Immunohistochemical characterization of hepatic tissue lymphocyte subpopulations in liver disease

Detection of a soluble form of the human adhesion receptor lymphocyte function-associated antigen-3 (LFA-3) in patients with chronic liver disease

BACKGROUND/AIMS

Multiple immune functions, such as cytotoxic reactions, B cell differentiation, and monocyte activation, are mediated via the adhesion receptor/ligand pairs CD2/lymphocyte function-associated antigen(LFA)-3 and LFA-1/ intercellular adhesion molecule(ICAM)-1. Since soluble forms of LFA-3 (sLFA-3) and ICAM-1 (sICAM-1) can interfere with these functions, we asked whether increased levels of sLFA-3 can be found in patients with different forms of chronic liver disease and/or hepatocellular carcinoma.

METHODS

sLFA-3 was measured in sera from 84 patients with chronic liver disease (39 with chronic viral liver disease, 30 with autoimmune liver disease, 12 with alcoholic cirrhosis, 3 with other causes of cirrhosis), 24 patients with hepatocellular carcinoma (15 with and 9 without cirrhosis), and 61 normal controls. From 36 of the patients with liver cirrhosis, arterial and hepatic venous serum samples were simultaneously obtained and tested for sLFA-3 and sICAM-1.

RESULTS

In comparison to controls, sLFA-3 levels were elevated in patients with liver cirrhosis due to autoimmune liver disease (p < 0.0001) and viral liver disease (p = 0.001), but not in patients with alcoholic cirrhosis. Increased sLFA-3 levels were also found in patients with hepatocellular carcinoma and liver cirrhosis. However, sLFA-3 was not significantly elevated in sera from patients with autoimmune liver disease, viral liver disease, and hepatocellular carcinoma without concomitant liver cirrhosis. No difference was found between arterial and hepatic venous serum levels of sLFA-3 and sICAM-1. sLFA-3 levels correlated positively with aspartate transaminase, alkaline phosphatase, bilirubin, sICAM-1, and inversely with albumin and cholinesterase.

CONCLUSIONS

Taken together, sLFA-3 serum concentrations of patients with liver cirrhosis due to autoimmune liver disease or viral liver disease and of patients with hepatocellular carcinoma and cirrhosis are significantly increased compared to controls. Elevated sLFA-3 and sICAM-1 levels might reflect the generalized inflammation in cirrhosis and by interference with cell-cell interactions sICAM-1 and sLFA-3 may limit the extent of inflammation.

Immunopathogenesis of viral hepatitis

More than 500 million people world-wide suffer from viral hepatitis which can be caused by a variety of distinct infectious agents. The spectrum of disease, which ranges from acute self-limited hepatitis to liver cirrhosis, not only reflects the different biological properties and pathogenicity of the hepatitis viruses, but is also the result of the specific interaction between each virus and the immune system of the infected host. The immune response plays a crucial role in the elimination of the infecting virus as well as in disease pathogenesis and is described in detail for acute and chronic hepatitis B and C virus infection. Acute hepatitis B virus infection is characterized by a vigorous, polyclonal cytotoxic T lymphocyte response against HBV that is not readily detectable in patients with chronic hepatitis B, suggesting that resolution of disease is mediated by the HBV-specific CTL response in these patients. Because traces of virus as well as HBV-specific CTL can persist for decades after clinical recovery, continuous priming of new CTL by minute traces of virus is thought to protect from reactivation of disease. In contrast, the hepatitis C virus causes chronic liver disease despite a polyclonal and multispecific immune response, suggesting that distinct immunological and viral mechanisms determine the different clinical outcome of HBV and HCV infection. Their implications for the development of immunomodulatory vaccines to cure patients with chronic viral hepatitis are discussed.

