ISOLATION OF VILLOUS MICROVESSELS FROM THE HUMAN PLACENTA

A method for isolating the microvessels of the human placental villi h as been developed in order to culture perivascular cells. It consists of an initial selection of the villi by serial sieving. The villi reta ined by the 75 mu m sieve were digested by collagenase-dispase. A Perc oll gradient permitted the isolation of microvessels still surrounded by stromal fibres and cells. Another digestion by collagenase-dispase eliminated the contaminant elements and allowed, after a new Percoll g radient, microvessels with endothelium, basement membrane and a few pe rivascular cells to be obtained. Each step of the isolation of microve ssels was monitored by light or electron microscopy. Our study confirm s the isolation of microvessels embedded in their basement membrane an d the preservation of endothelial and perivascular cells after digesti on. This method, which has permitted the culture of placental endothel ial cells and pericytes, appears of interest for studying microvascula r angiogenesis and permeability.