SARS-CoV-2 peptides bind to NKG2D and increase NK cell activity

Area of Science:

• Immunology
• Virology
• Molecular Biology

Background:

• Immune dysregulation is a hallmark of COVID-19.
• SARS-CoV-2 infection leads to lung inflammation and innate immune cell dysfunction.
• The specific interactions between SARS-CoV-2 and innate immune cells, like NK cells, remain unclear.

Purpose of the Study:

• To investigate the interaction between SARS-CoV-2 and natural killer (NK) cells.
• To identify SARS-CoV-2 S protein peptides that bind to the NKG2D receptor on NK cells.
• To elucidate the functional consequences of this interaction.

Main Methods:

• In silico screening of SARS-CoV-2 S protein peptides for NKG2D receptor binding.
• In vitro assays to assess NK cell cytotoxicity and interferon gamma (IFN-γ) production.
• Analysis of downstream signaling pathways, including Vav1 phosphorylation.

Main Results:

• Two SARS-CoV-2 S protein peptides (cov1 and cov2) were identified that bind to NK cells and the NKG2D receptor.
• These peptides enhanced NK cell cytotoxicity against lung cancer cells.
• Cov peptides stimulated IFN-γ production by NK cells, potentially via Vav1 phosphorylation.

Conclusions:

• A direct interaction between SARS-CoV-2 and NK cells has been identified.
• This interaction modulates NK cell function, including cytotoxicity and cytokine production.
• Targeting this SARS-CoV-2-NK cell interaction presents a novel therapeutic strategy for COVID-19.