الفهرس | Only 14 pages are availabe for public view |
Abstract After a long time of global collaboration, we are near a polio-free world. However, the currently conventional inactivated polio vaccine (cIPV) is suboptimal for the post eradication phase. cIPV high production cost and biosafety risksobstruct its availability and global demand coverage. Manufacturing of IPV from the attenuated Sabin strains (sIPV) was a great solution and researchers work extensively to perfect a safe, effective, and affordable sIPV. This study investigated two main approaches for affordable sIPV; the capability of hydrogen peroxide (H₂O₂), ascorbic acid (AA) and epigallocatechin-3-gallate (EGCG) as alternatives for formaldehyde to inactivate Sabin-polioviruses strains and the use of Chitosan nanoparticles (CNPs) as adjuvants for sIPV production. Sabin-polioviruses vaccine strains were individually treated with AA, EGCG or H₂O₂ in comparison withformaldehyde. This was studied by determination of the inactivation kinetics on HEP2C cells, D-antigen preservation testing by ELISA and the immune response in Wistar rats of the four vaccine preparations. H₂O₂, AA and EGCG were capable of inactivation of polioviruses within 24 h while formaldehyde required 96 h. Significant high D-antigen levels were detected using AA, EGCG and H₂O₂ compared to formaldehyde while rat sera neutralizing antibodies test showed comparable results.CNPs{u2019} effect was investigated through the preparation of three trivalent sIPV formulations; the traditional formaldehyde and two of our experimental inactivating agents{u2019} AA and EGCG. Three concentrations were formulated with each vaccine preparation (100, 200 and 400 æg/ml) also, plain formulas without CNPs were used as control. Results of the loading efficiency percent (LE %) showed that the 100 æg/ml CNPs did not exceed 50% while the higher concentrations showed over 80% |