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R A Chamuleau

Publications and source records attributed to R A Chamuleau.

At least 19 recordsLinked to original sources
PubMed2001

Apolipoprotein A-V: a novel apolipoprotein associated with an early phase of liver regeneration.

Liver regeneration in response to various forms of liver injury is a complex process, which ultimately results in restoration of the original liver mass and function. Because the underlying mechanisms that initiate this response are still incompletely defined, this study was aimed to identify novel factors. Liver genes that were up-regulated 6 h after 70% hepatectomy (PHx) in the rat were selected by cDNA subtractive hybridization. Besides known genes associated with cell proliferation, several novel genes were isolated. The novel gene that was most up-regulated was further studied. Its mRNA showed a liver-specific expression and encoded a protein comprising 367 amino acids. The mouse and human cDNA analogues were also isolated and appeared to be highly homologous. The human gene analogue was located at an apolipoprotein gene cluster on chromosome 11q23. The protein encoded by this gene had appreciable homology with apolipoproteins A-I and A-IV. Maximal expression of the gene in the rat liver and its gene product in rat plasma was observed 6 h after PHx. The protein was present in plasma fractions containing high density lipoprotein particles. Therefore, we have identified a novel apolipoprotein, designated apolipoprotein A-V, that is associated with an early phase of liver regeneration.

Amino Acid Sequence↗
PubMed2001

Sustained virological response in chronic hepatitis C patients after a 6- and a 36-month interferon-alpha2b treatment schedule: a multicenter, randomized, controlled study.

BACKGROUND: In patients with chronic hepatitis C (HCV) Interferon-alpha (IFN) treatment for 12-18 months is more effective than 6 months in inducing a sustained virological response. METHODS: In a multicenter, randomized, controlled trial, 88 patients with chronic HCV were enrolled (47 treated with IFN-alpha2b and 41 constituted an untreated control group). Treatment consisted of 5 million units (MU) IFN thrice a week (tiw) for 8 weeks and subsequently 2.5 MU IFN tiw for 16 weeks ('standard treatment'). After week 24 ('long-term treatment'), in virological non-responders treatment was continued using 5 MU IFN tiw for up to week 156, whereas in virological responders IFN was discontinued. In case of a virological relapse, treatment with 5 MU IFN tiw was restarted and continued up to week 156. RESULTS: Sustained virological response rate was 6/47 (13%) after standard treatment and increased to 19/47 (40%) after long-term treatment (McNemar paired test; P = 0.002). Of the 18 patients with a breakthrough or relapse during or after standard treatment, 14 (78%) became sustained virological responders upon long-term treatment. Of the 4 patients who did not have a sustained virological response after long-term treatment, 3 did not receive complete treatment due to side effects and/or non-compliance. In patients who failed to respond to standard treatment, no virological response was observed during long-term treatment. In the control group, no spontaneous clearance of HCV was observed. CONCLUSIONS: Long-term IFN (re)treatment enhanced the virological sustained response rate significantly and was particularly effective in patients with a breakthrough or relapse following standard treatment.

Adult↗
PubMed2001

Extrahepatic portal vein thrombosis: aetiology and determinants of survival.

