Okhuysen P C, Jiang X, Ye L, Johnson P C, Estes M K
Department of Internal Medicine, University of Texas-Houston Health Science Center.
J Infect Dis. 1995 Mar;171(3):566-9. doi: 10.1093/infdis/171.3.566.
Protection is not conferred by preexposure to Norwalk virus (NV). By use of an ELISA with baculovirus-expressed recombinant NV (rNV) capsid protein, the pattern of NV fecal shedding and the protective effect of rNV-specific fecal IgA (flgA) were investigated in volunteers who were repeatedly challenged with NV. After the first challenge, ill volunteers were significantly more likely than well volunteers to have NV antigen in their stool (P < .05). After challenge, antigen shedding was detected on days 1-13; ill volunteers shed the antigen longer (P = .02). A higher prechallenge rNV-specific flgA geometric mean titer was found in ill compared with well volunteers (P < .05) and in infected versus noninfected volunteers (P < .05). NV shedding was common after infection and was present up to 2 weeks after challenge. Preexisting rNV-specific flgA, like serum IgG, is not protective and may be a marker for symptomatic disease.
预先接触诺如病毒（NV）并不能提供保护。通过使用一种含有杆状病毒表达的重组NV（rNV）衣壳蛋白的酶联免疫吸附测定（ELISA），在反复接受NV攻击的志愿者中研究了NV粪便排出模式以及rNV特异性粪便免疫球蛋白A（flgA）的保护作用。在首次攻击后，患病志愿者的粪便中含有NV抗原的可能性显著高于健康志愿者（P < 0.05）。攻击后，在第1至13天检测到抗原排出；患病志愿者排出抗原的时间更长（P = 0.02）。与健康志愿者相比（P < 0.05）以及与未感染志愿者相比（P < 0.05），患病志愿者在攻击前的rNV特异性flgA几何平均滴度更高。感染后NV排出很常见，并且在攻击后长达2周都存在。预先存在的rNV特异性flgA与血清免疫球蛋白G一样，没有保护作用，可能是症状性疾病的一个标志物。
