Comparison of marker protein expression in benign prostatic hyperplasia invivo and in vitro

Objective To use multiple immunofluorescence to compare the in vivo and in vitro expression of tissue-specific proteins in BPH, Materials and methods Pure populations of prostate epithelial and stromal c ells were produced using standard methods. Serum-free media for epithelial cells were compared. Go-localization of proteins was compared in frozen-tis sue sections and cultured cells by simultaneous multiple immunofluorescence , and recorded using a high-resolution charge-coupled device camera. Results In contrast to the other serum-free media tested, epithelial cells grew without squamous differentiation or vacuolation in prostate epithelial growth medium (PrEGM, Clonetics, BioWhittaker UK Ltd., Berks, UK), These c ells were predominantly of a basal phenotype, with some cells showing a lum inal phenotype. Most of the stromal cells had features of myofibroblasts, b ut smooth muscle cells and fibroblasts also were present. Conclusion PrEGM is a commercially available serum-free medium in which pri mary cultures of prostate epithelial cells can be propagated reproducibly. This study provides a comprehensive description of tissue-specific protein expression in BPH in vivo and in vitro. The use of simultaneous multiple im munofluorescence to study co-localization has resulted in a more precise de finition of phenotype than has previously been possible, thereby establishi ng the relevance of the in vitro model system BPH.