A perfused renal human organ culture model: Impact of monocyte attack

Background: Key processes of atherosclerosis and restenosis are triggered and/or modified by the contact of human monocytes (MCs) with the inner layers of the arterial vessel wall. This is the first report on monocyte attack in a perfused renal human organ culture model (perfused renal HOC-model). Material/Methods: Parts of the renal arteries were extracted during routine nephrectomies. A closed loop system was established by fixing the segments between two hard plastic tubes and connecting the distal endings of the hard plastic tubes with soft plastic tubes. 5x10 5 human MCs were added to the culture medium for a period of 24 h. Immunohistological staining was carried out before adding the MCs and after 2, 24, 48, and 72 hours. Results: Perfusion of the model with culture medium was performed with a steady flow of 1.6 ml/min. One, two, and three days after adding the intravascular MCs, almost no extravascular MCs were detected. Although the number of MCs was merely slightly increased on the endothelium, in the plaque-intima, and in the media, a large number of MCs was detected in the adventitia. During the three-day period of steady flow perfusion, no stimulation of smooth muscle cell proliferation in the artery wall was detected. Conclusions: Steady perfusion of the renal HOC-model is an important step in the attempt to adapt human ex vivo models to the various roles of inflammation in the pathophysiology of atherosclerosis and restenosis.