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CD4+ T cells have been shown to be crucial for the induction and maintenance of cytotoxic T cell responses and to be also capable of mediating direct tumor rejection. Therefore, the anticancer therapeutic efficacy of peptide-based vaccines may be improved by addition of HLA class II epitopes to stimulate T helper cells. Survivin is an apoptosis inhibiting protein frequently overexpressed in tumors. Here we describe the first immunological evaluation of a survivin-derived CD4+ T cell epitope in a multipeptide immunotherapy trial for prostate carcinoma patients. The survivin peptide is promiscuously presented by several human HLA-DRB1 molecules and, most importantly, is naturally processed by dendritic cells. In vaccinated patients, it was able to induce frequent, robust and multifunctional CD4+ T cell responses, as monitored by IFN-γ ELISPOT and intracellular cytokine staining. Thus, this HLA-DR restricted epitope is broadly immunogenic and should be valuable for stimulating T helper cells in patients suffering from a wide range of tumors. [ABSTRACT FROM AUTHOR]

Background and Aims Recently, a non-M2-related mitochondrial 60 kDa protein found to be recognized by antimitochondrial antibody ( AMA) negative sera from patients with primary biliary cirrhosis ( PBC) has been shown to contain parts of the five F1- ATPase subunits α, β, γ, δ and ε. In this study, we examined whether this enzyme is, indeed, a target antigen in PBC. Methods Analysed were 60 AMA-positive/anti-M2-negative and 103 anti-M2-positive PBC patients, 46 patients with autoimmune hepatitis ( AIH), 35 patients with primary sclerosing cholangitis ( PSC), 110 patients with viral hepatitis, 40 patients with inflammatory bowel diseases ( IBD), 33 patients with connective tissue diseases (systemic lupus erythematosus, mixed connective tissue disease, Sjögren disease, systemic sclerosis) and 25 blood donors. The F1- ATPase-subunits α-δ were recombinantly expressed in E scherichia coli, purified and applied to ELISA and Western blotting. Results In all, 40 of the 60 AMA-positive/anti-M2-negative (67%) and 44 (43%) of the 103 anti-M2-positive PBC-sera reacted with at least one of the F1-subunits α-δ. The β- and γ-subunits were preferentially recognized. However, also up to 57% of patients with AIH and 34% of patients with PSC had anti-β- or γ-antibodies, while patients with viral hepatitis had these antibodies in up to 13%. Patients with IBD had anti-β and anti-γ-antibodies in up to 20 and 5% respectively. None of the patients with connective tissue diseases had antibodies to the β- and only 6% to the γ-subunit. Sera from healthy blood donors were negative. Conclusions Antibodies to the β- and γ-subunits of F1- ATPase are further AMAs in PBC but occur also in other autoimmune liver disorders; they may be, therefore, indicators for a general autoimmune process of the liver. [ABSTRACT FROM AUTHOR]

Background: In primary biliary cirrhosis (PBC), autoreactivity mainly targets members of the pyruvate dehydrogenase complex (PDC). Because PDC subunits are expressed on the surface of mycoplasma and molecular mimicry may be one aetiological factor, we analysed the presence of mammalian and mycoplasma PDC-specific antibodies in PBC patients. Methods: Antibodies to porcine PDC and Mycoplasma pneumoniae (mp) antigens mpPDH-C (to be designated mpPDC-E2 chain), mpPDH-B (to be designated mpPDC-E1β chain), mpCARDS TX and mpP1 were investigated in sera from 43 PBC patients, 19 patients with autoimmune hepatitis and 11 healthy controls by an enzyme-linked immunosorbent assay and Western blotting. To study the rate of acute mycoplasma infection, an adhesin P1-specific polymerase chain reaction (PCR) was performed. Results: Immune reactivity to the mpPDC-E2 antigen was significantly enhanced in PBC patients (83.7%) as compared with controls (overall frequency of 36.7%), while antibodies to the porcine PDC-E2 chain were found only in PBC patients (88%) excluding a simple cross-reactivity of PDC-related antibodies. This observation was confirmed by inhibition studies demonstrating that porcine PDC did not inhibit mycoplasma PDC-specific antibodies and vice versa. The occurrence of antibodies to mpPDC seems to precede the occurrence of antibodies to porcine PDC. Infection with mycoplasma was equally distributed in the groups as evidenced by an antibody frequency comparable to CARDS TX and P1 and PCR reactivity. Conclusion: Because PBC patients show a significantly enhanced frequency of mpPDC-E2-related antibodies, besides other factors, molecular mimicry between surface molecules of mycoplasma and epitopes of the autoantigen may play a central role in the aetiopathology of PBC. [ABSTRACT FROM AUTHOR]

