The novel coronavirus SARS‐CoV‐2 is the causative agent of the global coronavirus disease 2019 (COVID‐19) outbreak. In addition to pneumonia, other COVID‐19‐associated symptoms have been reported, including loss of smell (anosmia). However, the connection between infection with coronavirus and anosmia remains enigmatic. It has been reported that defects in olfactory cilia lead to anosmia. In this Viewpoint, we summarize transmission electron microscopic studies of cilia in virus‐infected cells. In the human nasal epithelium, coronavirus infects the ciliated cells and causes deciliation. Research has shown that viruses such as influenza and Sendai attach to the ciliary membrane. The Sendai virus enters cilia by fusing its viral membrane with the ciliary membrane. A recent study on SARS‐CoV‐2–human protein–protein interactions revealed that the viral nonstructural protein Nsp13 interacts with the centrosome components, providing a potential molecular link. The mucociliary escalator removes inhaled pathogenic particles and functions as the first line of protection mechanism against viral infection in the human airway. Thus, future investigation into the virus–cilium interface will help further the battle against COVID‐19. The connection between coronavirus infection and anosmia remains enigmatic. Defects in olfactory cilia lead to anosmia. This viewpoint summarizes transmission electron microscopic studies of cilia in virus‐infected cells: Coronavirus infects the ciliated cells in human nasal epithelium and causes deciliation. Influenza viruses attach to the ciliary membrane, and Sendai virus enters cilia by fusing its viral membrane with the ciliary membrane.
【저자키워드】 COVID‐19, SARS‐CoV‐2, Smell loss, cilia,