Bioartificial Liver System as Bridge to Liver Transplantation
September 30, 2013 | Technology Forecasts
Liver failure results from the loss of liver function and is associated with a high risk of mortality.1 Liver transplantation is considered the only effective long-term therapeutic option for patients with liver failure; however, the number of patients who need liver transplants exceeds the number of donor organs available.1 To temporarily support a failing liver, two types of liver support devices have been developed: artificial livers and BALs. Artificial livers are designed to filter toxins from the blood and function similarly to kidney dialysis; they often use the same dialysis platform with additional modular components and filters.2 The most advanced artificial liver systems use albumin-based filtration that can remove both protein-bound and water-soluble toxins from the blood.2 However, because the liver also provides functions beyond detoxification (e.g., synthesis, regulation), these systems are often inadequate for extended use.
BALs are cell-based, extracorporeal (external to the body) devices designed to detoxify and synthesize proteins and metabolites in the blood.1 BALs comprise bioreactors of hepatocytes (liver cell), typically derived from either hepatoblastoma cell lines or porcine livers, and a combination of physical and chemical procedures.1 Depending on the design, the hepatocytes may or may not have direct contact with the patient's blood.1 During BAL treatment, the patient is connected to the device through a double-lumen catheter, usually inserted into the superficial femoral vein.1,2 The patient's blood is shunted to the device and continuously separated into plasma and cellular components.1 The hepatocytes are purported to further detoxify the plasma and replace missing essential proteins and nutrients in the plasma.1 The treated plasma is then remixed with the blood cells and returned to the patient.1 BAL treatment is intended to temporarily support the liver functions while a patient is awaiting a compatible donor or ideally to help the liver regenerate spontaneously.
The ELAD comprises four bioreactors of cultured proprietary C3A human hepatocytes that can grow in unlimited quantities and hollow fibers.3 ELAD treatment is intended for use 24 hours per day for at least 3 days, providing up to 30 days of continuous support to patients with compromised liver function.4
The Bioartificial Liver Support System® (BLSS®; Excorp Medical, Inc., Hong Kong, China) uses a hollow fiber cartridge of cryopreserved porcine hepatocytes that are freshly isolated from controlled animals in a high health status herd.5 BLSS treatment is designed to...