K.-H. Meyer zum Büschenfelde

In Vivo and in Vitro Binding of IgA to the Plasma Membrane of Hepatocytes

IgA bound in vivo was shown by immunofluorescence on the plasma membrane of isolated hepatocytes from subjects with normal liver and patients with liver cirrhosis, chronic active hepatitis or fatty liver. IgA in sera with elevated IgA concentrations, especially from cases with alcoholic cirrhosis, was bound in vitro to isolated hepatocytes from rabbit and mouse. This was not due to the high IgA concentration per se. Moreover, polyclonal polymeric serum‐type and secretory IgA, and three often polymeric monoclonal IgA preparations, showed similar binding properties. Conversely, purified polyclonal and monoclonal monomeric IgA did not show affinity for the hepatocytes. The binding of polymeric IgA did not seem to depend on the proportion of dimers and larger polymers, κ or λ‐type light chains, heavy‐chain subclasses, content of J chain or affinity for secretory component. The in vivo binding of IgA by hepatocytes is probably a physiological phenomenon which in part may explain the normal clearance of polymeric IgA from serum.

Anti-HBc, HBeAg and DNApolymerase activity in healthy HBsAg carriers and patients with inflammatory liver diseases

ZusammenfassungIn der vorliegenden Arbeit wird über anti-HBc-Titer-Bestimmungen, HBeAg, DNApolymerase-Aktivität im Serum sowie über intrazellulär nachweisbares HBcAg bei gesunden HBsAg-Trägern und Patienten mit HBsAg-positiven entzündlichen Lebererkrankungen berichtet.32/44 Patienten mit akuter Virus-B-Hepatitis hatten keine anti-HBc-Titer-Erhöhung in der ersten Krankheitswoche. Bei gesunden HBsAg-Trägern schwanken die anti-HBc-Titer zwischen 1:10 und 1:32000 (mittlerer Titer 1:4000). Bei HBsAg-positiven chronisch-aktiven Hepatitiden fand sich ein mittlerer Titer zwischen 1:32000 bis 1:64000, bei HBsAg-positiver CPH ein mittlerer Titer von 1:16000. Alle Patienten mit autoimmuner CAH (HBsAg-negativ) hatten anti-HBc-Titer unter 1:10.In einer Gruppe von 71 asymptomatischen HBsAg-Trägern konnten immunhistologisch bei keinem der gesunden HBsAG-Träger HBcAg im Leberzellkern nachgewiesen werden. Im Gegensatz dazu wurde HBcAg bei 4/5 HBsAg-positiven CAH- und 6/9 CPH-Patienten gefunden.Eine Erhöhung der DNApolymerase-Aktivität wurde bei keinem der gesunden HBsAg-Träger nachgewiesen. Von den 44 HBsAg-positiven akuten Virus-B-Hepatitiden hatten nur 3 Fälle eine Erhöhung der DNApolymerase-Aktivität. Andererseits fand sich eine DNApolymerase-Aktivität bei 17/37 Patienten mit HBsAg-positiver CAH und 9/15 Fällen mit CPH.Die Untersuchungen konnten eine enge Korrelation zwischen dem Nachweis des HBeAg im Serum und der DNApolymerase-Aktivität zeigen.Die Befundmuster ermöglichen eine klare Abgrenzung der “gesunden” HBsAg-Träger von den HBsAg-Trägern mit entzündlichen Lebererkrankungen.SummaryIn this paper we report on anti-HBc-titers, HBeAg, DNApolymerase activity in the serum and intracellular HBsAg in healthy HBsAg-carriers and patients with HBsAg-positive inflammatory liver diseases.32/44 patients with acure virus-B-hepatitis were negative for anti-HBc in the first week of the disease. Anti-HBc-titers in healthy HBsAg-carriers varied between 1:10 and 1:32,000 (medium titer 1:4,000). In HBsAg-positive CAH we found a medium titer between 1:32,000 and 1:64,000, in cases with CPH of about 1:16,000. All autoimmune type CAH showed anti-HBc-titers less than 1:10.By immunofluorescence we could demonstrate in a group of 71 asymptomatic HBsAg-carriers in none of the healthy HBsAg-carriers HBcAg in the liver cell nuclei. In contrast HBcAg could only be found in 4/5 HBsAg positive CAH- and 6/9 CPH patients.No elevated DNApolymerase activity could be demonstrated in healthy HBsAg-carriers. Out of 44 patients with virus-B-hepatitis only 3 showed elevated DNApolymerase activity. On the other hand DNApolymerase elevation was demonstrable in 17/37 cases with CAH and 9/15 with CPH.The investigations showed a strong correlation between the demonstration of HBeAg in the serum and the DNApolymerase activity.The characteristic findungs enabled us to differentiate between “healthy” HBsAg-carriers and HBsAg-carriers with inflammatory liver diseases.