BACKGROUND: Malignancy, hypercoagulability, and conditions leading to decreased portal flow have been reported to contribute to the aetiology of extrahepatic portal vein thrombosis (EPVT). Mortality of patients with EPVT may be associated with these concurrent medical conditions or with manifestations of portal hypertension, such as variceal haemorrhage. PATIENTS AND METHODS: To determine which variables have prognostic significance with respect to survival, we performed a retrospective study of 172 adult EPVT patients who were followed over the period 1984-1997 in eight university hospitals. RESULTS: Mean follow up was 3.9 years (range 0.1-13.1). Overall survival was 70% (95% confidence interval (CI) 62-76%) at one year, 61% (95% CI, 52-67%) at five years, and 54% (95% CI, 45-62%) at 10 years. The one, five, and 10 year survival rates in the absence of cancer, cirrhosis, and mesenteric vein thrombosis were 95% (95% CI 87-98%), 89% (95% CI 78-94%), and 81% (95% CI 67-89%), respectively (n=83). Variables at diagnosis associated with reduced survival according to multivariate analysis were advanced age, malignancy, cirrhosis, mesenteric vein thrombosis, absence of abdominal inflammation, and serum levels of aminotransferase and albumin. The presence of variceal haemorrhage and myeloproliferative disorders did not influence survival. Only four patients died due to variceal haemorrhage and one due to complications of a portosystemic shunt procedure. CONCLUSION: We conclude that mortality among patients with EPVT is related primarily to concurrent disorders leading to EPVT and not to complications of portal hypertension.

Adolescent↗
PubMed2000

Factor V Leiden mutation, prothrombin gene mutation, and deficiencies in coagulation inhibitors associated with Budd-Chiari syndrome and portal vein thrombosis: results of a case-control study.

In a collaborative multicenter case-control study, we investigated the effect of factor V Leiden mutation, prothrombin gene mutation, and inherited deficiencies of protein C, protein S, and antithrombin on the risk of Budd-Chiari syndrome (BCS) and portal vein thrombosis (PVT). We compared 43 BCS patients and 92 PVT patients with 474 population-based controls. The relative risk of BCS was 11.3 (95% CI 4.8-26.5) for individuals with factor V Leiden mutation, 2.1(95% CI 0.4-9.6) for those with prothrombin gene mutation, and 6.8 (95% CI 1.9-24.4) for those with protein C deficiency. The relative risk of PVT was 2.7 (95% CI 1.1-6.9) for individuals with factor V Leiden mutation, 1.4 (95% CI 0.4-5.2) for those with prothrombin gene mutation, and 4.6 (95% CI 1.5-14.1) for those with protein C deficiency. The relative risk of BCS or PVT was not increased in the presence of inherited protein S or antithrombin deficiency. Concurrence of either acquired or inherited thrombotic risk factors was observed in 26% of the BCS patients and 37% of the PVT patients. We conclude that factor V Leiden mutation and hereditary protein C deficiency appear to be important risk factors for BCS and PVT. Although the prevalence of the prothrombin gene mutation was increased, it was not found to be a significant risk factor for BCS and PVT. The coexistence of thrombogenic risk factors in many patients indicates that BCS and PVT can be the result of a combined effect of different pathogenetic mechanisms.

Adult↗
PubMed2000

A survey of liver pathology in needle biopsies from HBsAg and anti-HBe positive individuals.

AIMS: To use laboratory data and liver biopsies, prospectively obtained from hepatitis B surface antigen (HBsAg) and anti hepatitis B e antigen (anti-HBe) positive patients, for the assessment of: (1) the relation between biopsy length/number of portal tracts and sampling error; (2) the relation between the severity of piecemeal necrosis and the new grading terminology (minimal, mild, moderate, and severe chronic hepatitis); and (3) liver pathology, which has not been studied in patients with this specific serological profile. METHODS: The study group (n = 174) included 104 patients with normal aminotransferase concentrations and no cases with clinically apparent cirrhosis. The specimen length and number of portal tracts were measured at light microscopy examination. Sampling error analysis was related to the discrepancies between aminotransferase concentrations versus histological grade. Detailed histological scorings were undertaken by the reference pathologist and compared with laboratory and hepatitis B virus (HBV) DNA precore sequence data. RESULTS: Sampling error seemed to be a constant feature, even for biopsies > or = 20 mm, but increased dramatically in biopsies < 5 mm long and/or containing less than four portal tracts. Between 25% and 30% of biopsies, graded as "mild" or "moderate" activity showed features of moderate and severe piecemeal necrosis, respectively. Ten per cent of the patients with normal aminotransferase values had stage III-IV hepatic fibrosis, and 20% had piecemeal necrosis. Only cytoplasmic, not nuclear, core antigen expression was a strong predictor of high hepatitis B viraemia. There was no association between precore stop codon mutations, grade/stage of liver disease, and hepatitis B core antigen (HBcAg) expression. CONCLUSIONS: The specimen available for light microscopical examination should be > 5 mm long and should contain more than four portal tracts. In addition, the new grading terminology might give the clinician an inappropriately mild impression of the severity of piecemeal necrosis. Furthermore, even in the presence of normal aminotransferase concentrations, considerable liver pathology can be found in 10-20% of HBsAg and anti-HBe positive individuals; such pathology is not associated with the occurrence of precore stop codon mutations.

