Primary culture of microvascular endothelial cells from human benign prostatic hyperplasia

BACKGROUND. Prostate growth seems to be influenced by paracrine factors lik e IL-6 originating from the microvascular endothelium. Therefore, our effor ts were focused on the primary culture and behavior of microvascular endoth elial cells (HPEC) derived from tissue of human benign prostatic hyperplasi a (BPH). Until now, the isolation and culture of HPEC from BPH have not bee n reported. METHODS. BPH tissue was cut into small cubes and gently squeezed after incu bation with dispase. HPEC were cultured from the resulting cell suspension after a stepwise selection by use of sup erp ara magnetic beads coated with antibodies against endothelial specific antigens. HPEC were characterized by flow cytometry and immunohistochemistry. gamma -Glutamyl transpeptidase activity (specific for microvascular endothelium) was measured after dissol ution of the HPEC with Triton X-100. After the incubation of HPEC either wi th ATP, VEGF, or TNF-alpha, the release of IL-6 was measured by enzyme link ed immunosorbent assay (ELISA). RESULTS. HPEC showed a typical endothelial morphology. They were positive f or von Willebrand factor, CD31, CD62E (after stimulation with TNF-alpha), a lpha -actin and were negative for fibroblastic antigens and PSA. Proliferat ion was stimulated by vascular endothelial growth factor (VEGF). gamma -Glu tamyl transpeptidase activity in HPEC was 6.3 mu IU/mug protein, whereas in human umbilical vein endothelial cells (HUVEC) no gamma -glutamyl transpep tidase activity was detectable. The IL-6 secretion of HPEC was stimulated b y VEGF and TNF-alpha, but not by ATP and bradykinin. CONCLUSIONS. For the first time, the primary culture of microvascular endot helial cells from BPH tissue was successfully performed. Our results sugges t that HPEC may be actively involved in prostate growth, due to the secreti on of regulatory factors such ab IL-6.