In hepatorenal syndrome (HRS), renal insufficiency is often progressive, and the prognosis is extremely poor under standard medical therapy. The molecular adsorbent recirculating system (MARS) is a modified dialysis method using an albumin-containing dialysate that is recirculated and perfused online through charcoal and anion-exchanger columns. MARS enables the selective removal of albumin-bound substances. A prospective controlled trial was performed to determine the effect of MARS treatment on 30-day survival in patients with type I HRS at high risk (bilirubin level, > or =15 mg/dL) compared with standard treatment. Thirteen patients with cirrhosis with type I HRS were included from 1997 to 1999. All were Child's class C, with Child-Turcotte-Pugh scores of 12.4 +/- 1. 0, United Network for Organ Sharing status 2A, and total bilirubin values of 25.7 +/- 14.0 mg/dL. Eight patients were treated with the MARS method in addition to hemodiafiltration (HDF) and standard medical therapy, and 5 patients were in the control group (HDF and standard medical treatment alone). None of these patients underwent liver transplantation or received a transjugular intrahepatic portosystemic shunt or vasopressin analogues during the observation period. In the MARS group, 5.2 +/- 3.6 treatments (range, 1 to 10 treatments) were performed for 6 to 8 hours daily per patient. A significant decrease in bilirubin and creatinine levels (P <.01) and increase in serum sodium level and prothrombin activity (P <.01) were observed in the MARS group. Mortality rates were 100% in the control group at day 7 and 62.5% in the MARS group at day 7 and 75% at day 30, respectively (P <.01). We conclude that the removal of albumin-bound substances with the MARS method can contribute to the treatment of type I HRS.

Liver failure associated with excretory insufficiency and jaundice results in an endogenous accumulation of toxins involved in the impairment of cardiovascular, kidney, and cerebral function. Moreover, these toxins have been shown to damage the liver itself by inducing hepatocellular apoptosis and necrosis, thus creating a vicious cycle of the disease. We report a retrospective cohort study of 26 patients with acute or chronic liver failure with intrahepatic cholestasis (bilirubin level > 20 mg/dL) who underwent a new extracorporeal blood purification treatment. A synthetic hydrophilic/hydrophobic domain-presenting semipermeable membrane (pore size < albumin size, 100-nm thick) was used for extracorporeal blood detoxification using dialysis equipment. The opposite side was rinsed with ligandin-like proteins as molecular adsorbents that were regenerated online using a chromatography-like recycling system (molecular adsorbent recirculating system [MARS]). Bile acid and bilirubin levels, representing the previously described toxins, were reduced by 16% to 53% and 10% to 90% of the initial concentration by a single treatment of 6 to 8 hours, respectively. Toxicity testing of patient plasma onto primary rat hepatocytes by live/dead fluorescence microscopy showed cell-damaging effects of jaundiced plasma that were not observed after treatment. Patients with a worsening of Child-TurcottePugh (CTP) index before the treatments showed a significant improvement of this index during a period of 2 to 14 single treatments with an average of 14 days. After withdrawal of MARS treatment, this improvement was sustained in all long-term survivors. Ten patients represented a clinical status equivalent to the United Network for Organ Sharing (UNOS) status 2b (group A1), and all survived. Sixteen patients represented a clinical status equivalent to UNOS status 2a, and 7 of these patients survived (group A2), whereas 9 patients (group B) died. We conclude that in acute excretory failure caused by a chronic liver disease, this treatment provides a therapy option to remove toxins involved in multiorgan dysfunction secondary to liver failure. (Liver Transpl 2000;6: 603-613.)

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Neutrophils are critical effector cells in humoral and innate immunity and play a vital role in phagocytosis and bacterial killing. If they and/or their specific functions are lacking, then immunoparalysis may occur, and severe diseases like systemic inflammatory response syndrome (SIRS) or sepsis can take a fatal course. In this paper, we discuss the possibility of using preconditioned cells in an extracorporeal biohybrid immune support system. A human promyelocytic cell line was stimulated for different times with all‐trans retinoic acid. The resulting cells displayed major signs and functions of mature neutrophilic granulocytes including oxygen radical production, phagocytosis of living and dead Escherichia coli, Staphylococcus aureus, Candida albicans, intracellular killing, and interleukin production. The cells can be expanded to yield a sufficient cell mass, and subsequent prestimulation results in an expression of specific neutrophil functions. Extracorporeal bioreactor experiments seem to be feasible to test the benefit in immunoparalysis‐associated diseases like SIRS or sepsis.

We describe a highly sensitive heterogeneous enzyme-linked immunoassay in which digoxin is used as the model analyte. An excess of enzyme-labeled monovalent antibody is incubated with sample containing the analyte such that all analyte is rapidly and quantitatively bound. Excess antibody that does not acquire a antigen in its binding site is rapidly removed from the mixture by passage through a porous affinity column containing immobilized analyte (or analog), present in vast excess. Only the labeled monovalent antibody that possesses an antigen in its binding site elutes from the column in the unbound fraction. The label present in this fraction is then quantified. Such an assay is extremely sensitive and obviates the limitations imposed by antibody affinity constants on homogeneous and competitive heterogeneous immunoassays. This assay can be performed rapidly and is readily amenable to automation.

Sodium dodecyl sulfate (NaDodSO4)--polyacrylamide gel electrophoresis and gel filtration chromatography of protein--NaDodSO4 complexes are frequently used to characterize collagen-like polypeptide components in mixtures obtained from extracts of basement membranes. However, electrophoresis yields anomalously high apparent molecular weights for collagenous polypeptides when typical globular proteins are used as molecular weight standards, and the use of gel filtration chromatography for this purpose was suspect because Nozaki et al. [Nozaki, Y., Schechter, N. M., Reynolds, J. A., & Tanford, C. (1976) Biochemistry 15, 3884--3890] found that asymmetric particles, including NaDodSO4--protein complexes, coeluted with native globular proteins of lower Stokes radius, when Sepharose 4B was used. To understand these effects and to improve the characterization of collagenous polypeptides, we investigated the secondary structure of NaDodSO4--collagen complexes with the use of circular dichroism, measured the NaDodSO4 content, studied the dependence of electrophoretic mobility on gel concentration, and extended work on gel filtration by use of a more porous gel, Sepharose CL-4B. We found that the anomalous behavior of collagen chains on NaDodSO4--polyacrylamide gel electrophoresis is due in large part to treatment of data and that the method can be used to determine rather accurate values for the number of residues per polypeptide chain. Our gel filtration results indicated that reliable molecular weights can be obtained when Sepharose CL-4B is used. These methods can be applied equally well to collagenous and noncollagenous polypeptides.

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