Bronchoalveolar lavage in alcoholic liver cirrhosis. T-lymphocyte subsets and immunoglobulin concentrations

The purpose of this study was to determine the phenotype profiles of immune effector cells and the concentrations of immunoglobulins in the lower respiratory tract of non-smoking patients with alcoholic liver cirrhosis (ALC). Nine nonsmoking patients with liver biopsy-proved ALC (grade B or C cirrhosis in Child's classification), free of clinical pulmonary symptoms, and with normal chest roentgenogram were included in the study. The control group included 12 healthy nonsmokers. Each patient had fiberoptic bronchoscopy with bronchoalveolar lavage (BAL). The number of T cells and of lymphocyte subpopulations was determined by immunofluorescence studies using monoclonal antibodies that were specific for CD3, CD4, and CD8 markers. Patients with ALC exhibited a dramatically increased percentage of CD8+ cells in BAL that induced a low CD4/CD8 ratio (0.96 +/- 0.15 vs 1.8 +/- 0.12 in healthy controls). Further characterization of lymphocyte subsets' dual immunofluorescence analysis demonstrated that most of the CD8+ alveolar lymphocytes had a phenotype of cytotoxic cells (CD8+ CD11b-; 48 percent +/- 13 in ALC vs 10 percent +/- 5 in controls). ALC was associated with an appreciable alveolar-capillary "leak" as demonstrated by a significant increase in BAL fluid albumin. In addition, the concentrations of immunoglobulins in BAL fluid were significantly greater in ALC than in controls. However, the relative (to albumin) coefficient of excretion of IgG, A, and M in and alpha 2-macroglobulin BAL fluid was not significantly different between controls and ALC. Our results indicate that increased proportions of CB8+ and especially of CD8+ CD11b- cells are a common feature in the lower respiratory tract of nonsmoking patients with ALC. These changes may be of potential functional importance in the regulation of the local pulmonary immune response in ALC.

HCV infection, hepatic HLA display and composition of the mononuclear cell inflammatory infiltrate in chronic alcoholic liver disease

Viral infection may play a role in alcoholic liver disease with histological features of chronic active hepatitis (CAH). Human leucocyte antigen (HLA) hepatocellular display is supposed to allow HLA-restricted T-lymphocyte cytotoxicity in chronic viral hepatitis. We studied the presence of serum anti-hepatitis C virus (HCV) antibodies, the hepatic HLA display and the composition of the mononuclear cell infiltrate in 16 patients with alcoholic liver disease and histological features of CAH and in 11 patients with alcohol-related degenerative changes. All patients were negative for hepatitis B virus (HBV) markers. Anti-HCV were tested by microplate ELISA. Class I HLA A, B, class II HLA DR, lymphocytes pan T, T helper/inducer, T suppressor/cytotoxic, B, and K NK cells were stained on liver cryostat sections by monoclonal antibodies and double indirect immunoperoxidase. Anti-HCV were present in all the patients with features of CAH and absent in those with only degenerative changes. In livers with features of CAH the mononuclear cell infiltrate consisted largely of T lymphocytes with marked prevalence of suppressor/cytotoxic cells in periportal and lobular areas. K NK cells were rare. Class I HLA, diffusely displayed on bile duct epithelium and on sinusoidal cells, also appeared on liver cells in the areas of periportal and lobular necrosis, namely on the hepatocytes in close contact with suppressor/cytotoxic T cells. In livers with only degenerative changes class I HLA were diffusely displayed on bile duct epithelium and on sinusoidal cells but absent on the hepatocytes. In all the specimens HLA DR antigens were expressed on sinusoidal and inflammatory cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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)

Studies on the composition of the mononuclear cell infiltrates in liver from patients with chronic active delta hepatitis

To evaluate the immune process involved in the pathogenesis of liver cell damage in chronic hepatitis delta virus infection, a panel of monoclonal antibodies against pan T cells (Leu 4), inducer/helper T cells (Leu 3a+3b), suppressor/cytotoxic T cells (Leu 2a), B cells (Leu 12), monocytes/macrophages (Leu M3) and NK/K cells Leu 7) was used to characterize the subsets of the mononuclear cell infiltrates in livers from 12 patients with chronic type D hepatitis, with special emphasis on the areas of periportal piecemeal necrosis and intralobular necrosis. A control group of 12 patients with chronic type B hepatitis was also studied for comparison. The results revealed that the livers from patients with chronic type D hepatitis showed a prominent mononuclear cell infiltration in portal/periportal and intralobular areas. Furthermore, the vast majority of the mononuclear cell infiltrates in liver were T cells, which constituted more than 80% of the cells in the areas of periportal piecemeal necrosis and intralobular necrosis and about 60% of the cells in the portal tract, whereas B cells, monocytes/macrophages and NK/K cells were relatively uncommon. Among T cell populations, the inducer/helper T cells were predominant in the portal were predominant in the areas of piecemeal necrosis and intralobular necrosis. The distribution of the mononuclear cell subsets in relation to the different topographical areas of the liver in patients with chronic type B hepatitis was essentially the same as that observed in chronic type D hepatitis. Our findings therefore suggest that T cell-mediated immunity might play a role in the pathogenesis of chronic type D hepatitis, similar to that suggested for chronic type B hepatitis.

