TTR and COVID-19: In all 4 assessed COVID-19 tissues, SARS-CoV-2 S transcripts were observed in 20–30% of cells per image, from which the majority corresponded to TTR+ ChP epithelial cells, except in one patient (P3) in which an equal number of not further defined stromal cells were SARS-CoV-2 S+ (Fig. 6A-B and Fig. S3, Additional file 1).