[Artificial and bioartificial liver support systems for acute and acute-on-chronic liver failure: a meta-analysis].

OBJECTIVE: To evaluate the effect of artificial and bioartificial liver support systems for management of acute and acute-on-chronic liver failure. METHODS: Articles documenting randomized clinical trials concerning any liver support systems vs standard conservative therapy, published between January, 1970 and June, 2008, were retrieved by database searching. Of the 1134 articles retrieved, 12 randomized trials involving 479 patients were included. The data were extracted and the trial quality was assessed by 2 independent reviewers. The primary outcome measure was all-cause mortality, and the results were combined on the risk ratio (RR) scale. RESULTS: Of the 12 trials included, 10 assessed artificial liver support systems for acute or acute-on-chronic liver failure, and 2 assessed bioartificial systems for acute liver failure. Overall, the liver support systems had moderate effect on mortality compared with standard conservative therapy (RR=0.80; 95% CI 0.664-0.969, P=0.022). Meta-regression indicated that the effect of the support systems depended on the type of liver failure (P=0.00). In stratified meta-analyses, the support systems appeared to reduce the mortality by 43% in acute-on-chronic liver failure (RR=0.57; 95% CI 0.39-0.84, P=0.004), but not in acute liver failure (RR=0.899; 95% CI 0.72-1.12, P=0.361). CONCLUSION: Artificial liver support systems reduce the mortality of acute-on-chronic liver failure as compared with standard conservative therapy, but have no significant effect on the mortality of acute liver failure. Bioartificial liver support systems lower the mortality rates in both acute and acute-on-chronic liver failure, and should be the future focus of development.

[Decellularization technology application in whole liver reconstruct biological scaffold].

OBJECTIVE: To explore an innovative method for preparation of a whole-liver reconstruct scaffold with intact three-dimensional geometry, vasculature and bile duct by decellularization technology. METHODS: The portal vein was annulated and perfused sequentially with 1%Triton X-100 and 1%SDS for about 4 h, and then was perfused with phosphate buffered saline to dilute SDS residue. The retained structure was evaluated by histological analyses, including macroscopic, Hematoxylin-Eosin staining, Masson's trichrome staining, orcein staining and SEM. The liquid polymer preparation 8% - 10%, which was made of chlorinated poly vinyl chloride (CPVC as solute), acetone (as solvent) and pigment, was injected into portal vein and bile duct to demonstrate the integrity of the portal vein and bile duct. The scaffold was cut into slices with the thickness of about 50 microm and cocultured with C3A cell line. RESULTS: Macroscopic examination showed that the decellularized liver was transparent and intrahepatic Glisson's system could be observed. H&E staining of slices of decellularized liver demonstrated no intact cells or nuclei existed. Masson trichrome staining revealed collagen retained. Orcein staining showed that there were elastic fibers. SEM showed the network of ECM was intact. C3A-to-scaffold co-culture revealed the scaffold of good biocompatibility. CONCLUSION: Perfusion with detergents through portal vein for liver decellularization was an efficient method to obtain a completely whole-liver scaffold which can be used for hepatic organ reconstruction.

[Preparation of whole-kidney acellular matrix in rats by perfusion].

OBJECTIVE: To prepare rat whole-kidney acellular matrix (ACM) scaffolds using fluid perfusion method. METHODS: The kidneys with ureters and renal vessels were harvested from 12-week-old Wistar rats. Intravenous catheters were inserted through the renal arteries to establish channels for whole-kidney retrograde perfusion successively with heparinized PBS, 1% SDS, deionized water, 1% TritonX-100 and antibiotic-containing PBS under a pressure of 100 cmH2O. After decellularization, the scaffolds were observed under microscope with HE staining, scanning electron microscope, and fluorescence microscope with DAPI fluorescence staining. RESULTS: No cell residue was found in the scaffolds under microscope. Scanning electron microscope identified reticular structures consisting of basilar membrane and collagen without normal cellular structures in the scaffolds, and no strong fluorescence due to the binding of DAPI to the cell nuclei was observed under fluorescence microscope. CONCLUSION: Fluid perfusion is simple and reliable to prepare rat whole-kidney acellular matrix, which may serve as an ideal cell-free scaffold.