MLE-12 Cells

MLE-12 is a murine lung epithelial cell line established from distal respiratory epithelium using transgenic mice expressing the simian virus 40 (SV40) large tumor antigen under the control of the human surfactant protein C (SP-C) promoter. This cell line is characterized by its ability to maintain certain properties of alveolar type II cells, such as the expression of surfactant proteins SP-B and SP-C, which are crucial for pulmonary surfactant synthesis and lung function. MLE-12 cells also display key morphological features of alveolar type II cells, including microvilli and multivesicular bodies, though they lack some features like lamellar bodies in later passages. The MLE-12 cell line is widely used to study surfactant protein regulation, secretion, and pulmonary responses to stimuli. It secretes phospholipids in response to various secretagogues such as ATP and phorbol esters, mimicking aspects of type II alveolar cell function. While this secretion is robust in early passages, it diminishes in later passages, along with changes in receptor-mediated responses. This model is particularly valuable for exploring mechanisms underlying respiratory distress syndromes and surfactant deficiencies. Additionally, the cell line offers insights into pulmonary carcinogenesis, given its derivation from SV40-driven tumorigenesis. MLE-12 cells serve as a tool for elucidating the pathways of surfactant protein processing and testing therapeutic strategies for surfactant replacement. Their maintenance of SP-C expression, a marker specific to the alveolar epithelium, makes them a relevant in vitro model for investigating lung-specific processes and diseases.