The study presents a comprehensive analysis of ACE2 protein expression across >150 cell types in human tissues using immunohistochemistry and compares it with transcriptomics and other proteomic data. ACE2, the receptor for SARS-CoV-2, is mainly expressed in enterocytes, renal tubules, gallbladder, cardiomyocytes, male reproductive cells, placental trophoblasts, ductal cells, eye, and vasculature. In the respiratory system, ACE2 expression is limited, with only low or no expression in most cells. The study confirms high ACE2 expression in the intestinal tract, kidney, testis, gallbladder, and heart, but low or absent expression in the lung. ACE2 is also expressed in the eye, with high levels in the conjunctiva and cornea. The study highlights the importance of ACE2 in SARS-CoV-2 entry into host cells and its role in disease progression. However, the protein expression in the respiratory tract is limited, with no or low expression in most cells. The study also shows that ACE2 is expressed in various other tissues, including the placenta, fallopian tube, and thyroid. The results suggest that ACE2 expression is not uniformly distributed across all tissues and that the expression levels vary significantly between different cell types and tissues. The study provides a detailed map of ACE2 expression in human tissues, which can be used to understand the biology of SARS-CoV-2 infection and to develop effective treatments for the disease. The study also highlights the importance of further research to confirm the expression of ACE2 in the respiratory tract and to understand the role of ACE2 in the pathogenesis of SARS-CoV-2. The study is an important resource for further research on SARS-CoV-2 host cell entry and the development of effective treatments for the disease.The study presents a comprehensive analysis of ACE2 protein expression across >150 cell types in human tissues using immunohistochemistry and compares it with transcriptomics and other proteomic data. ACE2, the receptor for SARS-CoV-2, is mainly expressed in enterocytes, renal tubules, gallbladder, cardiomyocytes, male reproductive cells, placental trophoblasts, ductal cells, eye, and vasculature. In the respiratory system, ACE2 expression is limited, with only low or no expression in most cells. The study confirms high ACE2 expression in the intestinal tract, kidney, testis, gallbladder, and heart, but low or absent expression in the lung. ACE2 is also expressed in the eye, with high levels in the conjunctiva and cornea. The study highlights the importance of ACE2 in SARS-CoV-2 entry into host cells and its role in disease progression. However, the protein expression in the respiratory tract is limited, with no or low expression in most cells. The study also shows that ACE2 is expressed in various other tissues, including the placenta, fallopian tube, and thyroid. The results suggest that ACE2 expression is not uniformly distributed across all tissues and that the expression levels vary significantly between different cell types and tissues. The study provides a detailed map of ACE2 expression in human tissues, which can be used to understand the biology of SARS-CoV-2 infection and to develop effective treatments for the disease. The study also highlights the importance of further research to confirm the expression of ACE2 in the respiratory tract and to understand the role of ACE2 in the pathogenesis of SARS-CoV-2. The study is an important resource for further research on SARS-CoV-2 host cell entry and the development of effective treatments for the disease.