is there any alternative receptor for sars-cov-2?

Angiotensin-converting enzyme ii (ace2) in association with type ii transmembrane serine protease (tmprss2) is considered the main receptor of sars-cov-2. however, considering the clinical complications of covid-19 in different organs, there is no strong association between the abundance of ace2/tmprss2 co-expression and clinical features of the disease and the severity of complications. since sars-cov-2 affects certain organs that lack or have low expression of ace2/tmprss2, it may be possible that the virus employs other receptors for colonization and entry. based on recent studies, glucose-regulated protein 78 (grp78) can be a potential alternative receptor for sars-cov-2 entry. in this letter, supporting evidence proposed grp78 as an alternative receptor in sars-cov-2 infection.