HCV RNA Genomic sequences and HCV-E2 glycoprotein in sural nerve biopsies from HCV-infected patients with peripheral neuropathy.

AIMS: Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications. METHODS: We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively. RESULTS: Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients. CONCLUSIONS: These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms.

Activation-induced cytidine deaminase in B cells of hepatits C virus-related cryoglobulinaemic vasculitis.

Immunoglobulin variable region heavy chain (IgVH ) somatic gene diversification is instrumental in the transformation process that characterizes hepatitis C virus (HCV)-related B cell lymphoproliferative disorders. However, the extent to which activation-induced cytidine deaminase (AID), an enzyme essential for IgV gene somatic hypermutation (SHM), is active in cryoglobulinaemic vasculitis (CV) remains unclear. AID mRNA expression in the peripheral blood of 102 chronically hepatitis C virus (HCV)-infected patients (58 with and 44 without CV) and 26 healthy subjects was investigated using real-time reverse transcription-polymerase chain reaction (RT-PCR). The features of activation-induced cytidine deaminase (AID) protein and mRNA transcripts were explored in liver tissue biopsies and portal tracts isolated using laser capture microdissection. In chronically HCV-infected patients, AID mRNA expression was almost threefold higher in those with than in those without CV and sevenfold higher than in healthy subjects (median-fold: 6.68 versus 2.54, P = 0.03 and versus 0.95, P = 0.0003). AID transcript levels were significantly higher in polyclonal than in clonally restricted B cell preparations in either CV or non-CV patients (median-fold, 15.0 versus 2.70, P = 0.009 and 3.46 versus 1.58, P = 0.02, respectively). AID gene expression was found to be related negatively to age and virological parameters. AID protein was found in portal tracts containing inflammatory cells that, in several instances, expressed AID mRNA transcripts. Our data indicate that the aberrant expression of AID may reflect continuous B cell activation and sustained survival signals in HCV-related CV patients.

Multidisciplinary approach for HCC patients: hepatology for the oncologists.

Hepatocellular carcinoma (HCC) is a complex and heterogeneous disease, often associated with underlying conditions, like cirrhosis or other relevant co-morbidities that worsen the prognosis and make the clinical management more challenging. Current recommendations emphasize the importance of a multidisciplinary approach for the management of HCC patients and stress the crucial role of careful prevention and the management of cirrhosis-associated complications. This article discusses the importance of a multidisciplinary approach in the treatment of HCC patients. Current recommendations for the treatment of cirrhotic patients with HCC are also reviewed.

T cell receptor variable ß gene repertoire in liver and peripheral blood lymphocytes of chronically hepatitis C virus-infected patients with and without mixed cryoglobulinaemia.

To characterize the repertoire of T lymphocytes in chronically hepatitis C virus (HCV)-infected patients with and without mixed cryoglobulinaemia (MC). T cell receptor (TCR) variable (V) ß clonalities in portal tracts isolated from liver biopsy sections with a laser capture microdissection technique in 30 HCV-positive MC patients were studied by size spectratyping. Complementarity-determining region 3 (CDR3) profiles of liver-infiltrating lymphocytes (LIL) were also compared with those circulating in the blood. The representative results of TCR Vß by CDR3 were also obtained from liver tissues and peripheral blood lymphocytes (PBL) of 21 chronically HCV-infected patients without MC. LIL were highly restricted, with evidence of TCR Vß clonotypic expansions in 23 of 30 (77%) and in 15 of 21 (71%) MC and non-MC patients, respectively. The blood compartment contained TCR Vß expanded clones in 19 (63%) MC and 12 (57%) non-MC patients. The occurrence of LIL clonalities was detected irrespective of the degree of liver damage or circulating viral load, whereas it correlated positively with higher levels of intrahepatic HCV RNA. These results support the notion that TCR Vß repertoire is clonally expanded in HCV-related MC with features comparable to those found in chronically HCV-infected patients without MC.

High circulating chemokines (C-X-C motif) ligand 9, and (C-X-C motif) ligand 11, in hepatitis C-associated cryoglobulinemia.

