Department of Microbiology, Government College University Faisalabad, Pakistan.
Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia.
Biomed Res Int. 2021 Jan 29;2021:8879277. doi: 10.1155/2021/8879277. eCollection 2021.
Newcastle disease (ND) is a highly fatal, infectious, viral disease, and despite immunization with live and inactivated vaccines, the disease is still endemic, causing heavy morbidity and mortality leading to huge economic losses to the poultry industry in Pakistan. Therefore, the present study was aimed for the first time in the country at using novel virosomal technology to develop the ND vaccine using an indigenous highly virulent strain of the virus. ND virosome was prepared using Triton X-100, and SM2 Bio-Beads were used to remove the detergent and reconstitute the viral membrane into virosome. Confirmation was done by transmission electron microscopy and protein analysis by SDS-PAGE. cell adhesion property was observed by incorporating green fluorescent protein (GFP), producing plasmid into virosome and cell culture assay. Sterility, safety, and stability of the vaccine were tested before evaluation of immunogenicity and challenge protection study in commercial broiler. The virosome vaccine was administered (30 g/bird) at days 7 and 14 through the intranasal route in comparison with commercially available live and inactivated ND vaccines. Results revealed significantly high ( < 0.05) and clinically protective hemagglutination inhibition (HI) antibody titers at 7, 14, 21, and 28 days postimmunization with the virosome vaccine in comparison to the negative control. The GMTs were comparable to live and inactivated vaccines with nonsignificant ( > 0.05) differences throughout the experiment. Antibody levels increased in all vaccinated groups gradually from the 7 day and were maximum at 28-day postvaccination. In the virosome-administered group, GMT was 83.18 and 77.62 at 21 and 28-days postvaccination, respectively. Challenge revealed 100%, 90%, and 80% protection in virosome, live, and inactivated vaccinated groups, respectively. Under given experimental conditions, we can conclude that ND virosome vaccine prepared from the indigenous virus was found to be safe and immunogenic.
新城疫（ND）是一种高致命性、传染性的病毒性疾病，尽管使用活疫苗和灭活疫苗进行免疫，但该疾病仍在流行，导致家禽业发病率和死亡率高，给巴基斯坦的家禽业造成巨大的经济损失。因此，本研究首次在该国使用新型脂质体技术，使用本土高毒力病毒株开发 ND 疫苗。使用 Triton X-100 制备 ND 脂质体，并用 SM2 Bio-Beads 去除去污剂并将病毒膜重组为脂质体。通过透射电子显微镜和 SDS-PAGE 进行蛋白质分析来确认。通过将绿色荧光蛋白（GFP）、产生质粒掺入脂质体并进行细胞培养试验来观察细胞黏附特性。在对商业肉鸡进行免疫原性和攻毒保护研究之前，对疫苗的无菌性、安全性和稳定性进行了测试。脂质体疫苗在 7 日龄和 14 日龄通过鼻腔途径（30μg/只）给药，与市售的活疫苗和灭活疫苗进行比较。结果显示，与阴性对照组相比，脂质体疫苗在 7、14、21 和 28 天免疫后，血凝抑制（HI）抗体滴度显著升高（<0.05）且具有临床保护作用。整个实验过程中，GMT 与活疫苗和灭活疫苗相当，差异无统计学意义（>0.05）。所有接种组的抗体水平从第 7 天开始逐渐增加，在接种后 28 天达到最大值。在脂质体给药组中，GMT 在 21 天和 28 天免疫后分别为 83.18 和 77.62。攻毒试验表明，脂质体、活疫苗和灭活疫苗接种组的保护率分别为 100%、90%和 80%。在给定的实验条件下，我们可以得出结论，从本土病毒制备的 ND 脂质体疫苗被发现是安全和免疫原性的。
