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SUMMARY Chromosomally integrated human herpesvirus 6 (ciHHV-6) is a condition in which the complete HHV-6 genome is integrated into the host germ line genome and is vertically transmitted in a Mendelian manner. The condition is found in less than 1% of controls in the USA and UK, but has been found at a somewhat higher prevalence in transplant recipients and other patient populations in several small studies. HHV-6 levels in whole blood that exceed 5.5 log10 copies/ml are strongly suggestive of ciHHV-6. Monitoring DNA load in plasma and serum is unreliable, both for identifying and for monitoring subjects with ciHHV-6 due to cell lysis and release of cellular DNA. High HHV-6 DNA loads associated with ciHHV-6 can lead to erroneous diagnosis of active infection. Transplant recipients with ciHHV-6 may be at increased risk for bacterial infection and graft rejection. ciHHV-6 can be induced to a state of active viral replication in vitro. It is not known whether ciHHV-6 individuals are put at clinical risk by the use of drugs that have been associated with HHV-6 reactivation in vivo or in vitro. Nonetheless, we urge careful observation when use of such drugs is indicated in individuals known to have ciHHV-6. Little is known about whether individuals with ciHHV-6 develop immune tolerance for viral proteins. Further research is needed to determine the role of ciHHV-6 in disease. Copyright © 2011 John Wiley & Sons, Ltd.

Aims Circulating adiponectin (APN) is an immunomodulatory, pro-angiogenic, and anti-apoptotic adipocytokine protecting against acute viral heart disease and preventing pathological remodelling after cardiac injury. The purpose of this study was to describe the regulation and effects of APN in patients with inflammatory cardiomyopathy (DCMi). Methods and results Adiponectin expression and outcome were assessed in 173 patients with DCMi, 30 patients with non-inflammatory DCM, and 30 controls. Mechanistic background of these findings was addressed in murine experimental autoimmune myocarditis (EAM), a model of human DCMi, and further elucidated in vitro . Adiponectin plasma concentrations were significantly higher in DCMi compared with DCM or controls, i.e. 6.8 ± 3.9 µg/mL vs. 5.4 ± 3.6 vs. 4.76 ± 2.5 µg/mL ( P < 0.05, respectively) and correlated significantly with cardiac mononuclear infiltrates (CD3+: r 2= 0.025, P = 0.038; CD45R0+: r 2= 0.058, P = 0.018). At follow-up, DCMi patients with high APN levels showed significantly increased left ventricular ejection fraction improvement, decreased left ventricular end-diastolic diameter, and reduced cardiac inflammatory infiltrates compared with patients with low APN levels. A multivariate linear regression analysis implicated APN as an independent prognostic factor for inhibition of cardiac inflammation. In accordance with these findings in human DCMi, EAM mice exhibited elevated plasma APN. Adiponectin gene transfer led to significant downregulation of key inflammatory mediators promoting disease. Mechanistically, APN acted as a negative regulator of T cells by reducing antigen specific expansion ( P < 0.01) and suppressed TNFα-mediated NFκB activation ( P < 0.01) as well as release of reactive oxygen species in cardiomyocytes. Conclusion Our results implicate that APN acts as endogenously upregulated anti-inflammatory cytokine confining cardiac inflammation and progression in DCMi.

Background Parvovirus B19 (B19V)-DNA is frequently detected in endomyocardial biopsies (EMBs) from patients with acute myocarditis (AMC) and dilated cardiomyopathy (DCM), but also in various healthy tissues. The clinical relevance of this DNA-persistence is unclear. Objectives To investigate potential pathogenic influences of B19V-DNA in EMBs, we analyzed B19V-specific adaptive immune responses in AMC/DCM patients and healthy controls. Study design 15 AMC/DCM patients with detectable B19V-DNA in EMBs and 51 controls were analyzed for signs of acute B19V-infections and virus-specific immune responses by PCR, ELISA, Western line, and ELISpot-assays. Results Productive B19V-infection was determined in three patients. Slightly lower levels of B19V-specific T-cells were observed in patients as compared to the controls, no differences were observed in virus-specific serology. Viral DNA-load in EMBs could not be correlated to the number of B19V-specific T-cells. No differences in T-cell response, viremia and/or serological markers indicative for viral pathogenesis were observed in patients with inflammatory cardiomyopathy. Conclusions Discrepancies in B19V-specific adaptive immunity were not observed in AMC/DCM patients as compared to controls. The data indicate that the exclusive detection of B19V-DNA in EMBs is not sufficient to associate B19V with AMC/DCM but should be complemented with additional virological and immunological parameters in further studies.

Human herpesvirus 6 (HHV-6) and HHV-7 are ubiquitous human pathogens with lymphotropic and neurotropic potential. Both viruses infect cells that express the CD46 complement receptor. Based on their biological properties and their receptor-dependent cellular tropism, HHV-6 and HHV-7 are detected in cells of different organs and consequently associated with various diseases. In addition to modulation of immune responses, HHV-6 and HHV-7 can directly infect endothelial cells and subsequently enter adjacent tissues. If the cardiovascular system is affected, HHV-6 and HHV-7 infections can be causative for myocarditis, vasospastic endothelial dysfunction, and development of post-infectious or post-inflammatory cardiomyopathies. Reactivation of HHV-6 is often associated with a higher percentage of chest pain, while inhibition of viral RNA is associated with clinical improvement of treated patients. This may be a therapeutic option for HHV-6-positive patients with unexplained cardiac symptoms.

A previously healthy 39-year-old man was admitted to our department with biventricular cardiac decompensation (New York Heart Association class IV) and acute onset of angina pectoris after a flulike disease 1 week earlier. The ECG on admission displayed ST elevations in II, III, and aVF. Troponin T on admission was increased (2.20 mg/L, normal value