Cellular Localization of Lipoprotein Receptors in Liver

Abstract

Investigations on the quantitative role of the various cell types (parenchymal, Kupffer and endothelial cells) to the receptor-mediated uptake by the liver in vivo, were until recently hampered by the applied cell isolation procedures during which bound and/or internalized substances were processed and lost from the cells. The procedure as outlined in scheme 1 prevents such a processing because both liver perfusion, cell separation and cell purification are performed at a low temperature (at 8° C). In addition one is able to assess the recovery by comparing the radioactivity in the purified parenchymal, endothelial and Kupffer cells (all obtained from one liver) to the radioactivity originally present in the whole rat liver. The method was evaluated using¹²⁵ I-asialofetuin as the substrate (Fig. 1) and compared to quantitative autoradiographic data [1].