Hepatocyte Transplantation for Acute Decompensated Liver Failure

Hepatocyte Transplantation for Acute Decompensated Liver Failure

The purpose of this research study is to determine whether liver cell transplantation can provide help for patients with liver failure who are unlikely to survive without some form of liver support. The goal of this research study is to determine if liver cell transplants can be effective until a liver transplant is received or until patients recover from their liver failure.

Orthotopic liver transplantation has become the treatment of choice for patients with acute liver failure with poor prognostic signs. Survival following hepatic transplantation has improved in the last decade for a number of reasons. These include improvement in immunosuppression, improved methods for preserving and transporting organs, use of donors which had been previously considered unacceptable, use of reduced-sized grafts , and the use of living-donor hepatic transplantation. Despite encouraging survival statistics, there continues to be significant morbidity and mortality associated with hepatic transplantation. In addition, the success of hepatic transplantation has broadened the indications for this form of therapy without a concomitant increase in the number of donors available for these patients.

Since the development of a method for isolating primary hepatocytes by collagenase perfusion, many investigators have demonstrated the efficacy of hepatocyte transplantation in the treatment of liver failure and inherited metabolic disorders in experimental animals. Treatment of liver diseases with transplantation of isolated hepatocytes rather than the whole liver has several theoretical advantages. Unlike the whole liver, isolated hepatocytes could be cryopreserved for instant availability and could be modified genetically or otherwise to enhance specific functions, stimulate proliferation or abrogate allograft rejection. Hepatocyte transplantation should be less stressful than whole liver transplantation because the host organ remains intact. Since the transplanted cells integrate into the host liver, they could provide restorative potential and the consequences of graft loss would be relatively minor. In addition, hepatocyte transplantation would not interfere with subsequent liver transplantation, should that become necessary.

Inclusion Criteria:

• Subjects will include those patients with ALF who are potential conventional liver transplant recipient candidates based on PELD criteria as well as those who would not be considered candidates for orthotopic liver transplantation (e.g. patients who appear to be too small or too ill for solid organ transplant or those who have a diagnosis that is a contradiction for whole organ transplantation, for example, systemic mitochondrial hepatopathy).
• If the patient is a candidate for orthotopic liver transplantation (per standard clinical criteria), they will be officially listed for liver transplantation as well as hepatocyte transplantation.
• If a subject is a potential conventional liver transplant recipient candidate and a donor liver is available; the patient will receive a solid organ transplant.
• Subjects ages 0-21 years old will be included in this study.

Exclusion Criteria:

The patient has:

1. Severe cardiovascular or respiratory disease at baseline and at the time of hepatocyte transplant as defined by

   1. Central venous pressure >25 mm Hg or if known, pulmonary capillary wedge pressure of >30 mg Hg or
   2. Oxygen saturation of <90% on > 60% oxygen OR a P/F ratio (Po2/FiO2) of <1.

2. Hemodynamically significant gastrointestinal bleeding causing a systolic blood pressure <70mmHg at the time of transplantation.

3. Uncorrectable coagulopathy despite use of plasmapheresis that would preclude any invasive procedures.

4. Leukopenia at the time of cell transplant, defined as an absolute neutrophil count of <500/µL.

5. Known allergy to immunosuppression medications that are required post transplant procedure for the prevention of rejection.

6. Active malignancy except those with acute liver failure during treatment with estimated life expectancies of >1 year if the malignancy is controlled.

7. Sepsis or other active infection except those without evidence of hemodynamically significant uncontrollable systemic sepsis with positive blood or tissue cultures.

8. Intrauterine pregnancy. All females of childbearing potential will receive a pregnancy test prior to enrollment.