Molecular Imaging of ACE2 Expression in Infectious Disease and Cancer

Abstract

Angiotensin-converting enzyme 2 (ACE2) is a cell-surface receptor that plays a critical role in the pathogenesis of SARS-CoV-2 infection. Through the use of ligands engineered for the receptor, ACE2 imaging has emerged as a valuable tool for preclinical and clinical research. These can be used to visualize the expression and distribution of ACE2 in tissues and cells. A variety of techniques including optical, magnetic resonance, and nuclear medicine contrast agents have been developed and employed in the preclinical setting. Positron-emitting radiotracers for highly sensitive and quantitative tomography have also been translated in the context of SARS-CoV-2-infected and control patients. Together this information can be used to better understand the mechanisms of SARS-CoV-2 infection, the potential roles of ACE2 in homeostasis and disease, and to identify potential therapeutic modulators in infectious disease and cancer. This review summarizes the tools and techniques to detect and delineate ACE2 in this rapidly expanding field.

Microgliosis, astrogliosis and loss of aquaporin-4 polarity in frontal cortex of COVID-19 patients

“…Virus particles might invade into the brain through the olfactory nerve or through the choroid plexus and cause neuroinflammation (A. C. Yang et al, 2021). Angiotensin converting enzyme 2 (ACE2), the key receptor for SARS-CoV-2 entry into host cells, is highest expressed in the brain by astrocytes, although still at low levels as compared to other organs such as lungs, kidneys and heart (Li, Hasson, Daggumati, Zhang, & Thorek, 2023). In theory, thus, astrocytes could be the main target of the virus particles in the brain, causing astrogliosis and neuroinflammation.…”