Biomedical Informatics Research Lab, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 211198, China.
Big Data Research Institute, China Pharmaceutical University, Nanjing, 211198, China.
Infect Dis Poverty. 2020 Apr 28;9(1):45. doi: 10.1186/s40249-020-00662-x.
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.
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.
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.
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.
自 2019 年 12 月发现以来，严重急性呼吸系统综合症冠状病毒 2（SARS-CoV-2）已在全球范围内感染了超过 21.8 万人，并导致截至 2020 年 4 月 16 日超过 15 万人死亡。SARS-CoV-2 是导致 2019 年冠状病毒病（COVID-19）的病毒，它使用血管紧张素转换酶 2（ACE2）作为细胞受体来侵入人体细胞。因此，ACE2 是了解 SARS-CoV-2 感染机制的关键。本研究旨在调查各种人体组织中的 ACE2 表达水平，以深入了解 SARS-CoV-2 感染的机制。
我们使用双侧学生 t 检验比较了男性和女性以及年龄≤49 岁和>49 岁的个体之间 31 种正常人体组织中 ACE2 的表达水平。我们还使用 Pearson 相关检验调查了各种组织中 ACE2 表达与免疫特征之间的相关性。
ACE2 的表达水平在小肠、睾丸、肾脏、心脏、甲状腺和脂肪组织中最高，在血液、脾脏、骨髓、大脑、血管和肌肉中最低。ACE2 在肺部、结肠、肝脏、膀胱和肾上腺中的表达水平中等。在任何组织中，ACE2 在男性和女性之间或在年轻和年长个体之间均无差异表达。在皮肤、消化系统、大脑和血管中，ACE2 的表达水平与男性和女性的免疫特征呈正相关。在甲状腺和肺部中，ACE2 的表达水平与男性和女性的免疫特征呈正相关和负相关，而在肺部中，在年长和年轻组中分别呈正相关和负相关。
我们的数据表明，SARS-CoV-2 可能感染肺部以外的其他组织，并平等感染不同性别、年龄和种族的个体。不同宿主对 SARS-CoV-2 感染的免疫反应可能部分解释了为什么感染这种病毒的男性和女性、年轻和年长个体的疾病严重程度有显著差异。本研究为 ACE2 在 SARS-CoV-2 大流行中的作用提供了新的见解。
