Yoshio Mori

Effect of glycyrrhizin on lysis of hepatocyte membranes induced by anti‐liver cell membrane antibody

Studies were made on why glycyrrhizin injection decreases the plasma aspartate aminotransferase (AST) and alanine aminotransferase activities in patients with chronic hepatitis.1 For this, rat hepatocytes were isolated, and incubated with antibody raised against rat liver cell membranes, and the effect of glycyrrhizin on their release of transaminase was investigated. Isolated rat hepatocytes released AST on incubation with anti‐liver cell antibody in the presence of complement. At this time, their endogenous phospholipase A2 activity was increased. Cultured hepatocytes also released the transaminase in the presence of venom phospholipase A2. Glycyrrhizin suppressed the release of transaminase in the presence of either anti‐liver cell membrane antibody or phospholipase A2. These results suggest that antibody treatment raised the phospholipase A2 activity in liver cell membranes, resulting in release of transaminases, and that glycyrrhizin suppressed this increase in phospholipase A2 activity and so inhibited the release of transaminase.

Study on chronic renal injuries induced by carbon tetrachloride : selective inhibition of the nephrotoxicity by irradiation

Carbon tetrachloride (CCl4) was intraperitoneally injected into Balb/c mice 4 times at biweekly intervals, and the morphological changes of the liver and kidney were examined during 12 weeks after the last injection. The renal injuries progressed in spite of cessation of CCl4 treatment; microcysts with tubular-cell degeneration were manifest on day 42 after the last injection of CCl4. At the end of the experiment, however, interstitial fibrosis with inflammatory cell infiltration was much more prominent. Glomerular changes with IgG deposits also developed following the tubulointerstitial changes. The CCl4 treatment induced liver damage as well, but it promptly subsided without formation of cirrhosis. The CCl4 nephrotoxicity was completely inhibited by whole body irradiation (200 rad) exposed at each injection of CCl4. In contrast, the hepatic damage was not changed by irradiation. These results seem to indicate etiologic independence of renal and hepatic events induced by CCl4 treatment. It is also suggested that chronic CCl4 nephrotoxicity is mediated, at least in part, by radiosensitive responses of the mice themselves.

Inhibitory effects of prostaglandin E1 on T-cell mediated cytotoxicity against isolated mouse liver cells

The effects of prostaglandin E1 on cell-mediated cytotoxicity against hepatocytes were investigated using an in vitro cytotoxic assay system. Isolated liver cells from normal C57BL/6 mice were used as the target cells, and effector cells were obtained from spleens of C57BL/6 mice in which experimental hepatitis had been induced by immunization with syngeneic liver antigens. In this assay system, spleen T cells adhering to nylon wool demonstrated a high cytotoxic activity against target liver cells. The cytotoxicity was markedly reduced by prostaglandin E1 at concentrations greater than 10(-7) M. Maximum suppressive activity was obtained when prostaglandin E1 was continuously present during the assay period. By contrast, indomethacin, a specific inhibitor of prostaglandin synthesis, enhanced the cytotoxic activity of effector cells. These data seem to indicate that exogenously added prostaglandin E1 has an inhibitory effect on cell-mediated cytotoxicity of effector spleen cells against target hepatocytes.

Autoimmune interstitial disease of the kidney and associated antigen purification and characterization of a soluble tubular basement membrane antigen

Abstract A soluble tubular basement membrane (TBM) antigen has been purified from human kidneys by a combination of immunochemical and physicochemical procedures. Its chemical properties were entirely different from those of glomerular basement membrane (GBM) antigen as studied by DEAE-cellulose chromatography and electrophoresis. The molecular weight of TBM antigen was estimated to be 30,000 daltons and that of GBM 40,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified TBM antigen did not cross-react with GBM antigen and cross-reacted with the TBM antigen similarly purified from other animals such as goats, guinea pigs, and mice in immunodiffusion plates. Goats and some mice immunized with the purified human TBM antigen developed a typical interstitial nephritis. The goat sera stained the basement membrane of normal tubules and Bowmanns capsules, and no anti-GBM activity was detected in the serum by immunofluorescence. The system provides a simple and useful model of interstitial nephritis produced with a purified TBM antigen.

Pneumothorax in a patient with Wegener's granulomatosis during treatment with immunosuppressive agents

Abstract. We present the case of a 16‐year‐old woman with Wegeners granulomatosis, who developed a pneumothorax while receiving treatment with cyclophosphamide and glucocorticoids. The lung was re‐expanded by tube drainage, and the patient recovered completely while the immunosuppressive treatment was continued in combination with sulphamethoxazole‐trimethoprim. A possible role for this antimicrobial drug in the treatment of Wegeners granulomatosis is briefly discussed.

