CD47 and viral infectious disease: Given that epithelial CD47 was exclusively induced in ciliated cells during viral infection (Supplementary Fig. 2d, Fig. 1e), we generated mice with selective CD47 loss in ciliated cells by creating CD47 floxed mice (CD47f/f), bred to constitutively express Cre under the control of the Foxj1 promoter (Foxj1Cre)48.