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The adenosine triphosphate (ATP)-binding cassette (ABC)-transporters ABCG5 and ABCG8 have been shown to mediate hepatic and intestinal excretion of cholesterol. In various (genetically modified) marine models, a strong relationship was found between hepatic expression of ABCG5/ABCG8 and biliary cholesterol content. Our study aimed to relate levels of hepatic expression of ABCG5 and ABCG8 to biliary excretion of cholesterol in man. From 24 patients who had received a liver transplant, bile samples were collected daily after transplantation over a 2-week period to determine biliary composition. Expression of ABCG5, ABCG8, MDR3, and BSEP was assessed by real-time polymerase chain reaction (PCR) in liver biopsy specimens collected before and after transplantation. Levels of hepatic ABCG5, ABCG8, and MDR3 messenger RNA (mRNA) were strongly correlated. After transplantation, the biliary secretion rate of cholesterol continuously increased, coinciding with gradual increases in bile salt and phospholipid secretion. In contrast, hepatic levels of ABCG5 and ABCG8 mRNA remained unchanged. Surprisingly, no correlation was found between the hepatic expression of ABCG5 and ABCG8 and rates of biliary cholesterol secretion, normalized for biliary phospholipid. secretion. As expected, the concentration of biliary phospholipids correlated well with MDR3 expression. In conclusion the strong relationship between ABCG5 and ABCG8 gene expression is consistent with the coordinate regulation of both genes, and in line with heterodimerization of both proteins into a functional transporter. Hepatic ABCG5/ABCG8 expression, at least during the early phase after transplantation, is not directly related to biliary cholesterol secretion in humans. This finding suggests the existence of alternative pathways for the hepatobiliary transport of cholesterol that are not controlled by ABCG5/ABCG8.

Besides the conventional laboratory tests, thromboelastography (TEG) is used to monitor hemostasis during liver transplantation. A previous pilot study suggested a beneficial effect of recombinant activated factor VII (rFVIIa) on transfusion requirements in liver transplantation. In the present study, we assess the effects of rFVIIa on coagulation variables and TEG. In six study patients, the prothrombin time (PT), the activated partial thromboplastin time (aPTT) and TEG variables [reaction time (r), kinetic time (k), or clot formation time, alpha angle (alpha), and maximal amplitude (MA)] were recorded before and after the administration of a bolus of 80 microg/kg rFVIIa. These patients were compared with six controls who did not receive rFVIIa. In contrast with the control group, a significant shortening of PT (P = 0.028) and aPTT (P = 0.028), r (P = 0.046) and k (P = 0.043) values, and a significant incline of the alpha angle (P = 0.028) were noticed after injection of rFVIIa, whereas MA increased not significantly (P = 0.075). rFVIIa rapidly improved coagulation variables in liver transplant patients including PT and aPTT. Of the TEG variables, r, k and alpha angle significantly improved, and MA showed a trend to increase. These data suggest that rFVIIa not only influences the speed of clot formation, but also the physical properties of the clot, which cannot be detected by routine coagulation tests.

Background. Large transfusion requirements, i.e., excessive blood loss, during orthotopic liver transplantation (OLT) are correlated with increased morbidity and mortality, Recombinant factor VIIa (rFVIIa) has been shown to improve hemostasis in a variety of conditions, but has never been studied in liver transplantation. Methods. We performed a single-center, open-label, pilot study in adult patients undergoing OLT for cirrhosis Child-Pugh B or C, to assess efficacy and safety of rFVIIa. rFVIIa (80 mug/kg) was administered at the start of the operation, to be repeated according to predefined criteria, Packed red blood cells (RBC), fresh-frozen plasma, and platelet concentrates were administered according to predefined criteria, Perioperative transfusion requirements in study patients were compared with matched controls, Results. Six patients were enrolled in the study, All received a single dose of rFVIIa, Transfusion requirements (given as median, with range in parentheses) were lower in the study group than in matched controls: 1.5 (0-5) vs. 7 (2-18) units of allogeneic RBC (P=0.006), 0 (0-2) vs. 3.5 (0-23) units of autologous RBC (P=0.043), total amount of RBC 3 (0-5) vs. 9 (4-40) units (P=0.002). Transfused fresh-frozen plasma was 1 (0-7) vs, 8 (2-35) units P=0.011). flood loss was 3.5 L; (1.4-5.3) vs, 9.8 L (3.7-35.0) (P=0.004), One study patient developed a hepatic artery thrombosis at day 1 postoperatively. Conclusions. A single dose of 80 mug/kg rFVIIa significantly reduced transfusion requirements during OLT, Further study is needed to establish the optimally effective and safe dose of rFVIIa in orthotopic liver transplantation.

