To establish a better method of primary culture for alveolar epithelial type Ⅱ cells (AEC Ⅱ) and to study its bionomics, alveolar epithelial type Ⅱ cells were isolated by digestion with tryp- sin and collagenase, which were then purified by plated into culture flask coated with rat immu- noglobulin G. The purified AEC Ⅱ were identified by alkaline phosphatase staining, electron mi- croscopy, immunocytochemical staining of pulmonary surfactant protein A (SPA). The SPA expres- sion and transfection characteristics were compared with those of A549 cell line. The results showed that AEC Ⅱ could be isolated by digestion with trysin and collagenase and purified by adhesive pu- rification by using IgG, with a yield of about 2–3×107, and a purity of about 75%–84 %. Cells could be quickly identified with AKP staining. AECⅡ were different from A549 cell line in terms of SPA expression and transfection characteristics. It is concluded that adhesive purification with IgG can improve the purity of AECⅡ, and AKP staining is simple in cell identification. AECⅡ can not be completely replaced by A549 cells in some studies because the differences between them, such as SPA expression.
