Fig. 2: SARS-CoV-2 receptors are expressed in the human pancreas.

a Pancreas sections from COVID-19 patients were immunostained for insulin to mark beta-cells. Additionally, double stainings for ACE2 and TMPRSS2 were performed. Representative images from three independent experiments (n = 3) are shown. Islets are indicated. Scale bars, 100 µm. b Triple immunostaining for ACE2, insulin and the endothelial marker VCAM-1. Representative image from two independent experiments (n = 2) are shown. Islets are indicated. Scale bar, 100 µm. c Dot blot showing the percentage of beta-cells positive for ACE2 in control and COVID-19 patients. All insulin-positive cells in n ≥ 3 islets per patient were counted from three independent experiments (n = 3). Data were analyzed by unpaired two-sided t-test by comparison with Ctrl #3. Data are presented as mean ± SD. d Morphometric analysis of an ACE2/Insulin/SARS-CoV-2-N staining of pancreatic tissue from COVID-19 patient #2 (n = 1). The fluorescence intensities in the indicated fluorescence channels along the white line were measured. Scale bar, 100 µm. e Calculated total cellular fluorescence (CTCF) of SARS-CoV-2 in insulin-positive and -negative islet cells, exocrine cells, and endothelial cells. Data were analyzed by unpaired two-sided t-test by comparison with Ctrl #3. Data are presented as mean ± SD. f CTCF of ACE2 and SARS-CoV-2 was calculated in insulin-positive and -negative islet cells, exocrine cells and endothelial cells. Data were analyzed by two-way ANOVA and Bonferroni posttest. Data are presented as mean ± SD. *p < 0.05; **p < 0.01; ***p < 0.001. In e and f, quantification of CTCF was calculated based on n ≥ 5 cells from n ≥ 2 islets per patient from one (n = 1) out of three independent experiments.