[A 79-year-old man with B symptoms and jaw claudication]. / B-Symptomatik und Kauclaudicatio bei einem 79-jährigen Patienten.

A 79-year-old patient presented with weight loss, subfebrile body temperature and unclear jaw pain. After ruling out malignant and infectious causes, positron emission tomography-computed tomography (PET-CT) revealed markedly elevated glucose utilization of the large thoracic and upper limb arteries, suggesting systemic vasculitis. Color-coded duplex sonography confirmed thickening of the wall of the external carotid artery consistent with vasculitis. The patient was diagnosed with giant cell arteritis involving the large thoracic arteries and the upper limb arteries but without involvement of the superficial temporal artery. Based on the involvement of the external carotid artery, the jaw pain could be classified as jaw claudication. Clinical and laboratory remission was achieved with systemic glucocorticoids which could subsequently be tapered. The patient is well and asymptomatic 12 months after diagnosis and 2 months without steroids.

Characterization of the humoral immune response to Chlamydia outer membrane protein 2 in chlamydial infection.

Detection of antibodies to an outer membrane protein 2 (OMP2) by enzyme-linked immunosorbent assay (ELISA) by using either the Chlamydia trachomatis- or the Chlamydia pneumoniae-specific protein was investigated. OMP2 is an immunodominant antigen giving rise to antibody responses in humans infected with different C. trachomatis serovars (A to C and D to K) or with C. pneumoniae, which could be detected by OMP2 ELISA. OMP2 ELISA is not species specific, but antibody titers were usually higher on the homologous protein. The sensitivity of this assay was high but varied according to the "gold standard" applied. Levels of antibody to C. pneumoniae OMP2 as detected by ELISA seem to return to background or near-background values within a shorter period of time compared to antibodies to C. pneumoniae detected by microimmunofluorescence (MIF), making it more likely that positive results in ELISA reflect recent infection. Thus, OMP2 ELISA has distinct advantages over MIF and commercially available ELISAs and might be a useful tool for the serodiagnosis of chlamydial infection.

Antiendothelial antibodies in sera of patients with infective endocarditis.

Infective endocarditis is characterized by the colonization of endocardium by microorganisms. Except for Staphylococcus aureus, microorganisms are not able to adhere to and grow on endocardial cells; prior damage, e.g., by shear stress or other mechanical factors, is necessary. But other causes may well have a share. This study was, therefore, designed to identify immunological factors, especially antibodies against endothelial cells, which could contribute to the initiation of endocardial injury. Sera of patients with infective endocarditis and healthy controls were investigated for the presence of antibodies against endothelial antigen. As the antigen source human umbilical vein endothelial cells were used. Antibodies against endothelial cells were detected by indirect immunofluorescence, ELISA, immunoblotting, antibody dependent cellular cytotoxicity, and antibody mediated cytotoxicity. Antibodies against endothelial cells were found in seven out of fifteen patients. These antibodies were directed against cytoplasmic structures and only appeared in the course of the disease. A correlation between the presence of these antibodies and disease activity or the outcome of disease was not observed. These antibodies may develop as a consequence of damage to endocardial cells (thereby exposing intracellular antigen to the immune system) and do not seem to play a role in the pathogenesis of infective endocarditis.

[Eosinophilic myocarditis in Churg-Strauss syndrome. A rare cause of left heart decompensation with lung edema]. / Eosinophile Myokarditis bei Churg-Strauss-Syndrom. Seltene Ursache einer Linksherzdekompensation mit Lungenödem.

