PMID- 34252168
OWN - NLM
STAT- MEDLINE
DCOM- 20210805
LR  - 20231101
IS  - 1553-7374 (Electronic)
IS  - 1553-7366 (Print)
IS  - 1553-7366 (Linking)
VI  - 17
IP  - 7
DP  - 2021 Jul
TI  - Strategies to target SARS-CoV-2 entry and infection using dual mechanisms of 
      inhibition by acidification inhibitors.
PG  - e1009706
LID - 10.1371/journal.ppat.1009706 [doi]
LID - e1009706
AB  - Many viruses utilize the host endo-lysosomal network for infection. Tracing the 
      endocytic itinerary of SARS-CoV-2 can provide insights into viral trafficking and 
      aid in designing new therapeutic strategies. Here, we demonstrate that the 
      receptor binding domain (RBD) of SARS-CoV-2 spike protein is internalized via the 
      pH-dependent CLIC/GEEC (CG) endocytic pathway in human gastric-adenocarcinoma 
      (AGS) cells expressing undetectable levels of ACE2. Ectopic expression of ACE2 
      (AGS-ACE2) results in RBD traffic via both CG and clathrin-mediated endocytosis. 
      Endosomal acidification inhibitors like BafilomycinA1 and NH4Cl, which inhibit 
      the CG pathway, reduce the uptake of RBD and impede Spike-pseudoviral infection 
      in both AGS and AGS-ACE2 cells. The inhibition by BafilomycinA1 was found to be 
      distinct from Chloroquine which neither affects RBD uptake nor alters endosomal 
      pH, yet attenuates Spike-pseudovirus entry. By screening a subset of FDA-approved 
      inhibitors for functionality similar to BafilomycinA1, we identified Niclosamide 
      as a SARS-CoV-2 entry inhibitor. Further validation using a clinical isolate of 
      SARS-CoV-2 in AGS-ACE2 and Vero cells confirmed its antiviral effect. We propose 
      that Niclosamide, and other drugs which neutralize endosomal pH as well as 
      inhibit the endocytic uptake, could provide broader applicability in subverting 
      infection of viruses entering host cells via a pH-dependent endocytic pathway.
FAU - Prabhakara, Chaitra
AU  - Prabhakara C
AUID- ORCID: 0000-0003-0915-4017
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Godbole, Rashmi
AU  - Godbole R
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
AD  - University of Trans-Disciplinary Health Sciences and Technology (TDU), Bengaluru, 
      India.
FAU - Sil, Parijat
AU  - Sil P
AUID- ORCID: 0000-0002-8391-8110
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Jahnavi, Sowmya
AU  - Jahnavi S
AUID- ORCID: 0000-0002-2923-3938
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Gulzar, Shah-E-Jahan
AU  - Gulzar SE
AUID- ORCID: 0000-0003-0489-9888
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
AD  - SASTRA University, Thanjavur, India.
FAU - van Zanten, Thomas S
AU  - van Zanten TS
AUID- ORCID: 0000-0002-8810-7149
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Sheth, Dhruv
AU  - Sheth D
AUID- ORCID: 0000-0003-2728-3322
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Subhash, Neeraja
AU  - Subhash N
AUID- ORCID: 0000-0002-0241-1984
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
AD  - SASTRA University, Thanjavur, India.
FAU - Chandra, Anchal
AU  - Chandra A
AUID- ORCID: 0000-0003-4096-4771
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Shivaraj, Akshatha
AU  - Shivaraj A
AUID- ORCID: 0000-0001-7185-8803
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Panikulam, Patricia
AU  - Panikulam P
AUID- ORCID: 0000-0003-0647-0030
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - U, Ibrahim
AU  - U I
AUID- ORCID: 0000-0003-1374-8969
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Nuthakki, Vijay Kumar
AU  - Nuthakki VK
AUID- ORCID: 0000-0002-7454-1948
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Puthiyapurayil, Theja Parassini
AU  - Puthiyapurayil TP
AD  - Institute for Stem Cell Science and Regenerative Medicine (inSTEM), Bengaluru, 
      India.
FAU - Ahmed, Riyaz
AU  - Ahmed R
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Najar, Ashaq Hussain
AU  - Najar AH
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Lingamallu, Sai Manoz
AU  - Lingamallu SM
AUID- ORCID: 0000-0002-0555-7727
AD  - Institute for Stem Cell Science and Regenerative Medicine (inSTEM), Bengaluru, 
      India.