Azodisalicylate (Azodisal Sodium) Causes Intestinal Secretion

Azodisalicylate (ADS) is one of the possible successors of sulfasalazine in the treatment of ulcerative colitis. The following results were obtained when comparing the influence of ADS on net water and electrolyte transfer in tied-off loops of the rat ileum and colon in vivo with sulfsalazine, 5-aminosalicylic acid, and sulfapyridine. (1) Sulfasalazine, 5-aminosalicylic acid and sulfapyridine had no effect on water and electrolyte transfer of the healthy intestinal mucosa in concentrations up to 400 mg%. (2) ADS showed a concentration-dependent inhibition effect on net water, sodium and chloride absorption and stimulated secretion at concentrations higher than 100 mg%. (3) No morphological alterations of the mucosa could be observed by light and transmission electron microscopy. The observed effect of ADS might have some clinical significance in patients with a decreased absorptive capacity of the colon in ulcerative colitis, in contrast to healthy volunteers, where the high absorptive capacity of the colon might compensate the decreased absorption or stimulated secretion in the small intestine.

Spontaneous cell-mediated (SCMC) and antibody-dependent cellular cytotoxicity (ADCC) in patients with acute and chronic active hepatitis

SummarySpontaneous (SCMC) and antibody-dependent (ADCC) cellular cytotoxicity was studied in patients with acute viral hepatitis B and chronic active hepatitis (CAH) B and non-A, non-B. Chang cells displaying the liver-specific protein LSP on the plasma membrane were used as target cells. SCMC and ADCC in acute hepatitis B were not different from normal controls. SCMC and ADCC in chronic active hepatitis B as well as in non-A, non-B were significantly elevated in comparison to normal controls. In additional experiments, the influence of patients sera on SCMC and ADCC was studied. Autologous serum from CAH patients significantly reduced cytotoxicity in SCMC and ADCC assays. This inhibitory capacity of patients sera was attributable to immune complexes, as ultracentrifugation studies and determination of immune complexes of fractionated sera demonstrated.ZusammenfassungSpontane (SCMC) und antikörperabhängige (ADCC) zelluläre Zytotoxizität wurde bei Patienten mit akuter Virushepatitis B und Patienten mit chronisch aktiver Hepatitis Typ B und Typ non-A, non-B untersucht. Chang-Zellen, die auf der Zellmembran das leberspezifische Protein LSP aufwiesen, wurden als Zielzellen benutzt. SCMC und ADCC bei Patienten mit akuter Virushepatitis B unterschieden sich nicht von den Kontrollen. SCMC und ADCC bei Patienten mit chronisch aktiver Hepatitis Typ B und Typ non-A, non-B waren signifikant im Vergleich zu Normalpersonen erhöht. In weiteren Experimenten wurde der Einfluß von Patientenserum auf SCMC und ADCC untersucht. Autologes Patientenserum von CAH-Patienten inhibierte signifikant SCMC und ADCC Experimente. Die inhibitorischen Faktoren in Patientenseren konnten auf Immunkomplexe zurückgeführt werden, wie Fraktionierung von Seren und die Bestimmung zirkulierender Immunkomplexe zeigte.

