BMI1 Transduction of Human Airway Epithelial Cells for Expansion of Proliferation and Differentiation.

Air-liquid interface (ALI)-cultured cells are widely used as in vitro models of the human respiratory airway in studies of pulmonary physiology, disease, and therapies. However, the primary basal cells required to establish the ALI cultures generally lose their ability to differentiate by the second or third passage, requiring a fresh batch, which can be limiting, particularly from donors with rare genotypes or in studies where gene modification or editing is required. We have developed a method that preserves the ability to expand primary cells and maintain their capacity to differentiate by lentiviral transduction with BMI1. BMI1-transduced basal airway cells are maintained in submerged culture in the same way as primary basal cells but can be passaged more than 20 times retaining their differentiation capacity in ALI cultures. BMI1-transduced basal cells can be frozen and stored long term in liquid nitrogen, enabling transfer of samples between research groups.