Article Figures & Data
Figures
- FIG 1
Schematic structure of the SARS-CoV-2 virion.
- FIG 2
The entry of human coronaviruses into the host cell. Coronaviruses first interact with an adhesion molecule (e.g., heparan sulfate proteoglycans [HSPGs] for HCoV-NL63 [32], SARS-CoV [33], and [possibly] SARS-CoV-2 [409]; N-acetyl-9-O-acetylneuraminic acid [Neu5Ac] for HCoV-HKU1 and HCoV-OC43 [34]; or carcinoembryonic antigen-related cell adhesion molecule 5 [CEACAM5] for MERS-CoV [35]). Next, the virus interacts with the entry receptor (aminopeptidase N [APN] for HCoV-229E [36]; dipeptidyl peptidase 4 [DPP4] for MERS-CoV [37]; 9-O-acetylated sialic acid for HCoV-OC43 [39]; or angiotensin-converting enzyme 2 [ACE2] for HCoV-NL63, SARS-CoV, and SARS-CoV-2 [40]). Recently, neuropilin 1 (NRP1) was reported to enhance the SARS-COV-2 entry (41, 42). To enter the cell, the S protein requires proteolytic priming, which may occur on the cell surface (TMPRSS2, TMPRSS4, kallikrein 13) or after endosomal entry (cathepsin B [catB] and cathepsin L [catL]) (43–50, 410–414).
- FIG 3
Cell types and their localization within the human respiratory tract.
- FIG 4
Cell types and their localization in the human intestine.
- FIG 5
Cell types and their localization in the cardiovascular system.
- FIG 6
Organs affected by COVID-19. The solid and dotted lines indicate direct and indirect viral replication, respectively.
