Journal Article

Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues

Wang, Xiao-Sheng, Li, Lin, Li, Meng-Yuan, Zhang, Yue

2020

Overview

Background Since its discovery in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 2 180 000 people worldwide and has caused more than 150 000 deaths as of April 16, 2020. SARS-CoV-2, which is the virus causing coronavirus disease 2019 (COVID-19), uses the angiotensin-converting enzyme 2 (ACE2) as a cell receptor to invade human cells. Thus, ACE2 is the key to understanding the mechanism of SARS-CoV-2 infection. This study is to investigate the ACE2 expression in various human tissues in order to provide insights into the mechanism of SARS-CoV-2 infection. Methods We compared ACE2 expression levels across 31 normal human tissues between males and females and between younger (ages ≤ 49 years) and older (ages > 49 years) persons using two-sided Student’s t test. We also investigated the correlations between ACE2 expression and immune signatures in various tissues using Pearson’s correlation test. Results ACE2 expression levels were the highest in the small intestine, testis, kidneys, heart, thyroid, and adipose tissue, and were the lowest in the blood, spleen, bone marrow, brain, blood vessels, and muscle. ACE2 showed medium expression levels in the lungs, colon, liver, bladder, and adrenal gland. ACE2 was not differentially expressed between males and females or between younger and older persons in any tissue. In the skin, digestive system, brain, and blood vessels, ACE2 expression levels were positively associated with immune signatures in both males and females. In the thyroid and lungs, ACE2 expression levels were positively and negatively associated with immune signatures in males and females, respectively, and in the lungs they had a positive and a negative correlation in the older and younger groups, respectively. Conclusions Our data indicate that SARS-CoV-2 may infect other tissues aside from the lungs and infect persons with different sexes, ages, and races equally. The different host immune responses to SARS-CoV-2 infection may partially explain why males and females, young and old persons infected with this virus have markedly distinct disease severity. This study provides new insights into the role of ACE2 in the SARS-CoV-2 pandemic.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Adipose tissue / Adrenal glands / Adult / Age Factors / Aged / Angiotensin-Converting Enzyme 2 / Angiotensins / Betacoronavirus / Bone marrow / Brain - enzymology / Cancer / Cardiovascular System - enzymology / Cardiovascular System - immunology / Cells (Biology) / Colon / Comparative analysis / Coronaviruses / COVID-19 / Datasets / Digestive system / Digestive System - enzymology / Digestive System - immunology / Disease transmission / Elderly / Endocrine Glands - enzymology / Endocrine Glands - immunology / Enzymes / Esophagus / Female / Gallbladder / Gene expression / Gene Expression Profiling / Genetic research / Health aspects / Humans / Immune System - enzymology / Infections / Infectious Diseases / Interferons - immunology / Kidneys / Liver / Lung - enzymology / Lung - immunology / Lungs / Lymphocytes / Lymphocytes - immunology / Male / Males / Medical research / Medicine / Medicine & Public Health / Middle Aged / Older people / Organ Specificity / Pancreas / Pandemics / Peptidyl-Dipeptidase A - blood / Peptidyl-Dipeptidase A - genetics / Pneumonia / Proteins / Public Health / Receptors, Coronavirus / Receptors, Virus - blood / Receptors, Virus - genetics / Research Article / RNA-Seq / SARS-CoV-2 / SARS-CoV-2 cell receptor / SARS-CoV-2 pandemic / Severe acute respiratory syndrome / Severe acute respiratory syndrome coronavirus 2 / Sex Factors / Skin / Small intestine / Thyroid / Thyroid gland / Transmission patterns and control of COVID-19 epidemic / Tropical Medicine / Urogenital System - enzymology