Immunocytochemical Assessment of ACE2 and TMPRSS2 in Nasopharyngeal Swabs from SARS-CoV-2 Patients

Karla Beatríz Peña; Josep Gumà; Carmen Guilarte; Lola Delamo; Marc Grifol; Berta Pique; Anna Hernandez; Helena Casteñé; Francesc Riu; David Parada

doi:10.31083/j.fbl2707217

Frontiers in Bioscience-Landmark (Jul 2022)

Immunocytochemical Assessment of ACE2 and TMPRSS2 in Nasopharyngeal Swabs from SARS-CoV-2 Patients

Karla Beatríz Peña,
Josep Gumà,
Carmen Guilarte,
Lola Delamo,
Marc Grifol,
Berta Pique,
Anna Hernandez,
Helena Casteñé,
Francesc Riu,
David Parada

Affiliations

Karla Beatríz Peña: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Josep Gumà: Department of Oncology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Carmen Guilarte: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Lola Delamo: Department of Oncology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Marc Grifol: Department of Oncology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Berta Pique: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Anna Hernandez: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
Helena Casteñé: Reserca Biomedical Unit, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43202 Reus (Tarragona), Spain
Francesc Riu: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain
David Parada: Pathology Molecular Unit, Department of Pathology, Sant Joan University Hospital, Pere Virgili Health Research Institute, Faculty of Medicine, Rovira and Virgili University, 43204 Reus (Tarragona), Spain

DOI: https://doi.org/10.31083/j.fbl2707217
Journal volume & issue: Vol. 27, no. 7
p. 217

Abstract

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Background: SARS-CoV-2 is a positive-sense single-stranded RNA virus. It is enveloped by four structural proteins. The entry of the virus into the host cells is mediated by spike protein binding to the angiotensin converting enzyme 2 (ACE2) and proteolytic cleavage by transmembrane protease serine 2 (TMPRSS2). In this study, we analyzed the expression of the ACE2 receptor and TMPRSS2 in cases under investigation for SARS-CoV-2 infection. Methods: The study was carried out using the viral transport medium of consecutive nasopharyngeal swabs from 300 people under examination for SARS-CoV-2 infection. All samples underwent the SARS-CoV-2 transcriptase-mediated amplification assay (Procleix® SARS-CoV-2) to detect the virus. Immunocytochemistry was used in each sample to detect the presence of the SARS-CoV-2 nucleoprotein, the ACE2 receptor, and TMPRSS2. Results: An immunocytochemical study with monoclonal antibody against SARS-CoV-2 viral nucleoprotein showed positivity in squamous cells. ACE2 were not detected in the squamous cells obtained from the nasopharyngeal samples. Conclusions: SARS-CoV-2 predominantly localizes to squamous cells in cytology samples of patients with positive transcriptase-mediated amplification SARS-CoV-2 assay results. The immunocytochemical negativity for ACE2 evidenced in the present study could be related to the cellular heterogeneity present in the nasopharyngeal smear samples and could be related to variations at the genomic level. Our results suggest that SARS-CoV-2 might be present in the nasopharyngeal region because viral cell junctions are weaker. This facilitates viral concentration, infective capacity and migration to specific organs, where SARS-CoV-2 infects target cells by binding to their receptors and then entering.

Published in Frontiers in Bioscience-Landmark

ISSN: 2768-6701 (Print); 2768-6698 (Online)
Publisher: IMR Press
Country of publisher: Singapore
LCC subjects: Science: Chemistry: Organic chemistry: Biochemistry; Science: Biology (General)
Website: https://www.imrpress.com/journal/FBL

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