Microbial Pathogenesis and Vaccine Biotechnology Laboratory, Department of Molecular Genetics and Microbiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Alameda 340, Santiago 651-3492, Chile.
World J Gastroenterol. 2010 Jan 21;16(3):320-9. doi: 10.3748/wjg.v16.i3.320.
To evaluate how widely Helicobacter pylori (H. pylori) HopE and HopV porins are expressed among Chilean isolates and how seroprevalent they are among infected patients in Chile.
H. pylori hopE and hopV genes derived from strain CHCTX-1 were cloned by polymerase chain reaction (PCR), sequenced and expressed in Escherichia coli AD494 (DE3). Gel-purified porins were used to prepare polyclonal antibodies. The presence of both genes was tested by PCR in a collection of H. pylori clinical isolates and their expression was detected in lysates by immunoblotting. Immune responses against HopE, HopV and other H. pylori antigens in sera from infected and non-infected patients were tested by Western blotting using these sera as first antibody on recombinant H. pylori antigens.
PCR and Western blotting assays revealed that 60 and 82 out of 130 Chilean isolates carried hopE and hopV genes, respectively, but only 16 and 9, respectively, expressed these porins. IgG serum immunoreactivity evaluation of 69 H. pylori-infected patients revealed that HopE and HopV were infrequently recognized (8.7% and 10.1% respectively) compared to H. pylori VacA (68.1%) and CagA (59.5%) antigens. Similar values were detected for IgA serum immunoreactivity against HopE (11.6%) and HopV (10.5%) although lower values for VacA (42%) and CagA (17.4%) were obtained when compared to the IgG response.
A scarce expression of HopE and HopV among Chilean isolates was found, in agreement with the infrequent seroconversion against these antigens when tested in infected Chilean patients.
评估幽门螺杆菌（H. pylori）HopE 和 HopV 孔蛋白在智利分离株中的广泛表达情况，以及它们在智利感染患者中的血清流行率。
通过聚合酶链反应（PCR）从菌株 CHCTX-1 中克隆 H. pylori hopE 和 hopV 基因，测序并在大肠杆菌 AD494（DE3）中表达。凝胶纯化的孔蛋白用于制备多克隆抗体。通过 PCR 测试了一组 H. pylori 临床分离株中这两个基因的存在，并通过免疫印迹检测了裂解物中的表达。使用这些血清作为重组 H. pylori 抗原的第一抗体，通过 Western blot 检测感染和未感染患者血清中针对 HopE、HopV 和其他 H. pylori 抗原的免疫反应。
PCR 和 Western blot 检测显示，130 株智利分离株中有 60 株和 82 株分别携带 hopE 和 hopV 基因，但只有 16 株和 9 株分别表达这些孔蛋白。对 69 例 H. pylori 感染患者的 IgG 血清免疫反应性评估显示，与 H. pylori VacA（68.1%）和 CagA（59.5%）抗原相比，HopE 和 HopV 的识别频率较低（分别为 8.7%和 10.1%）。针对 HopE（11.6%）和 HopV（10.5%）的 IgA 血清免疫反应性也检测到类似的值，尽管与 IgG 反应相比，VacA（42%）和 CagA（17.4%）的值较低。
在智利分离株中发现 HopE 和 HopV 的表达较少，这与在智利感染患者中针对这些抗原的血清转化率较低一致。
