P6450Plasminogen activator inhibitor type-1 (PAI-1) expression relates to the presence of myocardial inflammation in patients with nonischemic cardiomyopathy

Background

Plasminogen activator inhibitor type-1 (PAI-1) is an important inhibitor of the fibrinolytic pathway and an acute phase reactant in response to inflammatory cytokines, resulting in thrombosis, arteriosclerosis, and tissue fibrosis. It has been identified as a potential biomarker for coronary artery disease and metabolic syndrom. However, so far, nothing is known about its importance in nonischemic cardiomyopathy.

Aims

To analyzed PAI-1 expression in patients with different forms of cardiomyopathies and evaluate possible influence of PAI-1-dependent pathomechanisms in patients with intramyocardial inflammation.

Methods and results

In this study, endomyocardial biopsies (EMBs) from 309 patients (mean age 48.0±13.9 years) with different forms of cardiomyopathies were enrolled, including 123 patients with dilated cardiomyopathy (DCM) (mean LVEF 28.01±9.06%) and 186 patients with EMB-proven virus-negative inflammatory cardiomyopathy (DCMi) (mean LVEF 31.76±14.14%). 10 patients (mean LVEF 60.50±4.76%) without viral or inflammation in EMB served as controls. Hemodynamic parameters were measured by catheterization and echocardiography. EMBs were performed at first admission after exclusion of ischemic of valvular heart disease. In EMBs PAI-1 was assessed by immunohistology including digital imaging analysis. PAI-1 expression was significantly higher in patients with DCMi in contrast to DCM patients and controls (0.517±2.20 vs. 0.187±0.598 vs. 0.023±0.032% Area Fraction; p=0.0002). PAI-expression correlates significantly with lymphocytic infiltrates (for CD3 r=0.56, p<0.0001, and LFA-1 r=0.59, p<0.0001). This was found to be independent of hemodynamic parameters, and age.

Conclusion

Myocardial inflammation is associated with a significant increase in PAI-1 expression in DCMi independently of the hemodynamic conditions. This new pathophysiological axis could be a potiential therapeutic target in future treatment stategies in DCMi.

5035Comparative assessment of diagnostic algorithms of myocardial inflammation by endomyocardial biopsy and tissue mapping by CMR against high-sensitive troponin in viral myocarditis

Background

Myocarditis is defined by inflammatory involvement of the myocardium, either histologically by evidence of myocardial necrosis and cellular infiltration on endomyocardial biopsy (EMB), or non-invasively by presence of myocardial oedema using tissue mapping with cardiovascular magnetic resonance (CMR). Objective: to undertake intra-individual comparisons of EMB vs. CMR diagnostic algorithms of myocardial inflammation, as well as against an independent gold-standard of myocardial injury, high-sensitive troponin (hs-TropT).

Methods

Prospective multicentre study of consecutive patients (n=109) with clinical diagnosis of myocarditis. EMBs were analysed by 2 reference centres using the ESC diagnostic and their local algorithms. The CMR criteria used sequence-specific cut-offs for native T1 and T2 (standard deviation, SD); myocardial inflammation T1 ≥2SD, T2 ≥2SD and no inflammation: T1 and T2<2SD, with subcategories for acute/high-grade: T1 ≥5SD, T2 ≥2SD; chronic/low-grade: T1 ≥2SD, T2 ≥2SD; healed: T1 <2SD, T2 <2SD but myocardial impairment and non-inflammatory cardiomyopathy: T1 ≥2SD, T2 <2SD.

Results

The agreement between ESC criteria and CMR criteria (AUC: 0.56, p=0.381) was poor. There was a significant agreement between myocardial injury (hs-TropT ≥13.9 ng/L) and CMR criteria (AUC: 0.84, p<0.001), but not ESC algorithm. hs-TropT levels had significant associations with native T1 and T2 (r=0.37 and 0.35, p<0.001), but not with immunohistochemical inflammatory markers. Viral presence was similarly proportioned between inflammatory/non-inflammatory subjects, irrespective of the algorithm.

AUC of CMR and EMB versus hs-TroponinT

Conclusions

Poor agreement between CMR and EMB-based diagnostic algorithms suggests non-overlapping definitions of myocardial inflammatory involvement. Excellent agreement between CMR algorithm and hs-TropT reiterates its high sensitivity for inflammatory myocardial injury.