Background. The development of immunological donor-specific hyporeactivity may account for the low incidence of chronic rejection after clinical liver transplantation. We investigated whether hyporeactivity commonly develops after liver transplantation by analyzing precursor frequencies of donor-reactive cytotoxic (CTLp) and helper (HTLp) T lymphocytes and mixed lymphocyte culture (MLC) reactivity in liver allograft recipients. We further studied whether CTLp hyporeactivity correlated with changes in donor-specific HTLp frequencies or suppressor cell activity. Methods. CTLp and HTLp frequencies and MLC reactivity against donor and third-party spleen cells were determined in pre- and posttransplantation peripheral blood samples from 18 recipients with good graft function 2 years after transplantation. By mixing posttransplantation samples (with "putative" suppressor cell activity) with pretransplantation samples tin which normal CTL activity with no suppressor cell activity is expected), the presence of suppressor cell activity in peripheral blood was analyzed. Results. Two years after transplantation, all but one (94%) of the recipients had developed CTLp hyporeactivity as evidenced by reduced donor-specific CTLp frequencies. The development of hyporeactivity was not specific for any particular underlying disease. The occurrence of HTL hyporeactivity, however, was less frequent: 38% and 20% of recipients were HTLp and MLC hyporeactive, respectively. Decreases in CTLp frequencies did not correlate with decreased donor-specific HTL function or suppressor cell activity in peripheral blood samples. Conclusions. Donor-specific CTLp hyporeactivity can develop in the majority of liver allograft recipients, irrespective of underlying disease. Donor-specific HTL hyporeactivity, however, occurs infrequently. A reduction in donor-specific CTLp frequencies was found to be independent of changes in donor-specific HTLp or suppressor cell activity, suggesting that other mechanisms (e.g., clonal deletion) are operative in the reduction of donor-specific CTLp after liver transplantation.

Background. Methods to quantitate the effects of immunosuppressive drugs on immune reactivity might be helpful for monitoring immunosuppressive treatment. Cyclosporine (CsA) inhibits the induction of cytokine synthesis in T cells, and measurement of interleukin (IL)-2 production might constitute a parameter of this drug's effect. Methods. We determined the percentages of CD4(+) and CD8(+) lymphocytes producing IL-2 upon stimulation by phorbol myristate acetate and calcium ionophore in whole blood culture, using immunostaining of intracytoplasmatic and membrane markers, followed by multiparameter flow cytometry. A total of 38 clinically stable transplant patients on various immunosuppressive protocols were studied. Results. The percentage of CD4(+) T cells producing IL-2 was strongly reduced in patients compared with healthy controls (23% [range, 3-68%] vs. 59.0% [range, 41-70%]; P=0.000035). The percentage of CD4(+) T cells producing IL-2 was negatively correlated with the CSA level (R-c=-0.0821, P=0.00002297) but not with prednisolone or azathioprine doses. Fewer CD8(+) T cells produced IL-2 in transplant patients compared with controls, but the difference failed to reach statistical significance. The percentage of CD8(+) T cells capable of producing IL-2 was inversely correlated to CsA levels (R-c= -0.0375, P=0.0011). Conclusions. These data suggest that the functional effects of CsA in transplant recipients can be quantitatively determined and that the capacity of CD4(+) T cells to produce IL-2 upon stimulation constitutes a functional parameter of CsA effects on the immune system. Prospective studies are required to determine whether this method is useful for clinical monitoring.

To determine the relation between tissue hydration state-as indicated by tissue proton magnetic resonance relaxation times-in UW-preserved human donor livers and viability parameters of the donor and early graft function, ''ex vivo'' magnetic resonance relaxometry was performed with a clinical MR imaging system. Relaxometric data were obtained from MR images in which signal intensities were directly proportional to T-1 and T-2. Forty three subsequently transplanted livers and five discarded livers were studied. The donor serum concentrations of direct and total bilirubin had a positive correlation with T-1 (P

Analysis of quality-of-life effects is part of the current technology assessment of the Dutch orthotopic liver transplant-program. Data are collected by means of computer-assisted interviewing, including one interview before transplantation and annual follow-up interviews. Data on psychiatric morbidity are obtained from medical records. This article shows preliminary results of a cross-sectional analysis of data collected from 1987 to 1989. Eighty-eight measurements were obtained from 46 adult patients (response rate 82%). Pretransplant scores suggest major restrictions on all domains of life, especially a low amount of energy. After transplantation all indicators show improvement, although the level of the general population is not always attained. Improvement of subjective quality of life is more marked, possibly due to euphoria at surviving the hazardous procedure. Psychiatric events occurred only infrequently. We conclude that orthotopic liver transplantation contributes positively to the quality of life of surviving patients. In addition, computer-assisted interviewing proved to be a feasible survey technique, even when very ill patients were involved.