Antibody dependent cytotoxicity in chronic active liver disease

Twenty-six patients with chronic active liver disease (CALD) and a control group (8 patients with atrophic gastritis and 10 healthy people) underwent a microcytotoxicity (MCT) test using a primary line of human hepatocytes (5 1/2 month old human embryo) in the presence of rabbit complement. In 57.6% of the cases with CALD the test was positive (over 60% of hepatocytes lysed on contact with the patients' serum). The controls showed a negative MCT test, except for one case (12.5%) of atrophic gastritis. The positive results of the test in the CALD patients coincided with the evolutive stage of the disease and with obvious immune, humoral and cellularly, disturbances. The mechanism of the antibody dependent cytotoxicity mechanism in the hepatocytolysis in CALD is being demonstrated; the MCT test may be a marker of the evolution of the disease.

Immunoelectron microscopic observations on the inflammatory infiltrates and HLA antigens in hepatitis B and non-A, non-B

The present knowledge of the inflammatory reaction occurring in situ during hepatitis B favors a T cell-dependent MHC-restricted immune response. However, the reports in the literature are primarily based on the application of monoclonal antibodies directed at different lymphocyte subsets which discern only lymphocytic phenotypes and do not reflect the actual situation adequately. Therefore, we investigated the liver biopsies of patients with hepatitis B (28 patients) and non-A, non-B (21 patients) by immunoelectron microscopy with monoclonal antibodies directed at lymphocyte subtypes (pan-B, pan-T, T8, T4 and NKH1) and at activation epitopes (IL-2 receptor, TA1 and T11/3) as well, in order to determine the phenotype in association with the activation status of the lymphocytes that are in close contact with hepatocytes; thus, establishing an effector-target cell relationship on the ultrastructural level. We were able to confirm the central role of T8 lymphocytes being the predominant type of lymphocytes in close contact with liver cells in the space of Disse. A certain percentage of these cells expressed "activation" markers as IL-2 receptor, TA1 and T11/3. In acute hepatitis, the NK lymphocytes made up a fifth of all lymphocytes, whereas their number dropped below 10% in the chronic stage. There was a vague correlation between the inflammatory activity of the disease and the expression of HLA antigens (both classes I and II) on inflammatory cells and also on hepatocytes. The results did not show significant differences between hepatitis B and non-A, non-B.(ABSTRACT TRUNCATED AT 250 WORDS)

A possible cytotoxicity inducer role of 5/9 positive lymphocytes infiltrating the liver in CAH patients

The presence, in chronic active hepatitis (CAH) patients, of an inflammatory infiltrate basically composed of T lymphocytes suggested the hypothesis that these lymphocytes could play a role in the pathogenesis of the disease. The aim of this study has been to characterize, in a group of carefully selected CAH patients, the liver-infiltrating T lymphocyte, utilizing commercial monoclonal antibody (anti-Leu 1, anti-Leu 2a, anti-Leu 3a) and 5/9 monoclonal antibody that recognizes a further lymphocyte subset within T4 cells. Our data show that both T4 positive subpopulation and T8 positive subpopulation are represented in the infiltrate in the same ratio; furthermore the distribution of 5/9 positive lymphocytes is prevalent where the infiltrate is mainly composed of T8 positive lymphocytes. Moreover, there is a positive correlation between 5/9 positive cells in the liver and GPT and the patients with high percentages of infiltrating 5/9 positive lymphocytes show a low T4/T8 ratio with respect to patients with low percentages of 5/9 positive cells. These data support the hypothesis that 5/9 positive lymphocytes may present an inducer role on cytotoxic cells.

