Gustavsson Anders, Unemo Magnus, Blomberg Björn, Danielsson Dan
Department of Medicine, Division of Gastroenterology, Orebro University Hospital, Orebro, Sweden.
Dig Dis Sci. 2005 Feb;50(2):375-80. doi: 10.1007/s10620-005-1613-1.
The cagA gene, alleles of the vacA gene,random amplified polymorphic DNA (RAPD), and neutrophil activating capacity (HpNAC) were used to examine paired H. pylori isolates from 10 noneradicated individuals 9 years apart. Paired isolates from each patient were indistinguishable with regard to vacA alleles, RAPD, and HpNAC. Isolates from nine patients showed concordance for the cagA gene, which was not detected in the recent isolate of the tenth patient. Antibodies to CagA were, however, demonstrated in the serum specimens 9 years apart and were also present in two other patients whose paired isolates were cagA-, indicating the existence of both cagA+ and cagA-organisms, with the latter predominating in some patients. The present study suggests a greater stability of phenotypic and genotypic markers of H. pylori than previously regarded. This might be true for a community with low infection and transmission rates. Complementary techniques like microarrays might, however, disclose evolutionary changes not identified here.
采用细胞毒素相关基因A（cagA）、空泡毒素A（vacA）基因的等位基因、随机扩增多态性DNA（RAPD）以及中性粒细胞激活能力（HpNAC），对10名未根除幽门螺杆菌的个体在相隔9年时间采集的配对菌株进行检测。每位患者的配对菌株在vacA等位基因、RAPD和HpNAC方面无法区分。9名患者的菌株在cagA基因方面表现一致，但在第10名患者最近分离出的菌株中未检测到该基因。然而，相隔9年的血清标本中均检测到了抗CagA抗体，并且在另外两名配对菌株为cagA阴性的患者血清中也存在该抗体，这表明同时存在cagA阳性和cagA阴性菌株，且在部分患者中后者占主导。本研究提示，幽门螺杆菌的表型和基因型标记比之前认为的具有更高的稳定性。在感染和传播率较低的群体中可能确实如此。然而，像微阵列这样的补充技术可能会揭示此处未发现的进化变化。
