Fetal microchimerism in primary biliary cirrhosis

BACKGROUND/AIMS: Recent studies have suggested a role of fetal microchimerism in the pathogenesis of scleroderma. The present study investigated the potential role of fetal microchimerism in primary biliary cirrhosis (PBC), a closely related disease. METHODS: A quantitative nested polymerase chain reaction was used to detect Y-chromosome sequences in the peripheral blood or the liver of PBC women and controls having male children and no transfusion or miscarriage history. RESULTS: Male microchimerism was found in the peripheral blood from 45% (9 of 20) of PBC women and 25% (5 of 20) of healthy controls matched for the number of male children and age of the youngest son (p=0.28), and in the liver-biopsy specimens from 33% (5 of 15) of PBC women and 32% (8 of 25) of controls. The level of chimerism did not differ between patients and controls either in blood or in liver. Microchimerism was not related to the severity of the disease but was more frequent in PBC patients with anticentromere antibodies (p=0.049). CONCLUSIONS: Fetal microchimerism does not seem to play a major role in most cases of PBC. However, the association with anticentromere antibodies suggests a possible role in the subgroup of patients with CREST syndrome or scleroderma.     

Interleukin-6 production by peripheral blood monocytes in patients with chronic liver disease and acute viral hepatitis.

The in vitro production of the acute-phase mediator interleukin-6 by peripheral blood monocytes derived from patients with various liver diseases was studied. Compared with healthy controls (n = 45; 860 +/- 92 U/ml, mean +/- SEM), monocytes from patients with chronic hepatitis B produced significantly lower amounts of interleukin-6 (n = 14; 424 +/- 126 U/ml) after stimulation with lipopolysaccharide (p = 0.02), whereas monocytes from patients with chronic hepatitis non-A, non-B secreted normal amounts of interleukin-6 (n = 13; 672 +/- 151 U/ml; n.s.). In contrast, monocytes of patients suffering from alcoholic liver cirrhosis (n = 22; 1310 +/- 153 U/ml) or primary biliary cirrhosis (n = 6; 1450 +/- 186 U/ml) produced higher amounts of interleukin-6 than healthy control individuals (p = 0.03, respectively). Lipopolysaccharide-stimulated monocytes derived from patients with acute hepatitis A, B and non-A, non-B showed an interleukin-6 production not different from that seen in healthy control individuals and did not experience a discernible change during the course of the acute disease. These results suggest that the production of the acute-phase mediator interleukin-6 varies in chronic liver disease in accordance with various etiologies with a reduced lipopolysaccharide-inducible interleukin-6 response in chronic hepatitis B and an enhanced response in alcoholic liver cirrhosis and primary biliary cirrhosis.     

Value of serum immunoglobulins in the diagnosis of liver disease

Serum immunoglobulins were determined in 145 consecutive patients with biopsy-proven steatosis, alcoholic hepatitis, alcoholic hepatitis with fibrosis, alcoholic hepatitis with cirrhosis, inactive cirrhosis, chronic active alcoholic hepatitis, chronic active hepatitis, primary biliary cirrhosis and nonspecific hepatitis. IgM was both a sensitive (90.5%) and specific (86.2%) marker for primary biliary cirrhosis, and mean IgM levels were higher in primary biliary cirrhosis than in other diagnostic categories (p less than 0.05). IgA levels were most commonly elevated in alcoholic liver disease (p less than 0.005). IgA detected 95% of alcoholic disease, but was poorly specific (41.1%). A trend of rising IgA with increasing severity of alcoholic injury was observed, but the differences were not significant. IgG was most commonly elevated in chronic active hepatitis and alcoholic hepatitis with cirrhosis, but the IgG values did not differ significantly from those found in other diagnostic categories. Our results substantiate assertions of a diagnostic sensitivity for elevated IgA in alcoholic liver disease and IgM in primary biliary cirrhosis. With the exception of IgM in primary biliary cirrhosis, however, serum immunoglobulins are not specific markers of liver histology.     

