ACE2 and COVID-19: Angiotensin-converting enzyme 2 expression in the lung is upregulated on SARS-CoV-2 infection, with type 2 pneumocytes potentially serving as a key cell type facilitating pulmonary inflammation (Drucker, 2020); notably, interleukin IL-6 may be further exaggerated in response to a stimulus as seen in diabetic patients with COVID-19 (Chan-Yeung and Xu, 2003).