(C-X-C motif) ligand 9 and (C-X-C motif) ligand 11 (CXCL9 and CXCL11), are potent chemoattractants for activated T cells, and play an important role in T helper 1 (Th)1 cell recruitment in chronic hepatitis C. No study has evaluated CXCL9, together with CXCL11, circulating levels in patients with mixed cryoglobulinemia and hepatitis C (MC+HCV-p). The aim of the present study therefore was to measure serum CXCL9, and CXCL11 levels, in MC+HCV-p, and to relate the findings to the clinical phenotype. Serum CXCL9 and CXCL11 were measured in 71 MC+HCV-p and in matched controls. MC+HCV-p showed significantly higher mean CXCL9 and CXCL11 levels than controls (P less than 0.001, for both), in particular, in 32 patients with active vasculitis (P less than 0.001). By defining high CXCL9 or CXCL11 level as a value of at least 2 SD above the mean value of the control group ( greater than 100 pg/mL): 89 percent MC+HCV-p and 5 percent controls had high CXCL9 (P less than 0.0001, chi-square); 90 percent MC+HCV-p and 6 percent controls had high CXCL11 (P less than 0.0001, chi-square). In a multiple linear regression model of CXCL9 vs age, ALT, CXCL11, only CXCL11 was significantly (r = 0.452, P less than 0.0001) and independently related to CXCL9. Our study demonstrates in MC+HCV-p vs controls: (i) high serum CXCL9, and CXCL11, significantly associated with the presence of active vasculitis; (ii) a strong relationship between circulating CXCL9 and CXCL11. Future studies on a larger cohort of patients are needed to evaluate the relevance of serum CXCL9 and CXCL11 determination as clinico-prognostic marker of MC+HCV.

Preliminary classification criteria for the cryoglobulinaemic vasculitis.

BACKGROUND: To develop preliminary classification criteria for the cryoglobulinaemic syndrome or cryoglobulinaemic vasculitis (CV). METHODS: Study part I developed a questionnaire for CV to be included in the formal, second part (study part II). Positivity of serum cryoglobulins was defined by experts as an essential condition for CV classification. In study part II, a core set of classification items (questionnaire, clinical and laboratory items, as agreed) was tested in three groups of patients and controls-that is, group A (new patients with the CV), group B (controls with serum cryoglobulins but lacking CV) and group C (controls without serum cryoglobulins but with features which can be observed in CV). RESULTS: In study part I (188 cases, 284 controls), a positive response to at least two of three selected questions showed a sensitivity of 81.9% and a specificity of 83.5% for CV. This questionnaire was employed and validated in study part II, which included 272 patients in group A and 228 controls in group B. The final classification criteria for CV, by pooling data from group A and group B, required the positivity of questionnaire plus clinical, questionnaire plus laboratory, or clinical plus laboratory items, or all the three, providing a sensitivity of 88.5% and a specificity of 93.6% for CV. By comparing data in group A versus group C (425 controls), the same classification criteria showed a sensitivity 88.5% and a specificity 97.0% for CV. CONCLUSION: Classification criteria for CV were developed, and now need validation.

Current and emerging therapeutic approaches in HCV-related mixed cryoglobulinemia.

Recognition of hepatitis C virus (HCV) as an etiological factor in mixed cryoglobulinemia (MC) has dramatically changed our point of view in its treatment. Emphasis is placed on abatement and clearance of viral load and deletion of clonal expansions of IgM molecules with rheumatoid factor activity-synthesising B cells. The purpose of this review is to discuss the underlying scientific rationale and results of clinical studies of new treatment approaches to MC, with a focus on cell-depleting therapies and chemokine blockade. Additional antiviral agents directed to several phases of HCV life cycle acting with different or alternate mechanisms are proposed with the goal to enhance response rates more broadly suitable for MC patients with vasculitis and peripheral neuropathies. The majority of the available data on these new treatment approaches stems from open-label studies, but controlled trials are under way. Therapy directed against chemokines and/or cytokines represents an interesting and promising future target.

Double-filtration plasmapheresis in the treatment of leg ulcers in cryoglobulinemia.

Hepatitis C virus (HCV) is the major cause of cryoglobulinemia. Skin lesions are frequent and can be cured from the removal of cryoglobulins by therapeutic apheresis. We describe a case of HCV-positive type I cryoglobulinemia with severe leg ulcers, not responsive to antiviral and immunosuppressive treatment. Thirty sessions of double filtration plasmapheresis were performed, over a period of 6 months, with no other associated treatment. Before and after each session an assessment of immunoglobulins, complement, cryocrit, and fibrinogen was made. HCV RNA levels were determined in serum cryoprecipitate, supernatant before and after each session, and in the collection bag. No differences in pre and postapheresis values were observed in the serum concentrations and the supernatant, whereas the postapheresis cryoprecipitate showed a significantly reduced viral load (P < 0.02) as compared with the preapheresis values. There was improvement in the condition of ulcers in the leg during apheresis and had completely regressed by the end of the cycle.