IgM antibody to hepatitis B core antigen (anti-HBc IgM) in “healthy” HBsAg carriers: A longitudinal study of 75 cases

SummaryIn 75 healthy HBsAg carriers with normal liver tissue who were followed over a four years period, anti-HBc IgM was determined by ELISA. 61 HBsAg carriers (81%) were positive for anti-HBc IgM at first investigation. 54 individuals demonstrated persistence of anti-HBc IgM, 7 became anti-HBc IgM-negative within the observation period. 12 persons were persistent anti-HBc IgM-negative, and 2 developed anti-HBc IgM of low quantities. 3 of 4 individuals with HBsAg clearance demonstrated a considerable decrease of anti-HBc IgM concentration. Although signs of liver damage or development of chronic liver diseases were not observed at the time of control biopsy the existence of anti-HBcIgM indicates that there exists also in healthy HBsAg carriers a persistent stimulation by HBcAg, inducing the production of anti-HBc IgM as a sign of permanent ongoing virus B replication. These results require a new and critical review of the “healthy” HBsAg carrier state.ZusammenfassungBei 75 gesunden HBsAg-Trägern mit bioptisch normalem Lebergewebe, die über einen Zeitraum von 4 Jahren beobachtet wurden, wurde anti-HBc IgM mit der ELISA-Technik bestimmt. Anti-HBc IgM fand sich bei der Erstuntersuchung bei 61 HBsAg-Trägern (81%). 54 Personen blieben anti-HBc IgM positiv, 7 wurden negativ. Bei 12 HBsAg-Trägern war von Anfang an kein anti-HBc IgM nachweisbar, und bei 2 Personen fanden sich erst bei der Kontrolluntersuchung geringe Mengen von anti-HBcIgM. 3 von 4 HBsAg-Trägern, die innerhalb des Beobachtungszeitraumes HBsAg aus dem Serum eliminerten, zeigten einen deutlichen Abfall der anti-HBc IgM-Konzentration oder wurden anti-HBc IgM negativ. Obwohl eine Verschlechterung des morphologischen Leberbefundes oder die Entwicklung einer chronischen Leberentzündung bei der Kontrollbiopsie nicht beobachtet wurde, muß aufgrund des positiven Nachweises von anti-HBc IgM bei gesunden HBsAg-Trägern angenommen werden, daß auch bei diesen Personen eine ständige aktive Virus B Replikation stattfindet. Diese Ergebnisse erfordern eine kritische Neubewertung des “gesunden” HBsAg-Trägerstatus.

Antigenic relationship between Chang liver cells and human hepatocytes

ZusammenfassungMit Hilfe monospezifischer Antiseren gegen menschliches lebermembranspezifisches Protein (LSP) konnte gezeigt werden, daß Chang Leberzellen LSP auf der Zellmembran besitzen. Chang Leberzellen können daher als in vitro System zur Untersuchung immunologischer Reaktionen gegen LSP in menschlichen entzündlichen Lebererkrankungen benutzt werden.SummaryUsing monospecific antisera against human liver specific protein (LSP) it could be demonstrated that Chang liver cells bear LSP on their membranes. Chang liver cells can therefore be used as in vitro system to study immune reactions against LSP in human inflammatory liver diseases.

