THE GRANULOCYTE-COLONY-STIMULATING FACTOR PRODUCED IN THE HUMAN LUNG AND ITS EFFECT ON LIQUID MOVEMENT IN THE RABBIT LUNG

Levels of the granulocyte colony-stimulating factor (G-CSF) were deter mined in the plasma and resected lung tissue from patients who underwe nt pulmonary resection. Moreover, the effect of recombinant human (rh) G-CSF on the permeability of pulmonary endothelium and on liquid clea rance from the alveolar spaces was investigated in rabbits. The plasma levels of G-CSF increased from 30 pg/ml preoperatively to 409 +/- 236 pg/ml 3 h postoperatively (P < 0.05), while the levels of G-CSF in th e resected lung tissue were increased in the alveolar fluid, to 1,834 +/- 1,054 pg/ml, and in the pulmonary blood, to 5,466 +/- 2,019 pg/ml. It was found that rh G-CSF 25 mu g administered into the subcutaneous tissue of rabbits increased extravascular lung water to 3.45 +/- 0.26 vs 2.98 +/- 0.20 in control experiments (P < 0.05); however, rhG-CSF 0.75 mu g/kg administered into the alveloar spaces did not affect liqu id clearance from the alveolar spaces. The findings of this study led us to conclude that G-CSF is synthesized in the human lung and increas es the permeability of pulmonary endothelium, but not liquid clearance across the alveolar epithelium.