Biopsy, Needle↗
PubMed1999

Evaluation of a novel bioartificial liver in rats with complete liver ischemia: treatment efficacy and species-specific alpha-GST detection to monitor hepatocyte viability.

BACKGROUND/AIMS: There is an urgent need for an effective bioartificial liver system to bridge patients with fulminant hepatic failure to liver transplantation or to regeneration of their own liver. Recently, we proposed a bioreactor with a novel design for use as a bioartificial liver (BAL). The reactor comprises a spirally wound nonwoven polyester fabric in which hepatocytes are cultured (40 x 10(6) cells/ml) as small aggregates and homogeneously distributed oxygenation tubing for decentralized oxygen supply and CO2 removal. The aims of this study were to evaluate the treatment efficacy of our original porcine hepatocyte-based BAL in rats with fulminant hepatic failure due to liver ischemia (LIS) and to monitor the viability of the porcine hepatocytes in the bioreactor during treatment. The latter aim is novel and was accomplished by applying a new species-specific enzyme immunoassay (EIA) for the determination of porcine alpha-glutathione S-transferase (alpha-GST), a marker for hepatocellular damage. METHODS: Three experimental groups were studied: the first control group (LIS Control, n = 13) received a glucose infusion only; a second control group (LIS No-Cell-BAL, n = 8) received BAL treatment without cells; and the treated group (LIS Cell-BAL, n = 8) was connected to our BAL which had been seeded with 4.4 x 10(8) viable primary porcine hepatocytes. RESULTS/CONCLUSIONS: In contrast to previous comparable studies, BAL treatment significantly improved survival time in recipients with LIS. In addition, the onset of hepatic encephalopathy was significantly delayed and the mean arterial blood pressure significantly improved. Significantly lower levels of ammonia and lactate in the LIS Cell-BAL group indicated that the porcine hepatocytes in the bioreactor were metabolically activity. Low pig alpha-GST levels suggested that our bioreactor was capable of maintaining hepatocyte viability during treatment. These results provide a rationale for a comparable study in LIS-pigs as a next step towards potential clinical application.

Animals↗
PubMed1999

Effects of a branched-chain amino acid-enriched diet on chronic hepatic encephalopathy in dogs.