HISTORY: A 50-year-old woman was admitted because of marked dyspnoea at rest and signs of left heart failure with pulmonary oedema. 9 years ago, the diagnostic constellation of bronchial asthma, polyneuropathy, pericardial effusion and eosinophilia had indicated Churg-Strauss syndrome. Since then she had remained symptom-free under maintenance doses of azathioprine (for 2 years) and gradually reduced doses of steroids. INVESTIGATIONS: Chest X-ray showed signs of pulmonary congestion and cardiomegaly, echocardiography demonstrating enlargement of the left heart with marked impairment of ventricular function, and both revealed pericardial effusion. The electrocardiogram showed complete absence of R waves and ST elevation in leads V1-V5. Coronary angiography excluded coronary artery disease. Myocardial biopsy contained signs of active but no longer acute myocarditis with eosinophilic tissue infiltration and microgranulomas. White blood cell count was normal, but there was marked eosinophilia (39%). IgE was elevated (601 kIU/l). DIAGNOSIS, TREATMENT AND COURSE: In view of the good therapeutic effects 9 years ago, this relapse of Churg-Strauss syndrome with eosinophilic myocarditis was again treated with azathioprine and steroids. In addition, diuretics, digitalis and ACE-inhibitors successfully treated the heart failure. In the course of treatment the signs of inflammation, including the eosinophilia, regressed or became normal. CONCLUSION: After a 10-year remission without complication of a Churg-Strauss syndrome the onset of cardiac signs is the decisive long-term prognostic factor.

T lymphocyte lines isolated from atheromatous plaque contain cells capable of responding to Chlamydia antigens.

Chlamydia pneumoniae infection is associated with atherosclerosis and the organism has been identified in arterial lesions. To determine whether T lymphocyte-mediated immune responses to Chlamydia antigens within plaque could contribute to pathogenesis, we have derived T cell lines from atherosclerotic plaques of 32 patients. Culture with IL-2 alone proved insufficient for cellular activation and expansion, but additional stimulation with phytohaemagglutinin (PHA) or recall antigens allowed consistent establishment of T cell lines. Furthermore, in cultures of approx. 500 tissue fragments, Chlamydia organisms proved as effective as other recall antigens in producing outgrowth of arterial T cells (20-25% wells produced T cell lines). Testing the antigen responsiveness of T cell lines showed that those derived using Chlamydia organisms were more likely to respond to Chlamydia (5/29+) than those isolated using other stimuli (6/69+ for PHA; 5/57+ for PPD and tetanus toxoid (TT)). However, lines responsive to each of the recall antigens were observed. Using recombinant Chlamydia antigens, some Chlamydia-specific T cell lines were shown to respond to OMP2 and/or hsp60. Those recognizing Chlamydia hsp60 did not cross-react with human hsp60, but human hsp60-responsive lines were also observed. Thus, atherosclerotic plaque tissue contains a variety of memory T lymphocytes, and amongst these are cells capable of recognizing Chlamydia antigens. In a C. pneumoniae-infected plaque, such T cells may be activated by local antigen and could contribute to the inflammatory process in the arterial wall through CD40 ligand expression and cytokine secretion.

Definition of inflammatory cardiomyopathy (myocarditis): on the way to consensus. A status report.

This article reviews the current state of consensus reached for the diagnosis of myocarditis and dilated cardiomyopathy on the basis of conventional histopathological and immunohistochemical methods for inflammatory infiltrates in addition to molecular biological methods for persistence of viral genome in endomyocardial biopsies. Additionally, a brief overview is presented stating the current knowledge on effector mechanisms of the immune system in myocarditis and dilated cardiomyopathy.

Prevalence of viral genome in endomyocardial biopsies from patients with inflammatory heart muscle disease.

In the report of the 1995 World Health Federation/International Society and Federation of Cardiology (WHF/ISFC) Task Force on the Definition and Classification of Cardiomyopathies, the definition of heart muscle diseases was updated. Idiopathic, autoimmune, and infectious forms of inflammatory cardiomyopathy are now recognized in this definition. Enteroviruses, adenoviruses and cytomegaloviruses are considered as main etiopathological factors in the pathogenesis of inflammatory heart disease. A wide range of different assays have been and are currently being used, either alone or in combination, to assay for the presence of enteroviral RNA and/or DNA of cytomegalo- and adenoviruses in endomyocardial biopsy and explanted heart samples. The prevalence of cardiotropic viruses in endomyocardial biopsies of patients with clinically suspected inflammatory cardiomyopathy varies widely: enteroviral genome was detected in endomyocardial biopsies of 3 to 53% of patients, cytomegaloviral DNA was detected in 3 to 40% of patients with inflammatory heart disease and adenoviruses in 3 to 23% of the patients. This report summarizes the methods that have been used and the results of molecular biological investigation with polymerase chain reaction, which were reported by several groups over the last years. Taking this together it seems to be clear that the improvement of molecular biological techniques and the experience of people working with these methods will lead to more reliable results on prevalence, persistence and the diagnostic value of these investigations. These findings have to be taken into account in future diagnostic and therapeutic studies in the field of cardiomyopathies.

