The spike protein on the surface of the new coronavirus virus possesses more than one "key" to help it break into cells, researchers say. The virus is known to hijack ACE2 receptors, using them as an entryway into healthy cells, but researchers have discovered that it uses a second region on the spike to hijack a cell-surface protein called neuropilin-1. "Having keys to both ACE2 and neuropilin-1 significantly enhances the entry of the virus," Yohei Yamauchi of the University of Bristol in the UK told Reuters. Neuropilin-1 is present in many tissues, he noted, including the lining of the respiratory tract, which is the primary site of coronavirus infection. While the infection process depends on ACE2, in vitro experiments suggest that blocking neuropilin-1 with a drug or an antibody could reduce the ability of the virus to break into cells, Yamauchi's team reported in Science. In a separate paper in the same issue of the journal, scientists from Germany and Finland reported that neuropilin-1 facilitates SARS-CoV-2 cell entry and infectivity. "There are existing medications that have been developed to block neuropilin-1 for cancer and lung disease, but these have not yet fully progressed through clinical trials," Yamauchi said. "Our data does suggest that these drugs could potentially be repurposed for the treatment of COVID-19." —Reuters Staff Source
