Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney ce...Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney cells (Vero), human kidney carcinoma cells (Ketr-3) and bladder carcinoma cells (EJ) were infected by UPEC132, a clinical strain isolated from Tianjin, China, and were compared for their capacities to allow the adherence and invasion by this strain. The results revealed that all these cell lines could be attached and invaded by UPEC132. The adherence rates for Vero, Ketr-3 and EJ cells were (49.20 ± 7.55)%, (55.22 ± 4.09)% and (73.20 ± 5.26)%, respectively, and invasion frequencies were (2.61 ± 0.32)×10-3, (3.00 ± 0.34)×10-3 and (3.25 ± 0.20)×10-3, respectively. The statistical analysis showed that the adherence rate for EJ cells was significantly higher than those for the other two cell lines (P<0.05), and the invasion frequencies for EJ and Ketr-3 cells had no statistical differences (P>0.05) but were higher than that for Vero cells (P<0.05). Three cell lines were detected for the receptors for P pili of UPEC by using indirect immunofluorescence. The results showed that receptors existed on the surfaces of all cell lines, and the highest distribution was found on the surface of EJ cells. Additionally, the invasion of EJ cells by recombinant UPEC132/pSELECT-GFP could be directly visualized using confocal microscopy. These data strongly implicated that EJ cells could be more easily infected by UPEC132 than the other cells, and thus could serve as a good experimental target for further investigation of UPEC infection.展开更多
猪链球菌2型(Streptococcus suis serotype2,SS2)是一种世界范围内的引起猪链球菌病的重要的人兽共患病原菌,人感染SS2后多呈现败血症型和脑膜炎型。2005年猪链球菌在我国四川省的感染暴发和近年来不断出现的零散病例给我国的公共卫生...猪链球菌2型(Streptococcus suis serotype2,SS2)是一种世界范围内的引起猪链球菌病的重要的人兽共患病原菌,人感染SS2后多呈现败血症型和脑膜炎型。2005年猪链球菌在我国四川省的感染暴发和近年来不断出现的零散病例给我国的公共卫生和食品安全带来了威胁,但迄今为止,对SS2致病机制研究尚不够深入。SS2的致病过程和宿主细胞相互作用密切相关,SS2-体外宿主细胞相互作用模型的建立对于揭示SS2致病分子机理具有重要的意义。目前的研究报道主要是从猪链球菌黏附与侵袭上皮细胞或内皮细胞、猪链球菌抗吞噬细胞的吞噬和猪链球菌激活免疫细胞炎症反应方面研究猪链球菌与宿主细胞的相互作用,但与其他常致病性链球菌如化脓性链球菌和肺炎链球菌相比,有些SS2-体外宿主细胞相互作用模型还缺乏统一的标准,由于感染模型的实验参数不尽相同得到结果也有所不同。本文对近年来猪链球菌2型与宿主细胞体外相互作用及其致病机理研究进展作一综述。展开更多
AIM： To assess the adhesion and invasion abilities of different mouse adapted H py/or/strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA. METHODS： The adher...AIM： To assess the adhesion and invasion abilities of different mouse adapted H py/or/strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA. METHODS： The adherence and invasion abilities of different N pylori strains in different epithelial cell lines were examined by the gentamycin protection assay. The null mutants of cagA and vacA were processed by direct PCR mutation method. The morphologic changes of different cell lines after N pylori attachment were examined by microscopy. RESULTS： The densities of adherence to and invasion into cells in vitro were different from those in the mouse infection experiments. 88-3887 strain could invade and adhere to cells stronger than SS1 and X47. All tested strains had better adhering and invasive abilities in SCG-7901 cell. CagA and vacA minus mutants had the same invasion and adherent abilities as their wild types. In all strains and cell lines tested, only AGS cell had the significant hummingbird phenotype after inoculation with the 88-3887 wild-type. CONCLUSION： Both the host cells and the bacteria play important parts in the invasion and adhesion abilities of Hpylori. CagA and VacA are not related to the ability of invasion and adhesion of Hpylori in different cell lines in vitro.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 30470096)Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20070062010)
文摘Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney cells (Vero), human kidney carcinoma cells (Ketr-3) and bladder carcinoma cells (EJ) were infected by UPEC132, a clinical strain isolated from Tianjin, China, and were compared for their capacities to allow the adherence and invasion by this strain. The results revealed that all these cell lines could be attached and invaded by UPEC132. The adherence rates for Vero, Ketr-3 and EJ cells were (49.20 ± 7.55)%, (55.22 ± 4.09)% and (73.20 ± 5.26)%, respectively, and invasion frequencies were (2.61 ± 0.32)×10-3, (3.00 ± 0.34)×10-3 and (3.25 ± 0.20)×10-3, respectively. The statistical analysis showed that the adherence rate for EJ cells was significantly higher than those for the other two cell lines (P<0.05), and the invasion frequencies for EJ and Ketr-3 cells had no statistical differences (P>0.05) but were higher than that for Vero cells (P<0.05). Three cell lines were detected for the receptors for P pili of UPEC by using indirect immunofluorescence. The results showed that receptors existed on the surfaces of all cell lines, and the highest distribution was found on the surface of EJ cells. Additionally, the invasion of EJ cells by recombinant UPEC132/pSELECT-GFP could be directly visualized using confocal microscopy. These data strongly implicated that EJ cells could be more easily infected by UPEC132 than the other cells, and thus could serve as a good experimental target for further investigation of UPEC infection.
文摘猪链球菌2型(Streptococcus suis serotype2,SS2)是一种世界范围内的引起猪链球菌病的重要的人兽共患病原菌,人感染SS2后多呈现败血症型和脑膜炎型。2005年猪链球菌在我国四川省的感染暴发和近年来不断出现的零散病例给我国的公共卫生和食品安全带来了威胁,但迄今为止,对SS2致病机制研究尚不够深入。SS2的致病过程和宿主细胞相互作用密切相关,SS2-体外宿主细胞相互作用模型的建立对于揭示SS2致病分子机理具有重要的意义。目前的研究报道主要是从猪链球菌黏附与侵袭上皮细胞或内皮细胞、猪链球菌抗吞噬细胞的吞噬和猪链球菌激活免疫细胞炎症反应方面研究猪链球菌与宿主细胞的相互作用,但与其他常致病性链球菌如化脓性链球菌和肺炎链球菌相比,有些SS2-体外宿主细胞相互作用模型还缺乏统一的标准,由于感染模型的实验参数不尽相同得到结果也有所不同。本文对近年来猪链球菌2型与宿主细胞体外相互作用及其致病机理研究进展作一综述。
基金the National Natural Science Foundation of China,No.30370078
文摘AIM： To assess the adhesion and invasion abilities of different mouse adapted H py/or/strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA. METHODS： The adherence and invasion abilities of different N pylori strains in different epithelial cell lines were examined by the gentamycin protection assay. The null mutants of cagA and vacA were processed by direct PCR mutation method. The morphologic changes of different cell lines after N pylori attachment were examined by microscopy. RESULTS： The densities of adherence to and invasion into cells in vitro were different from those in the mouse infection experiments. 88-3887 strain could invade and adhere to cells stronger than SS1 and X47. All tested strains had better adhering and invasive abilities in SCG-7901 cell. CagA and vacA minus mutants had the same invasion and adherent abilities as their wild types. In all strains and cell lines tested, only AGS cell had the significant hummingbird phenotype after inoculation with the 88-3887 wild-type. CONCLUSION： Both the host cells and the bacteria play important parts in the invasion and adhesion abilities of Hpylori. CagA and VacA are not related to the ability of invasion and adhesion of Hpylori in different cell lines in vitro.
