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To assess whether peripheral blood mononuclear cells (PBMCs) can be substituted for liver tissue in monitoring the hepatic expression of interferon receptors (IFNAR1 and/or IFNAR2) in chronic hepatitis C, we quantified the mRNA of both subunits, using the competitive polymerase chain reaction, in the liver specimens from 37 chronic hepatitis C patients and in PBMCs from 29 of 37 patients. PBMCs from 10 healthy subjects were also quantified for both subunits. Hepatic expression of IFNAR1 and IFNAR2 were more frequent than PBMCs: IFNAR1, 23/27 (85%) vs 7/19 (37%), P = 0.0021, IFNAR2, 34/37 (92%) vs 19/29 (66%), P = 0.0182. Neither subunits was detected in PBMCs from control subjects. The expression level of IFNAR2 in the liver was related to that in PBMCs (r = 0.613, P = 0.0052). These results suggest that hepatitis C virus infection may up-regulate the expression of the type I interferon receptor and that the measurement of IFNAR2 expression in PBMCs may be useful for monitoring its expression in liver.

The aim of the study was to investigate the effect of the immunosuppressant FK 506 (tacrolimus hydrate) on acute liver injury induced by Propionibacterium acnes and lipopolysaccharide (LPS). Acute liver injury was induced in male Wistar rats by injecting the animals with P. acnes (10 mg/rat), and administering LPS (10 microg/rat) seven days later. One group was given FK 506 (1 mg/kg) 24 and 2 hr before administration of LPS, and the other group was given the same dose of saline. The 24-hr survival rate, serum alanine aminotransferase (ALT) concentration, and tumor necrosis factor (TNF) -alpha mRNA and protein concentrations in the liver and spleen were then compared. Hepatic macrophages were also isolated from rats seven days after P. acnes injection, LPS, and FK 506 or saline were added to the culture supernatant, and TNF-alpha production was studied. The 24-hr survival rate was 100% in the FK 506-treated group, in contrast with 16.6% in the saline group. Four hours after LPS injection, the serum ALT concentration was 755 +/- 401 in the saline group versus 119 +/- 42 units/ml (P < 0.01) in the FK 506-treated group. The serum TNF-alpha concentration was lower in the FK 506-treated group (1,419 +/- 957 pg/ml) than in the saline group (9205 +/- 2215) (P < 0.01). The mRNA and protein concentrations in the liver and spleen in the two groups did not differ significantly 1 hr after LPS injection but were significantly lower in the FK 506-treated group after 4 hr. FK 506 did not directly inhibit TNF-alpha production by isolated cultured hepatic macrophages. FK 506 is unable to inhibit initial TNF-alpha production by hepatic macrophages (or probably that by splenic macrophages either) stimulated by injection of LPS in P. acnes + LPS-induced acute liver injury. However, the immunosuppressant does limit hepatic damage by inhibiting subsequent aggravation of inflammation by the cytokine network.

The aim of this study was to investigate the association of stellate cell activation with serum fibrosis markers in a rat model of hepatic fibrosis prepared using a choline-deficient L-amino acid (CDAA) defined diet. CDAA diet administration resulted in increased liver hydroxyproline contents in a time-dependent manner with activated stellate cells, expressing alpha-smooth muscle actin (alpha-SMA) as well as increased serum concentrations of amino-terminal procollagen type III peptide (PIIIP) and the 7S fragment of type IV collagen. Hydroxyproline content of the liver showed a closer correlation with the serum 7S (r = 0.75, P < 0.01) concentration than with the serum PIIIP (r = 0.51, P < 0.01) concentration. The percent area of alpha-SMA-positive cells showed stronger correlation with the serum PIIIP concentration (r = 0.85, P < 0.01) than with the 7S concentration (r = 0.50, P < 0.01). These results indicate that the serum PIIIP concentration reflects the activity of fibrogenesis, while the serum 7S concentration reflects the accumulation of collagen fibers in the liver.