Acknowledgement/Funding

1. National Institute for Health Research (NIHR) Biomedical Research Centre 2. German Centre for Cardiovascular Research (DZHK)

Analyses of germline, chromosomally integrated human herpesvirus 6A and B genomes indicate emergent infection and new inflammatory mediators

Human herpesvirus-6A (HHV-6A) is rarer than HHV-6B in many infant populations. However, they are similarly prevalent as germline, chromosomally integrated genomes (ciHHV-6A/B). This integrated form affects 0.1-1 % of the human population, where potentially virus gene expression could be in every cell, although virus relationships and health effects are not clear. In a Czech/German patient cohort ciHHV-6A was more common and diverse than ciHHV-6B. Quantitative PCR, nucleotide sequencing and telomeric integration site amplification characterized ciHHV-6 in 44 German myocarditis/cardiomyopathy and Czech malignancy/inflammatory disease (MI) patients plus donors. Comparisons were made to sequences from global virus reference strains, and blood DNA from childhood-infections from Zambia (HHV-6A mainly) and Japan (HHV-6B). The MI cohort were 86 % (18/21) ciHHV-6A, the cardiac cohort 65 % (13/20) ciHHV-6B, suggesting different disease links. Reactivation was supported by findings of 1) recombination between ciHHV-6A and HHV-6B genes in 20 % (4/21) of the MI cohort; 2) expression in a patient subset, of early/late transcripts from the inflammatory mediator genes chemokine receptor U51 and chemokine U83, both identical to ciHHV-6A DNA sequences; and 3) superinfection shown by deep sequencing identifying minor virus-variants only in ciHHV-6A, which expressed transcripts, indicating virus infection reactivates latent ciHHV-6A. Half the MI cohort had more than two copies per cell, median 5.2, indicative of reactivation. Remarkably, the integrated genomes encoded the secreted-active form of virus chemokines, rare in virus from childhood-infections. This shows integrated virus genomes can contribute new human genes with links to inflammatory pathology and supports ciHHV-6A reactivation as a source for emergent infection.

[Quality analysis for treatment of heart muscle diseases]

Distinct examinations and resulting therapies are depending on the cardiomyopathy phenotype and the severity of the myocardial compromise. Specific treatment modalities for distinct cardiomyopathies, demand detailed diagnostic procedures in addition to the routine diagnostic workup. Quality analyses for causal treatment strategies of different cardiomyopathies are missing. Most diagnostic procedures are unable to detect the relevant pathophysiological changes that generally occur at the cellular and molecular level of myocardial tissue or individual cells. Therefore, often only additional biopsy-based tissue analyses can provide the necessary basis for causal treatment options.

Prevalence of erythrovirus genotypes in the myocardium of patients with dilated cardiomyopathy

Parvovirus B19 (PVB19) is a member of the human erythrovirus family detected frequently in endomyocardial biopsies from patients with dilated cardiomyopathy. Human erythroviruses cluster into three genotypes 1-3 which share a high degree of homology between major structural proteins and may cause indistinguishable infections clinically and serologically. In human cardiac tissue erythrovirus genotypes other than PVB19 have not yet been reported. Three hundred seventeen consecutive patients with symptomatic dilated cardiomyopathy (median left ventricular ejection fraction: 28.6%, range 5-45%) who underwent endomyocardial biopsy for the elucidation of the etiology, were analyzed using a new consensus PCR assay designed for the detection of the three erythrovirus genotype sequences. Endomyocardial biopsies of 151 (47.6%) patients were erythrovirus-positive. Genotype 1 specific sequences were detected in 43/151 (28.5%) of positive biopsy samples, whereas genotype 2-specific sequences so far considered rare in human disease and not yet been described in human heart tissue was identified in 108/151 (71.5%) of virus-positive endomyocardial biopsies with a preference in patients above 50 years of age. In spite of younger age, systolic left ventricular dysfunction of genotype 1-positive patients was significantly reduced as compared to genotype 2-positive patients (24.4+/-10.4% vs. 31.0+/-9.5%, P=0.0001) at the initial presentation. The data show that two genetically distinct erythrovirus variants with a different age distribution are detectable in endomyocardial biopsies of patients with dilated cardiomyopathy. The erythrovirus genotype 2, not described previously in human heart tissue, is highly prevalent in the heart but the less prevalent genotype 1 is associated with more severe disturbed cardiac function.