Immune responses to Chlamydia antigens in atherosclerosis.

Aim of this study was to isolate T lymphocytes from atheromatous plaques and to determine they respond to Chlamydia antigens. Atheromatous plaques from carotid endarterectomy patients, were cultured in vitro with the T cell growth factor, IL-2. This rarely allowed outgrowth of T cell lines. However, when combined with a mitogenic or antigenic stimulus to T cells, T cell lines were obtained from most patients, and from approximately 30% of replicate plaque tissue fragments. Chlamydia organisms were as effective in allowing the establishment of T cell lines as other recall antigens. T cell lines were tested for their ability to recognize antigens presented by autologous macrophages. Some lines responded to Chlamydia organisms, and also to the recombinant Chlamydia proteins hsp60 and OMP2. However, other lines recognized recall antigens. These results indicate that the atheromatous plaque contains memory T lymphocytes, and amongst the antigens they recognize are Chlamydia proteins. Stimulation of T cells was required to allow outgrowth in vitro, suggesting that the T cells were not in an activated state in vivo. However, since Chlamydia pneumoniae is present in the atheromatous plaque, activation of Chlamydia-reactive T cells by local antigen is a potential pro-inflammatory mechanism which could contribute to the pathogenesis of atherosclerosis.

Cytokine activation in pericardial fluids in different forms of pericarditis.

There are many causes of pericardial effusion and it is useful to classify them etiologically, since this disorder is the most common pathologic process involving the pericardium. This report details our experience with pericardioscopy and epicardial biopsy in 101 patients with pericardial effusions in whom pericardioscopy was performed. By means of clinical data and polymerase chain reaction we tried to elucidate the etiology of the pericardial effusion which were classified as follows: we found 41 effusions to be induced by primary malignant tumors or tumors metastatic to the pericardium. Specific diagnosis of viral and bacterial pericarditis was established in 17 patients by examination of the pericardial effusion with PCR, where we found 3 patients positive for adenovirus, 5 patients positive for cytomegalovirus, 2 patients positive for enterovirus-RNA and 5 patients positive for borrelia Burgdorferi-DNA. Additionally, idiopathic effusions (lymphocytic and autoreactive) were seen in 35 patients. In summary immunological and molecular biology investigations seem to provide an additional tool in the diagnostic of pericardial effusion with unknown etiology. If we focus on the ELISA results, there is some evidence, that the demonstration [table: see text] of activation markers and soluble mediators of inflammation such as Il-6, Il-8 and IFN-gamma in pericardial effusion and the simultaneously lack of these mediators in sera of the patients first may be helpful in the discrimination of autoreactive and lymphocytic effusion. Second, this cytokine pattern or distribution indicates a possible local inflammatory process, where these cytokines were all released from activated T lymphocytes present in lymphocytic effusion. In the future, this may have therapeutic implications.

[Cell death in inflammatory heart muscle diseases--apoptosis or necrosis?]. / Zelluntergang bei entzündlichen Herzmuskelerkrankungen--Apoptose oder Nekrose?

