Written by: Sam Bazzi Edited by: Esther Melamed At any other time, celebrating the advent of January 1st is a ritual that allows us to reflect on the past 12 months, find hope for the upcoming year, and make resolutions to improve our lives. Unfortunately, SARS-CoV-2 did not get the memo about the new year and its deadly second wave is still reverberating around the country and the world, making the annual transition feel rather arbitrary as we remain in lockdown. Nevertheless it is important to do our best to maintain our new year ritual and the feelings of renewal it would normally …
SARS-CoV-2 Enters the CNS via Olfactory Mucosa
Before the Thanksgiving holiday, I wrote a blog post about a study that described enhanced SARS-CoV-2 entry into cells that express the neuropilin-1 receptor (NRP1). The main takeaway from that piece was that while NRP1 is not sufficient for viral entry, it greatly enhances viral entry when coexpressed with ACE2 and TMPRSS2, the two proteins responsible for entry. The authors of the study had also found that NRP1 was highly expressed in cells isolated from the bronchoalveolar lavage fluid from COVID-19 patients relative to control patients. Overall, this study suggested that NRP1 expression in …
Beyond ACE2 and TMPRSS2: Neuropilin-1 Receptors Enhance Cellular Entry of SARS-CoV-2
Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) have been established as the sites of entry for the SARS-CoV-2 virus into cells, but a new study published in Science demonstrates that another cell surface receptor, neuropilin-1 (NRP1), enhances the infectivity of the virus in vitro and in mice (Cantuti-Castelvetri et al., 2020). Of note, NRP1 is highly expressed in the olfactory system. The theoretical basis of this study began with the identification of a polybasic furin-type cleavage site at the S1-S2 junction in the spike protein. This polybasic …