Microcarrier cultures in vascular endothelial research

Endothelial cells isolated from bovine aorta and human umbilical vein were cultured on solid plastic microspheres. The cells were characterised with respect to morphology, growth rates, density-dependent inhibition of growth and synthesis of prostaglandin I2 and were found to behave in all respects as their counterparts cultured in plastic dishes. A cell:bead ratio of 5 at inoculation resulted in confluent monolayer cultures (= 150 cells per bead) within 12 days in stationary culture. Fibroblast growth factor (FGF) slightly improved bovine endothelial growth from low inoculation densities. Neither FGF nor fibronectin improved human endothelial growth. Continuous culture of endothelium and sub-culture without the use of proteolytic enzymes were demonstrated. The microcarrier system was used for the precise co-cultivation of endothelial cells with arterial smooth muscle cells in order to study cell-cell interactions without cell-cell contact. Cells on microcarriers were maintained in a shallow column perfused by culture medium. Under such conditions, with appropriate stimuli, concentrated products synthetised by endothelium were collected. The microcarrier system allows several important questions in vascular cell biology and pathology to be addressed more readily than is possible with conventional culture techniques.