Genomic expression profiling of human inflammatory cardiomyopathy (DCMi) suggests novel therapeutic targets

The clinical phenotype of human dilated cardiomyopathy (DCM) encompasses a broad spectrum of etiologically distinct disorders. As targeting of etiology-related pathogenic pathways may be more efficient than current standard heart failure treatment, we obtained the genomic expression profile of a DCM subtype characterized by cardiac inflammation to identify possible new therapeutic targets in humans. In this inflammatory cardiomyopathy (DCMi), a distinctive cardiac expression pattern not described in any previous study of cardiac disorders was observed. Two significantly altered gene networks of particular interest and possible interdependence centered around the cysteine-rich angiogenic inducer 61 (CYR61) and adiponectin (APN) gene. CYR61 overexpression, as in human DCMi hearts in situ, was similarly induced by inflammatory cytokines in vascular endothelial cells in vitro. APN was strongly downregulated in DCMi hearts and completely abolished cytokine-dependent CYR61 induction in vitro. Dysbalance between the CYR61 and APN networks may play a pathogenic role in DCMi and contain novel therapeutic targets. Multiple immune cell-associated genes were also deregulated (e.g., chemokine ligand 14, interleukin-17D, nuclear factors of activated T cells). In contrast to previous investigations in patients with advanced or end-stage DCM where etiology-related pathomechanisms are overwhelmed by unspecific processes, the deregulations detected in this study occurred at a far less severe and most probably fully reversible disease stage.

Inflammation, ECG changes and pericardial effusion: whom to biopsy in suspected myocarditis?

The role of endomyocardial biopsies in patients with clinically suspected acute myocarditis, myocarditis in the past, and dilated cardiomyopathy is discussed controversially. In fact, it is still under discussion whether information obtained from endomyocardial biopsies is relevant for further clinical decisions. Therefore this Critical Perspective will deal with the question, which patient should undergo endomyocardial biopsy investigations for an etiopathogenic differentiation of the disease and for the possible choice of immunomodulatory treatment strategies.

[Cardiomyopathies. I: classification of cardiomyopathies--dilated cardiomyopathy]

Cardiomyopathies are common causes of heart failure and sudden cardiac death. According to the WHO classification, "specific" cardiomyopathies are differentiated from "idiopathic" cardiomyopathies. Thus, this classification is primarily based on pathophysiological characteristics. The diagnostic spectrum in cardiomyopathies comprises the entire spectrum of non-invasive and invasive cardiological examination techniques. The exact verification of certain cardiomyopathies necessitates additionally investigations. For example, immunohistological and molecular biological investigations of endomyocardial biopsies may confirm inflammatory cardiomyopathy, which is often induced by viruses. Several studies have shown that specific immunomodulatory treatment options can halt the progressive course of the disease. Several gene mutations have been identified in genetic/familial dilated cardiomyopathy. First-degree relatives should be screened for early stages. Primary prevention of sudden cardiac death shows increasing superiority of the implantable defibrillator compared with pharmacological approaches (i.e. amiodarone).

[Cardiomyopathies II. Hypertrophic cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy]

This review focuses on hypertrophic (HCM), restrictive (RCM) and arrhythmogenic right ventricular cardiomyopathies (ARVC). The clinical phenotype of HCM depends not only on the gene mutations involved, but also on "modifier genes". It is characterized by an asymmetrical hypertrophy. Investigations of endomyocardial biopsies (EMBs) typically reveal a disarray of the hypertrophied cardiomyocytes. Percutaneous septum ablation has gained relevance as the treatment of choice in hypertrophic obstructive cardiomyopathy. Myocardial and endomyocardial RCM-forms can be differentiated. Enlargement of the atria in concert with normal dimensions of the ventricles and almost normal systolic contractility as well as the dip-plateau phenomenon are characteristic findings in RCM. EMB diagnostics are pivotal to identify the causes underlying secondary RCM types. Treatment is directed at heart failure and specifically at the underlying disease. With ARVC, apoptosis, viral infection/inflammation and genetic dystrophy result in fibrofatty degeneration primarily of the right, and with further progression also of the left ventricle. The primary treatment goal in ARVC is prevention of sudden cardiac death. As for other cardiomyopathies, there is increasing evidence for the superiority of ICD compared with pharmacological approaches.

