Smiley Kristi L, McNeal Monica M, Basu Mitali, Choi Anthony H-C, Clements John D, Ward Richard L
Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229, and Tulane University Medical Center, New Orleans, LA 70112, USA.
J Virol. 2007 Apr;81(8):3740-8. doi: 10.1128/JVI.01877-06. Epub 2007 Jan 24.
Mucosal immunization of mice with chimeric, Escherichia coli-expressed VP6, the protein that comprises the intermediate capsid layer of the rotavirus particle, together with attenuated E. coli heat-labile toxin LT(R192G) as an adjuvant, reduces fecal shedding of rotavirus antigen by >95% after murine rotavirus challenge, and the only lymphocytes required for protection are CD4+ T cells. Because these cells produce cytokines with antiviral properties, the cytokines whose expression is upregulated in intestinal memory CD4+ T cells immediately after rotavirus challenge of VP6/LT(R192G)-immunized mice may be directly or indirectly responsible for the rapid suppression of rotavirus shedding. This study was designed to identify which cytokines are significantly upregulated in intestinal effector sites and secondary lymphoid tissues of intranasally immunized BALB/c mice after challenge with murine rotavirus strain EDIM. Initially, this was done by using microarray analysis to quantify mRNAs for 96 murine common cytokines. With this procedure, the synthesis of mRNAs for gamma interferon (IFN-gamma) and interleukin-17 (IL-17) was found to be temporarily upregulated in intestinal lymphoid cells of VP6/LT(R192G)-immunized mice at 12 h after rotavirus challenge. These cytokines were also produced in CD4+ T cells obtained from intestinal sites specific to VP6/LT(R192G)-immunized mice after in vitro exposure to VP6 as determined by intracellular cytokine staining and secretion of cytokines. Although genetically modified mice that lack receptors for either IFN-gamma or IL-17 remained protected after immunization, these results provide suggestive evidence that these cytokines may play direct or indirect roles in protection against rotavirus after mucosal immunization of mice with VP6/LT(R192G).
用嵌合的、大肠杆菌表达的VP6(轮状病毒颗粒中间衣壳层的组成蛋白)对小鼠进行黏膜免疫,同时将减毒的大肠杆菌不耐热毒素LT(R192G)作为佐剂,在小鼠受到轮状病毒攻击后,可使轮状病毒抗原的粪便排出量减少>95%,且保护所需的唯一淋巴细胞是CD4+ T细胞。由于这些细胞产生具有抗病毒特性的细胞因子,在VP6/LT(R192G)免疫的小鼠受到轮状病毒攻击后,肠道记忆CD4+ T细胞中立即上调表达的细胞因子可能直接或间接导致轮状病毒排出的快速抑制。本研究旨在确定在用鼠轮状病毒株EDIM攻击后,经鼻免疫的BALB/c小鼠的肠道效应部位和二级淋巴组织中哪些细胞因子显著上调。最初,通过使用微阵列分析对96种小鼠常见细胞因子的mRNA进行定量来完成此项研究。通过该程序,发现在轮状病毒攻击后12小时,VP6/LT(R192G)免疫的小鼠肠道淋巴细胞中γ干扰素(IFN-γ)和白细胞介素-17(IL-17)的mRNA合成暂时上调。通过细胞内细胞因子染色和细胞因子分泌测定,在体外暴露于VP6后,从VP6/LT(R192G)免疫小鼠的肠道部位获得的CD4+ T细胞中也产生了这些细胞因子。尽管缺乏IFN-γ或IL-17受体的基因改造小鼠在免疫后仍受到保护,但这些结果提供了提示性证据,表明这些细胞因子在用VP6/LT(R192G)对小鼠进行黏膜免疫后,可能在抵抗轮状病毒的保护中发挥直接或间接作用。