Isolation Of Parenchymal Cells Research Articles

Comparison between a Multifunctional Envelope-Type Nano Device and Lipoplex for Delivery to the Liver

The utility of using a multifunctional envelope-type nano device (MEND) for delivering a gene to the liver was examined. Lipotrust, a commercially available transfection reagent whose lipid composition is DC6- 14 :DOPE: cholesterol=4 : 3 : 3, was used as a reference. When Lipotrust was administrated intravenously, luciferase activity of the lung was 25 times higher than that of the liver. The luciferase activity of the lung was greatly reduced when a MEND was administered, even though the lipid composition of the lipid envelope was the same in both devices. Furthermore, the luciferase activity of the liver was 5 times higher than that for lipotrust, suggesting that the encapsulation of plasmid DNA (pDNA) in liposomes is more advantageous for delivering pDNA to the liver than complex formation. The isolation of parenchymal cells (PCs) and non-parenchymal cells (NPCs) showed that the MEND system is capable of expressing the luciferase protein more preferentially in NPCs than the lipoplex system. In addition, when the surface was modified with a pH-sensitive fusogenic peptide (GALA) used as a device for endosomal escape, overall liver luciferase activity was greatly enhanced. This suggests that endosomal escape is a limiting step for the MEND system. In the case of the GALA-modified MEND, the luciferase activity of PCs and NPCs was 18 times and 11 times higher than MEND system, while the transfection efficiency of NPCs was significantly higher compared to that of PCs. Collectively, these data show that a GALA-modified MEND prepared with DC6-14 :DOPE: cholesterol represents a promising device for NPCtargeting gene delivery in vivo.

Isolation and characterization of parenchymal cells from experimentally induced macronodular rat liver cirrhosis

Hepatocytes were isolated from thioacetamide (TAA)-induced macronodular cirrhotic rat livers by a collagenase perfusion method. In the content of cellular metabolites, fatty acid uptake and lipid secretion there were no substantial differences compared with cells isolated from micronodular cirrhosis described previously. In contrast to isolated hepatocytes from normal livers those from macronodular cirrhosis had a lowered cellular content of triglycerides, phospholipids and cholesterol but not of cholesterol esters and free fatty acids. In macronodular cirrhosis hepatocytes of hypertrophic type, rich in cell organelles, can be distinguished ultrastructurally from those with signs of atrophy and degeneration. Immediately after isolation many hepatocytes isolated from macronodular cirrhosis showed plasma membrane blebbing. Whereas the blebbing was without recognizable effects on the fine structure of the isolated hepatocytes of the hypertrophic type, in the more atrophic ones some mitochondria were swollen. In addition, morphological analysis of the crude and purified suspensions revealed a partial selection of the hypertrophic cells during the isolation procedure, presumably due to a more labile state of those cells which showed signs of atrophy and degeneration. When stabilized in the suspension medium, however, the hepatocytes maintained complex metabolic functions for at least 2 h. Thus, the method described allows the isolation of parenchymal cells from TAA-induced macronodular cirrhotic livers for studying ultrastructural and biochemical alterations in hyperregenerative experimental liver cirrhosis.