Schmiedl, A.A.SchmiedlLempa, T.T.LempaHoymann, H.G.H.G.HoymannRittinghausen, S.S.RittinghausenPopa, D.D.PopaTschernig, T.T.TschernigFehrenbach, H.H.FehrenbachPabst, R.R.PabstHoeper, M.M.M.M.HoeperHohlfeld, J.M.J.M.Hohlfeld2022-03-042022-03-042008https://publica.fraunhofer.de/handle/publica/21582110.1007/s00428-008-0591-z2-s2.0-44449164315We hypothesized that formation of pulmonary emphysema could be diminished after previous activation of stem cells. Animals received either a daily dose of the hematopoietic growth factors (GF; recombinant rat stem cell factor plus recombinant granulocyte colony stimulating factor; n= 6, Elastase/ GF group) or vehicle ( n= 9, Elastase/ Sham group) starting 3 days before intratracheal instillation of elastase or vehicle and continued for another 25 days. Control animals were treated with NaCl ( n= 9, Sham/ Sham group). On day 25, in all animals, a 2-mL pump was implanted subcutaneously that delivered 200 mu g/ h 5-bromo2- desoxyuridine ( BrdU) until study termination. Compared to controls, the Elastase/ Sham group exhibited elevated total lung capacity (TLC) and functional residual capacity (FRC), significantly increased mean free alveolar pathway, alveolar volume, and decreased septal density. The Elastase/ GF group showed ( 1) a significant increase of TLC and FRC, ( 2) a significant increase in alveolar size and volume, ( 3) a significant reduction of septal density, volume, and thickness. Proliferation in lung parenchyma and in terminal bronchioles remained significantly decreased in the Elastase/ Sham group and the Elastase/ GF group. Blood cell number has significantly increased in the Elastase/ GF group. The application of GF-enhanced pulmonary emphysema, presumable because of increased inflammatory activity, was a result of a preventive treatment.enlung emphysemastem cell factorlung functionratstereology610571journal article