DEVELOPMENT OF RECOMBINANT BCG-VP8 VACCINES

Rotavizuses是婴幼儿严重腹泻的主要原因 发达国家和发展中国家的儿童。 两个外衣壳 轮状病毒蛋白VP 7和VP 4与诱导 中和抗体已经在实验动物中显示， 与抵抗疾病有关。 血清型特异性为 主要与VP 7有关。 然而，最近的研究表明， 出现的人轮状病毒VP 4的抗原关系 比VP 7的多态性更低。 人轮状病毒株， 与症状性感染相关，并表现出VP 7特异性 血清型1、2、3、4或9各自具有相似的VP 4， 中和试验 本研究的目的是：（i）使用VP 8 构建BCG-VP 8重组体，并评价其表达能力 诱导轮状病毒特异性中和抗体 动物，以及（ii）利用由此获得的信息， 开发用于口服给药的人轮状病毒疫苗。 代表轮状病毒外壳蛋白VP 8亚基的cDNA 将来自人轮状病毒KU株的VP 4克隆到三种不同的BCG中， 向量。 在这些系统中表达的VP 8亚基被识别， 通过超免疫抗血清中存在的抗体进行免疫印迹试验，以： (i)人轮状病毒株Wa，（ii）表达的KU-VP 4，和（iii） 表达了VP 4的切割亚基KU-VP 8。 这些观察结果表明 VP 8亚基以抗原正确的形式表达， 重组体为真正的VP 8。

Rotavizuses are the major cause of severe diarrhea in infants and young children in both developed and developing countries. Two outer capsid rotavirus proteins, VP7 and VP4, are associated with the induction of neutralizing antibodies which have been shown in experimental animals to be associated with resistance to illness. Serotype specificity is associated primarily with VP7. However, recent studies have elucidated the antigenic relationships of the VP4 of human rotaviruses which appear to be less polymorphic than VP7. Human rotavirus strains that are associated with symptomatic infection and that exhibit VP7 specificity of serotype 1, 2, 3, 4 or 9 each possess a similar VP4 as determined by neutralization assay. Objectives of this study were: (i) to use the VP8 subunit of VP4 to develop a BCG-VP8 recombinant and evaluate its ability to induce specific rotavirus neutralizing antibodies in experimental animals, and (ii) to utilize the information thus obtained for the development of a human rotavirus vaccine for oral administration. The cDNA representing the VP8 subunit of outer capsid rotavirus protein VP4 from the human rotavirus KU strain was cloned in three different BCG vectors. The VP8 subunit expressed in these systems was recognized in an immunoblot assay by antibodies present in hyperimmune antiserum to: (i) human rotavirus strain Wa, (ii) expressed KU-VP4, and (iii) expressed KU-VP8, a cleavage subunit of VP4. These observations suggest that the VP8 subunit was expressed in an antigenically correct form by the recombinant as authentic VP8.