While Lonza has never attempted to co-culture Prostate Epithelial Cells (PrEC) and Prostate Stromal Cells (PrSC) together in-house, the recommendation of Lonza Research & Development would be to plate and culture the PrEC and PrSC cells together in Lonza’s PrEGM™ Prostate Epithelial Growth Medium supplemented with 0.5% fetal bovine serum (FBS). Once established, altering the fetal bovine serum concentration may help to further optimize the culture. Lowering the fetal bovine serum concentration would aid in the proliferation of the epithelial cells, but may slow the proliferation or cause sloughing of the fibroblasts. Increasing the fetal bovine serum concentration would aid in the proliferation of the fibroblasts, but may slow the proliferation or cause sloughing of the epithelial cells.