Department of Infection Biology and National Centre for Zoonosis Research, Institute for Infection and Global Health, University of Liverpool, Leahurst Campus, Neston, UK.
J Appl Microbiol. 2011 Dec;111(6):1505-14. doi: 10.1111/j.1365-2672.2011.05152.x. Epub 2011 Oct 6.
To characterize 12 Salmonella Virchow isolates from human and avian sources to begin to determine the genetic relationships within the serovar, determine its capacity to invade and induce inflammatory responses in human intestinal epithelial cells and investigate its ability to colonize the chicken gastrointestinal tract.
Multi-Locus Sequence Typing (MLST) revealed that 11 isolates belonged to sequence type 16 (ST16). Pulsed Field Gel Electrophoresis (PFGE) grouped the isolates into two main clusters. All isolates contained genes associated with virulence determined through PCR virulotyping. All the S. Virchow isolates had the ability to invade human epithelial cells and elicit high levels of production of the pro-inflammatory chemokine interleukin-8 (IL-8). Experimental infection of poultry showed S. Virchow colonizes the caeca and spleen.
Isolates within the serovar show high levels of genetic relatedness regardless of the source. The data indicates S. Virchow is an invasive and inflammatory serovar, consistent with its association with invasive salmonellosis in humans.
The poultry infection experiment included in this study shows S. Virchow can colonize the gastrointestinal tract rapidly and to high levels with the chickens showing no clinical signs of infection. The asymptomatic colonization of chickens indicates an increased ability of S. Virchow to enter the food chain undetected and cause human salmonellosis which because of the invasive and inflammatory nature of S. Virchow seen during the Caco2 invasion assay and previous studies showing its invasive nature in humans and increasing resistance to antibiotics is a public health concern.
对来自人和禽类来源的 12 株沙门氏菌 Virchow 分离株进行特征分析，以确定血清型内的遗传关系，确定其侵袭能力和诱导人肠上皮细胞炎症反应的能力，并研究其在鸡胃肠道定殖的能力。
多位点序列分型（MLST）显示 11 株分离株属于序列型 16（ST16）。脉冲场凝胶电泳（PFGE）将分离株分为两个主要簇。所有分离株均含有通过 PCR 毒力定型确定的与毒力相关的基因。所有 S. Virchow 分离株均具有侵袭人上皮细胞并引发高水平促炎趋化因子白细胞介素-8（IL-8）产生的能力。禽类的实验感染表明，S. Virchow 定植于盲肠和脾脏。
无论来源如何，血清型内的分离株显示出高度的遗传相关性。数据表明，S. Virchow 是一种侵袭性和炎症性血清型，与其在人类侵袭性沙门氏菌病的关联一致。
本研究中包括的禽类感染实验表明，S. Virchow 可以迅速定植于家禽的胃肠道并达到高水平，而家禽没有感染的临床症状。鸡的无症状定植表明，S. Virchow 具有更高的能力进入食物链而不被察觉，并导致人类沙门氏菌病，这是因为在 Caco2 侵袭试验和先前的研究中观察到 S. Virchow 的侵袭性和炎症性，以及其在人类中的侵袭性和对抗生素的耐药性增加，这是一个公共卫生问题。
