Changes in Cell Surface Molecules Associated with in Vitro Culture of Prostatic Stromal Cells

Background: Prostate stromal cells can be readily cultured in vitro. Are these proliferating cells representative of stromal cells in situ? Since the expression of cell surface molecules, like the cluster of differentiation (CD) antigens, can be affected by changes in physiological conditions cultured stromal cells may differ from uncultured stromal cells in their complement of CD molecules.

Methods: Prostate stromal cells were prepared from tissue specimens and cultured. Flow cytometry was used to analyze the expression of 107 CD molecules in the resultant cells. Expression of the CD molecules by prostate cells in situ was done by immunohistochemistry.

Results: The expression of a number of cell surface molecules such as CD10, CD13, CD26, and CD44 is elevated in prostatic stromal cells cultured in vitro. These are markers of epithelial cells in tissue. Other molecules expressed by the cultured stromal cells include CD29, CD49a, CD49b, CD49d, CD49f, CD51/61, CD54, CD55, CD56, CD58, CD59, CD61, CD71, CD79b, CD81, CD82, CD90, CD95, CD107a, CD130, and CD147. Among these are stromal, epithelial, and nonstromal/nonepithelial markers as defined by tissue immunohistochemistry.

Conclusion: Cultured stromal cells express a number of CD molecules normally found in other cell types of the prostate. Cells can express different CD molecules under different conditions.