ACE2 and TMPRSS2 Immunolocalization and COVID-19-Related Thyroid Disorder
Gi-Cheol Park,
Hyoun-Wook Lee,
Ji-Min Kim,
Ji-Min Han,
Hye-In Kim,
Sung-Chan Shin,
Yong-il Cheon,
Eui-Suk Sung,
Minhyung Lee,
Jin-Choon Lee,
Dong-Min Shin,
Byung-Joo Lee
Affiliations
Gi-Cheol Park
Department of Otolaryngology—Head and Neck Surgery, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea
Hyoun-Wook Lee
Department of Pathology, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea
Ji-Min Kim
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Busan 49241, Korea
Ji-Min Han
Department of Medicine, Division of Endocrinology and Metabolism, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea
Hye-In Kim
Department of Medicine, Division of Endocrinology and Metabolism, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea
Sung-Chan Shin
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Busan 49241, Korea
Yong-il Cheon
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Busan 49241, Korea
Eui-Suk Sung
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Yangsan Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Yangsan 50612, Korea
Minhyung Lee
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Yangsan Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Yangsan 50612, Korea
Jin-Choon Lee
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Yangsan Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Yangsan 50612, Korea
Dong-Min Shin
Department of Otolaryngology—Head and Neck Surgery, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon 51353, Korea
Byung-Joo Lee
Department of Otorhinolaryngology—Head and Neck Surgery, Pusan National University Hospital, Biomedical Research Institute, College of Medicine, Pusan National University, Busan 49241, Korea
Thyroid dysfunction has been reported to be an extrapulmonary symptom of COVID-19. It is important to identify the tissue subset that expresses angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2), which are essential for host infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in order to understand the viral pathogenesis of COVID-19-related thyroid dysfunction. We investigated the expression and distribution of ACE2- and TMPRSS2-expressing cells in the thyroid gland. RT-PCR and Western blotting were performed on human thyroid follicular cells (Nthy-ori3-1) and rat thyroid tissues to detect the expression levels of ACE and TMPRSS2 mRNA and proteins. We also analyzed the expression patterns of ACE2 and TMPRSS2 in 9 Sprague-Dawley rats and 15 human thyroid tissues, including 5 normal, 5 with Hashimoto’s thyroiditis, and 5 with Graves’ disease, by immunohistochemistry (IHC) and immunofluorescence. Both ACE2 and TMPRSS2 mRNAs and proteins were detected in the thyroid tissue. However, ACE2 and TMPRSS2 proteins were not expressed in thyroid follicular cells. In IHC, ACE2 and TMPRSS2 were not stained in the follicular cells. No cells co-expressed ACE2 and TMPRSS2. ACE2 was expressed in pericytes between follicles, and TMPRSS2 was mainly stained in the colloid inside the follicle. There was no difference in expression between the normal thyroid, Hashimoto’s thyroiditis, and Graves’ disease. SARS-CoV-2 does not directly invade the thyroid follicular cells. Whether SARS-CoV-2 infection of pericytes can affect COVID-19-related thyroid dysfunction warrants further study.
