Stable Chromosomal Expression of Shigella flexneri 2a and 3a O-Antigens in the Live Salmonella Oral Vaccine Vector Ty21a
Stable Chromosomal Expression of Shigella flexneri 2a and 3a O-Antigens in the Live Salmonella Oral Vaccine Vector Ty21a
复制标题
DOI：
10.1128/cvi.00181-17
复制
发表时间：
2017-12-01
影响因子：
--
通讯作者：
Kopecko, Dennis J.
中科院分区：
文献类型：
--
作者：
Dharmasena, Madushini N.;Osorio, Manuel;Kopecko, Dennis J.
我们一直在探索使用减毒活沙门氏菌伤寒血清型Ty21a疫苗株作为多功能口服疫苗载体，用于表达和递送多种外源抗原，包括志贺氏菌O-抗原。在这项研究中，我们分别克隆了福氏志贺菌血清型2a和3a O-抗原生物合成所必需的基因，这些基因已被证明对多种疾病占主导地位的S。弗氏血清型。克隆的S. flexneri 2a rfb操纵子，沿着bat和gtrII，包含在SfII噬菌体上，足以在Ty2la中表达异源S.含有3，4个抗原决定簇的福氏2a O抗原。此外，该rfb操纵子与Sfx噬菌体上含有的gtrA、gtrB和gtrX以及Sf6噬菌体上含有的oac一起沿着足以表达S。含有6、7和8个抗原决定簇的福氏3a O-抗原。Ty2la与这些质粒携带的或染色体插入的基因一起，证明了同源S.伤寒O抗原加异源性S.弗氏菌O抗原表达异源S.福氏2a或3a脂多糖（LPS）引起针对这两种同源S.伤寒杆菌和异源志贺菌LPS对小鼠的保护作用。flexneri 2a或3a挑战。这些新的S。表达弗氏2a和3a O-抗原的Ty21a疫苗株，与我们先前构建的表达宋内志贺菌或志贺菌1 O-抗原的Ty21a菌株一起，具有一起用于同时保护抵抗全世界志贺菌病的主要原因以及伤寒的潜力。
We have been exploring the use of the live attenuated Salmonella enterica serovar Typhi Ty21a vaccine strain as a versatile oral vaccine vector for the expression and delivery of multiple foreign antigens, including Shigella O-antigens. In this study, we separately cloned genes necessary for the biosynthesis of the Shigello flexneri serotype 2a and 3a O-antigens, which have been shown to provide broad cross-protection to multiple disease-predominant S. flexneri serotypes. The cloned S. flexneri 2a rfb operon, along with bat and gtrII, contained on the SfIl bacteriophage, was sufficient in Ty2la to express the heterologous S. flexneri 2a O\-antigen containing the 3,4 antigenic determinants. Further, this rfb operon, along with gtrA, gtrB, and gtrX contained on the Sfx bacteriophage and oac contained on the Sf6 bacteriophage, was sufficient to express S. flexneri 3a O-antigen containing the 6, 7, and 8 antigenic determinants. Ty2la, with these plasmid-carried or chromosomally inserted genes, demonstrated simultaneous and stable expression of homologous S. Typhi O-antigen plus the heterologous S. flexneri O-antigen. Candidate Ty21a vaccine strains expressing heterologous S. flexneri 2a or 3a lipopolysaccharide (LPS) elicited significant serum antibody responses against both homologous S. Typhi and heterologous Shigella LPS and protected mice against virulent S. flexneri 2a or 3a challenges. These new S. flexneri 2a and 3a O-antigen-expressing Ty2la vaccine strains, together with our previously constructed Ty2la strains expressing Shigella sonnei or Shigella dysenteriae 1 O-antigens, have the potential to be used together for simultaneous protection against the predominant causes of shigellosis worldwide as well as against typhoid fever.