Primary biliary cirrhosis (PBC) is characterized by the presence of antimitochondrial antibodies (AMA). Autoantibodies specific for the mitochondrial M4 antigen can be detected by a complement fixation test (CFT) but not by immunoblotting. The aim of this study was to elucidate the identity of the M4 antigen. Patients and methods: M4 proteins were purified by affinity chromatography using IgG fractions of PBC marker sera being CFT positive ( n=5) or negative ( n=5) and identified by Western blotting, silver staining and sequence analysis. Further, a cohort of 57 PBC patients was tested for the reactivity to M4 and pyruvate dehydrogenase complex (PDC). Results: Two AMA patterns of the marker sera were visualized: CFT-positive sera were defined as PDC-E2+/E1+ and the CFT-negative sera as PDC-E2+/E1−. The major proteins in the M4 fraction could be related to the PDC-E1 subunits. A clear-cut association between anti-M4 reactivity in the CFT and the reactivity to both PDC subunits could also be documented in the cohort of 57 PBC patients showing anti-PDC-E1α and E1β antibodies at a frequency of 74% and 67%. Conclusions: CFT reactivity against M4 antigens could be preferentially identified as a reaction against PDC-E1. As PDC-E1 subunits as compared with PDC-E2 lack lipoyl-binding sites, they probably have to be considered as an independent and important target. [ABSTRACT FROM AUTHOR]

Primary biliary cirrhosis (PBC) is a cholestatic liver disease characterized by the presence of antimitochondrial autoantibodies (AMAs), but also with reactivities to other autoantigens. Recent studies showed that antibodies to phospholipids (APAs) represent an important group of autoantibodies identified in patients with PBC. In this study different types of APAs were identified in the sera of patients with PBC and autoimmune hepatitis (AIH) and control subjects. Sera from patients with PBC and AIH were tested for the presence of antibodies directed against cardiolipin (CL), phosphatidylserine (PS), and to β2-glycoprotein I (β2-GPI). Furthermore, an in-house test for antithromboplastin antibodies was performed. Antinuclear antibodies (ANAs) and antimitochondrial antibodies (AMAs) were tested with standard tests. IgM anti-PS antibodies were found in 75% of the 51 PBC patients, but only in 4% of the 48 AIH patients (P < 0.0001). IgM anti-CL antibodies were more frequently detected in AIH than in PBC (75% vs. 89%; P = 0.045). IgM anti-β2- GPI antibodies were observed more frequently in patients with AIH (83%) than with PBC (59%; P = 0.007). The APAs of the IgG type did not differ significantly between the groups of patients. Considering the clinical/laboratory parameters, the levels of alkaline phosphatase (P = 0.017), glutamate pyruvate transaminase (P = 0.035), and glutamate oxalacetate transaminase (P = 0.034) were significantly higher in PBC patients who were positive for IgM anti-PS antibodies than in the anti-PS antibody-negative patients. In conclusion, APAs are present in PBC patients with a higher level of the disease or more intense liver damage than in patients without APAs. Thus IgM anti-PS antibodies represent a new marker of activity in PBC patients. [ABSTRACT FROM AUTHOR]

In 1983, a female patient born in 1963 presented with symptoms of ulcerative colitis and typical clinical and histological signs of primary sclerosing cholangitis (PSC). At this time only pANCA were positive while other marker antibodies for autoimmune liver disorders could not be detected. In summer 1987 the clinical picture changed and was replaced by laboratory and histological signs typical of autoimmune hepatitis (AIH). Thus, IgG levels increased considerably and cholestatic enzymes became normal. For the first time, anti-liver-pancreas antibodies (LP), a diagnostic marker for AIH type III could be detected. In the following years several relapses occurred also induced by repeated discontinuation of immunosuppressive therapy. Symptoms of colitis persisted but signs of cholestasis remained absent for the following ten years. In 1997, colitis exacerbated again and colectomy had to be performed together with liver transplantation. Surprisingly, histology of the explanted liver now showed the typical features of PSC stage III/IV while the significant criteria for AIH were now lacking. Thus, progression to cirrhosis was, probably, mainly induced by the biliary destructive and fibrotic process although biochemical and serological data were clearly indicative of an autoimmune, i.e. AIH-related manifestation. [ABSTRACT FROM AUTHOR]

