| Id |
Subject |
Object |
Predicate |
Lexical cue |
| T64 |
0-91 |
Sentence |
denotes |
The S protein of SARS-CoV-2 is cleaved by host proteases into two subunits, S1 and S2 [19]. |
| T65 |
92-275 |
Sentence |
denotes |
The S1 subunit binds to the host cell surface receptor angiotensin-converting enzyme 2 (ACE2) for virus attachment, and the S2 subunit fuses the virus and the host cell membrane [19]. |
| T66 |
276-664 |
Sentence |
denotes |
The investigation of the effect of CQ on ACE2 in VeroE6 cells showed that effective anti-SARS-CoV-2 concentrations of CQ had no significant effect on the synthesis and glycosylation of S protein on the surface of SARS-CoV, and although it had no significant effect on the cell surface expression of ACE2, CQ could destroy the glycosylation at the terminal glycosylation site of ACE2 [13]. |
| T67 |
665-938 |
Sentence |
denotes |
Therefore, the mechanism of anti-CoV activity of CQ/HCQ may be at least partly related to the impairment of terminal glycosylation of ACE2, which may result in reduced binding affinities between ACE2 and SARS CoV S protein, thereby blocking receptor recognition (Figure 1). |
| T68 |
939-948 |
Sentence |
denotes |
Figure 1. |
| T69 |
949-1067 |
Sentence |
denotes |
Schematic representation of the possible mechanisms of CQ/HCQ against CoVs replication and modulating immune response. |
| T70 |
1068-1699 |
Sentence |
denotes |
CQ/HCQ may synergistically exert antiviral and immunomodulatory effects on COVID-19 through multiple mechanisms including hindering the receptor recognition process by influencing the affinity of ACE2 and S protein, and the affinity for sialic acid and ganglioside; inhibiting the membrane fusion process by suppressing endolysosome acidification; suppressing the p38 activation and affecting host defense machinery, and preventing MHC class II expression (block expression of CD154 on the surface of CD4 + T cell) and TLR signaling and reducing the production of cytokines through inhibiting the activation of T cells and B cells. |
| T71 |
1700-2050 |
Sentence |
denotes |
ACE2, angiotensin-converting enzyme 2; COVID-19, coronavirus disease 2019; CQ, chloroquine; HCQ, hydroxychloroquine; CoVs, coronaviruses; MAPK, mitogen-activated protein kinase; MHC-II, major histocompatibility complex class II; TLR, toll-like receptor; cGAS, cyclic GMP-AMP synthase; IFN, interferon; IL, interleukin; TNF-α, tumor necrosis factor-α. |
