Safety and immunogenicity of Escherichia coli O157O-specific polysaccharide conjugate vaccine in 2-5-year-old children
Safety and immunogenicity of Escherichia coli O157O-specific polysaccharide conjugate vaccine in 2-5-year-old children
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DOI：
10.1086/499821
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发表时间：
2006-02-15
影响因子：
6.4
通讯作者：
Szu, SC
中科院分区：
文献类型：
--
作者：
Ahmed, A;Li, JP;Szu, SC
背景大肠杆菌O 157：H7引起严重的肠炎和溶血性尿毒症综合征，主要发生在幼儿和老年人中。与志贺氏菌相似，血清中抗E.大肠杆菌O 157：H7可以通过在肠道中溶解接种物来赋予免疫力。在成人中进行的一期试验表明，E.大肠杆菌O 157：H7 O特异性多糖结合重组铜绿假单胞菌外毒素A（O 157-rEPA）安全、免疫原性好。O 157-rEPA疫苗的2期试验在49名2 - 5岁儿童中进行，这些儿童被随机分为接受1剂或2剂疫苗的组。监测不良反应。检测血清IgG脂多糖（LPS）抗体。未见明显不良反应。在第一次给药后1周，大多数儿童（81%）的血清IgG LPS抗体增加了14倍。在第一次给药后6周，所有儿童的反应都增加了18倍;第二次给药没有引起加强反应。在第一次接种后26周，血清IgG LPS抗体的几何平均滴度与接种前滴度相似，比接种前滴度高20倍。这些血清样品具有高滴度的杀菌活性，其与血清IgG LPS抗体滴度大致相关（r = 0.78）。O 157-rEPA疫苗在幼儿中是安全和免疫原性的。计划在婴儿中同时进行该结合疫苗与常规免疫接种的III期试验。
Background. Escherichia coli O157:H7 causes severe enteritis and hemolytic-uremic syndrome, mostly in young children and older adults. Similar to the case with Shigella, serum IgG against the O-specific polysaccharide of E. coli O157: H7 may confer immunity by lysing the inoculum in the intestine. A phase 1 trial in adults showed that a vaccine of E. coli O157: H7 O-specific polysaccharide conjugated to recombinant exotoxin A of Pseudomonas aeruginosa ( O157-rEPA) was safe and immunogenic.Methods. A phase 2 trial of the O157-rEPA vaccine was conducted in 49 children 2 - 5 years old who were divided randomly into groups receiving 1 or 2 doses of vaccine. Adverse reactions were monitored. Serum IgG lipopolysaccharide ( LPS) antibodies were determined.Results. No significant adverse reactions were observed. At 1 week after the first dose was administered, most children ( 81%) responded with a 14-fold increase in serum IgG LPS antibodies. At 6 weeks after the first dose was administered, all children responded with a 18- fold increase; a second dose did not elicit a booster response. At 26 weeks after the first dose was administered, the geometric mean titer of serum IgG LPS antibodies was similar to 20-fold higher than was the prevaccination titer. These serum samples had high titers of bactericidal activity that were correlated roughly with serum IgG LPS antibody titers (r = .78).Conclusions. The O157-rEPA vaccine was safe and immunogenic in young children. A phase 3 trial of the administration of this conjugate vaccine concurrently with routine immunization in infants is planned.