Lack of evidence for involvement of fetal microchimerism in pathogenesis of primary biliary cirrhosis

Microchimerism may be involved in the etiopathogenesis of autoimmune diseases such as scleroderma. Primary biliary cirrhosis (PBC) shares some features with scleroderma, including a female predominance and a histologic picture reminiscent of chronic graft-versus-host disease. Our aim was to detect Y-chromosome-specific sequences as a marker for microchimerism in liver tissue of female patients with PBC. Liver biopsies of 105 female patients were investigated (28 patients with primary biliary cirrhosis, 25 patients with chronic hepatitis C, 6 patients with chronic hepatitis B, 9 with autoimmune hepatitis, and 37 patients with other liver diseases) by a sensitive Y-chromosome-specific polymerase chain reaction and/or fluorescence in situ hybridization (FISH) technique for the detection of the Y chromosome on a single cell level. In the liver of 9 (8.6%) female patients Y-chromosome-specific sequences were detected by PCR. Five of the patients had PBC as underlying disease, 2 had chronic hepatitis C, and 2 other liver diseases. No significant difference in the positivity rate for Y-specific sequences in females with PBC and patients with other liver diseases was found (P > 0.05). By FISH, single cells with one Y chromosome were detected in liver specimens from 3 of 21 patients suffering from PBC and from 1 of 13 patients with other liver diseases. In summary, microchimerism can be detected in livers of patients with hepatic diseases. However, in our study we found no evidence for an increased prevalence of microchimerism in the livers of patients with primary biliary cirrhosis. Our data suggest that microchimerism does not play a significant role in the development of PBC.     

The immune response to alkaline phosphatase and other immunogens in patients with primary biliary cirrhosis

BACKGROUND/AIMS: Primary biliary cirrhosis is a potentially lethal hepatobiliary disorder in which 90% of the patients are women. Histologically, the disease is characterized by a progressive destruction of intrahepatic bile ducts by autoreactive T lymphocytes. Although the underlying etiology remains unknown, potential hypotheses must take into account; a) the predilection of the disease for women of childbearing age, b) the frequent coexistence of bone and intestinal involvement, and c) the high prevalence of autoantibodies directed towards intracellular enzymes. With these considerations in mind, we hypothesized that exposure to P-ALP (placental alkaline phosphatase) during pregnancy results in autoreactivity directed towards all human tissues harboring the ALP enzyme (liver, bone and intestine) in genetically predisposed individuals. METHODOLOGY: To test this hypothesis, we stimulated peripheral blood mononuclear cells of primary biliary cirrhosis patients (n = 17) cholestatic liver disease controls (n = 6) and healthy controls (n = 14) with P-ALP, polyclonal activators (phytohemagglutinin [PHA], anti-CD3) and recall antigens (tetanus toxoid, streptokinase). We then determined their proliferative and cytokine responses by 3H-thymidine incorporation and ELISA assays for Il-10, IL-6, tumor necrosis factor-alpha and interferon-gamma, respectively. RESULTS: The results of the study revealed that the proliferative response to P-ALP was similar in peripheral blood mononuclear cells from primary biliary cirrhosis patients, cholestatic and healthy controls. Although the proliferative responses to PHA (P < 0.001) and anti-CD3 (P < 0.001) were decreased in peripheral blood mononuclear cells from primary biliary cirrhosis patients when compared to both control groups, responses to the recall antigens; tetanus toxoid and streptokinase were similar in the three groups. Cytokine production following exposure to P-ALP, polyclonal activators or recall antigens in peripheral blood mononuclear cells from primary biliary cirrhosis patients was similar to that of cholestatic and healthy controls. CONCLUSIONS: The results of the above experiments suggest that P-ALP is unlikely to be the target autoantigen in primary biliary cirrhosis. The results also support the findings of other investigators that primary biliary cirrhosis patients have suppressed proliferative responses to polyclonal stimulation.     