HCV-NS3 and IgG-Fc crossreactive IgM in patients with type II mixed cryoglobulinemia and B-cell clonal proliferations.

We demonstrate that in three cases of MC (two with immunocytoma), the IgM-RF+ component of their cryoprecipitated represents the circulating counterpart of the B-cell receptor (BCR) of the monoclonal overexpanded B-cell population. These IgMs were isolated and used to demonstrate a crossreactivity against both hepatitis C virus (HCV) NS3 antigen and the Fc portion of IgG. Epitopes were identified in a fraction of exemplary samples by using epitope excision approach (NS(31250-1334) and IgG Fc(345-355)). The same phenomenon of crossreactivity has been shown to occur in vivo after immunization of a mouse with the NS3(1251-1270) peptide. To verify if the same reaction was also present in MC samples characterized by an oligo/polyclonal B-cell proliferation, IgM crossreactivity was tested in 14 additional samples. Five out of the 14 were reactive against HCV NS3 and 11 out of 14 were reactive against IgG-Fc peptide. The data support the role of HCV NS3 antigen in a subset of patients with MC, whereas the high frequency of the IgG-Fc epitope suggests that these B cells originate from precursors strongly selected for auto-IgG specificity. We suggest that engagement of specific BCRs by NS3 (or NS3-immunocomplex) antigen could explain the prevalence of IgM cryoglobulins in these patients.

An enzyme-linked immunosorbent assay for the detection of autoantibodies to albumin.

The development of an enzyme-linked immunosorbent assay (ELISA) for anti-albumin autoantibodies (AAA), using immobilized monomeric or glutaraldehyde-polymerized human, bovine or egg albumin, is described. Major problems in detection by the ELISA of AA against human albumin (HSA) were due to high 'non-specific' binding with the commercial anti-human immunoglobulin antisera used and to interference by IgM/HBs circulating complexes. However, it was found that AAA are not species-specific and that these problems may be overcome using immobilized bovine (BSA) or egg (EggA) albumin. AAA were found to have a similar affinity for BSA as for HSA but slightly lower for EggA, while AAA affinities for the monomeric forms were lower than for the corresponding polymeric albumins. All sera from the 28 normal subjects tested were found to contain both IgM- and IgG-AAA. Patients with acute hepatitis B (n = 23) had significantly lower titres of IgM-AAA than normal subjects, as did chronic HBV carriers with (n = 33) or without (= 17) underlying liver disease, while IgG-AAA titres were reduced only in the acute hepatitis patients. These findings support the concept that AAA have a normal physiological function (probably for removal of effete albumin molecules) and that, in HBV infection, there is a decrement in titres that may be related to the clearance of the virus.

Detection of receptors for polymerised human albumin by immunoperoxidase and immunoadherence in liver tissue of HBsAg chronic carriers.

Receptors for polymerised human albumin (pHSA-Rs) were detected in unfixed cryostat sections from HBsAg chronic carriers using direct immunoperoxidase and immunoadherence methods. Although pHSA-Rs were detected by both methods, the receptors detected by immunoperoxidase were associated with HBV and showed properties different from the receptors detected by immunoadherence. The double immunocytochemical staining which detected contemporaneously pHSA-Rs and HBsAg in the same cell showed that there are two types of infected hepatocytes: one capable of synthesizing pHSA-Rs and HBsAg and the other capable of synthesizing only HBsAg. The intrahepatocyte synthesis of pHSA-Rs does not correlate with the severity of chronic liver disease or with the presence of tissue HB core antigen.

Cytoplasmic localization of hepatitis B core antigen in hepatitis B virus infected livers.

Routine use of commercially available antisera against hepatitis B core antigen (HBcAg) obtained from Escherichia coli transfected with HBV-DNA, has permitted a re-evaluation of the histochemical distribution of the antigen in liver tissue. HBcAg, classically described almost exclusively in the nucleus, was found with a very high frequency in the cytoplasm of liver cells. Our data indicate, however, that formalin fixation and paraffin embedding destroy part of HBcAg antigenicity and eliminate most of its cytoplasmic expression. HBcAg was found in 6/7 (85.7%) of HBsAg/HBeAg positive subjects, and in 2/12 (16/6%) of HBsAg/anti-HBe positive subjects; in both subgroups the cytoplasmic expression of the antigen correlated with the presence of circulating hepatitis B virus-deoxyribonucleic acid (HBV-DNA).

