Handheld virus concentration method using a hollow fiber filter module.

A virus concentration method is required for viral vaccine manufacturing and virus-related research. However, concentration methods, such as ultracentrifugation, often require capital investment. We report a simple and easy-to-use handheld syringe method for virus concentration using a hollow fiber (HF) filter module, which can be applicable to viruses of different sizes, without incorporating any special machines or reagents. This virus concentration method does not use pumps, which might cause shear stress for virus particles; therefore, it is useful for stress-sensitive virus particles, and virus-like particles, as well as other proteins. The clarified harvest of flavivirus (Zika virus) was concentrated using an HF filter module and compared with a centrifugal ultrafiltration device (CUD) for demonstration of the HF filter method. The HF filter method achieved concentration of the virus solution in less time than the CUD. The yield comparison of the recovered virus solution indicated that recovery from the developed method was comparable to using the CUD, and infectivity was maintained throughout.•The Zika virus was concentrated from 200 mL to 5 mL within 45 min using the HF filter and handheld syringe module method.•The handheld HF filter method may be applicable to stress-sensitive viruses and proteins of different sizes.•The virus concentration process should be conducted in a safety cabinet, which is preferred for virus containment.

Physicochemical Characterization of Sabin Inactivated Poliovirus Vaccine for Process Development.

Upscaling the production capacity of inactivated poliovirus vaccines (IPV) is urgently needed to eradicate polio worldwide. For the development of a robust manufacturing process for IPV, the impact of stresses on the properties of the poliovirus during manufacturing needs to be carefully evaluated. In this study, the physicochemical properties of Sabin poliovirus after low pH exposure were analyzed by asymmetrical flow field-flow fractionation coupled to multi-angle laser light scattering (AF4-MALS), sedimentation velocity analytical ultracentrifugation (SV-AUC), transmission electron microscopy (TEM), dynamic light scattering (DLS) and surface plasmon resonance (SPR). Low pH stress caused structural changes and aggregation of inactivated poliovirus virions, whereas degraded virion particles would not revert to native virions even after neutralization. Importantly, a complete loss of the D-antigenicity of IPV by low pH stress, followed by neutralization, was observed in SPR. These results suggest that the exposure of poliovirus particle to low pH stress would induce irreversible denaturation and aggregation of virus particles and lead to the loss of D-antigenicity; thus, low pH stress during the manufacturing of poliovirus vaccine should be minimized. The analytical methods above can be efficiently utilized in the development of high-integrity manufacturing processes and high-quality vaccines.