摘要
本文利用多聚酶链式反应随机引物扩增的DNA(RAPD)多态指模技术研究其在HP菌株鉴别的应用。对47例株HP进行RAPD多态指模分析。结果发现:①40株由不同病人分离的HP菌株有不同的DNA指模;②同一菌株多次培养后其DNA指模无改变;③HP根除疗法后3个月4例、6个月1例(分离的HP菌株分与治疗前相同,提示可能是HP复发;④HP根除疗法后6个月及24个月各1例)与治疗前分离的菌株DNA指模不同,提示可能是HP再感染。结果提示RAPD多态指模技术对HP菌株的鉴别有价值。
The use of the PCR based technique of Random amplified polymorphic DNA (RAPD-PCR) fingerprinting has been reported to distinguish among clinical isolates of Helicobacter pylori based on their DNA diversity. The aims of this study were to use RAPD-PCR to identify isolates of H. pylori from different patients and patients before and after HP eradication therapy. The primer used was 10 nuleotide in length with the sequence AACGCGCAAC. Forty strains of HP isolated from clinical specimens from patients examined by gastroduoendoscopy were used to verify the specificity of the technique in distinguishing different strains of HP; the DNA fingerprinting of 7 pairs of HP strains obtained from patients before and after eradication therapy were compared using RAPD-PCR. Results: ①The DNA diversity of different isolate could easily be distinguished by RAPD-PCR fingerprinting; ②Different culture generations of the same isolate were shown to give the same RAPD-PCR fingerprint;③Four strains of HP isolated from patents 3 to 6 months after 'successful'HP eradication therapy were shown the same DNA fingerprints as those before treatment, which indicated that HP reeurrence;④One strain of HP isolated from a patient 6 months after HP eradication therapy and another strain of HP isolated from the patient 24 months after HP eradication therapy were shown the different maps of PCR-DNA fingerprinting, which indicated that these two patients were re-infected with new strains of HP. We conclude that RAPD-PCR fingerprinting is a practicable method for the identification of different strains of HP.
