PROS1 and COVID-19: One study suggested that the ATN-161 molecule inhibited the S protein interaction with α5β1 integrin, and the interaction of α5β1 integrin and ACE2 represents a promising approach to treat COVID-19.453 Mn2+ accelerates the cell entry of SARS-CoV-2 by inducing integrin extension and binding to high-affinity ligands.456 In addition, integrins found on the surfaces of pneumocytes, endothelial cells and platelets may be vulnerable to SARS-CoV-2 virion binding.