Soluble interleukin 2 receptor in acute viral hepatitis and chronic liver disease

Serum levels of soluble interleukin 2 receptor were determined in patients with acute viral hepatitis and patients with various chronic liver diseases. In addition, the ability of peripheral blood mononuclear cells of patients with alcoholic cirrhosis to generate soluble interleukin 2 receptor following mitogenic stimulation was studied in vitro. Serum soluble interleukin 2 receptor concentrations in all patients with acute viral hepatitis were found to be significantly elevated (1,319 +/- 527 units per ml) during the first week after onset of disease, as compared to healthy control individuals (375 +/- 102 units per ml; p less than 0.0005) and declined toward normal levels during the course of the illness. Similarly, patients suffering from chronic liver disease such as alcoholic liver cirrhosis (1,172 +/- 507 units per ml), primary biliary cirrhosis (619 +/- 190 units per ml) or chronic active HBsAg+ hepatitis (941 +/- 357 units per ml) showed increased serum soluble interleukin 2 receptor concentrations (p less than 0.0005 vs. controls, respectively). In vitro mitogen stimulation of peripheral mononuclear cells derived from patients with alcoholic cirrhosis resulted in a soluble interleukin 2 receptor production not different from that seen in healthy individuals, suggesting that elevated soluble interleukin 2 receptor serum levels seen in this disease are not the result of an increased synthesis by circulating lymphocytes. Due to the ability of soluble interleukin 2 receptor to bind free interleukin 2--thus making it a potential immunoregulatory molecule--its high serum levels could explain some of the immunologic abnormalities observed in acute and chronic liver disease.     

Mononuclear cell complement receptor blockade in primary biliary cirrhosis.

Peripheral blood monocyte and lymphocyte receptors for Fc and C3b fragments were examined in vitro in patients with primary biliary cirrhosis and other chronic liver diseases using sheep red blood cells coated with anti-SRBC IgG1 (to detect Fc receptors) and with anti-SRBC IgM and complement (to detect C3b receptors). The number of C3b receptors detected on 100 monocytes was significantly lower in patients with primary biliary cirrhosis (23.0 +/- 12.0, mean +/- 1 SD) compared with normal controls (57.4 +/- 16.9) and other chronic liver disease (HBsAg negative chronic active hepatitis 62.0 +/- 17.0, alcoholic cirrhosis 50.9 +/- 4.0), while the number of Fc receptors detected on 100 monocytes was not significantly different in all the groups (primary biliary cirrhosis 72.8 +/- 28.6, chronic active hepatitis 74.7 +/- 14.0, alcoholic cirrhosis 58.0 +/- 13.5 and normal controls 69.6 +/- 19.9). When mononuclear cells isolated from normal individuals were pre-incubated with serum from patients with primary biliary cirrhosis before testing their receptor function there was a significant reduction in the number of C3b receptors detected per 100 monocytes (27.6 +/- 10.8) compared with pre-incubation with normal serum (72.0 +/- 18.0). This reduction in C3b-receptor function was again observed when the serum used for pre-incubation was depleted of circulating immune complexes; but when complement was further depleted from these sera, the number of C3b-receptors detected after pre-incubation was similar to normal values (64.0 +/- 11.8). Lymphocyte receptors showed a similar pattern of results. This implies a specific C3b receptor blockade on monocytes and lymphocytes from patients with primary biliary cirrhosis which appears to be because of blocking by serum factor(s) including complement fragments.     

Male microchimerism in women without sons: quantitative assessment and correlation with pregnancy history

PURPOSE: Fetal microchimerism, derived from fetal cells that persist after pregnancy, is usually evaluated by tests for male microchimerism in women who gave birth to sons. We investigated male microchimerism in women without sons and examined correlation with prior pregnancy history. Immunologic consequences of microchimerism are unknown. We studied healthy women and women with rheumatoid arthritis (RA). METHODS: Y-chromosome-specific real-time quantitative polymerase chain reaction was used to test peripheral blood mononuclear cells of 120 women (49 healthy and 71 with RA). Results were expressed as the number of male cells that would be equivalent to the total amount of male DNA detected within a sample containing the equivalent of 100000 female cells. RESULTS: Male microchimerism was found in 21% of women overall. Healthy women and women with RA did not significantly differ (24% vs 18%). Results ranged from the DNA equivalent of 0 to 20.7 male cells per 100000 female cells. Women were categorized into 4 groups according to pregnancy history. Group A had only daughters (n = 26), Group B had spontaneous abortions (n = 23), Group C had induced abortions (n = 23), and Group D were nulligravid (n = 48). Male microchimerism prevalence was significantly greater in Group C than other groups (8%, 22%, 57%, 10%, respectively). Levels were also significantly higher in the induced abortion group. CONCLUSIONS: Male microchimerism was not infrequent in women without sons. Besides known pregnancies, other possible sources of male microchimerism include unrecognized spontaneous abortion, vanished male twin, an older brother transferred by the maternal circulation, or sexual intercourse. Male microchimerism was significantly more frequent and levels were higher in women with induced abortion than in women with other pregnancy histories. Further studies are needed to determine specific origins of male microchimerism in women.     