A decreased ratio of branched-chain amino acids (BCAA) to aromatic amino acids (AAA) is considered an important pathogenetic factor in hepatic encephalopathy (HE). A relationship between the deranged BCAA/AAA ratio and dopaminergic dysfunction through the formation of "false" neurotransmitters has been postulated. The intermediate lobe of the pituitary is more pronounced in dogs than in humans and because it is primarily under dopaminergic inhibitory influence, it may serve as an indicator of alterations in dopaminergic neurotransmission. We investigated the effects of a diet with a high BCAA/AAA ratio (HR) and an isonitrogenous diet with a low BCAA/AAA ratio (LR) on several physical and biochemical parameters including pituitary function in dogs with portocaval shunts and 40% hepatectomy and in sham-operated pair-fed controls, in a double-blind, randomized cross-over study. Portocaval-shunted dogs had hyperammonemia (33+/-3 microM (mean +/- SEM) before and 214+/-21 after surgery)) and signs of HE. Their BCAA/AAA ratio in plasma and CSF decreased from 4.3+/-0.3 and 2.3+/-0.3 before surgery to 1.3+/-0.1 and 0.5+/-0.1 after surgery, respectively. These parameters remained unaltered in the control dogs. The consumption of the LR diet was significantly higher than consumption of the HR diet. In the portocaval-shunted dogs, plasma ammonia concentration was higher on the HR diet than on the LR diet (344+/-52 v 246+/-45) and the HE grade was worse. The BCAA/AAA ratio remained abnormal in HE dogs during the feeding of both diets. The basal and haloperidol-stimulated release of alpha-melanotropin and cortisol in plasma were not significantly different between or within groups during any period. In contrast, urinary cortisol excretion was increased in the HE dogs after surgery (urinary cortisol:creatinine ratio (x10(-6)) 8.5+/-1.4 before and 30.4+/-8.9 after surgery). The basal plasma concentration of adrenocorticotropin in HE dogs was decreased after surgery (68.3+/-10.2 ng/L before and 40.8+/-4.4 after surgery). This indicates a non-pituitary-dependent hyperresponsiveness of the adrenals. We conclude from these results that chronic HE in dogs is not associated with an abnormal dopaminergic neurotransmission at least at the level of the pituitary, and that it is not the content of the dietary neutral amino acids but rather the total protein intake that may have a beneficial effect on HE.

Adrenocorticotropic Hormone↗
PubMed1999

Combination therapy with mycophenolate mofetil and ursodeoxycholic acid for primary biliary cirrhosis.

Evidence of autoimmunity in primary biliary cirrhosis (PBC) provides a rationale for treatment with an immunosuppressant. Such a drug should be sufficiently free from serious toxicities to enable patients with asymptomatic, but progressive, disease to be treated longterm. Mycophenolate mofetil (MMF) mediates immunosuppression by selectively and reversibly inhibiting lymphocyte function, and has a more acceptable safety profile than other immunosuppressants that have been used in the treatment of this disease. Two patients, whose response to long-term treatment with ursodeoxycholic acid (UDCA) had been inadequate, were treated with a combination of MMF 2 g daily and UDCA 1 g daily for 12 months. In both patients this regimen was associated with no clinically significant adverse events, a decrease in elevated serum alkaline phosphatase levels to values close to the upper limit of normal, and an almost complete disappearance of the chronic inflammatory cell infiltrate that had been present in pre-combination treatment liver biopsies. MMF may be an appropriate immunosuppressive drug for use in the long-term treatment of patients with PBC, including asymptomatic patients.

Alkaline Phosphatase↗
PubMed1999

Significantly improved survival time in pigs with complete liver ischemia treated with a novel bioartificial liver.

Aim of the study was to evaluate treatment efficacy and safety of a scaled-up version of our porcine hepatocytes based BAL system in pigs with complete liver ischemia (LIS). Thirty-one pigs underwent total devascularization of the liver (LIS) by termino-lateral porta-caval shunts and sutures around the bile duct, the common hepatic and gastroduodenal arteries and their accessory branches. The hepato-duodenal ligament was completely transected. Four experimental groups were studied: the first control group (LIS Control, n = 10) received glucose infusion only, the second control group (LIS Plasmapheresis, n = 8) was connected to a centrifugal plasma-separator with a bottle representing the bioreactor volume, the third control group (LIS Empty-BAL, n = 5) received BAL treatment without cells, and the treated group (LIS Cell-BAL, n = 8) was connected for a maximum period of 24 hours to our scaled-up BAL seeded with around 14 billion viable primary porcine hepatocytes. BAL treatment significantly prolonged life in large animals (approximately 35 kg) with complete LIS (Controls, mean +/- SEM: 33.1 +/- 3 h, Cell-BAL: 51.1 +/- 3.4 h; p = 0.001; longest survivor 63 h). In addition, blood ammonia and total bilirubin levels decreased significantly, indicating metabolic activity of porcine hepatocytes in the bioreactor. No significant differences were noticed among the three control groups, indicating that there was no device effect and that the plasmapheresis procedure was well tolerated. No important adverse effects were observed.