To determine the transmission route of Helicobacter pylori, one nude mouse was challenged by H. pylori, and then raised with nonchallenged nude mice in a single cage in a sterilized environment with and without exposure to their feces. After coraising for two and four weeks, all mice were killed to determine H. pylori in the stomach, saliva, and feces and to assess gastritis grade. Natural transmission of H. pylori occurred in 50% (2/4) and 70% (7/10) of mice after two weeks and four weeks of coraising when they were exposed to their feces. H. pylori was detected not only in the stomach but also in saliva and feces by PCR of all challenged and transmitted mice. However, no transmission occurred in mice not exposed to feces of a challenged mouse, while sharing food and water in a single cage. These findings suggest that the fecal-oral transmission route is important, at least in the animal model. Serum levels of anti-H. pylori urease IgG of the H. pylori-transmitted mice increased after coraising, and gastritis was observed in the stomach of both challenged and transmitted mice. We conclude that H. pylori bacteria are transmitted through the fecal-oral route from challenged to nonchallenged nude mice, resulting in gastritis.

Injection of pig serum into rats twice a week for eight weeks induced transforming growth factor-beta1 (TGF-beta1) mRNA expression and protein production resulting in liver fibrosis without parenchymal cell injury. Eight-week treatment with pig serum reduced bromodeoxyuridine (BrdU) -positive hepatocytes 24 hr after 70% partial hepatectomy compared to that in the livers of rats treated with saline for eight weeks. Administration of a choline-deficient L-amino acid-defined (CDAA) diet for six weeks with pig serum coadministration, after pretreatment with pig serum for eight weeks, led to the development of preneoplastic lesions that were positive for the placental form of glutathione S-transferase (GSTP). Eight-week pretreatment with pig serum induced more GSTP-positive lesions and TGF-beta1 mRNA expression and protein concentration in the livers of rats subsequently fed a CDAA diet for six weeks than in rats fed the CDAA diet with saline treatment. These results indicate that TGF-beta1 induced by pig serum treatment inhibited hepatocyte proliferation but failed to prevent the development of preneoplastic lesions in a CDAA diet model.

The aim of this study was to investigate whether an iron chelator, deferoxamine (DFO) can prevent lipid peroxidation, resulting in reduced liver injury as well as reducing preneoplastic lesions induced by a choline-deficient L-amino acid-defined (CDAA) diet. CDAA diet administration resulted in an increased serum ALT level (367 +/- 58) after two weeks, but simultaneous DFO treatment for two weeks reduced this elevation of ALT as well as malondialdehyde (MDA) production in the liver. Feeding rats a CDAA diet for 12 weeks led to the development of severe liver fibrosis and preneoplastic lesions detected as enzyme-altered lesions. DFO treatment prevented the expression of activated stellate cells, resulting in the reduction of liver fibrosis as well as reducing the development of preneoplastic lesions. These results indicate that iron chelation can reduce the development of preneoplastic lesions in a CDAA diet model.

Recent studies have suggested an association between tumor necrosis factor-alpha (TNF-alpha) and the development and progression of acute liver failure. To investigate the role of TNF-alpha in the mechanism of massive hepatic necrosis, we studied a mouse model of TNF-alpha and D-galactosamine (GalN) -induced hepatic necrosis by ultrastructural analysis. Administration of GalN caused edema of hepatocellular microvilli and widening of sinusoidal endothelial fenestrae (SEF); administration of TNF-alpha caused only a widening of the SEF. Massive hepatic necrosis with hemorrhage was seen 6 hr after concomitant administration of TNF-alpha and GalN. In the ultrastructural analysis, edema of the hepatocellular microvilli, widening of the SEF, and transmigration of red blood cells (RBC) and platelets to the space of Disse without exfoliation and necrosis of the sinusoidal endothelial cells were observed. Fibrin deposits were seen in areas adjacent to injured hepatocytes. The diameter of the SEF was significantly greater than in the nontreated group and the groups treated with TNF-alpha or GalN alone. These results suggest that as a consequence of the increase in diameter of the SEF, transmigration of RBCs and platelets to the space of Disse may have resulted in massive hepatic necrosis due to occlusion of the microcirculation.

Conventional cytogenetic studies have demonstrated frequent abnormalities of specific chromosomes in hepatocellular carcinoma, although there are few reports examining the relationship between chromosomal aberrations and clinicopathologic features. In this study, numerical aberrations of chromosomes 16, 17, and 18 were examined by fluorescence in situ hybridization using pericentromeric DNA probes in 20 cases of surgically removed hepatocellular carcinoma. DNA ploidy analysis was also performed by flow cytometry. Numerical abnormalities of chromosomes 16, 17, and 18 were found in 7 of 19 cases, 15 of 20 cases, and 12 of 20 cases, respectively. Gain and/or loss of more than one chromosome was detected in 16 of 19 cases. However, aneuploidy was seen in only 9 of 20 tumors by flow cytometry. The incidence of aneusomy 17 and 18 increased with tumor size and stage progression. Fluorescence in situ hybridization analysis demonstrated that numerical chromosomal aberrations accumulated with tumor progression in hepatocellular carcinoma.

