Objective:Todevelop the isolation and purification technology for typeⅡalveolar epithelial cells(AECⅡ)of fetal rat

in order to provide experimental means for the study of lung development or neonatal lung disease.Methods:Lung tissues of 19-day fetal rats were digested with trypsin and collagenase

then purified for AECⅡwith different centrifugal force and repeated attachment.Cell viability was evaluated by typran inclusion dying before plated into six-well flask.Growth status and shape of attached cells were observed with inverted phase contrast microscope.AECⅡwere identified by electron microscopy and its percentage was assessed by modified Papanicolaou dying and immunofluorescence

the latter aiming to detect expression of surfactant protein C(SPC)in AECⅡ.Results:The total amount of cells we harvested from 3 to5 fetal rat was(36±5)×106 with a viability of 98%±2%.Cells were like polygonal and connected like island under microscope.AECⅡwas ascertained by lamellar bodies found in cytoplasma under electron microscope and its percentage was 96%±3%identified by modified Papanicolaou dying

the same as the result by immunofluorescence for SPC.Conclusion:Highly Purified and viable AECⅡcould be achieved by our methods and the cell model could be used in further study.