Animals↗
PubMed1998

Relation between laboratory test results and histological hepatitis activity in individuals positive for hepatitis B surface antigen and antibodies to hepatitis B e antigen.

BACKGROUND: Hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B e antigen (anti-HBe) commonly coexist, and laboratory tests are often requested to assess histological hepatitis activity. An optimum panel of tests has not been found and the usefulness of hepatitis B virus (HBV) DNA assays in this context has not been established. We assessed various blood tests to find which best predicted hepatitis activity. METHODS: Routine plasma biochemical liver tests and serum HBV DNA (hybridisation and PCR assays) were assessed prospectively in 123 patients positive for HBsAg and anti-HBe. We scored histological hepatitis activity (hepatitis activity index) and determined whether chronic active hepatitis (chronic hepatitis with portal and periportal lesions) was present. We analysed the relation between laboratory data and the hepatitis activity index or risk of chronic active hepatitis by multiple regression and multiple logistic regression, respectively. FINDINGS: The analyses provided models for predicting either the hepatitis activity index or the risk of chronic active hepatitis. Aspartate aminotransferase was the most important test in the two models. The contribution of HBV DNA and other assays, especially alanine-aminotransferase activity, were of no practical importance. INTERPRETATION: Because screening by aspartate-aminotransferase activity could not be improved by the addition of other assays or HBV DNA, patients positive for HBsAg and anti-HBe could be screened for chronic active hepatitis with a single assay and counselling of patients can be improved if proper reference values are used.

Adult↗
PubMed1998

[Liver and artificial liver].

Despite good results of orthotopic liver transplantation in patients with fulminant hepatic failure the need still exists for an effective and safe artificial liver, able to temporarily take over the complex liver function so as to bridge the gap with transplantation or regeneration. Attempts to develop non-biological artificial livers have failed, mostly when controlled clinical trials were performed. In the last decade several different types of bioartificial livers have been devised, in which the biocomponent consists of freshly isolated porcine hepatocytes or a human hepatoblastoma cell line. The majority use semipermeable hollow fibers known from artificial kidney devices. The liver cells may lie either inside or outside the lumen of these fibers. In vitro analysis of liver function and animal experimental work showing that the bioartificial liver increases survival justify clinical application. Bioartificial livers are connected to patients extracorporeally by means of plasmapheresis circuit for periods of about 6 hours. In different trials about 40 patients with severe liver failure have been treated. No important adverse effects have not been reported in these phase I trials. Results of controlled studies are urgently needed. As long as no satisfactory immortalised human liver cell line with good function is available, porcine hepatocytes will remain the first choice, provided transmission of porcine pathogens to man is prevented.

Animals↗
PubMed1998

Changing patterns of gene expression in the pulmonary trunk-banded rat heart.

A pressure-overload model in the rat by banding the pulmonary trunk (PT) was developed to investigate alterations in gene expression in left- and right-ventricular compartments during the transition from compensated right-ventricular (RV) hypertrophy to right heart failure. Right heart failure in rat is characterized by liver cirrhosis, hydrothorax and ascites. The diameter of constriction was found to determine the time course of heart failure development. Only the RV free wall and the right atrium increased in weight, without a difference between compensated and failing RV. An increase in circulating ANP revealed a hypertrophic response of the myocardium, while increased circulating ammonia levels discriminated between compensated hypertrophy and failure. As parameters for stress, fibrosis and Ca2+-handling, changes in the pattern and level of the mRNAs encoding atrial natriuretic peptide (ANP), collagenIIIalpha1, and sarcoplasmic endoplasmic reticular calcium ATPase 2 (SERCA2), phospholamban (PLB) and calsequestrin (CSQ) were studied by Northern blot and in situ hybridization analyses. Pulmonary trunk banding resulted in an induction of ANP mRNA, a moderate increase in collagenIII alpha1 mRNA and a decrease in SERCA2 and PLB mRNA levels in both the left and right ventricles, but changes were most pronounced in the myocardium surrounding the RV cavity. Increased ammonia blood levels are a promising prognostic marker to detect the development of right heart failure.

