MLE-12

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.

37°C, 5% CO₂, humidified atmosphere.

1. Confirm that the vial remains deeply frozen upon delivery, as cells are shipped on dry ice to maintain optimal temperatures during transit.

2. Upon receipt, either store the cryovial immediately at temperatures below -150°C to ensure the preservation of cellular integrity, or proceed to step 3 if immediate culturing is required.

3. For immediate culturing, swiftly thaw the vial by immersing it in a 37°C water bath with clean water and an antimicrobial agent, agitating gently for 40-60 seconds until a small ice clump remains.

4. Perform all subsequent steps under sterile conditions in a flow hood, disinfecting the cryovial with 70% ethanol before opening.

5. Carefully open the disinfected vial and transfer the cell suspension into a 15 ml centrifuge tube containing 8 ml of room-temperature culture medium, mixing gently.

6. Centrifuge the mixture at 300 x g for 3 minutes to separate the cells and carefully discard the supernatant containing residual freezing medium.

7. Gently resuspend the cell pellet in 10 ml of fresh culture medium. For adherent cells, divide the suspension between two T25 culture flasks; for suspension cultures, transfer all the medium into one T25 flask to promote effective cell interaction and growth.

8. Adhere to established subculture protocols for continued growth and maintenance of the cell line, ensuring reliable experimental outcomes.

Mycoplasma contamination is excluded using both PCR-based assays and luminescence-based mycoplasma detection methods.

To ensure there is no bacterial, fungal, or yeast contamination, cell cultures are subjected to daily visual inspections.

For long-term preservation, place vials in vapor-phase liquid nitrogen at about −150 to −196 °C. Storage at −80 °C is acceptable only as a short interim step before transfer to liquid nitrogen.

Cryopreserved cell lines are shipped on dry ice in validated, insulated packaging with sufficient refrigerant to maintain approximately −78 °C throughout transit. On receipt, inspect the container immediately and transfer vials without delay to appropriate storage.

At Cytion, we stand behind the quality and viability of our products. We guarantee that our cells will be viable at the start of culture for 60 days after shipment from our facilities. We assure that all materials conform to the specifications described in the Certificate of Analysis and/or Product Sheet.

For full details, please refer to our Warranty Statement.