Cloning of human thymic subcapsular cortex epithelial cells with T-lymphocyte binding sites and hemopoietic growth factor activity
Mizutani S., Watt SM., Robertson D., Hussein S., Healy LE., Furley AJ., Greaves MF.
The thymic microenvironment involves complex cell interactions among different types of epithelial cells, macrophages, tissue histiocytes, and immature and maturing T cells. We describe the isolation of a subset of thymic epithelial cells by selective primary culture followed by cotransfection with a simian virus 40 replication-origin-defective mutant and pSV2neo plasmid. The cloned cells have the composite immunophenotype that is unique to thymic subcapsular epithelial cells, suggesting that they may provide a model system in vitro for analyzing the earliest steps in T-cell differentiation. This possibility is supported by the finding that these epithelial cells express LFA-3-associated binding sites for T cells, secrete a macrophage hemopoietic growth factor, and synergize with macrophages in the production of interleukin 1.