Ammonia↗
PubMed1998

Changes in urinary taurine and hypotaurine excretion after two-thirds hepatectomy in the rat.

This study followed the time course of urinary taurine and hypotaurine excretion after two-thirds hepatectomy in rats. The excretion of both taurine and hypotaurine was elevated during 18 h following the hepatectomy, with maximal excretion during the first 6 h. Twelve and 24 h after partial hepatectomy, the hepatic hypotaurine concentration was increased but liver taurine did not differ significantly from controls. No changes were observed in hypotaurine and taurine concentrations of heart, kidney, lung, muscle tissue and spleen. We postulate that partial hepatectomy induces a rapid increase of hepatic (hypo)taurine synthesis from precursor amino acids. The increased (hypo)taurine concentrations spill over into urine.

Animals↗
PubMed1998

Efficacy of interferon dose and prediction of response in chronic hepatitis C: Benelux study in 336 patients.

BACKGROUND/AIMS: In an attempt to improve the limited efficacy of treatment of chronic hepatitis C with interferon-alpha 3 MU tiw, we studied the effects of double-dose therapy followed by downward titration, and analyzed the pre- and pertreatment factors associated with response or non-response. METHODS: Three hundred and fifty-four consecutive patients in 19 centers were randomized to interferon-alpha 3 MU tiw for 6 months or 6 MU tiw for 8 weeks followed by down-titration (3,1 MU tiw) till alanine aminotransferase remained normal and plasma HCV RNA was repeatedly undetectable. The primary outcome measure was sustained alanine aminotransferase and HCV RNA response 6 months after treatment. RESULTS: Three hundred and thirty-six patients received treatment. The sustained response rate for patients receiving 3 MU tiw for 6 months was 14% (9-21%,) and for patients receiving double dose tiw for 8 weeks and thereafter titrated therapy 15% (10-21%) (p=0.8). Pretreatment factors associated with a sustained alanine aminotransferase plus HCV RNA response were the absence of cirrhosis, presence of genotype 2 or 3, a low viral load and, in addition, a low alanine aminotransferase/aspartate aminotransferase ratio; a model was developed to allow estimation of the chance of response for the individual patient. The most powerful predictor of sustained response, however, was plasma HCV RNA at week 4; a positive test virtually precluded a sustained response (1.7%, 0.4-5.0%). If week 4 HCV RNA was not detectable, the chance of a sustained response was 21% (12-34%) for genotype 1 versus 40% (28-54%) for the others (p=0.02). Six MU tiw led to a significantly higher week 4 HCV RNA response (47% not detectable) than 3 MU (37%) (p=0.02). During down-titration this difference in viral on-treatment response was lost. CONCLUSIONS: In the treatment of hepatitis C, an early HCV RNA response is a prerequisite for long-term efficacy. Doubling the initial interferon dose increases this early response, but subsequent downward titration negates this effect, especially in genotype 1.

Adult↗
PubMed1998

Recovery from life-threatening, corticosteroid-unresponsive, chemotherapy-related reactivation of hepatitis B associated with lamivudine therapy.

