组织内阿米巴临床分离株和敏感株中均未见到EhPgp1的转录。
本研究结果表明，到目前为止，溶组织内阿米巴临床分离株中的耐药性在该国似乎不是一个主要问题。然而，为了更好地进行管理，需要对溶组织内阿米巴临床分离株对各种抗阿米巴药物的敏感性进行研究。
