Objectives

This study was design to explore the immunogenic behavior of LamB and SpaO outer membrane protein of Salmonella serovar Typhi against enteric fever in BALB/c mice.

Methods

SpaO or LamB genes of locally isolated strain of S.Typhi was amplified, cloned and expressed. Recombinant protein SpaO and LamB were purified and lyophilized to prepare aluminum hydroxide Gel precipitated vaccine. Clinical trials were performed in BALB/c mice. The Immunoprophylactic potential of recombinant SpaO or LamB alone and in combination at different concentrations were determined using Complement fixation test along with whole culture attenuated and commercial vaccine.

Results

The immune response of rSpaO and rLamB proteins in combination at 500 µg/ml was significantly high at 48th day and maintained until 60^thday. Protective immune potential of recombinant monovalent and multivalent vaccine assessed upon challenge in mice with 10⁹ cells of S.Typhi virulent culture. Out of five, no mice could survive in control group although rSpaO and rLamB in combination at 500 µg/ml conferred 80 % protection. Whereas the monovalent rSpaO and rLamB vaccine elucidate protection 60 % or 40 % respectively.

Conclusion

From this study, it is conclude that combine vaccine rSpaO and rLamB effectively enhanced the immunological response and withstand the challenge of the causative agent more effectively as compared to the monovalent vaccines.

中文翻译：

---

伤寒沙门氏菌重组外膜蛋白对 BALB/c 小鼠肠热病的免疫预防潜力

目标

本研究旨在探讨伤寒沙门氏菌LamB和SpaO外膜蛋白对BALB/c小鼠肠热病的免疫原性行为。

方法

对本地分离的伤寒沙门氏菌SpaO或LamB基因进行了扩增、克隆和表达。将重组蛋白SpaO和LamB纯化并冻干，制备氢氧化铝凝胶沉淀疫苗。在 BALB/c 小鼠中进行了临床试验。使用补体结合试验以及全培养物减毒疫苗和商业疫苗测定重组 SpaO 或 LamB 单独和不同浓度组合的免疫预防潜力。

结果

500 µg/ml rSpaO 和 rLamB 蛋白组合的免疫反应在第 48 天时显着较高，并维持到第 60^天。^{重组单价和多价疫苗的保护性免疫潜力在对具有 10 9 个}伤寒沙门氏菌强毒培养物的小鼠进行攻击时进行了评估。尽管 500 µg/ml 的 rSpaO 和 rLamB 组合可提供 80% 的保护，但对照组中五只小鼠均无法存活。而单价 rSpaO 和 rLamB 疫苗的保护作用分别为 60% 或 40%。

结论

从这项研究中得出的结论是，与单价疫苗相比，rSpaO和rLamB联合疫苗可有效增强免疫反应并更有效地抵御病原体的攻击。