Immunophenotyping of lymphocytes in liver tissue of patients with chronic liver diseases by flow cytometry.

Immunological factors are important in the pathogenesis of a spectrum of hepatobiliary diseases. To characterize the nature of specific immunological responses in liver disease, we determined lymphocyte changes in liver tissue and in blood using flow cytometry. A total of 113 liver biopsy specimens was collected from patients with the following diseases: 19 chronic hepatitis B; 39 chronic non-A, non-B hepatitis; 27 alcoholic liver disease; 10 hepatic malignancy; 8 autoimmune hepatitis; 6 fatty liver and 4 primary biliary cirrhosis. The lymphocytes were isolated from the liver biopsy specimens by mechanical and enzymatic methods. The lymphocyte yield was 7,901 +/- 575 cells/mg of liver tissue. The viability of lymphocytes was 97.7% +/- 0.3%. Lymphocytes were stained with four pairs of two-color mixed fluorescein-conjugated monoclonal antibodies, including T4-T8 (CD4/CD8), T11-B1 (CD2-CD20), NKH1-T8 (CD56-CD8), IL-2R1-T11 (CD25-CD2), and the ratios were determined by an Epics Profile flow cytometer. Immunophenotyping of lymphocytes in whole blood samples was simultaneously analyzed. Variability in lymphocyte yield and different patterns of lymphocyte subsets were found in the liver biopsy specimens. The yields of lymphocytes from patients with chronic non-A, non-B and autoimmune hepatitis were highest, and the lowest yield was from patients with fatty liver. Patients with primary biliary cirrhosis, fatty liver and hepatic malignancy had relatively high ratios of CD4/CD8, CD56/CD8 and CD25/CD2; whereas patients with chronic hepatitis B, autoimmune hepatitis and non-A, non-B hepatitis had lower ratios of CD4/CD8, CD56/CD8 and CD25/CD2. No difference in lymphocyte ratios between the patients with cirrhotic and noncirrhotic alcoholic liver disease was found.(ABSTRACT TRUNCATED AT 250 WORDS)     

A comparison of fibrosis progression in chronic liver diseases

BACKGROUND/AIMS: No study has compared the liver fibrosis progression rates among chronic liver diseases and the risk factors in order to better organize screening strategies. METHODS: A total of 4852 patients were retrospectively studied (chronic hepatitis C (HCV) [n=2313], human immunodeficiency virus (HIV)-HCV co-infection (HIV-HCV [n=180]), hepatitis B (HBV [n=777]), alcoholic liver disease (ALD [n=701]), primary biliary cirrhosis (PBC [n=406]), genetic hemochromatosis (GH [n=383]) auto-immune hepatitis (AIH [n=57]) and delta hepatitis (n=35). The fibrosis progression rates were estimated from birth and from the date of exposure, when known, to the first biopsy. RESULTS: There were highly significant differences in the rates of fibrosis progression, the most rapid being HIV-HCV co-infection (50% cirrhosis percentile at 52 years of age) and the slowest being PBC (50% cirrhosis percentile at 81 years). There was an acceleration of fibrosis progression with aging. Fibrosis progression was slower in females compared with males for HCV, HBV, GH, and PBC. In contrast, in ALD, the fibrosis progression was more rapid in females. CONCLUSIONS: Rates of fibrosis progression differ markedly between the predominant causes of chronic liver disease, and according to age and gender. Patients with HIV-HCV co-infection are at particularly high risk of fibrosis progression.     

