Researchers at Colorado State University have developed a two-plasmid infectious clone system for Zika virus that closely replicates the behavior of naturally occurring strains. This system produces viruses with nearly identical growth, transmission, and disease characteristics as the original isolate. It works in both human and mosquito cells and accurately models infection in animal systems. The technology provides a reliable and reproducible platform for studying Zika virus biology. It enables faster progress in vaccine, therapeutic, and diagnostic development.
Zika virus is a globally significant pathogen linked to severe neurological conditions, including birth defects and Guillain-Barré syndrome. Understanding how the virus spreads and causes disease has been limited by the lack of accurate laboratory models. Many existing infectious clone systems produce weakened viruses that do not fully reflect real-world infection. A system that closely mimics wild-type virus behavior is essential for advancing research and developing effective countermeasures.
This technology consists of a two-plasmid infectious clone system (pJW231 and pJW232) derived from a clinically relevant 2015 Puerto Rico Zika virus strain (PRVABC59). The system splits the viral genome into two stable components, which are assembled and transcribed into infectious RNA. When introduced into host cells, this RNA produces live virus that are nearly identical to the original isolate in genetic sequence, replication behavior, and biological function.
The resulting virus demonstrates replication kinetics in human, mammalian, and mosquito cell lines that are indistinguishable from wild-type virus. It achieves high viral titers (up to ~1.25 × 10⁷ PFU/mL) and shows comparable infection and transmission rates in Aedes aegypti mosquitoes, with infection rates reaching 75–100% and transmission rates around 40–60%. In mouse models, the clone-derived virus produces similar disease progression, viral load, and mortality as the original strain, confirming that it is not attenuated and accurately reflects real infection dynamics.
Biological Materials
Brian J Geiss
Gregory D Ebel
Steve Foster
Steve.Foster@colostate.edu
970-491-7100