Background. Modifications in vitro have been used to direct embryonic stem (ES) cells toward endodermal phenotypes including hepatocytes; however, developmental correlates and evidence of biologic ...activity is lacking, and critical cell-cell interactions have not been investigated. In this study, we hypothesized that cardiac mesoderm (CM) signals ES cells in co-culture to undergo differentiation toward early hepatocyte lineage as determined by morphology and induction of genes essential for endodermal competence and hepatocyte development. Methods. Green fluorescent protein ES derived from A129 mice were cultured with or without embryonic chick cardiac mesoderm. Cultures from day 1, 2, and 4 were analyzed for colony formation and ES morphology and 106 ES-derived cells were isolated for mRNA analysis. Results. ES in co-culture with CM displayed colony formation, polymorphic appearance, and definitive interface with CM. In addition, ES + CM co-culture activated crucial transcription factors (sox 17α, HNF3β, and GATA 4) required for hepatocyte development by day 1. mRNA for albumin and especially a-fetoprotein were also increased by culture days 2 and 4. Conclusions. ES cells co-cultured with CM display morphology and gene expression pattern required for hepatocyte differentiation and appear to recapitulate the molecular events of hepatogenesis. (Surgery 2003;134:189-96.)
Background Embryonic stem (ES) cells have been investigated as a potential replacement therapy for failed organs, such as the liver. However, detection of hepatic engraftment from candidate stem ...cells has been difficult due to low engraftment efficiency. Previous detection methods required that the graft be processed by molecular and/or immunohistochemical techniques, limiting further functional studies. This study evaluated the use of three-dimensional fluorescent stereomicroscopy for gross detection of ES cell derived hepatic engraftment. Material and Methods Murine ES cells expressing the enhanced green fluorescence protein (EGFP) underwent directed endodermal lineage differentiation. Three days after two thirds partial hepatectomy, cells were injected into the liver parenchyma, and livers were harvested at 10 to 20 d and examined by fluorescence stereomicroscopy with a GFP2 long pass filter (100447084; Leica Microsystems AG, Wetzlar, Germany). The sensitivity and reliability of the test was evaluated using quantitative polymerase chain reaction (q-PCR) to assay for the presence of EGFP mRNA in the tissue. Results Fluorescent microscopy detected EGFP-positive cells engrafted with normal histology in 5 of 11 specimens. EGFP mRNA was confirmed in all five specimens by q-PCR. Only one of the 11 specimens was negative by fluorescence stereomicroscopy and positive by q-PCR, P < 0.02, Fisher’s exact test. Conclusion Utilization of three-dimensional stereomicroscopy with a GFP2 long pass filter is a powerful and fast screening tool for GFP-ES derived hepatic engraftment.
Hepatopulmonary syndrome (HPS) is defined by the presence of the triad of liver disease, arterial hypoxemia, and intrapulmonary vascular dilatation. The clinical implication of this disorder is ...impairment of gas exchange. Numerous reports in the literature show that this condition is reversible with orthotopic liver transplantation (OLT). However, patients with HPS often present with Pa
O
2 levels that are quite low. OLT with a preoperative Pa
O
2 less than 50 mm Hg is associated with unacceptably high mortality and morbidity. We report a case of severe HPS in which a transjugular intrahepatic portosystemic shunt was successfully used to improve oxygenation, thus allowing a successful elective OLT. (
Liver Transpl 2001;7:147-149.)
To determine the efficacy of primary Gianturco stent placement for patients with inferior vena caval (IVC) abnormalities following liver transplantation.
From August 1996 through March 1999, nine ...adult patients developed significant IVC abnormalities following liver transplantation. Patients were referred for vena cavography on the basis of abnormal clinical findings, laboratory values, liver biopsy results, Doppler findings, or a combination. Those patients demonstrating a significant caval or hepatic venous gradient were treated with primary Gianturco stent placement. Patients were followed clinically (nine patients), with duplex ultrasound (nine patients), vena cavography (four patients), and biopsy (seven patients).
Original pressure gradients ranged from 3 to 14 mm Hg, with a mean of 9 mm Hg. Gradients were reduced to 3 mm Hg or less in all nine patients; presenting signs and symptoms either resolved or improved in eight of nine patients. The ninth patient required repeated transplantation 2 days later. A second patient died 433 days after stent placement of recurrent hepatitis C. Another initially improved following caval stent placement, but underwent repeated transplantation 7 days later due to hepatic necrosis from hepatic arterial thrombosis. Follow-up for the remaining six patients has averaged 491 days, with no clinical, venographic, or ultrasound evidence for recurrent caval stenosis.