Granulocytopenia after combined therapy with interferon and angiotensin-converting enzyme inhibitors: evidence for a synergistic hematologic toxicity.

PURPOSE: The purpose of this study was to assess whether granulocytopenia observed in 3 of 38 patients with essential mixed cryoglobulinemia who were treated with low-dose interferon was due to the underlying disease or to synergistic toxicity of interferon with other drugs. PATIENTS AND METHODS: Adverse effects of interferon therapy were monitored in 38 patients affected with type II essential mixed cryoglobulinemia. Patients were treated with 3 million units (MU), daily or on alternate days, of recombinant interferon-alpha 2a (35 patients) or with natural interferon-beta (3 patients). The duration of treatment ranged between 6 and 15 months; the total duration of follow-up, including after therapy, ranged between 8 and 93 months. RESULTS: None of 35 patients treated with interferon alone developed significant hematologic alterations. In addition, none of 7 patients treated with angiotensin-converting enzyme (ACE) inhibitors alone showed hematologic toxicity. Three patients who were treated with a combination of interferon and ACE inhibitors developed severe granulocytopenia a few days after starting treatment. Granulocytopenia subsided within 1 to 2 weeks after suspending therapy. Resumption of treatment with this drug combination produced a granulocytopenia relapse in 1 patient. In these 3 patients, interferon treatment alone, or ACE inhibitor monotherapy, was not followed by granulocytopenia. CONCLUSION: Although severe hematologic toxicity rarely develops in patients treated with low-dose interferon, granulocytopenia occurred in all 3 of our patients with mixed cryoglobulinemia who were treated with a combination of low-dose interferon-alpha 2a and ACE inhibitors. Neither drug alone was toxic in any of our cryoglobulinemic patients, indicating a high risk of severe hematologic toxicity for this drug combination, at least in patients with this disease. Physicians should be aware of this danger when using interferon treatment in patients with this, or possibly other, disorder(s) that also require antihypertensive therapy.

Demonstration of HBsAg as the antigen component in circulating immune complexes detected by peg-solid phase test.

The development of an enzyme-linked immunosorbent assay to identify HBsAg as the antigen component within circulating immune complexes using immobilized polyethylene glycol (PEG) is described. The method utilizes, on one hand, the ability of PEG to bind stably to plastic supports and, on the other, to precipitate circulating macromolecules. This method is easily performed, very cheap, quick and, above all, it helps define the biological nature of the immune complexes. HBsAg can be revealed as the antigen component of HBsAg/anti-HBs soluble immune complexes at concentrations of at least 20 ng/ml and either in antigen or antibody excess. Our results indicate that HBsAg circulates in a complexed form in 47% of HBsAg chronic carriers and in 10.7% of patients with liver disease who are positive for serum antibody to hepatitis B surface antigen (anti-HBs) and to core antigen (anti-HBc). None of the other groups of patients in the study had circulating HBsAg in the complexed form.

Hepatitis C virus infection, mixed cryoglobulinemia, and non-Hodgkin's lymphoma: an emerging picture.

Hepatitis C virus (HCV) is a single-stranded RNA agent which expresses its genetic informations in the form of a single, large polyprotein encoded by an open reading frame (ORF) that extends through most of its genomic RNA. Proteolytic cleavage of the ORF product is essential for the virogenesis and the production of viral progeny. HCV is responsible for chronic liver disease, cirrhosis and possibly hepatocellular carcinoma. Viral persistence is considered the greatest problem in the management of HCV infection. It may result from several mechanisms, two of which are established. In the first, the high rate of genetic variations during viral replication results in the production of mutants capable of escaping the immune attack. In the second, the virus infects cells of the immune system itself, which represent a privileged site that cannot be reached by virus-specific T cell response. Involvement of lymphoid cells in the early stages of HCV infection may provide insight into the pathobiologic patterns of extrahepatic dissemination (lymph nodes, major salivary glands, kidneys, blood vessels). Dissemination of HCV-infected lymphoid cells throughout the organism is likely to maintain a mobile and extensive reservoir of the virus. In this respect, extrahepatic sites may act as a source of continuous reinfection of hepatocytes. Studies of intrahepatic B lymphocytes indicate that they are infected with HCV, clonally expanded and activated to secrete IgM molecules with rheumatoid factor activity. This strongly suggests that HCV directly stimulates B cell expansion, which may result in an indolent stage of lymphoproliferation (i.e., mixed cryoglobulinemia) or in frank B cell non-Hodgkin's lymphoma (NHL). The frequency of NHL, however, is much lower than that of HCV infection, suggesting that HCV alone is not able to induce tumors and that cellular events, in addition to the presence of virus and virus-encoded products, are necessary in order to obtain a malignant B cell phenotype. The demonstration of HCV productive infection in bone marrow-recruited and circulating pluripotent hematopoietic CD34+ stem cells indicates that HCV replication occurs in the early differentiation stages of hematopoietic progenitors. These are stable cell populations and are likely to represent the initial site of infection and a continuous source of virus production.