Although exacerbations of previously quiescent HBV infection, associated with chemotherapy, have been attributed to enhanced immunological responses to hepatocytes harboring reactivated HBV, the recommended treatment, prednisolone, is often unsuccessful. A young HBsAg-positive, anti-HBe-positive carrier, who received chemotherapy for choriocarcinoma, developed icteric hepatitis. The serum HBV DNA level was 34,000 x 10(6) genomic equivalents per milliliter serum. Treatment with prednisolone alone did not prevent progression to overt hepatic failure. By three days after initiating lamivudine therapy, however, there was reversal of stage III hepatic encephalopathy. With further lamivudine treatment, substantial further improvement in hepatocellular function occurred and HBV-DNA levels became undetectable. When an immunocompromised patient develops an exacerbation of hepatitis B associated with high HBV DNA levels, treatment with prednisolone seems inappropriate, as hepatocytotoxic HBV replication may be stimulated further. In this situation inhibition of HBV replication, eg, by administering lamivudine, may be life-saving.

Adult↗
PubMed1998

Hepatitis C virus genotypes: epidemiological and clinical associations. Benelux Study Group on Treatment of Chronic Hepatitis C.

In a cohort of 292 chronic hepatitis C patients living in the Benelux countries the relationship between viral genotype and geographical origin, route of transmission, clinical characteristics and severity of liver disease was analyzed. HCV-RNA isolates could be classified by the Line Probe Assay (LiPA) as 1a, 1b, 2, 3, 4 or 5 in 286 (98%) cases. Patients of European origin were predominantly infected with HCV subtype 1b (164/254, 65%, CI 58-70%), as were patients of Asian origin (7/13, 54%). Patients originating from Surinam (South America) had predominantly type 2 (9/10, 90%), whereas Africans were mainly infected with type 4 (7/9, 77%). Blood transfusion was the mode of transmission in 142 (50%) patients, intravenous drug abuse (IVDA) in 40 (14%), occupational needle accident or tattoo in 11 (4%); no obvious source of infection was found in 93 (33%). In patients infected by blood transfusion, subtype 1b was predominant (70%, CI 61-77%), whereas subtypes la and 3 were predominant in those infected by IVDA (25% and 45%, respectively, p<0.001). Cirrhosis was observed in 68 (24%) patients; in multivariate analysis, factors independently related to cirrhosis were: the duration of infection, age and prior hepatitis B. No significant relationship was found between the severity of fibrosis or liver inflammation and the HCV (sub)types. In summary, in this large cohort of patients in the Benelux countries the hepatitis C virus (sub)type present was clearly related to the country of origin and the route of transmission, but not to the severity of liver disease.

Adult↗
PubMed1998

Commercially available media for flushing extracorporeal bioartificial liver systems prior to connection to the patient's circulation: an in vitro comparative study in two and three dimensional porcine hepatocyte cultures.

Extracorporeal bioartificial liver (BAL) systems based on hepatocytes need to be flushed before clinical application, as hepatocyte culture media are not approved for medical use. Commercially available 0.9% NaCl solution and hemofiltration solution (both supplemented with 10% human albumin) were investigated in vitro to test their potential to wash BAL systems with minimal stress for the cultured hepatocytes. After a 2 hour incubation, the lidocaine metabolising capacity and release of liver enzymes were assessed. As hepatocytes have been cultured in bioreactors in either two or three dimensional cell configurations, we tested the media in respectively hepatocyte monolayers cultures and in our newly developed bioreactor in which hepatocytes reorganise as small hepatocyte aggregates. The three dimensional hepatocyte cultures tolerated both media well, and no significant differences were seen compared with hepatocytes cultured in Williams' E (reference hepatocyte culture medium). The two dimensional hepatocyte cultures tolerated the supplemented hemofiltration solution and the reference medium equally well, but the condition of the porcine hepatocytes monolayer cultures was significantly impaired when incubated with the supplemented physiological saline solution. In conclusion, as a supplemented physiological saline solution may have detrimental effects on the condition of the hepatocytes, the more complex hemofiltration solution (bicarbonate buffered, glucose, essential minerals) was considered the better alternative for flushing bioartificial liver systems.

Animals↗