Fig. 6.

SARS-CoV-2 infection aggregated activation of α-SMA and accumulation of collagen fibers in the human pancreas. a Pancreatic tissue sections from deceased control subject were stained by multi-label immunofluorescence (IF) for COL1A1 (CL, yellow), α-SMA (α, red), Ki67 (K, magenta), SARS-CoV-2 S1 protein (S, cyan), insulin (β, green), and CD31 (CD, white). Scale bars, 800 μm. b Pancreatic tissue sections from the prototypic SARS-CoV-2 strain-infected COVID-19 autopsy samples were stained by multi-label immunofluorescence (IF) for COL1A1 (CL, yellow), α-SMA (α, red), Ki67 (K, magenta), SARS-CoV-2 S1 protein (S, cyan), insulin (β, green), and CD31 (CD, white). Scale bars, 800 μm. c–e Representative multi-label IF image from the magnified section of (a). Inset highlights activation of α-SMA and proliferation of collagen fibers in both the exocrine and endocrine pancreatic tissues. Scale bars, 50 μm. f–i Quantification of the percentage of COL1A1⁺, α-SMA⁺, Ki67⁺, and CD31⁺ cells, as well as insulin⁺COL1A1⁺, insulin⁺ α-SMA⁺, and S protein⁺ CD31⁺ cells, in the control human pancreatic tissues and the COVID-19 patients pancreatic tissues (n = 10 images/group). Data are presented as mean ± SD. p values were calculated by unpaired two-tailed Student’s t test. *p < 0.05, **p < 0.01, and ***p < 0.001