The clinical significance of slightly to moderately increased liver transaminase values in asymptomatic patients

BACKGROUND: Our aim was to study liver disorders in asymptomatic patients with slightly to moderately increased liver transaminase values in a population living in an area with a low prevalence of viral and hereditary liver diseases. METHODS: One hundred and fifty consecutive patients with slightly to moderately increased liver transaminases for at least 6 months without symptoms or signs of liver disease were included. Median (range) was 0.75 microkat/l (0.24-2.9) for aspartate aminotransferase (ASAT) and 1.18 microkat/l (0.28-4.5) for alanine aminotransferase (ALAT). A percutaneous liver biopsy was performed, and blood was sampled for a detailed biochemical and serologic profile. RESULTS: Chronic viral hepatitis C was found in 15.3% of the patients, autoimmune hepatitis in 1.3%, primary biliary cirrhosis in 1.3%, and heterozygotic alpha-1-antitrypsin deficiency in 0.7%. Presumed alcoholic liver disease was diagnosed in 8%, and non-alcoholic steatohepatitis in 2%. Chronic hepatitis with no obvious etiology was diagnosed in 24%, of whom 39% had interface hepatitis (piecemeal activity). Seventy-one per cent of these 39% had measurable levels of autoantibodies, but IgG levels within normal limits prevented the 'clinical' diagnosis of autoimmune hepatitis. Liver steatosis was the diagnosis in 40%. Most were overweight and had increased serum triglyceride levels. However, in 13.3% the fatty infiltration was considered 'essential', as both body mass index (BMI) and triglyceride levels were normal. Other diagnoses were liver fibrosis with no obvious inflammatory activity (3.3%), cirrhosis of unknown etiology (0.7%), and for the remaining (3.3%) patients histopathologic findings were considered 'normal'. Cirrhosis was found in five biopsy specimens: hepatitis C (n = 2), autoimmune hepatitis (n = 1), primary biliary cirrhosis (n = 1), and cryptogenic cirrhosis (n = 1). No concomitant disease was of importance for the diagnosis and/or histopathologic findings. No obvious drug-related increased liver test results were found with any single drug. However, patients with chronic hepatitis of unknown etiology, especially with interface hepatitis, significantly more often than the rest of the population were receiving drug treatment. CONCLUSION: Most transaminitis patients had steatosis, and some had defined diseases including chronic hepatitis C. Chronic hepatitis of unknown etiology was found in a substantial proportion (24%) of a population living in an area with a low burden of hepatic viruses and genetic disorders.     

Adenosine Deaminase Isoenzymes in Liver Disease

To clarify the clinical significance of increased serum adenosine deaminase (ADA) activity, and its mechanisms in various liver diseases, ADA isoenzyme activities (ADAI and ADA2) in serum and in peripheral blood mononuclear cells were studied. High serum ADA activities were found in patients with acute hepatitis, alcoholic hepatic fibrosis, chronic active hepatitis, liver cirrhosis, and hepatoma. The ADA2:ADA ratio was decreased in acute hepatitis, but was increased in chronic active hepatitis and liver cirrhosis. Clinically, ADA2 activity was correlated with serum γ-globulin levels. In chronic active hepatitis, total ADA activities in the peripheral blood mononuclear cells were similar to those in controls. Furthermore, ADA2 activities after phytohemagglutinin (PHA) stimulation were significantly lower than those without PHA stimulation, although total ADA activities were increased after PHA stimulation. These findings suggest that serum ADA isoenzyme activities may be a new marker for liver disease, and that the increased serum ADA2 in chronic active hepatitis is unlikely to be the result of an increase in ADA2 production by activated peripheral blood mononuclear cells.     

Male cell microchimerism in normal and diseased female livers from fetal life to adulthood

Male microchimerism is frequent in the adult female liver and is attributed to fetal cells originating from previous male offspring. It has never been studied in pregnant women, female children, or fetuses. We examined its frequency and cellular nature in normal and diseased female livers from fetal life to adulthood. Forty-six liver samples from 29 women, 6 female children, and 11 female fetuses were screened for the Y chromosome via polymerase chain reaction (PCR) assay and fluorescent in situ hybridization (FISH). The X chromosome was used as an internal control. A third PCR assay was used for Y genotyping. The Y chromosome was detected in 5 of 6 children, 7 of 11 fetuses, 3 of 9 women with normal liver, 7 of 10 women with chronic hepatitis C, 5 of 6 women with acute liver disease during pregnancy with male offspring, and 2 of 4 nonpregnant women with fulminant hepatitis. In positive samples, the mean XY/XX ratio was 0.012 (+/-0.004). In women, male microchimerism was correlated with previous male offspring. Male hepatocytes, detected via FISH combined with anti-hepatocyte immunohistochemistry, were observed only in fetuses (4/9) and in postpartem women (4/6). Y genotypes were different from each other in 4 of 5 female livers. In conclusion, male liver microchimerism is frequent in normal and diseased female livers. The presence of male cells in the liver of female children and fetuses is probably due to the transplacental transmission of fetal cells preexisting in the mother and acquired either from previous pregnancy with male offspring or during the mother's own fetal life.     