Immunology of primary biliary cirrhosis

(1) The serological diagnosis of PBC is possible in almost 100% of cases when appropriate methods and specific antigen preparations are used such as the purified ATPase fraction by ELISA for the detection of anti-M2, sonicated mitochondria by immunodiffusion for the demonstration of precipitating antibodies against M-A or M-B, and cell cultures by immunofluorescence for the detection of antibodies against nuclear dots. (2) The establishment of AMA profiles obtained by ELISA and CFT seems to be a sensitive approach to a better definition of the natural course of PBC. A distinction between a rather benign and a more progressive course seems especially possible in the presence of the AMA profiles A and B (anti-M9 and/or anti-M2-positive only by ELISA) versus D (anti-M2-, anti-M4-, anti-M8-positive in the CFT). (3) The analysis of cellular immune reactions in vitro and in vivo suggests an activation of cytotoxic T cells as well as a defect in the function of T suppressor cells. (4) Although the aetiology of PBC is unknown, the detection of MHC Class II antigens on bile duct epithelial cells in liver biopsies of patients with PBC but not of normal individuals may imply that an infectious agent being exposed in association with these MHC structures may trigger the disease. The inability of the immune system in controlling this infectious process would then lead to an ongoing inflammatory reaction which is responsible for the continuous destruction of bile ducts within portal triads.

In situ characterization of the cell-surface antigens of the mononuclear cell infiltrate and bile duct epithelium in primary biliary cirrhosis

To analyze the tissue distribution of mononuclear cells and HLA antigens in primary biliary cirrhosis, we studied liver biopsies of 12 patients at different stages of the disease, using the avidin-biotin-peroxidase technique and monoclonal antibodies directed against T and B lymphocytes, T-cell subsets, macrophages, NK/K cells, dendritic cells, and HLA class I and II antigens. To evaluate the proportion of activated T cells we used anti-interleukin-2-receptor antibodies and a double-staining technique for T cells and class II HLA antigens. In all biopsies activated T cells predominated in the portal areas and around the damaged bile ducts. T4 cells almost always outnumbered T8 cells. While B cells, NK/K cells, and dendritic cells were always scarce, macrophages constituted about 30% of the cellular infiltrate. Biliary epithelium, which normally expresses HLA class I antigens, displayed mainly HLA class II antigens. The predominance of T4 cells around the bile ducts, which express class II antigens, suggests that class II-restricted T4 lymphocytes may mediate liver damage in primary biliary cirrhosis.

PLP fixation for combined routine histology and immunocytochemistry of liver biopsies

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Immunohistochemical characterization of inflammatory infiltrates at the site of bile duct injury in primary biliary cirrhosis

Surgically obtained liver specimens from four patients with primary biliary cirrhosis (PBC), Stages I-II, were studied immunohistochemically using a broad panel of monoclonal antibodies. At the site of bile-duct injury (CNSDC), the inflammatory cells were recognized to be Coulter T-11+ (directed against all T-cells) and OKT-8+ (directed against cytotoxic/suppressor: C/S T-cells) cells. The MHC-class I antigen (i.e. HLA-A, B, C) was expressed weakly in the cytoplasm of the minority of damaged bile-duct epithelial cells, and the MHC-class II antigen (i.e. HLA-DR) was not expressed. Thus, OKT-8+ cells may play an important role in the immunologically mediated destruction of ductular epithelium in PBC. Strong MHC-antigen expression and OKT-8+ cell infiltration in destructive bile-duct lesions were not simultaneously observed. In the portal lymphocyte-rich areas, OKT-4+ (directed against helper/inducer: H/I T-cells) predominated over OKT-8+ cells. B-lymphocytes were present predominantly in the peripheral zones of the lymphoid aggregates. The distribution of helper/inducer T-cells and B-lymphocytes indicates that they may play a role in the induction of immunoglobulin in the lymphocyte-rich areas. The inflammatory mononuclear cells within the granuloma observed in one patient were Coulter T-11+, OKT-8+ and Leu-3a+3b+ (directed against helper/inducer T-cells) cells.

Cyclosporin, a new treatment for autoimmune chronic active hepatitis

A 51-year-old man whose aggressive autoimmune chronic active hepatitis had been treated with prednisone for five years, was treated with cyclosporin for 12 months. The disease had become unresponsive to high doses of prednisone and the side-effects had become disabling. Azathioprine could not be used because of drug hypersensitivity. With cyclosporin therapy the patient's symptoms disappeared for the first time since the onset of his illness, his liver enzyme levels fell almost to normal values and virtually no side-effects occurred. We suggest that cyclosporin be used on a clinical trial basis in patients with autoimmune chronic active hepatitis that is resistant to prednisone and azathioprine therapy.

