Microfluidic electrical cell lysis for high-throughput and continuous production of cell-free varicella-zoster virus.

• A microfluidic device integrated with arrays of microelectrode was developed to continuously produce cell-free VZV. • Multiple constricted channels and microelectrode arrays were designed to generate a high electrolysis efficiency. • The integrated microfluidic platform accomplished a production yield of 1.4 – 2.1×104 PFU mL–1 of cell-free VZV. • Rapid and high-throughput production of the high-titer cell-free viruses was obtained with relatively low voltage input. Varicella-zoster virus (VZV), the causative agent of varicella and herpes zoster, is highly cell-associated and spreads via cell-to-cell contact in tissue culture. The lack of cell-free VZV hampers studies on VZV biology as well as antiviral and vaccine development. In the present study, a poly(methylmethacrylate) microfluidic device integrated with arrays of microelectrode was fabricated to continuously electrolyse VZV-infected cells to produce cell-free viruses. By designing multiple constrictions and microelectrode arrays, a high electric field is focused on the constricted region of the microchannel to disrupt large numbers of virus-infected cells with high-throughput on a microfluidic platform. Plaque assay and scanning electron microscopy were conducted to quantify and characterize cell-free VZV produced using the microfluidic continuous-flow electrical cell lysis device. The process of microfluidic electrical cell lysis followed by subsequent filtration and virus concentration process yielded a 1.4–2.1 × 104 plaque-forming units (PFUs) per mL of cell-free VZV from 7.0 × 106 VZV-infected human foreskin fibroblasts (HFF) cells. The high electric field formed inside a microfluidic channel combined with the continuous-flow of virus-infected cells within the microchannel enabled the rapid and efficient production of high-titer cell-free virus in large quantities with relatively low input of the voltage. [ABSTRACT FROM AUTHOR]