Lung Surfactant Protein B Peptide Mimics Interact with the Human ACE2 Receptor

Area of Science:

• Biochemistry
• Pulmonary Medicine
• Virology

Background:

• Lung surfactant, a mix of phospholipids and proteins, is crucial for lung function and immunity.
• Exogenous surfactants aid premature infants and ARDS patients, including those with COVID-19.
• COVID-19 involves SARS-CoV-2 binding to ACE2, leading to lung damage and surfactant dysfunction.

Purpose of the Study:

• To investigate the potential of synthetic Surfactant Protein B (SP-B) peptide mimics as antiviral agents.
• To evaluate the binding of SP-B peptide mimics (Super Mini-B and B-YL) to the human ACE2 receptor.

Main Methods:

• Molecular docking simulations were employed to study peptide-receptor interactions.
• Surface plasmon resonance (SPR) was used to quantify the binding affinities of the peptides to the recombinant human ACE2 receptor.

Main Results:

• Both synthetic SP-B peptide mimics, Super Mini-B (SMB) and B-YL, demonstrated binding to the recombinant human ACE2 (rhACE2) receptor.
• The binding affinities of SMB and B-YL to rhACE2 were comparable to the affinity of the viral RBD-ACE2 complex.

Conclusions:

• Synthetic lung surfactant peptide mimics can effectively bind to the ACE2 receptor.
• These findings suggest that SMB and B-YL peptides may function as competitive inhibitors, blocking SARS-CoV-2 entry into cells.