Mixed cryoglobulinemia as a model of systemic vasculitis.

Leukocytoclastic vasculitis is the dominant lesion of mixed cryoglobulinemia (MC). The high prevalence of antibodies to hepatitis C virus (HCV) in association with the higher concentration of HCV RNA genomic sequences in the cryoglobulins suggests a close relationship between MC and HCV infection and strongly supports the view that this virus plays a key role in causing vascular damage. Analysis of the composition of immune complexes (ICs) provides evidence that cryoglobulins include virions mostly bound to IgG that is specifically reactive with HCV-related proteins, which in turn are crosslinked by monoclonal IgM with rheumatoid factor (RF) activity, frequently bearing the WA crossidiotype (XId). This structure is similar (if not identical) to that of circulating ICs from HCV-infected patients without cryoglobulins, suggesting that the virus may be directly responsible for the production of WA RF. Evidence for the role of circulating cryoproteins in the pathogenesis of cutaneous and renal vasculitis stems from the demonstration of HCV-related proteins and/or HCV RNA genomic sequences in the vessel wall of patients with MC. Our data indicate that endothelial cells are fully susceptible to infection by and replication of HCV, and support the contention that they serve as sufficient targets for the binding of HCV proteins expressed on the cell surface to serum immunoglobulins. The in situ demonstration of IgM RF WA XId adds further evidence that RF of the WA group participates in the development of vasculitis and probably stabilizes the binding of IgG antibodies. Lymphocytes may be crucial in the infection of endothelial cells by acting as a circulating viral reservoir. After encouraging initial results, controlled trials have defined the substantive efficacy of IFN-alpha in the treatment of MC. A response of IFN can be achieved in more than 50% of patients and includes improvement of cutaneous vasculitis and renal function. This clinical response is accompanied by a reduction in hepatitis C viremia, serum cryoglobulin concentration, and IgM RF synthesis. However, almost 80% of responders eventually have a clinical and biochemical relapse. Additional studies are required to improve the outcome and extension of this therapy, define the best candidates, and indicate the situations in which it is needed.

Immunohistochemical detection of hepatitis C virus-related proteins in liver tissue.

OBJECTIVE: Hepatitis C virus (HCV)-associated antigens (Ags) are hard to detect and poorly defined in liver tissue, and are of uncertain interpretation. The failure of immunohistochemistry in HCV infection may be due to the affinity of specific antisera, the levels of Ags in infected tissues, the labile and unstable expression of antigenic determinants, and the use of fixatives that may alter or destroy viral epitopes. Strategies to optimize all stages of tissue specimen processing have therefore been devised in the liver biopsies of patients with acute and chronic hepatitis, and those with hepatocellular carcinoma (HCC). METHODS: HCV-Ags were detected with a two-stage indirect immunostaining procedure on unfixed cryostat liver sections from 7 acute and 23 chronic HCV-infected patients, and from 4 patients with HCV-associated HCC. A mixture of monoclonal antibodies directed to structural and non-structural HCV-related proteins were used as the primary reagents. RESULTS: HCV-Ags in 50-70% of the hepatocytes were found in all seven acute hepatitis patients compared with < or = 20% hepatocytes (P < 0.05) in 10 out of 23 patients (43.5%) with chronic hepatitis. Immunoreactive signals appeared as diffuse or coarse granular deposits in the cytoplasm only. The nuclei were unstainable. No clear membranous pattern was found, although fine granular, submembranous accumulation in distinct areas of the cytoplasm was observed. In acute hepatitis, HCV-Ag positive hepatocytes were distributed in the lobules in direct relation to the areas of necrosis and inflammatory cell accumulation, whereas in chronic hepatitis the immunoreactive cells were not clearly related to the necrotic foci. HCV-Ag immunodeposits were demonstrated in all patients with HCC. The immunoreactive signal in neoplastic cells was primarily located in the cytoplasm and rarely in the nuclei. As compared with the non-neoplastic zones, neoplasia demonstrated a significantly higher specific signal. CONCLUSIONS: Immunohistology is a powerful tool for the identification of HCV-related proteins in liver tissue. Sensitivity was significantly enhanced by the use of fresh-frozen tissues, which presumably preserve their HCV antigen structure, and by a mixture of monoclonal antibodies directed against HCV-related proteins, possibly on account of the separate access of each probe to different target proteins. The demonstration of HCV infection in hepatocyte cytoplasm indicates that this is the primary site of HCV replication, while its presence in malignant cells suggests that the virus could be substantially involved in the pathogenesis of HCC.

