Bahy Rehab, Gaber Asmaa, Zedan Hamdallah, Mabrook Mona
Department of Microbiology and Immunology, Faculty of Pharmacy, Fayoum University, Fayoum, Egypt.
Department of Microbiology, General Division of Basic Medical Sciences, Egyptian Drug Authority (EDA), formerly National Organization for Drug Control and Research (NODCAR), Giza, Egypt.
Clin Exp Vaccine Res. 2023 Jan;12(1):70-76. doi: 10.7774/cevr.2023.12.1.70. Epub 2023 Jan 31.
Typhoid remains a major health problem, especially in the developing world. Furthermore, the emergence of multidrug-resistant and extensively drug-resistant strains of added a sense of urgency to develop more effective typhoid vaccines, one of which is bacterial ghosts (BGs), prepared by both genetic and chemical means. The chemical method includes incubation with numerous agents for a short time at their minimum inhibitory or minimum growth concentrations. This study included the preparation of BGs by a sponge-like reduced protocol (SLRP).
Critical concentrations of sodium dodecyl sulfate, NaOH, and HO were used. Moreover, high-quality BGs were visualized by scanning electron microscope (SEM). Subculturing was used to confirm the absence of vital cells. Besides, the concentrations of the released DNA and protein were estimated spectrophotometrically. In addition, the integrity of cells was proved by visualizing Gram-stained cells using a light microscope. Furthermore, a comparison between the immunogenicity and safety of the prepared vaccine and the available whole-cell killed vaccine was established.
Improved preparation of high-quality BGs of , visualized by SEM, revealed punctured cells with intact outer shells. Moreover, the absence of vital cells was confirmed by subculturing. At the same time, the release of respective amounts of proteins and DNA is another evidence of BGs' production. Additionally, the challenge test provided evidence that the prepared BGs are immunogenic and have the same efficacy as the whole cell vaccine.
The SLRP provided a simple, economical, and feasible method for BGs preparation.
伤寒仍然是一个主要的健康问题，尤其是在发展中世界。此外，多重耐药和广泛耐药菌株的出现增加了开发更有效伤寒疫苗的紧迫感，其中之一是通过基因和化学方法制备的细菌幽灵（BGs）。化学方法包括在最低抑菌浓度或最低生长浓度下与多种试剂短时间孵育。本研究包括采用海绵状简化方案（SLRP）制备BGs。
使用十二烷基硫酸钠、氢氧化钠和过氧化氢的临界浓度。此外，通过扫描电子显微镜（SEM）观察高质量的BGs。通过传代培养确认无活细胞。此外，用分光光度法估计释放的DNA和蛋白质的浓度。另外，通过光学显微镜观察革兰氏染色细胞来证明细胞的完整性。此外，还对制备的疫苗与现有的全细胞灭活疫苗的免疫原性和安全性进行了比较。
通过SEM观察到，改进后的高质量伤寒杆菌BGs制备显示细胞有穿孔但外壳完整。此外，传代培养证实无活细胞。同时，蛋白质和DNA的相应释放量是BGs产生的另一个证据。此外，攻毒试验证明制备的BGs具有免疫原性，且与全细胞疫苗具有相同的效力。
SLRP为BGs的制备提供了一种简单、经济且可行的方法。
