Cell type

Cell biology

Biology

Receptor

Environmental health

Genetics

Angiotensin II

Population

Internal medicine

Angiotensin II receptor type 1

Medicine

Cell

Lung

Proceedings of the National Academy of Sciences

Significance Pulmonary alveolar type I (AT1) cells are essential for the gas-exchange function of lungs. AT1 cells retain their cellular plasticity during injury-induced alveolar regeneration. However, we know very little about the developmental heterogeneity of the AT1 cell population. Our study identified a robust genetic marker of postnatal AT1 cells, insulin-like growth factor-binding protein 2 (Igfbp2). We use this marker to demonstrate that the postnatal AT1 cell population actually consists of two AT1 cell subtypes (Hopx + Igfbp2 + and Hopx + Igfbp2 − AT1 cells) with distinct cell fates during alveolar regeneration. The large majority of adult AT1 cells expresses Igfbp2 and cannot transdifferentiate into AT2 cells during post pneumonectomy formation of new alveoli. Therefore, Hopx + Igfbp2 + AT1 cells represent the terminally differentiated population of AT1 cells.

Pulmonary alveolar type I cell population consists of two distinct subtypes that differ in cell fate