Hepatitis C virus infection and clonal B-cell expansion.

The striking association between hepatitis C virus (HCV) infection and the so-called "essential" mixed cryoglobulinemia (MC) has led to the hypothesis that HCV plays a major role in the production of cryoglobulins. Analysis of soluble and cryoprecipitable immune complexes shows that the hepatitis C virion is bound to IgM bearing the WA cross-idiotype (XId). The production of WA XId IgM seems to be the result of chronic stimulation by HCV of a population of WA XId + CD5 + B cells. It is possible that the reactivity of WA XId IgM does not initially include rheumatoid factor (RF) activity, which may be acquired secondarily from mutational events accompanying a probably T-cell independent B cell proliferation. Type II MC is a benign proliferation that progresses to malignancy in a minority of patients. This is consistent with the concept that malignancy progression involves the accumulation of multiple mutations of proto-oncogenes and tumor suppressor genes that are facilitated by chronic antigenic stimulation. The recent demonstration of HCV in hyperplastic reactive lymphoadenopathy and in the neoplastic lymph nodes of patients with MC strengthens the putative role played by HCV in lymphomagenesis. A fuller understanding of the virus-related mechanisms of lymphoproliferation in MC patients would contribute significantly to the development of therapeutic strategies.

Binding and receptors for human albumin polymers and IgM/HBs circulating complex in HBsAg chronic carriers.

Binding activity for polymerized human serum albumin (pHSA-binding), studied in passive haemoagglutination, receptors for polymerized human serum albumin (pHSA-receptors), studied in ELISA, as well as the circulating IgM/HBs complex were tested in 71 chronic carriers of HBsAg with and without liver pathology. We found that 73.2% of the sera were reactive for pHSA-binding while 45% were reactive for pHSA-receptors and 42.2% for the circulating IgM/HBs complex. The distribution and mode of association of these 3 markers showed a close correlation with the e-antigen in circulation (HBeAg) and with liver disease (p less than 0.05). We further observed that pHSA-binding can be present in the absence of pHSA-receptors, suggesting the possible existence of further reactants in the serum-pHSA reaction. We did not observe any correlations between the circulating IgM/HBs complexes, pHSA-binding and pHSA-receptors. Blocking experiments, in fact, confirmed the non-involvement of polymerized human serum albumin in the formation of the circulating IgM/HBs complex. Elution experiments showed that, in addition to HBsAg, class-G immunoglobulins are also directly involved in the serum-pHSA reaction.

Autoantibody to albumin of type G and M in acute and chronic viral hepatitis.

Autoantibodies to albumin (AAA) were tested by an ELISA method in patients with A, B and NANB acute and chronic hepatitis, and in a control group. AAA-IgM had a different behaviour in acute hepatitis type A, in which we observed a high average titre as compared with B, and NANB hepatitis, in which we observed a decrease in the average titre. In the chronic phase, we noted a decrement of the average titre in all the types of hepatitis. For AAA-IgG, in the acute phase the average titre in hepatitis A, B and NANB was lower than in the control group. In the chronic stage, only NANB hepatitis showed a decrement of the average titre of the antibody. On the base of these results, we can say that the involvement of AAA seems to be different in hepatitis A from the other two types, in which the decrement of average titre may be explained by the formation of immunocomplexes which are not detected by this test.