Suppressor system in murine interstitial nephritis: analysis of tubular basement membrane (TBM)-specific suppressor T cells and their soluble factor in C57BL/6 mice using a syngeneic system

We induced typical interstitial nephritis with high titers of anti-tubular basement membrane (TBM) autoantibody in genetically resistant C57BL/6 mice by treating them with sodium aurothiomalate (gold) and immunizing them with syngeneic TBM antigen. When gold was not used, the T-cell fraction of nylon wool adherent splenic cells showed prominent suppressive activity against the proliferative response of nonadherent cells to TBM antigen. However, this suppressive activity was remarkably decreased by the gold treatment. TBM antigen sensitized thymocytes, a thymocyte extract, and a spleen cell extract were transferred to C57BL/6 mice which had been immunized with TBM antigen and treated with gold. This transfer clearly depressed the induction of autoimmune interstitial nephritis in an antigen-specific manner. These results indicate that TBM antigen-specific suppressor T cells and their soluble factor may play an important role in the negative regulation of interstitial nephritis in C57BL/6 mice.

Liver-specific F antigen in the serum of patients with liver diseases and the detection of early stage hepatocellular carcinoma

Liver-specific F antigen was detected in serum using human-specific guinea pig antiserum, in 75 out of 121 patients with various liver diseases. The antigen was detectable in most of the patients (86.7%) with hepatocellular carcinoma, and the levels of F antigen were often high in these patients. There was no correlation between the levels of F antigen and alpha-fetoprotein. Temporal changes of serum F antigen level were also studied in patients with hepatocellular carcinoma. In 8 out of 13 patients with hepatocellular carcinoma, serum F antigen level remained continuously high, and in these patients, it had been significantly high for several months to one year before hepatocellular carcinoma became clinically detectable. Extracts of hepatocellular carcinomas obtained by necropsy was examined for the presence of F antigen, and it was found that most of hepatocellular carcinomas contained the human-specific determinant of F antigen, but lacked the species non-specific determinant of the antigen. The use of human-specific anti-F antiserum may facilitate early detection of hepatocellular carcinoma in some patients.

Gold Nephropathy — Effect of Gold on Immune Response to Renal Tubular Basement Membrane (TBM) Antigen in Mice

Renal injuries that follow administration of gold salt in the treatment of rheumatoid arthritis are well recognized (1,2). Changes are seen distributed both in the glomerular and tubular regions studied by light and electron microscopy (1,2). Using guinea pigs, we have reported that injection of gold produces tubulointerstitial nephritis with positive anti-renal tubular basement membrane (TBM) autoantibody and immune complex nephropathy with positive anti-renal tubular epithelial (RTE) autoantibody (3) . It is of interest that autoimmune diseases are induced by gold treatment. Measel (4) reported that gold not only had an immunosuppressive effect but also an immunoenhancing effect, depending on dosage. Lando et al. (5) reported that appropriate low doses of cyclophosphamide induce encephalomyelitis in genetically resistant mouse strains, suggesting that low doses cyclophosphamide deletes activity of suppressor T cells. With the assumption that an appropriate dose of gold would have the same effect as cyclophosphamide, we attempted to induce interstitial nephritis (IN) in genetically resistant C57BL/6 (6) mice by pretreatment with gold and immunization with syngeneic TBM antigen in complete Freund’s adjuvant. We also studied the effect of gold on immune response to TBM antigen and on development IN in high responder BALB/c mice.

Protective effects of FUT-175 on acute massive hepatic necrosis induced in mice following endotoxin injection and immunization with liver proteins

Experimental autoimmune hepatitis was induced in C57BL/6 mice by immunization with syngeneic liver protein and adjuvant. Hepatitis was characterized by marked cellular infiltrates, but hepatic necrosis was mild to moderate. A small dose of endotoxin (25 micrograms/mouse) produced lethal hepatitis with elevation of serum transaminase levels in these mice. The endotoxin-induced reactions were completely inhibited by i.p. administration of FUT-175 (5 mg/kg), a synthetic protease inhibitor, 1 h before the endotoxin injection. In vitro experiments showed that two-thirds of the inflammatory infiltrates were monocyte/macrophages. Cytotoxicity against syngeneic hepatocytes was significantly increased by the addition of endotoxin (25 micrograms/ml), but the same dose of endotoxin alone had no effect on the viability of hepatocytes. The endotoxin-induced increase in cytotoxicity was prominent in the glass-dish adherent (monocyte/macrophage enriched) fraction and was also demonstrated after depletion of T-cells. However, elevated cytotoxicity did not occur when FUT-175 (> 1 x 10(-7) M) was present throughout the assay period. These results seem to indicate that the hepatotoxic effects of endotoxin are mediated, at least in part, by monocytes or macrophages infiltrating the liver following immunization of liver proteins. Our results also suggest that FUT-175 has protective effects against endotoxin-induced hepatotoxic reactions.

Abstracts of Selected Papers Presented at the 76th General Meeting of the Japanese Society of Gastroenterology

S OF SELECTED PAPERS PRESENTED AT THE 76TH GENERAL MEETING OF THE JAPANESE SOCIETY OF GASTROENTEROLOGY March 29-31, 1990, Tokyo, Japan Chairman: Haruo KAMEDA, M.D.