Angiotensin-Converting Enzyme 2 Expression Is Detectable in Keratinocytes, Cutaneous Appendages, and Blood Vessels by Multiplex RNA In Situ Hybridization.

Objective: The angiotensin-converting enzyme 2 (ACE2) receptor mediates uptake of SARS-CoV-2, the virus responsible for COVID-19. Previous work analyzing publicly available bulk RNA-sequencing data sets has shown the expression of ACE2 in human keratinocytes. This finding is potentially relevant for the etiology of COVID-19-associated rashes and might also suggest a possible entry mechanism for the SARS-CoV-2 virus. In this study, the authors examined the spatial localization of ACE2 mRNA in vivo.

Methods And Results: The authors analyzed several publicly available single-cell RNA-sequencing data sets. They determined spatial localization of ACE2 mRNA using multiplex RNA in situ hybridization in human skin.

Conclusions: Both analyses supported ACE2 expression in keratinocytes and skin vasculature, which could reflect a potential cutaneous entry point for SARS-CoV-2, particularly in damaged or broken skin. Moreover, ACE2 expression in vascular endothelial cells may support direct, virally mediated mechanisms in the etiology of the chilblain-like acral eruption that is seen in patients with COVID-19.