VIM and posterior cortical atrophy: The mesenchymal origin of the stromal cell cultures was further confirmed by western blot analyses, where, in contrast to PCa PC346C cells, the PCDF cells stained positive for the mesenchymal markers Vimentin and PDGFRβ, which was shared with the human telomerase‐immortalized foreskin fibroblast hTERT‐BJ1 (Fig. 3B).