Razak Abdul, Altaf Imran, Ahmad Anjum Aftab, Raza Awan Ali
Institute of Microbiology, University of Veterinary and Animal Sciences, Syed Abdul Qadir Jillani (Out Fall) Road, Lahore 54000, Pakistan.
Institute of Biochemistry, and Biotechnology, University of Veterinary, and Animal Sciences, Syed Abdul Qadir Jillani (Out Fall) Road, Lahore 54000, Pakistan.
Saudi J Biol Sci. 2023 Jul;30(7):103709. doi: 10.1016/j.sjbs.2023.103709. Epub 2023 Jun 16.
Foot and Mouth Disease (FMD) is globally pandemic which badly affect the economics of livestock based countries like Pakistan. There are different types of Foot and Mouth Disease Virus (FMDV) among these types O is most prevalent in Pakistan. Recently Pakistan is producing approximately fifteen million doses of non-purified FMD vaccine against the demand of 160 million doses annually. More over the Pakistan is still striving for the development and optimization of concentration as well as purification of FMDV. The present project was designed to develop the technology for the purification of FMDV indigenously. The locally isolated and adapted FMDV type O virus was propagated on adherent culture of BHK-21cells to get final volume of virus one liter. This virus suspension was concentrated by peggylation as well as ultra-filtration method. The purification and quantification of concentrated virus was done by size exclusion chromatography. The results showed that peggylation is better method of concentration up to 603.75 µg/ml with 82.80 % recovery rate than ultra-filtration with 43.90 % followed by chromatography for purification. The PD was calculated in bovines at 24, 12, 6, 3 and 1.5 µg of FMDV Ag/dose and it revealed that antigen load of 1.98 µg is the dose, where the 50 % of inoculated animals showed the protective antibody level based upon percent inhibition through antibody detecting ELISA. According to the British pharmacopeia, the vaccine should contain 3PD which found equivalent to our findings about 6 µg/dose. The group of animal injected with 6/dose (3.23PD50) showed protective titer up to 20th week post priming.
口蹄疫在全球流行，严重影响了像巴基斯坦这样以畜牧业为主的国家的经济。口蹄疫病毒（FMDV）有不同类型，其中O型在巴基斯坦最为普遍。最近，巴基斯坦每年生产约1500万剂非纯化口蹄疫疫苗，而每年的需求量为1.6亿剂。此外，巴基斯坦仍在努力开发和优化口蹄疫病毒的浓缩及纯化方法。本项目旨在自主研发口蹄疫病毒的纯化技术。将本地分离并适应的O型口蹄疫病毒在BHK - 21细胞的贴壁培养物上增殖，以获得1升病毒终体积。该病毒悬液通过聚乙二醇化以及超滤方法进行浓缩。浓缩病毒的纯化和定量通过尺寸排阻色谱法进行。结果表明，聚乙二醇化是更好的浓缩方法，浓缩至603.75μg/ml，回收率为82.80%，优于超滤法（回收率43.90%），随后通过色谱法进行纯化。在牛身上以24、12、6、3和1.5μg口蹄疫病毒抗原/剂量计算PD，结果显示抗原负荷为1.98μg时为该剂量，在此剂量下，50%的接种动物通过抗体检测ELISA基于抑制百分比显示出保护性抗体水平。根据英国药典，疫苗应含有3PD，这与我们发现的约6μg/剂量相当。注射6μg/剂量（3.23PD50）的动物组在初次免疫后第20周显示出保护性滴度。