Hepatitis C virus (HCV) circulates as particles having differing buoyant densities. Changes in the relative proportions of virus particles of different densities were examined in 19 patients with chronic hepatitis C: 6 without (group A) and 13 with (group B) abnormal serum alanine aminotransferase (ALT) levels. High- and low-density virus particles were separated by differential flotation centrifugation. The numbers of high-density particles consistently exceeded that of low-density particles in all patients in group A, whereas the titers of both types of particles were the same at least once in 7 of 10 patients sampled at two time points in group B. The ALT level significantly increased <2 months later (P < 0.05) when the titers of both types of particles were the same in patients in group B. Thus, we found a correlation between the relative numbers of circulating low-density HCV particles and disease activity in chronic hepatitis C patients.

To assess the relationship between hepatitis C virus infection and Fas antigen expression on hepatocytes, we examined changes in hepatic Fas antigen expression in the presence or absence of active hepatitis C virus infection. Twenty patients with chronic hepatitis C infection were treated with interferon and underwent pre- and posttreatment liver biopsies. Patients were classified according to the absence (group A; n = 9) or the presence (group B; n = 11) of hepatitis C virus RNA (HCV-RNA) in the liver after interferon therapy. An immunohistochemical assay showed Fas antigen staining in hepatocytes membranes and cytoplasm with expression concentrated mainly in periportal areas. The percentage of Fas-positive cells in the liver before treatment was not different between group A (39.5+/-19.1%) and group B (32.5+/-15.6%). Hepatic Fas expression was reduced significantly after treatment (24.3+/-10.6%) compared with the pretreatment values in group A (p < 0.05) but not in group B (25.9+/-16.9%). There was no significant difference between the two groups in the degree of histologic improvement. These results suggest that hepatic Fas expression is associated with persistent infection of hepatitis C virus.

Two daughters born to an HBeAg-positive carrier became hepatitis B virus carriers despite immunoprophylaxis with hepatitis B immune globulin or hepatitis B vaccine. The elder daughter received hepatitis B immune globulin alone and the younger daughter received both hepatitis B immune globulin and hepatitis B vaccine. They acquired anti-HBs passively immediately after birth, and the younger daughter did not respond to active immunization. The nucleotide sequence of the S gene of hepatitis B virus DNA from the four carriers in the family was determined. A 531-bp fragment within the S gene, which includes a region encoding both the common a and type-specific d/y or r/w determinants, was amplified by polymerase chain reaction and sequenced. Antigenic subtypes of HBV were identified as adr in the father and adw in both the mother and two daughters. Amino acid residues 122-160 of HBsAg were identical between the daughters and their mother except for a glycine-to-arginine substitution at codon 145. A possibility that this escape mutant had selective advantage over wild-type hepatitis B virus under immune pressure is discussed.

To determine whether the loss of serum hepatitis C virus RNA (HCV-RNA) early in interferon therapy would indicate a sustained response to this agent, we detected serum HCV-RNA successively during and after therapy. Serum samples for detection of HCV-RNA were obtained serially from 36 patients with chronic hepatitis C treated with interferon-alpha. In 28 of these patients, results of the assay were compared with genotypes and quantitative levels of HCV-RNA in serum before therapy. HCV-RNA was detected by a reverse transcription polymerase chain reaction using the 5'-noncoding region as a primer. Genotypes were determined by using type-specific primers, and serum levels of HCV-RNA were determined by a competitive reverse transcription polymerase chain reaction (RT-PCR). HCV-RNA disappeared from serum in eight of 10 responders (80%), but in only one of the 26 nonresponders (3.8%) at the second week of therapy (P < 0.0005). The time until the disappearance of HCV-RNA was correlated with the serum level of HCV-RNA present before therapy (P < 0.05). The early disappearance of HCV-RNA from serum during interferon therapy was useful in predicting a sustained response in patients with chronic hepatitis C.