Fig 1: TBX2+ cells contribute to fibroblasts, endothelial, mesothelial and SM cells in the developing lung. (a) Double immunofluorescence analysis of the lineage marker GFP and the epithelial marker CDH1 on transversal (E9.5) and frontal (E10.5 and older) sections of Tbx2cre/+;R26mTmG/+ lungs. (b) Double immunofluorescence of the lineage marker GFP and marker proteins of SMCs (ACTA2, TAGLN), the endothelium (EMCN, KDR), the visceral pleura (ALDH1A2, WT1), different types of fibroblasts and ECM (POSTN, S100A4, PDGFRA, PDGFRB) on frontal lung sections of Tbx2cre/+;R26mTmG/+ embryos at representative stages. (c) Quantification of GFP signal reflecting the lineage contribution to the mesenchyme of the whole lung (E10.5 and E12.5) and the right lung lobe (E14.5, E16.5). Average values: E10.5: 88% ± 7%; E12.5: 103% ± 13%; E14.5: 98 ± 2%, E16.5: 102% ± 2%. (d) Quantification of GFP expression in specific cell-types at E14.5 and E16.5. Average values: ACTA2+: 98% ± 6%; TAGLN+: 97% ± 2%; EMCN+: 101 ± 18%; ALDH1A2+: 58% ± 10%; POSTN+: 91 ± 11%; PDGFRA+: 79% ± 5%; PDGFRB+: 47% ± 9%. The complete data set is provided in Table S1. Values above 100% are technical artefacts. Antigens are color-coded, stages are as indicated. Nuclei were counterstained with DAPI. Insets or selected regions of overview images are magnified in the row below. ca: caudal; cr: cranial; d: dorsal; f: foregut; l: left; lb.: lung bud; r: right; v: ventral. Arrowhead: indicates an auto-fluorescent cell