Construction and immunogenicity in mice of attenuated Salmonella typhi expressing Plasmodium falciparum merozoite surface protein 1 (MSP-1) fused to tetanus toxin fragment C.
Construction and immunogenicity in mice of attenuated Salmonella typhi expressing Plasmodium falciparum merozoite surface protein 1 (MSP-1) fused to tetanus toxin fragment C.
复制标题
表达与破伤风毒素片段 C 融合的恶性疟原虫裂殖子表面蛋白 1 (MSP-1) 的减毒伤寒沙门氏菌的构建及其在小鼠中的免疫原性。
DOI：
10.1016/s0168-1656(00)00306-0
复制
发表时间：
2000
影响因子：
4.1
通讯作者：
Levine,MM
中科院分区：
文献类型：
--
作者：
Wu,S;Beier,M;Sztein,MB;Galen,J;Pickett,T;Holder,AA;Gómez-Duarte,OG;Levine,MM
开发多抗原疟疾疫苗的一种策略是使用活载体将推定的保护性恶性疟原虫抗原携带至免疫系统。恶性疟原虫裂殖子表面蛋白1（MSP-1）的19 kDa羧基末端与破伤风毒素的片段C基因融合，并在减毒伤寒沙门氏菌CVD 908中表达，MSP-1是红细胞侵入所必需的，并且是用于包含在多价疟疾疫苗中的主要抗原。在细菌细胞质中的条件下，片段C-MSP-1融合不形成MSP-1的表皮生长因子（EGF）样结构域;单克隆抗体在从活载体超声处理物提取的非变性蛋白质的免疫印迹中未能识别这些构象结构域。然而，MSP-1是免疫原性的。在用活载体构建体鼻内免疫BALB/c小鼠后一个月，通过ELISA（GMT=211），5只小鼠中有4只表现出抗MSP-1升高≥ 4倍;单次鼻内加强免疫进一步提高了滴度（GMT=1280）。通过间接免疫荧光测定，免疫后血清识别裂殖子上的天然MSP-1。这些数据鼓励优化MSP-1在S.伤寒沙门氏菌（例如作为分泌蛋白），从而可以形成EGF样表位，推测其是刺激保护性抗体所必需的。
One strategy to develop a multi-antigen malaria vaccine is to employ live vectors to carry putative protective Plasmodium falciparum antigens to the immune system. The 19 kDa carboxyl terminus of P. falciparum merozoite surface protein 1 (MSP-1), which is essential for erythrocyte invasion and is a leading antigen for inclusion in a multivalent malaria vaccine, was genetically fused to fragment C of tetanus toxin and expressed within attenuated Salmonella typhi CVD 908. Under conditions in the bacterial cytoplasm, the fragment C-MSP-1 fusion did not form the epidermal growth factor (EGF)-like domains of MSP-1; monoclonal antibodies failed to recognize these conformational domains in immunoblots of non-denatured protein extracted from live vector sonicates. The MSP-1 was nevertheless immunogenic. One month following intranasal immunization of BALB/c mice with the live vector construct, four out of five mice exhibited ≥four-fold rises in anti-MSP-1 by ELISA (GMT=211); a single intranasal booster raised titers further (GMT=1280). Post-immunization sera recognized native MSP-1 on merozoites as determined by indirect immunofluorescence. These data encourage efforts to optimize MSP-1 expression in S. typhi (e.g. as a secreted protein), so that the EGF-like epitopes, presumably necessary for stimulating protective antibodies, can form.