Tetraspanin CD81 regulates HSV-1 infection

Area of Science:

• Virology
• Cell Biology
• Immunology

Background:

• Tetraspanins regulate viral lifecycle stages, including entry, replication, and exit.
• Tetraspanin CD81 is known to influence HIV replication via SAMHD1 interaction.

Purpose of the Study:

• To investigate the role of CD81 in Herpes simplex virus 1 (HSV-1) infectivity.
• To analyze CD81's impact on HSV-1 replication using a neuroblastoma cell model.

Main Methods:

• Generated a CD81 knockout (KO) cell line utilizing CRISPR/Cas9 technology.
• Assessed viral entry, early protein marker expression, viral DNA replication, and infectious particle formation in CD81 KO cells post-HSV-1 infection.
• Analyzed SAMHD1 expression and localization in CD81 KO cells.

Main Results:

• CD81 KO cells exhibited no defects in HSV-1 entry or early protein expression.
• Expression of HSV-1 glycoproteins B and C was significantly reduced in CD81 KO cells.
• HSV-1 DNA replication and the production of infectious viral particles were severely compromised in CD81 KO cells.
• SAMHD1 relocalized to endosomal structures in CD81 KO cells, without changes in total expression.

Conclusions:

• CD81 plays a critical role in HSV-1 DNA replication and the production of infectious virions.
• CD81 deficiency impairs HSV-1 infectivity, likely through mechanisms involving SAMHD1 relocalization.
• Targeting CD81 may represent a novel strategy to control HSV-1 infection.