Cell death can be induced by 2 different mechanisms: necrosis and apoptosis. Necrosis, on the one hand, is usually caused by unphysiological stress factors such as hyperthermia or hypoxia, apoptosis, on the other hand, is part of the normal organ development and controls for example immune responses. Morphologically, necrosis is characterized by swelling of cells and their organelles leading to the disruption of the cell membrane, which in turn causes an inflammatory reaction in the surrounding tissue. Morphological and biochemical criteria (Figure 1, Table 1) of apoptosis are the condensation of chromatin leading to the development of apoptotic bodies or membrane-enclosed vesicles containing oligonucleosomal DNA fragments. Important diagnostic tools of cell death (Table 2), such as the TUNEL test (Figure 2) or gel electrophoresis of extracted DNA (Figure 3) are based on the above mentioned biochemical characteristics, but a reliable differentiation of apoptotic versus necrotic processes is not always possible. Experimental studies in animals and studies in various diseases of the cardiovascular system were able to show that apoptosis in myocytes can be induced, an issue that has long been discussed controversially. Ischemia, reperfusion, and myocardial infarction were also shown to lead to apoptosis in cardiomyocytes, whereas cell destruction was caused mainly by necrosis. Several authors (Table 3) demonstrated apoptotic indices in cardiomyocytes of patients with dilatated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy and patients with acute infarction from 0.25 to 35% by the use of the TUNEL test. Others were able to demonstrate an elevated expression of Fas-receptor in cells of atheroslerotic plaques in patients with atherosclerosis and high indices of apoptotic cardiomyocytes in patients with chronic heart failure. We investigated endomyocardial biopsies of patients with inflammatory cardiomyopathy, DCM without inflammatory reaction but the presence of adenoviral or cytomegaloviral genome and idiopathic DCM using the TUNEL test. The percentage of apoptotic cardiomyocytes in biopsies of patients with DCMi was 1.03 and in biopsies of patients with adenoviral genome 0.25, whereas in all other groups no apoptosis was found. If apoptosis plays a major role in myocardial diseases such as heart failure, arrhythmia and others, blocking this mechanism will have to be considered as a therapeutical strategy. Therefore, studies on the extent of apoptotic processes in diseased versus healthy cardiac tissue are of great importance.

Identification of mitochondrial antigens recognized by antibodies in sera of patients with idiopathic dilated cardiomyopathy by two-dimensional gel electrophoresis and protein sequencing.

Antimitochondrial antibodies in sera of patients with idiopathic dilated cardiomyopathy (IDC) have been described previously, but the corresponding antigens have not been analyzed systematically. We therefore used both 1-dimensional and high-resolution 2-dimensional gel electrophoresis followed by immunoblotting and N-terminal amino acid sequencing to identify the relevant mitochondrial antigens, which are recognized by serum antibodies. Sera were obtained from patients with IDC (n = 75) and healthy controls (n = 182). For detection of antimitochondrial antibodies the mitochondrial antigen fraction, consisting of submitochondrial particles isolated from a bovine heart, was separated on SDS-PAGE and all sera were examined by immunoblot analysis. For further characterization of the mitochondrial epitopes the antigen fraction was separated in the first dimension according to isoelectric points using isoelectric focusing followed by gel electrophoresis. Proteins recognized by serum antibodies in 2-dimensional immunoblots were analyzed by N-terminal amino acid sequencing. In 1-dimensional immunoblot analysis, 51% of patients with IDC and 34% of controls contained serum antibodies reacting with mitochondrial protein bands with molecular weights of about 30, 43, 60, and preferentially 50 to 55 and 70 to 75 kD (p <0.01). We identified a 75-kD subunit of nicotinamide-adenine dinucleotide dehydrogenase (17% in IDC patients vs 5% in controls, p <0.05) and 2 core proteins of ubiquinol-cytochrome-c reductase (core P1: 39% in IDC patients vs 15% in controls, p <0.05; core P2: 20% in IDC patients vs 10% in controls, p <0.1), both enzymes of the respiratory chain, as are most relevant mitochondrial antigens. Furthermore, serum antibodies of patients with IDC were directed against lipoamide-dehydrogenase (15% vs 10% in controls) and a subunit of pyruvate-dehydrogenase (9% vs 3% in controls). Because these antigens play an important role in energy metabolism, the respective antibodies can be more than merely diagnostic markers of cell damage. To attribute them also to pathogenetic relevance appears to be a most attractive but still speculative hypothesis.

