Institute of Military Veterinary Science, Academy of Military Medical Sciences, Changchun, China.
Lett Appl Microbiol. 2012 Mar;54(3):255-62. doi: 10.1111/j.1472-765X.2011.03202.x.
To prepare enteropathogenic Escherichia coli (EPEC) E2348/69 ghosts and investigate whether immunization with EPEC bacterial ghosts can elicit protective immune responses.
A recombinant plasmid with double λPL/PR-cI857 temperature-sensitive regulatory cassettes was constructed. The lysis gene E and/or the staphylococcal nuclease A (SNA) gene were separately inserted downstream of the two regulatory cassettes to construct the lysis plasmids pBV220::E and pBV220::E::CI-P-SNA. An EPEC reference strain E2348/69 (serotype O127:H6) was transformed with the lysis plasmids to produce EPEC ghosts. Mice injected with bacterial ghosts EGE (EPEC ghosts produced using lysis protein E) or EGES (EPEC ghosts produced using a combination of lysis protein E and SNA) gained weight normally and showed no clinical signs of disease. Vaccination trials showed that mice immunized with EGE or EGES were significantly protected against subsequent challenge with the wild-type virulent parent strain, EPEC E2348/69 (42/50 and 45/50 survival, respectively); in contrast, none of the 30 control mice survived.
Immunization with EPEC ghosts can elicit protective immune responses in BALB/c mice.
EPEC ghosts may represent a promising new approach for vaccination against EPEC infection.
制备肠致病性大肠杆菌（EPEC）E2348/69 噬菌体并研究用 EPEC 细菌噬菌体免疫是否能引起保护性免疫应答。
构建了一个带有双 λPL/PR-cI857 温度敏感调控盒的重组质粒。将裂解基因 E 和/或金黄色葡萄球菌核酸酶 A（SNA）基因分别插入两个调控盒的下游，构建了裂解质粒 pBV220::E 和 pBV220::E::CI-P-SNA。用裂解质粒转化 EPEC 参考株 E2348/69（血清型 O127:H6），产生 EPEC 噬菌体。用细菌噬菌体 EGE（用裂解蛋白 E 产生的 EPEC 噬菌体）或 EGES（用裂解蛋白 E 和 SNA 联合产生的 EPEC 噬菌体）免疫的小鼠体重正常增加，没有出现疾病的临床症状。疫苗接种试验表明，用 EGE 或 EGES 免疫的小鼠对随后用野生型毒力亲本菌株 EPEC E2348/69 的攻毒具有显著的保护作用（分别有 42/50 和 45/50 的存活率）；相比之下，对照组的 30 只小鼠无一存活。
用 EPEC 噬菌体免疫可引起 BALB/c 小鼠产生保护性免疫应答。
EPEC 噬菌体可能代表了针对 EPEC 感染的疫苗接种的一种很有前途的新方法。
