Department of Microbiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Viral Immunol. 2010 Jun;23(3):329-34. doi: 10.1089/vim.2009.0082.
Archival serum samples from elderly individuals with underlying chronic obstructive pulmonary disease (COPD) who were enrolled in a double-blind case-control study of seasonal influenza vaccine efficacy were assayed for cross-neutralizing antibody formation to avian influenza A (H5N1) virus. Of 118 serum samples, 58 were collected from influenza vaccinees (mean age 68.5 y), and 60 from placebo controls (mean age 68.4 y) who received vitamin B injections. Blood samples were collected before and at 1 mo after seasonal influenza vaccination from all subjects; in addition, for a longitudinal follow-up period of 1 y paired-blood samples were collected again from subjects who developed acute respiratory illness. Hemagglutination inhibition assay for antibodies to influenza A (H1N1), influenza A (H3N2), and influenza B viruses was carried out to determine the serological response to vaccination, and to diagnose influenza viral infection, while microneutralization assays were performed to detect cross-reactive antibody to H5N1 virus. Pre-existing cross-reactive H5N1 antibody at reciprocal titer 10 was found in 6 (10.3%) vaccinees and 4 (6.7%) placebo controls. There was no change in H5N1 antibody titer in these subjects after vaccination. On the other hand, 3 (5.2%) vaccinees developed seroconversion to H5N1 virus at 1 mo after vaccination, even though they had no pre-existing H5N1 antibody in their first blood samples. No cross-neutralizing antibody to H5N1 virus was detected in the placebo controls or in the 22 influenza patients, suggesting that influenza vaccination, but not influenza virus infection, induces cross-neutralizing antibody against avian influenza H5N1 virus.
从患有潜在慢性阻塞性肺疾病（COPD）的老年个体中采集存档的血清样本，这些个体参加了季节性流感疫苗功效的双盲病例对照研究，用于检测针对甲型流感（H5N1）病毒的交叉中和抗体形成。在 118 份血清样本中，有 58 份来自流感疫苗接种者（平均年龄 68.5 岁），60 份来自接受维生素 B 注射的安慰剂对照者（平均年龄 68.4 岁）。所有受试者在接种季节性流感疫苗前和接种后 1 个月采集血液样本；此外，对于 1 年的纵向随访期，从发生急性呼吸道疾病的受试者中再次采集配对的血液样本。进行血凝抑制试验以检测针对甲型流感（H1N1）、甲型流感（H3N2）和乙型流感病毒的抗体，以确定疫苗接种的血清学反应，并诊断流感病毒感染，同时进行微量中和试验以检测对 H5N1 病毒的交叉反应性抗体。在 6 名（10.3%）疫苗接种者和 4 名（6.7%）安慰剂对照者中发现了 H5N1 抗体的交叉反应性抗体，其滴度为 10。这些受试者在接种疫苗后 H5N1 抗体滴度没有变化。另一方面，3 名（5.2%）疫苗接种者在接种疫苗后 1 个月发生了 H5N1 病毒血清转化，尽管他们在第一次血液样本中没有预先存在的 H5N1 抗体。在安慰剂对照者或 22 名流感患者中均未检测到针对 H5N1 病毒的交叉中和抗体，这表明流感疫苗接种而不是流感病毒感染可诱导针对甲型流感 H5N1 病毒的交叉中和抗体。
