CHRNA7 and pneumonia: Since d3 BM-MNCs were enriched with α7nAChR+Sca1+ cells, we isolated BM-MNCs (106 cells) from d3 pneumonia and normal mice and transplanted these cells (106 cells) into the lungs of recipient mice 4 h after E. coli challenge (2.5 × 106 CFU) in combination with or without PHA568487 (α7nAChR agonist).