6ArrayExpress Uploader0mouseEGFP-positiveEGFP-positiveEGFP-positiveEGFP-negativeEGFP-negativeEGFP-negative6290arrayexpress_sidhttp://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-25778Pulmonary alveoli contain two distinct populations of epithelial cells. Type II cells produce pulmonary surfactant lipids and.../profile/8773/arrayexpressuploader16cellgasinfluenzalineliquidproteinpulmonary surfactantsurfaceDec.12, 2014Falsegenome-profiling-of-mouse-pulmonary-epithelial-typE-GEOD-25778_A-AFFY-45Genome profiling of mouse pulmonary epithelial type II cellsNov.11, 2014Pulmonary alveoli contain two distinct populations of epithelial cells. Type II cells produce pulmonary surfactant lipids and surfactant-associated proteins (SP) required for maintaining alveolar surface tension at the air-liquid interface and host defense against respiratory pathogens. Type II cells are also progenitors for epithelial type I cells, a terminally differentiated elongated cell that covers microvascular endothelial cells and participates in gas exchange. Despite some indirect evidence, it is unknown whether subpopulations of type II cells exist. We created a line of transgenic mice expressing enhanced green fluorescent protein (EGFP) under control of the human SP-C promoter. Expression of EGFP may define a subpopulation of type II cells because it is 1) expressed in approximately 10% of type II cells, 2) appears much later in embryonic development than SP-C, and 3) selectively proliferates in mice infected with influenza A virus. To determine whether EGFP defines a unique subpopulation of type II cells, RNA was isolated from EGFP-positive and negative type II cells and hybridized to affymetrix arrays. Of the genes detected in EGFP-positive cells, most were equally detected in EGFP-negative cells. However, approximately 350 genes were selectively elevated ≥5-fold in EGFP-positive cells and 1500 genes selectively expressed by EGFP-negative cells. These findings suggest EGFP defines a subpopulation of type II epithelial cells in this line of transgenic mice. Type II cells were harvested from approximately 10 young adult (8-week) mice and sorted into EGFP-positive (sample EGFP-1) and EGFP-negative (sample nonEGFP-1) populations using a B-D FACSVantage SE cell sorter. RNA was prepared from approximately two million cells and hybridized to Affymetrix M430 2.0 array as a one by one comparison. The isolation and gene expression analysis of EGFP-positive and EGFP-negative type II cells was repeated a second (using EGFP-2 and nonEGFP-2 samples) and third (using EGFP-3 and nonEGFP-3 samples) time.E-GEOD-25778http://www.ebi.ac.uk/arrayexpress/experiments/E-GEOD-25778/samples/