Deficiency of antibody formation to HBsAg in the pathogenesis of chronic hepatitis and cirrhosis?

Sera of 832 healthy persons and patients suffering from chronic inflammatory liver disease were investigated by radioimmunoassay for HBsAg and anti-HBs. Diagnosis in patients was secured by biopsy. The persons were divided into: 1. Healthy persons: n = 478 blood donors, hospital especially exposed to HBV, patients with healed hepatitis; 2. Patients: n = 354 acute hepatitis, chronic persistent and aggressive hepatitis, post-hepatitic, cryptogenic and alcoholic cirrhosis. The results demonstrate considerable accumulation of HBsAg in chronic liver disease (72% in CAH, 66% in posthepatic liver cirrhosis) whereas anti-HBs was more frequently observed in healthy persons (38% in hospital staff, 49% in healed hepatitis). Furthermore, HBsAg and anti-HBs were frequently observed simultaneously in chronic hepatitis and cirrhosis (23% in CAH). A strong shift in the relation of antigen to antibody to the disadvantage of antibody in the examined collectives of chronic hepatitis and cirrhosis is evident. Chronic inflammatory HBsAg positive liver disease should therefore be regarded as chronic virus infection. We suppose an absolute or relative deficiency of antibody to HBsAg is probably an important factor for the development of chronicity of hepatitis B.     

Incidence of parenchymal liver diseases in Denmark, 1981 to 1985: analysis of hospitalization registry data. The Danish Association for the Study of the Liver

The sex-specific and age-specific incidence rates of the major parenchymal liver diseases in a North European population were estimated using a computerized registry of all admissions to somatic hospitals in Denmark. The incidence was calculated by counting all incident cases of these diseases reported to the registry in the 5-yr period 1981 to 1985 and dividing the number of cases by the number of person-years at risk in this period. The incidence rates (per million person-years) were for men and women, respectively: infectious hepatitis, 109 and 71; toxic hepatitis, 19 and 22; chronic hepatitis, 27 and 29; alcoholic cirrhosis, 190 and 85; nonalcoholic nonbiliary cirrhosis, 110 and 82; primary biliary cirrhosis, 4 and 14. The pattern of the age-specific incidence rates was similar in men and women in infectious hepatitis, alcoholic cirrhosis, nonalcoholic nonbiliary cirrhosis and primary biliary cirrhosis. Toxic and chronic hepatitis had a higher incidence in women than in men only in older age groups. The incidence of idiopathic hemochromatosis, Wilson's disease, secondary biliary cirrhosis, portal vein thrombosis and Budd-Chiari's syndrome were less than four in both sexes.     

Relationship between apoptasis, tumour necrosis factor, cell proliferation in chronic cholestasis