Intermediate term results suggest that primary Gianturco stent placement for IVC stenosis, compression, or torsion resulting after liver transplantation is safe and effective.
Living donor liver transplantation in adult recipients is becoming increasingly common. The liver metabolizes most drugs, including immunosuppressive agents. Right-lobe grafts used in adult living ...donor liver transplantation consist of only 50% to 60% of the total liver. The purpose of this study is to determine whether there is a difference between tacrolimus doses and concentrations in patients who received a partial liver transplant from a living donor (LRD) versus those who received a whole-liver transplant from a cadaveric donor (CAD). Thirteen LRD recipients and 13 CAD recipients who underwent transplantation between April 1998 and July 2000 were included in this analysis. A CAD control group matched for age, sex, and race was used for comparison. Tacrolimus doses and concentrations were analyzed weekly for the first 4 weeks, then monthly for 6 months posttransplantation. There was no difference in acute rejection rates, renal and liver function test results, or number of potentially interacting medications administered between groups. LRD recipients required significantly lower doses of tacrolimus compared with CAD recipients at 2 weeks (0.058 v 0.110 mg/kg/d; P lt .01), 3 weeks (0.068 v 0.123 mg/kg/d; P lt .02), 4 weeks (0.086 v 0.141 mg/kg/d; P lt .02), 2 months (0.097 v 0.141 mg/kg/d; P lt .03), and 3 months (0.099 v 0.138 mg/kg/d; P lt .03). Tacrolimus 12-hour trough concentrations were similar between groups at all times except for 2 weeks posttransplantation, when LRD recipients' concentrations were significantly greater than those of CAD recipients (12.4 v 9.5 ng/mL; P lt .03). In addition, in the first month posttransplantation, LRD recipients were more likely to have greater concentrations of tacrolimus (gt 15 ng/mL; 22.1% v 9.2%; P lt .01). In conclusion, LRD recipients have significantly decreased tacrolimus dosing requirements compared with CAD recipients during the first 3 months posttransplantation despite having similar tacrolimus concentrations. (Liver Transpl 2002;8:219-223.)
Although several studies have identified posttransplant neurologic sequelae in patients with acute liver failure (ALF), the effects of these sequelae on neuropsychologic functioning after transplant ...is unknown. This study compared neuropsychologic functioning of ALF patients with chronic liver disease patients after liver transplantation. After liver transplantation, seven ALF patients were compared with a matched control group of patients who had been transplanted for chronic liver disease. The patients were matched by gender, age (within 5 years), and time since transplantation (within 2 years). Patients completed a 2-hour battery of tests, which included measures of attention, memory, motor performance, abstract conceptualization, and visuospatial perception. There were no significant differences between the groups on measures of socioeconomic status or education. Significant differences were found on three separate tests: WAIS-III Vocabulary, WAIS-III Similarities, and WMS-III Paired Associate Learning II. Although these tests measure distinct functions (vocabulary knowledge, abstract conceptualization, and delayed verbal recall), they may be influenced by broader verbal functions, such as verbal fluency, conceptualization, and the ability to articulate ideas. When patients were asked what functions had noticeably deteriorated since transplantation, nearly all complained of memory difficulties, and there was no difference between groups. However, more ALF than chronic liver disease (CLD) patients complained of concentration difficulties. The results of this study suggest that ALF patients may experience more neuropsychologic dysfunction after transplant. Further studies are required to expand on these initial observations with the potential to improve patient care and referral to appropriate rehabilitative services. (Liver Transpl 2002;8:932-936.)
Despite the increasing use of living donor liver transplantation, little is known about donor needs, concerns, and experiences. The goal of this study is to assess morbidity associated with living ...donation from a donor perspective, functional status after donation, and overall satisfaction with the donation process. We surveyed all living donors (LDs) from our center. Demographics, perioperative experience, and satisfaction with donation were assessed. The Medical Outcomes Study 12-Item Short-Form Survey (SF-12), a well-validated tool, measured overall health-related quality of life. Of 27 subjects eligible for the study, 27 subjects (100%) participated. Forty percent reported an event they deemed an immediate complication, of which 60% were recorded in the medical record. Complications requiring readmission were reported by 22%. Mean recovery time was 12 weeks (range, 1 to 52 weeks). No significant change was reported in physical activity, social activity, or emotional stability, and 92% of donors resumed their predonation occupation. Regardless of recipient outcome, 100% of donors would donate again and recommend donation to someone in contemplation. All surveyed LDs at our institution are satisfied with their donation decision. Morbidity in the first year after donation may be greater than previously appreciated. Despite complications, postoperative functional status of donors is equal to or better than population norms. (Liver Transpl 2001;7:943-947.)
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