Antibodies against stress proteins in sera of patients with dilated cardiomyopathy.

The pathogenesis of dilated cardiomyopathy (DCM) is as yet unknown. However, it is widely believed that autoimmune mechanisms contribute to the manifestations of the disease. In sera of patients with dilated cardiomyopathy, antibodies against different antigens, including heat shock protein (hsp) 60, were found. Antibodies against other stress proteins have not yet been reported. The aim of this study, therefore, was to screen sera of patients with DCM for the presence of antibodies against the major stress proteins. Lysate of stressed human endothelial cells was used as antigenic substrate in 1- and 2-dimensional immunoblot, since this cell type has recently been shown to express the major stress proteins. Antibodies against hsp60, hsp70, and heat shock cognate protein (hsc) 70 were detected in sera of patients with dilated cardiomyopathy as compared to healthy controls. Interestingly, antibodies against hsp70 and hsc70 were found in sera of patients younger than 30 years significantly more often than in older individuals. A correlation between the presence of antibodies against stress proteins and disease activity, clinical status, or histological findings was not detected. These findings support the view that DCM might be a consequence of an infectious disease, because stress proteins are immunodominant antigens in microbial agents and antibodies against stress proteins were detected in sera of patients with infectious diseases. Whether these antibodies are of pathogenetic significance or may be used as a disease marker will have to be elucidated in future experiments.

Autoantibodies in sera of patients with myocarditis: characterization of the corresponding proteins by isoelectric focusing and N-terminal sequence analysis.

In myocarditis an antigen-specific immune response to cardiac epitopes has been demonstrated by several investigators. In 54 patients with histologically proven myocarditis, autoantibodies to cardiac tissue were observed in 73% of patients utilizing the indirect immunofluorescence test with human myocardium and adult heterologous cardiocytes. By immunoblot, 44% of sera from patients reacted with cardiac tissue. These antibodies were directed preferentially against proteins with the molecular weight of 43 up to 67 kDa. Three particular proteins were identified by the use of two-dimensional immunoblot and further characterized by amino acid sequence analysis. To characterize the epitopes recognized by the autoantibodies isoelectric focusing followed by SDS-PAGE was used to separate the complex mixture of proteins from human heart. Immunoblot analysis of antigens revealed proteins ranging from a size of 30-67 kDa at isoelectric points of 6.5-8.5 to be of particular interest. Five of these proteins have now been analyzed by N-terminal amino acid sequencing (Edman degradation). One was found to be creatine kinase and one was identified as a yet unknown protein. Three proteins were N-terminally blocked and were investigated further by enzymatical digestion, followed by separation of the usually complex peptide mixtures on HPLC. One of the peptides was found to be dihydrolipoamide dehydrogenase, a membrane enzyme, and one was identified as a sarcomere specific creatine kinase. Because these proteins are intracullularly located enzymes, their pathogenetic role as antigens for the autoantibodies remains to be elucidated further.

Identification of stress proteins in endothelial cells.

Endothelial cells have been shown to play a major role in the pathophysiology of various diseases including ischemic heart disease and viral infection leading to myocarditis or dilated cardiomyopathy, conditions in which stress proteins (heat shock protein-hsp; glucose-related protein - grp) are likely to be involved. For further characterization of stress proteins and their possible role in these diseases, the major stress proteins in human endothelial cells were separated by two-dimensional polyacrylamide gel electrophoresis with immobilized pH gradients in the first dimension and identified by immunoblotting and either N-terminal or internal amino acid sequencing, respectively. Ubiquitin, hsp27, hsp60, hsp70, heat shock cognate protein 70, grp78 and grp75 were found to be constitutively expressed; hsp72 was found in stressed cells, exclusively, in line with results obtained in other human cell lines. Three additional proteins with molecular masses between 34 and 40 were regularly detected in stressed cells that were found to have identical amino acid sequences with those of members of the hsp70 family.