In this study, we report the isolation and identification of previously undocumented stem/progenitor epithelial cells from bone marrow of pigs. These cells expressed the stem/progenitor cell markers Oct4, SSEA-1, and Ccsp, and the epithelial markers Pan-K, K-18, and occludin. Upon culture in epithelial differentiation media, these cells differentiated into type I and II pneumocytes. Most importantly, progenitor cells were targets for mammalian and avian influenza virus replication.