Cell surface nucleolin facilitates enterovirus 71 binding and infection.

Area of Science:

• Virology
• Molecular Biology
• Glycoproteomics

Background:

• Enterovirus 71 (EV71) outbreaks cause significant mortality in young children.
• The precise mechanisms of EV71 binding, entry, and pathogenesis remain largely unknown.
• Identifying host factors involved in EV71 infection is crucial for understanding disease mechanisms.

Purpose of the Study:

• To identify novel host cell receptors and glycoproteins that interact with EV71 using glycoproteomic approaches.
• To characterize the role of cell surface nucleolin in mediating EV71 attachment, entry, and infection.
• To explore potential therapeutic targets for EV71 infection and develop new strategies for virus receptor identification.

Main Methods:

• Glycoprotein purification from human cell membrane extracts using lectin chromatography.
• Identification of EV71-binding glycoproteins via immunoprecipitation and tandem mass spectrometry.
• Validation of nucleolin's role through antibody-mediated inhibition, gene knockdown, and heterologous expression studies.

Main Results:

• Human nucleolin was identified as a novel EV71-binding receptor.
• EV71 directly interacts with nucleolin via its VP1 capsid protein.
• Knockdown of cell surface nucleolin reduced EV71 binding and infection; its expression on mouse cells conferred susceptibility to EV71.

Conclusions:

• Human nucleolin acts as a functional receptor mediating EV71 binding and cellular entry.
• Glycoproteomic strategies are effective for discovering pathogen receptors.
• Nucleolin represents a potential target for anti-EV71 drug development and understanding viral pathogenesis.