Mouse mammary epithelial cell subpopulations from pregnant and virgin mice. Mus musculus

To study the effect of pregnancy on mouse mammary epithelial subpopulations, epthelial cells derived from virgin or pregnant (12.5 day pregnant) mice were isolated using fluorescence-activated cell sorting. After elimination of haematopoietic and endothelial cells, two distinct epithelial subpopulations were sorted using antibodies against CD29 and CD24. Based on the immunohistochemical phenotype, and in vivo and in vitro functional assays, these subpopulations were identified as mammary stem cell enriched (CD29hiCD24+) and luminal (CD29loCD24+) respectively (ref: Shackleton et al, Nature 2006). Microarray profiling was used to compare gene expression profiles of the two subpopulations in 12.5 day pregnant and virgin mice. Overall design: For each biological replicate, mammary gland from virgin or 12.5 day pregnant FVB/NJ mice were collected and digested to obtain a single cell suspension. CD45-CD31-TER119- cells were then sorted based on the expression of cell surface markers CD24 and CD29. There were 4 pools of pregant mice and 3 pools of virgin mice.