Blocking Coronavirus Infection in the Lung with Fusion Proteins
COVID-19 is caused by the novel coronavirus, SARS-CoV-2, infecting the respiratory system. Specifically, the spike protein (S1 subunit) of the virus binds to a protein receptor called angiotensin converting enzyme 2 (ACE2) on lung epithelial cells. This interaction is a key step for the virus entering and continuing its lifecycle in the lungs. Other proteins, such as surfactant protein-D, promote local immunity. Wei Shi, MD, PhD, has received funding from The Saban Research Institute of Children’s Hospital Los Angeles for pre-clinical experiments aimed at blocking critical steps in coronavirus infection. The idea behind his work is to introduce novel recombinant proteins (a free form of spike protein or ACE2 fused with surfactant protein-D, which promotes lung immunity). These recombinant proteins sit on the surface of the lung cells and prevent the viral infection by competitively inhibiting the interaction between the coronavirus and ACE2.