BACKGROUND: Target of the immune response in chronic autoimmune cholestasis, is the bile duct epithelium. Lymphocytic infiltration and apoptosis have both been suggested to mediate the destruction of hepatocytes and biliary epithelium in primary biliary cirrhosis. AIMS: To further address this issue in two cholestatic liver diseases characterized by an autoimmune pathogenesis and, furthermore, evaluate the relationship between apoptosis and both tumour necrosis factor alpha and cell proliferation. METHODS: Liver tissue specimens from 16 patients with primary biliary cirrhosis, 15 with primary sclerosing cholangitis, and 16 with chronic hepatitis C (controls) were evaluated. DNA-fragmentation of apoptotic cells was ascertained by the TdT-mediated deoxyuridine triphosphate nick-end labelling method. Tumour necrosis factor alpha expression and cell proliferation (Ki-67 antigen) were assayed by immunohistochemistry. RESULTS: Hepatocytes with DNA fragmentation were observed in 75% of patients with primary biliary cirrhosis, in 66.6% with primary sclerosing cholangitis, and in 43.7% with chronic hepatitis C. Biliocytes showed apoptosis in only 3 cases of primary biliary cirrhosis. Biliocytes showed a strong cytoplasmic expression in 4 cases (1 primary biliary cirrhosis, 2 primary sclerosing cholangitis and 1 chronic hepatitis C). A few intralobular and portal inflammatory mononuclear cells expressing tumour necrosis factor alpha were observed in 62.5% of patients with primary biliary cirrhosis, 46.1% with primary sclerosing cholangitis, and 56.2% with hepatitis C virus chronic hepatitis. The amount of intraportal mononuclear cells expressing Ki-67 antigen was significantly higher in primary biliary cirrhosis specimens than in primary sclerosing cholangitis (p<0.001) or hepatitis C virus-related chronic hepatitis (p<0.03). No correlation was found within the 3 groups of patients between the Ki-67 histological score and the severity of liver disease. Moreover, no relationship was found between TdT-mediated deoxyuridine triphosphate nick-end labelling and either tumour necrosis factor alpha or Ki-67 staining. CONCLUSIONS: Apoptosis is a phenomenon which frequently involves hepatocytes in chronic autoimmune cholestasis. This process is apparently parallel, but unrelated to cell proliferation. Cell proliferation mainly involves mononuclear cells in portal tracts of primary biliary cirrhosis specimens. The finding of tumour necrosis factor alpha expression in biliocytes deserves further study to establish whether this cytokine is involved in triggering bile duct lesions.     

Studies on the effects of estrogen on in vitro antibody production in autoimmune liver diseases, including lupoid hepatitis and primary biliary cirrhosis

Antibody-forming cells produced by adding trinitrophenylated sheep red blood cells (TNP-SRBC) were induced, when peripheral blood mononuclear cells from normal individuals and patients with autoimmune liver diseases, including lupoid hepatitis and primary biliary cirrhosis, were stimulated in vitro with pokeweed mitogen (PWM). Although antibody responses were significantly augmented by adding estrogen simultaneously with PWM to mononuclear cell cultures prepared from normal individuals and autoimmune liver diseases patients, a significant difference was observed according to the concentrations of estrogen between the normal subjects and patients. These observations suggest that a different responsiveness to the different concentrations of estrogen underlines the immunological abnormalities involved in autoimmune liver diseases, including lupoid hepatitis and primary biliary cirrhosis.     

Antibodies against mitochondrial dehydrogenase complexes in primary biliary cirrhosis

Antimitochondrial antibodies, serological hallmarks of primary biliary cirrhosis, recently were found to be directed against the E2 subunits of mitochondrial dehydrogenase complexes (pyruvate, branched-chain ketoacid, and alpha-ketoglutarate dehydrogenases). The objectives of this study were to extend these findings and to determine whether purified immunoglobulin from the sera of patients with primary biliary cirrhosis inhibit activity of these dehydrogenase complexes in vitro. Sera were examined from 14 patients with primary biliary cirrhosis (13 mitochondrial antibody positive), 23 with rheumatic diseases and 30 with chronic active hepatitis (all 53 positive for mitochondrial antibodies by indirect immunofluorescence), 10 with alcoholic liver disease, and 5 normal controls. Antibodies against pyruvate dehydrogenase, branched-chain alpha-ketoacid dehydrogenase and alpha-ketoglutarate dehydrogenase complexes were detected by immunoblot and quantified by enzyme-linked immunosorbent assay. Of the 14 serum samples obtained from patients with primary biliary cirrhosis, 13, 11, and 2 samples tested positive by immunoblot for the E2 subunits of pyruvate, branched-chain ketoacid, and alpha-ketoglutarate dehydrogenase, respectively. In contrast, samples from subjects with rheumatic diseases, chronic active hepatitis, and alcoholic liver disease and control subjects tested negative for these antibodies. Serum immunoglobulin G with high titers of mitochondrial antibodies showed concentration-dependent inhibition of activity of the dehydrogenase complexes, and close correlation (r = 0.917, n = 13) was observed between inhibitory activity against pyruvate dehydrogenase complex and the reciprocal titer of immunoglobulin against this complex. These data suggest that such autoantibodies, besides serving as diagnostic markers for primary biliary cirrhosis, may have a pathogenic role by their ability to inhibit important mitochondrial enzymes.