tetano
Editor, Senior Moderator
Sci Rep
. 2022 Mar 25;12(1):5207.
doi: 10.1038/s41598-022-09133-9.
Enoxaparin augments alpha-1-antitrypsin inhibition of TMPRSS2, a promising drug combination against COVID-19
Xiyuan Bai[SUP] #[/SUP][SUP] 1 2 3 4 [/SUP], Ashley M Buckle[SUP] #[/SUP][SUP] 5 [/SUP], Eszter K Vladar[SUP] 6 [/SUP], Edward N Janoff[SUP] 7 8 [/SUP], Reeti Khare[SUP] 9 [/SUP], Diane Ordway[SUP] 10 [/SUP], David Beckham[SUP] 8 [/SUP], Lorelenn B Fornis[SUP] 11 [/SUP], Abraham Majluf-Cruz[SUP] 12 [/SUP], Randolph V Fugit[SUP] 13 [/SUP], Brian M Freed[SUP] 14 [/SUP], Soohyun Kim[SUP] 15 16 [/SUP], Robert A Sandhaus[SUP] 11 [/SUP], Edward D Chan[SUP] 17 18 19 20 [/SUP]
Affiliations
Abstract
The cell surface serine protease Transmembrane Protease 2 (TMPRSS2) is required to cleave the spike protein of SARS-CoV-2 for viral entry into cells. We determined whether negatively-charged heparin enhanced TMPRSS2 inhibition by alpha-1-antitrypsin (AAT). TMPRSS2 activity was determined in HEK293T cells overexpressing TMPRSS2. We quantified infection of primary human airway epithelial cells (hAEc) with human coronavirus 229E (HCoV-229E) by immunostaining for the nucleocapsid protein and by the plaque assay. Detailed molecular modeling was undertaken with the heparin-TMPRSS2-AAT ternary complex. Enoxaparin enhanced AAT inhibition of both TMPRSS2 activity and infection of hAEc with HCoV-229E. Underlying these findings, detailed molecular modeling revealed that: (i) the reactive center loop of AAT adopts an inhibitory-competent conformation compared with the crystal structure of TMPRSS2 bound to an exogenous (nafamostat) or endogenous (HAI-2) TMPRSS2 inhibitor and (ii) negatively-charged heparin bridges adjacent electropositive patches at the TMPRSS2-AAT interface, neutralizing otherwise repulsive forces. In conclusion, enoxaparin enhances AAT inhibition of both TMPRSS2 and coronavirus infection. Such host-directed therapy is less likely to be affected by SARS-CoV-2 mutations. Furthermore, given the known anti-inflammatory activities of both AAT and heparin, this form of treatment may target both the virus and the excessive inflammatory consequences of severe COVID-19.
. 2022 Mar 25;12(1):5207.
doi: 10.1038/s41598-022-09133-9.
Enoxaparin augments alpha-1-antitrypsin inhibition of TMPRSS2, a promising drug combination against COVID-19
Xiyuan Bai[SUP] #[/SUP][SUP] 1 2 3 4 [/SUP], Ashley M Buckle[SUP] #[/SUP][SUP] 5 [/SUP], Eszter K Vladar[SUP] 6 [/SUP], Edward N Janoff[SUP] 7 8 [/SUP], Reeti Khare[SUP] 9 [/SUP], Diane Ordway[SUP] 10 [/SUP], David Beckham[SUP] 8 [/SUP], Lorelenn B Fornis[SUP] 11 [/SUP], Abraham Majluf-Cruz[SUP] 12 [/SUP], Randolph V Fugit[SUP] 13 [/SUP], Brian M Freed[SUP] 14 [/SUP], Soohyun Kim[SUP] 15 16 [/SUP], Robert A Sandhaus[SUP] 11 [/SUP], Edward D Chan[SUP] 17 18 19 20 [/SUP]
Affiliations
- PMID: 35338216
- DOI: 10.1038/s41598-022-09133-9
Abstract
The cell surface serine protease Transmembrane Protease 2 (TMPRSS2) is required to cleave the spike protein of SARS-CoV-2 for viral entry into cells. We determined whether negatively-charged heparin enhanced TMPRSS2 inhibition by alpha-1-antitrypsin (AAT). TMPRSS2 activity was determined in HEK293T cells overexpressing TMPRSS2. We quantified infection of primary human airway epithelial cells (hAEc) with human coronavirus 229E (HCoV-229E) by immunostaining for the nucleocapsid protein and by the plaque assay. Detailed molecular modeling was undertaken with the heparin-TMPRSS2-AAT ternary complex. Enoxaparin enhanced AAT inhibition of both TMPRSS2 activity and infection of hAEc with HCoV-229E. Underlying these findings, detailed molecular modeling revealed that: (i) the reactive center loop of AAT adopts an inhibitory-competent conformation compared with the crystal structure of TMPRSS2 bound to an exogenous (nafamostat) or endogenous (HAI-2) TMPRSS2 inhibitor and (ii) negatively-charged heparin bridges adjacent electropositive patches at the TMPRSS2-AAT interface, neutralizing otherwise repulsive forces. In conclusion, enoxaparin enhances AAT inhibition of both TMPRSS2 and coronavirus infection. Such host-directed therapy is less likely to be affected by SARS-CoV-2 mutations. Furthermore, given the known anti-inflammatory activities of both AAT and heparin, this form of treatment may target both the virus and the excessive inflammatory consequences of severe COVID-19.