AD  - Manipal Academy of Higher Education (MAHE), Madhav Nagar, Manipal, Karnataka, 
      India.
FAU - Das, Snigdhadev
AU  - Das S
AUID- ORCID: 0000-0003-0604-6862
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Mahajan, Bhagyashri
AU  - Mahajan B
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Vemula, Praveen
AU  - Vemula P
AD  - Institute for Stem Cell Science and Regenerative Medicine (inSTEM), Bengaluru, 
      India.
FAU - Bharate, Sandip B
AU  - Bharate SB
AUID- ORCID: 0000-0001-6081-5787
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Singh, Parvinder Pal
AU  - Singh PP
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Vishwakarma, Ram
AU  - Vishwakarma R
AUID- ORCID: 0000-0002-0752-6238
AD  - CSIR-Indian Institute of Integrative Medicine, Jammu, India.
FAU - Guha, Arjun
AU  - Guha A
AD  - Institute for Stem Cell Science and Regenerative Medicine (inSTEM), Bengaluru, 
      India.
FAU - Sundaramurthy, Varadharajan
AU  - Sundaramurthy V
AUID- ORCID: 0000-0003-2562-8518
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
FAU - Mayor, Satyajit
AU  - Mayor S
AUID- ORCID: 0000-0001-9842-6963
AD  - National Centre for Biological Sciences (TIFR), Bengaluru, India.
LA  - eng
GR  - WT_/Wellcome Trust/United Kingdom
GR  - IA/M/15/1/502018/WTDBT_/DBT-Wellcome Trust India Alliance/India
GR  - IA/M/15/502018/WTDBT_/DBT-Wellcome Trust India Alliance/India
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20210712
PL  - United States
TA  - PLoS Pathog
JT  - PLoS pathogens
JID - 101238921
RN  - 0 (Antiviral Agents)
RN  - 0 (Clathrin)
RN  - 0 (Macrolides)
RN  - 0 (Spike Glycoprotein, Coronavirus)
RN  - 0 (spike protein, SARS-CoV-2)
RN  - 01Q9PC255D (Ammonium Chloride)
RN  - 4QWG6N8QKH (Hydroxychloroquine)
RN  - 886U3H6UFF (Chloroquine)
RN  - 88899-55-2 (bafilomycin A1)
RN  - 8KK8CQ2K8G (Niclosamide)
RN  - EC 3.4.17.23 (ACE2 protein, human)
RN  - EC 3.4.17.23 (Angiotensin-Converting Enzyme 2)
SB  - IM
MH  - Ammonium Chloride/pharmacology
MH  - Angiotensin-Converting Enzyme 2/genetics/physiology
MH  - Animals
MH  - Antiviral Agents/administration & dosage/pharmacology
MH  - COVID-19/*virology
MH  - Cell Line
MH  - Chlorocebus aethiops
MH  - Chloroquine/pharmacology
MH  - Clathrin/metabolism
MH  - Drug Synergism
MH  - Endocytosis/drug effects/physiology
MH  - Endosomes/drug effects/metabolism
MH  - Humans
MH  - Hydrogen-Ion Concentration/drug effects
MH  - Hydroxychloroquine/administration & dosage
MH  - Macrolides/pharmacology
MH  - Niclosamide/administration & dosage/pharmacology
MH  - Protein Binding/drug effects
MH  - Protein Domains
MH  - SARS-CoV-2/*drug effects/*pathogenicity/physiology
MH  - Spike Glycoprotein, Coronavirus/chemistry/physiology
MH  - Vero Cells
MH  - Virus Internalization/*drug effects
MH  - *COVID-19 Drug Treatment
PMC - PMC8297935
COIS- The authors have declared that no competing interests exist.
EDAT- 2021/07/13 06:00
MHDA- 2021/08/06 06:00
PMCR- 2021/07/12
CRDT- 2021/07/12 17:27
PHST- 2021/05/26 00:00 [received]
PHST- 2021/06/10 00:00 [accepted]
PHST- 2021/07/22 00:00 [revised]
PHST- 2021/07/13 06:00 [pubmed]
PHST- 2021/08/06 06:00 [medline]
PHST- 2021/07/12 17:27 [entrez]
PHST- 2021/07/12 00:00 [pmc-release]
AID - PPATHOGENS-D-21-01108 [pii]
AID - 10.1371/journal.ppat.1009706 [doi]
PST - epublish
SO  - PLoS Pathog. 2021 Jul 12;17(7):e1009706. doi: 10.1371/journal.ppat.1009706. 
      eCollection 2021 Jul.