Infectious entry of reovirus cores into mammalian cells enhanced by transfection

Area of Science:

• Virology
• Molecular Biology
• Cell Biology

Background:

• Mammalian orthoreovirus virions possess complex structures with eight structural proteins in concentric capsid layers.
• Virions and infectious subvirion particles (ISVPs) are infectious, while reovirus cores are transcriptionally active but non-infectious due to lacking outer capsid entry signals.

Purpose of the Study:

• To directly test if purified reovirus cores can establish productive infections.
• To investigate the role of transfection reagents in enhancing core particle entry and infectivity.

Main Methods:

• Generation and purification of reovirus cores.
• Exposure of purified cores to cells with and without transfection reagents (lipofectamine).
• Testing infectivity across different reovirus serotypes (T1L, T3D) and cell types.

Main Results:

• Purified reovirus cores were essentially non-infectious when added directly to cells.
• The specific infectivity of core/lipofectamine mixtures increased over 10,000-fold.
• Similar results were observed across different serotypes and cell types, confirming the role of transfection reagents.

Conclusions:

• Transfection reagents significantly enhance the entry of reovirus cores into cells.
• Reovirus cores contain all necessary components for replication once inside the cell.
• This method holds promise for improved genetic manipulations and enhanced use of reovirus as an anti-cancer agent.