In recent retrospective studies, it was shown that subtypes of antimitochondrial antibodies (AMA) can help to discriminate between a benign [only anti-M9 and/or anti-M2 positive by enzyme-linked immunosorbent assay (ELISA)] and a rather progressive course (anti-M2, -M4 and/or -M8 positive). According to different constellations of these AMA subspecificities in ELISA and complement fixation test (CFT), four AMA profiles (A-D) were defined. In 1984 we started a prospective study based on 200 PBC patients with known AMA profiles in order to correlate the antibody pattern with the clinical outcome. Progression was defined primarily as the necessity of liver transplantation and death due to hepatic failure or variceal bleeding. At entry, 18 (9%) of the 200 patients had AMA profile A (only anti-M9), 57 (29%) profile B (only anti-M2 with or without anti-M9), 74 (37%) profile C (anti-M2 in association with anti-M4/-M8 by ELISA), and 51 (26%) profile D (anti-M2/-M4/-M8 by ELISA and CFT). At the beginning of the study, 177 patients had PBC stage I/II. During the observation period of ten years, ten patients died and in 18 orthotopic liver transplantation (OLT) was performed; all these patients belonged to profile C/D. Furthermore, 44% of the patients with profile C and 31% of the patients with profile D progressed to late stages, as defined by histology and clinical manifestations such as portal hypertension and increase of bilirubin, while only one of the patients with profile B and none of the profile A-patients developed late stage PBC. A significant increase of bilirubin was observed only in C/D-patients. AMA profiles did not change during the follow-up. In conclusion, AMA profiles discriminate between a benign and a progressive course of PBC already at early stages. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Significance of antibodies to soluble liver/liver pancreas antigen," published in a previous issue of the journal.

Apheresis has been effective as rescue therapy in patients with severe, therapy-resistant, systemic lupus erythematosus (SLE). Its benefit in patients with less severe but therapy-resistant SLE is not known. Dextran sulfate apheresis was applied as a rescue therapy for therapy-resistant vasculitic skin lesions in a 30 year old female patient with a 9 year history of SLE in combination with antiphospholipid syndrome and Raynaud's phenomenon. Partial remission was achieved after 9 immunoadsorption sessions, as documented by marked improvement of skin lesions and an increase of capillary density in the nailfold area. Further improvement was noted with maintenance therapy using mycophenolate mofetil. Dextran sulfate apheresis can be applied safely in patients with moderate therapy-resistant SLE disease activity when severe immunodeficiency and cytotoxic adverse effects should be avoided. [ABSTRACT FROM AUTHOR]

Background and Aims: Recently, a non-M2-related mitochondrial 60 kDa protein found to be recognized by antimitochondrial antibody (AMA) negative sera from patients with primary biliary cirrhosis (PBC) has been shown to contain parts of the five F(1)-ATPase subunits α, β, γ, δ and ε. In this study, we examined whether this enzyme is, indeed, a target antigen in PBC., Methods: Analysed were 60 AMA-positive/anti-M2-negative and 103 anti-M2-positive PBC patients, 46 patients with autoimmune hepatitis (AIH), 35 patients with primary sclerosing cholangitis (PSC), 110 patients with viral hepatitis, 40 patients with inflammatory bowel diseases (IBD), 33 patients with connective tissue diseases (systemic lupus erythematosus, mixed connective tissue disease, Sjögren disease, systemic sclerosis) and 25 blood donors. The F(1)-ATPase-subunits α-δ were recombinantly expressed in Escherichia coli, purified and applied to ELISA and Western blotting., Results: In all, 40 of the 60 AMA-positive/anti-M2-negative (67%) and 44 (43%) of the 103 anti-M2-positive PBC-sera reacted with at least one of the F(1)-subunits α-δ. The β- and γ-subunits were preferentially recognized. However, also up to 57% of patients with AIH and 34% of patients with PSC had anti-β- or γ-antibodies, while patients with viral hepatitis had these antibodies in up to 13%. Patients with IBD had anti-β and anti-γ-antibodies in up to 20 and 5% respectively. None of the patients with connective tissue diseases had antibodies to the β- and only 6% to the γ-subunit. Sera from healthy blood donors were negative., Conclusions: Antibodies to the β- and γ-subunits of F(1)-ATPase are further AMAs in PBC but occur also in other autoimmune liver disorders; they may be, therefore, indicators for a general autoimmune process of the liver., (© 2011 John Wiley & Sons A/S.)