S100A4 and idiopathic pulmonary fibrosis: These findings parallel the cytoplasmic S100A4-NMII-A interaction seen in stage-specific embryonic antigen-4 (SSEA4+) stem cells from lungs of patients with IPF after 21 days using standard tissue culture conditions, although spontaneous cell motility, rather than myofibroblast differentiation, was enhanced under those conditions (67).