Diagnosis and monitoring of acute cytomegalovirus infection in peripheral blood of transplant recipients by nested reverse transcriptase polymerase chain reaction (RT-PCR)

The aim of this novel diagnostic approach is to monitor cytomegalovirus (CMV) infection in immunocompromised transplant recipients using early, sensitive, and specific predictors before and during antiviral therapy. The peripheral blood cells of 20 patients after transplantation (9 liver, 7 kidney, 4 simultaneous kidney-pancreas) were studied for an early diagnosis of acute infection. The mRNA and DNA of human CMV immediate-early antigen (IEA) were detected by nested-polymerase chain reaction (PCR) assay. Results of nested PCR were compared with the immunological detection of antigen pp65 and serological diagnosis of CMV infection. All data were correlated with clinical symptoms like leukopenia, thrombopenia, pneumonia, and allograft-rejection reaction. Of 20 transplant recipients, 12 were infected by CMV, and 9 suffered from a CMV-related disease. CMV mRNA were detected simultaneously with antigen pp65 and CMV DNA in all patients with symptomatic infection. Additionally, CMV mRNA was found over a longer period after ganciclovir treatment of infected recipients. Nested reverse transcriptase (RT)-PCR for CMV-IEA mRNA allows a sensitive and specific diagnosis of an acute CMV infection. CMV mRNA was found to be a good marker of acute viremia and could be a useful tool for CMV monitoring over the whole period of disease management, even during antiviral therapy.

Modulation of multidrug resistance in human leukemia cells with mdr1-targeted antisense oligonucleotides using variable treatment schedules

OBJECTIVE

The purpose of the current study was to characterize the effect of chimeric AS-ODNs encapsulated with cationic lipids on MDR in human leukemia cells and to determine if this modification of the ODN alone or in combination with the cationic lipid might offer advantages over classical ODN treatment with free unmodulated or phosphorothiolated AS-ODNs. Furthermore, we extended the antisense method to the use of AS-ODNs in the parental drug-sensitive leukemia cells which express mdr1-mRNA at a relative low level and lack P170 expression to evaluate the effectiveness of prophylactic AS-ODN treatment.

METHODS

The effect of a 4-day AS-ODN treatment in drug-resistant human leukemia cells which exhibit the classic MDR phenotype at a moderate level was examined. Twenty-four hours after the last ODN administration the cells were analyzed for mdr1-mRNA (quantitative RT-PCR) and P170 expression (FCM), for R123 accumulation/efflux capacity (FCM) and for sensitivity to vincristine (MTT). In the parental drug-sensitive CCRF-CEM cells the mdr1-mRNA expression was assessed 24, 48 and 72 h after AS-ODN treatment administered as free phosphorothioate or conjugated with DMRIE-C.

RESULTS

Cationic lipids produced a clear increase in cellular ODN uptake but also caused an increase in variability of uptake rates (30% vs. 10% variability after free phosphorothioates). Both AS-ODNs inhibit P170 expression whereby the antisense effect of the chimeric ODN seems to be stronger compared to the phosphorothioate (30% vs. 22% MRK16 staining). Consistent with the inhibition of P170 expression, an increased sensitivity to vincristine was observed. In parental drug-sensitive cells, AS-ODN treatment caused nearly complete inhibition of mdr1-mRNA expression (5% of control).

CONCLUSION

The data demonstrate that it is nearly impossible to achieve a complete reversal of the MDR phenotype in drug-resistant cells using AS-ODNs. A more promising approach seems to be the prophylactic treatment with AS-ODNs.

Absolute levels of MDR-1, MRP, and BCL-2 MRNA and tumor remission in acute leukemia

Mononuclear cells prepared from peripheral blood or bone marrow of 119 AML and 28 ALL patients prior and following therapy were analyzed for absolute transcript levels of the chemoresistance genes mdr-1 and MRP, and the proto-oncogene bcl-2, by validated contamination-protected quantitative RT-PCR. In newly diagnosed AML mainly tumors of the granulocytic lineage (FAB M1-M2) expressed increased mdr-1 mRNA amounts. The MRP gene was expressed in all investigated samples without relation to a particular FAB class. High initial expression of both genes did not confer a poor prognosis even at high number of CD34+ cells. Data compared prior to and after therapy start (paired samples) revealed that AML patients who did not respond to therapy (NR) expressed increased levels of mdr-1 mRNA, as well as MRP and bcl-2 cDNA normalized to GAPDH reference transcripts, when compared to patients achieving complete remission (CR; p = 0.003, 0.008 and 0.0005, respectively). In ALL-NR the mdr-1 and bcl-2 genes were entirely more active after induction chemotherapy. Arbitrary cut-off values were established in order to delimit pathological from non-pathological gene expression. 59% of studied AML and 33% of ALL-NR exceeded the arbitrary values (mdr-1: > 2 amol/microgram RNA, MRP: > 10 zmol/amol GAPDH, bcl-2: > 5 zmol/amol GAPDH) for one and 11% of AML-NR for two parameters. Only 17% of the AML-CR and none of the ALL-CR group were above these limits. The results indicate that high individual activity of usually one, rarely two of the investigated genes might be associated with poor clinical outcome in treated acute leukemia.