Deep sequencing of primary human lung epithelial cells challenged with H5N1 influenza virus reveals a proviral role for CEACAM1

Siying Ye; Chris Cowled; Cheng-Hon Yap; John Stambas

The molecular mechanism of CEACAM1 action following infection has also been explored in 342 A549 cells using the low pathogenic PR8 virus (51) (18) and 359 papillomavirus (19), it will be important to determine whether a common mechanism of action can be 360 attributed to CEACAM1 in order to determine its functional significance. If this can be established, 361 CEACAM1 could be used as a target for the development of a pan-antiviral agent. Furthermore, it has 362 been shown that CEACAM1-S isoforms and soluble isoforms (CEACAM1-4C1, -3, -3C2) also have 363 regulatory effects (stimulatory or inhibitory) on CEACAM1-L isoforms (20, 52). Although 364 CEACAM1-Ls are the dominate isoforms, the involvement of other CEACAM1 isoforms in influenza 365 immunity should also be further investigated, especially as H5N1 infection increased mRNA 366 expression levels of several CEACAM1 variants (Fig. 3C) . 367