Expression Profile of SARS-CoV-2 Host Receptors in Human Pancreatic Islets Revealed Upregulation of in Diabetic Donors.

Cellular entry of SARS-CoV-2 is thought to occur through the binding of viral spike S1 protein to . The entry process involves priming of the S protein by and , which collectively mediate the binding and promote ACE2 shedding. In this study, microarray and RNA-sequencing (RNA-seq) expression data were utilized to profile the expression pattern of , , and in type 2 diabetic (T2D) and non-diabetic human pancreatic islets. Our data show that pancreatic islets express all three receptors irrespective of diabetes status. The expression of was significantly increased in diabetic/hyperglycemic islets compared to non-diabetic/normoglycemic. Islets from female donors showed higher expression compared to males; the expression of and was not affected by gender. The expression of the three receptors was statistically similar in young (≤40 years old) versus old (≥60 years old) donors. Obese (BMI > 30) donors have significantly higher expression levels of and relative to those from non-obese donors (BMI < 25). expression correlated positively with HbA1c and negatively with age, while and correlated positively with BMI. The expression of the three receptors was statistically similar in muscle and subcutaneous adipose tissues obtained from diabetic and nondiabetic donors. Lastly, expression was higher in sorted pancreatic β-cell relative to other endocrine cells. In conclusion, expression is increased in diabetic human islets. More studies are required to investigate whether variations of expression could explain the severity of COVID-19 infection-related symptoms between diabetics and non-diabetic patients.