To begin, arrange freshly prepared expansion medium, filter sterilized proteinase and antibiotic solutions, and sterilized surgical instruments on the working platform of the biosafety cabinet. Add rat tail collagen into 100-millimeter culture dishes and 24-millimeter trans wells. Leave the dishes open overnight under ultraviolet light for sterilization.
Immerse the euthanized mouse in 75%ethanol for sterilization. Do not immerse the nose and mouth. Using surgical scissors and forceps, cut and open the epidermis from the lower jaw to the abdominal cavity of the mouse.
Using another set of surgical scissors and forceps, tear apart the thyroid glands on both sides and remove the connections between the trachea, the surrounding muscle tissue, and the esophagus. Next, carefully cut into the chest, and use forceps to delve deeper into the chest cavity. Remove the entire lung and find the end of the trachea.
Cut out the trachea from the thyroid cartilage to the tracheal bronchial branch, and put it in a pre cold expansion medium containing four antibiotics. Shake the tube to rinse as much blood as possible off the surface of the trachea before placing it on ice. Now transfer the trachea to pre cold PBS containing four antibiotics.
Using surgical scissors and forceps, remove clots and other tissue from the surface of the trachea and cut them into one square centimeter size. Incubate tracheal tissue in proteinase solution at 37 degrees Celsius. After 40 minutes, rock the tube several times and use a 40-micron cell strainer to remove the remaining tissues.
Rinse the chopped trachea on a strainer with five milliliters of expansion medium. Centrifuge the tracheal suspension at 400 G for five minutes at four degrees Celsius, and resuspend the pellet in eight milliliters of expansion medium. Count the viable cells using trypan blue and the hemocytometer.
Plate P0 cell suspension on a 100-millimeter dish, precoated with rat tail collagen. Culture the cells at 37 degrees Celsius with 5%carbon dioxide.
