Freshly harvested lungs from C57BL/6J mice were enzymatically dissociated with 5mg/ml Dispase in PBS/2%FBS in room temperature for 1 hour, tissues were minced, then were incubated on the shaker (100rpm) with 50 µg/ml DNase I for 30 min. Cell suspension was washed and filtered with 70 µm strainers. Cells were labeled with VE-cadherin-PE and CD45-FTIC antibodies, VE-cadherin+ and CD45- cells were sorted by fluorescence-activated cell sorting (FACS) for scRNA-seq analysis. scRNA libraries were constructed according to the manufacturer's instructions (single cell 3' v3 protocol, 10x Genomics).