Immunoregulatory T cell subsets in chronic hepatitis B virus infection: the influence of homosexuality

The purposes of this study were 2-fold: (i) To enumerate peripheral immunoregulatory T cell subsets in untreated patients with chronic hepatitis B virus (HBV) infection and (ii) to examine the relationship between disturbances in the balance of lymphocyte subsets with liver disease and the presence of homosexuality. Circulating T lymphocyte subsets were evaluated by monoclonal antibodies to the following cell antigens: OKT3 (total T cells), OKT4 (helper/inducer T cells), and OKT8 (suppressor/cytotoxic T cells). The following groups of subjects were examined: (i) 16 heterosexuals with HBV-associated chronic active hepatitis (CAHB); (ii) 10 heterosexual, healthy HBsAg carriers, and (iii) 16 male homosexuals with CAHB. Controls included 51 healthy heterosexuals and 12 healthy, noninfected male homosexuals. We were able to demonstrate that heterosexuals with CAHB had T4/T8 ratios which did not differ from those of noninfected heterosexuals. Both healthy carriers and healthy homosexuals, however, exhibited significantly lower T4/T8 ratios than did noninfected heterosexuals (p less than 0.05, p less than 0.01, respectively). In addition, homosexuals with CAHB had lower (1.5 +/- 0.1) T4/T8 ratios than did heterosexuals with CAHB (2.0 +/- 0.2). A possible mechanism for these findings is discussed. The data indicate that the presence of homosexuality may be an important factor to consider when evaluating immunoregulatory subsets in CAHB.

Tissue distribution of lymphocytes in rheumatic heart valves as defined by monoclonal anti-T cell antibodies

Fresh cardiac valvular tissues and atrial appendages removed from 106 Indian patients with rheumatic heart disease at the time of corrective cardiac surgery were examined to determine the characteristics of valvular interstitial lymphocytic infiltrates using conventional histologic staining along with indirect immunofluorescent techniques. Precise identification of the phenotypic profiles of inflammatory mononuclear cells was attempted using anti-IgG, anti-Ia, and monoclonal mouse hybridoma reagents identifying T cells (OKT3) as well as T cell subsets (OKT4 helper/inducer and OKT8 suppressor/cytotoxic cells). A similar group of 21 patients undergoing cardiac valvular resection in Albuquerque was studied. The mean age of Indian patients providing valve tissues was 27.7, whereas in those in Albuquerque, it was 52 years. Twenty-five percent of rheumatic heart valves in Indian patients showed significant interstitial lymphoid infiltrates, and one third of the rheumatic valves from patients in Albuquerque showed similar mononuclear cell collections. Lymphoid infiltrates contained a predominance of T cells (70 to 80 percent) and only occasional B cells. Most of the T cells were OKT4-positive, with only a minor representation of suppressor/cytotoxic OKT8-positive T cells. In many instances, OKT4-positive helper T cell collections were closely juxtaposed to fibroblasts and collagen fibrils. These findings suggest that the chronic rheumatic scarring process may involve helper/inducer T cells as an ancillary factor in the indolent contracture and fibrosis of deformed cardiac valvular structures. Attempts to demonstrate residual streptococcal antigens by indirect immunofluorescence using a wide panel of heterologous rabbit F(ab')2 reagents with specificity for group A streptococcal membranes, cell wall mucopeptide, or group A carbohydrate gave negative results.

Lymphocytes and Langerhans cells in the human oesophageal epithelium

Using monoclonal antibodies on fresh frozen endoscopically obtained oesophageal biopsies the distribution of Langerhans cells, B lymphocytes, and various subpopulations of T lymphocytes was studied in the normal human oesophageal mucosa and in oesophagitis. Identification of the lymphocytes was carried out by an immunoperoxidase technique using OKT3 (antihuman T cell antibody), OKT4 (antihuman helper T cell antibody), OKT8 (antihuman cytotoxic T cell) and OKT10 (antihuman null cell antibody). Identification of the Langerhans cells was carried out using an ATPase stain and OKIa (Ia like antigen) and OKT6 (antihuman thymocyte). In the normal oesophageal epithelium cytotoxic T lymphocytes are found as well as Ia positive Langerhans cells. Helper T lymphocytes and B lymphocytes are present mainly in the lamina propria. In oesophagitis an increase in Langerhans cells and cytotoxic T lymphocytes within the epithelium is found. From these findings it can be concluded that the oesophagus contains a reticuloepithelial system as well as a lymphocytic population which are a part of the gut-associated lymphoid tissue.