Is the Bile Duct Diameter a Reliable Parameter to Diagnose Extrahepatic Cholestasis

The common bile duct (CBD) pressure was determined in 57 patients before endoscopic retrograde cholangiography (ERC) and related to the diameter of the CBD and the common hepatic duct (CHD). We found that despite a weak overall positive correlation in the individual patient, CBD or CHD diameters do not correlate with CBD pressure. In patients without extrahepatic cholestasis and normal CBD pressure, both CBD and CHD diameters were measured in a wide range between 5 and 32 mm. Extrahepatic cholestasis due to distal CBD obstruction is reflected by a high CBD pressure, but cannot be identified reliably by measuring the CBD diameter which is found within the range of patients not obstructed. In cholecystectomized patients, CBD and CHD are significantly (p less than 0.005) wider than in non-cholecystectomized patients (8.8 +/- 1.0 vs. 13.3 +/- 1.2 and 9.2 +/- 0.9 vs. 14.2 +/- 1.2 mm, respectively). The CBD pressure, however, is nearly identical in both groups. It is concluded that the assessment of CBD and CHD diameter is not a reliable parameter for the diagnosis of extrahepatic cholestasis which--in certain cases--could be proved by endoscopic retrograde manometry.

Long-Term Follow-Up of Patients with Chronic Hepatitis C after Interferon-Alpha Treatment

In this study, 72 patients with chronic hepatitis C virus (HCV) were followed prospectively for a mean period of 27 months after interferon treatment. Fifty-seven percent (20/35) of the patients with complete response, 18/20 with HCV-RNA-negative serum, had a sustained biochemical remission. Reactivation was seen in 43% of these patients after a mean follow-up of 7.3 months. A late relapse after more than 12 months of follow-up occurred in only 2/15 patients. Patients with a long-term complete response had significantly lower pretreatment serum HCV RNA levels than complete responders with relapse (106,239 vs. 345,649 mEq/ml, p = 0.0213). A delayed sustained biochemical remission was seen in 3/37 patients with partial or no response. Thus, long-term response is achieved in 32% of the patients treated with interferon, clearly associated with a suppression of serum HCV RNA. Patients with normal ALT values and undetectable levels of HCV RNA for more than 12 months of follow-up may usually be considered as sustained responders. Thus, for the first time, the pretreatment HCV RNA level in serum was identified as predictive of long-term response.

Inhibition of hepatitis B virus specific DNA polymerase by intercalating agents

Intercalating agents, some of them in clinical use, were tested for their ability to inhibit the hepatitis B virus specific DNA polymerase reaction. Ethidium bromide was shown to be the strongest inhibitor among the compounds tested. Compounds in clinical use inhibited the DNA polymerase test only at high concentrations. The inhibitory activity of all compounds tested was increased when the MgCl2 content in the reaction mixture was lowered. UV absorption studies presented no evidence that this effect was due to complex formation of magnesium and the individual compounds. The therapeutic significance of these findings is not certain and needs further work.

Detection of circulating immune complexes with a modified Raji cell technique.

ZusammenfassungEine Modifikation der Raji-Zell-Technik zum Nachweis zirkulierender Immunkomplexe wird beschrieben. Lymphoide Raji Zellen binden Immunkomplexe durch einen C 3 Rezeptor. Vor Inkubation mit dem Testserum ist es erforderlich, den IgG Fc Rezeptor zu blockieren, der andernfalls mit dem Immunkomplexnachweis interferieren würde. In der hier beschriebenen Methode wird der IgG Fc Rezeptor mit isoliertem IgG Myelomprotein blockiert mit Nachweis von C 3 Rezeptor gebundenen Immunkomplexen mit Fluoreszein-konjugierten Anti-Leichtkettenseren. Diese Modifikation wird gegenwärtig in größeren Kollektiven von Patienten mit verschiedenen Autoimmunerkrankungen benutzt.SummaryA modification of the Raji cell technique for the detection of circulating immune complexes is described. Raji lymphoid cells bind immune complexes via the C 3 receptor. Prior to incubation with the test serum it is necessary to block the IgG Fc receptor which would interfere with the assay. In the present modification the IgG Fc receptor is blocked with monoclonal IgG myeloma proteins thereby facilitating the detection of C 3 bound immune complexes with fluorescein-conjugated anti-light chain serum. This modification is presently used in a survey of immune complexes in a number of autoimmune diseases.