Virus neutralisation by intracellular antibodies

Area of Science:

• Immunology
• Virology
• Cell Biology

Background:

• Antibodies were traditionally considered extracellular effectors.
• Emerging research reveals significant intracellular antiviral functions of antibodies.
• Understanding these intracellular mechanisms is crucial for developing new antiviral strategies.

Purpose of the Study:

• To review the mechanisms by which antibodies neutralize viruses within host cells.
• To highlight the diverse intracellular stages targeted by antibody-mediated viral control.
• To underscore the potential of intracellular antibody activity in therapeutic and vaccine development.

Main Methods:

• Review of existing scientific literature on antibody effector functions.
• Analysis of studies demonstrating antibody efficacy at various intracellular viral life cycle stages.
• Examination of mechanisms including endosomal and cytosolic neutralization, and TRIM21 recruitment.

Main Results:

• Antibodies neutralize viruses in endosomes by inhibiting uncoating, fusion, or particle egress.
• Cytosolic neutralization is mediated through the intracellular antibody receptor TRIM21.
• Antibodies indirectly control viruses by enhancing MHC class I presentation and CD8 T cell responses.

Conclusions:

• Intracellular antibody neutralization is a critical antiviral defense mechanism.
• Antibodies offer potent protection against viruses at multiple intracellular stages.
• Targeting intracellular antibody functions presents a promising avenue for novel antiviral therapies and vaccines.