A new study shows that HHV-6A direct repeats can survive alone in an integrated state without the rest of the viral genome. The study also identified non-telomeric integration of HHV-6A in both in vitro cultured cells as well as one iciHHV-6A patient.
Neoplasia: could iciHHV-6A cause a benign HPV strain to turn deadly?
Human papillomavirus 4 is a benign strain not associated with cancer. However, in a woman with inherited chromosomally integrated HHV-6A, a high grade vaginal squamous lesion developed rapidly. The authors warn that there may be a synergistic effect between HPV4 and iciHHV6A.
HHV-6 U24 tightly linked to specific E3 ubiquitin ligases
The group that recently discovered a ligand for U24 has expanded upon their previous experiments to further elucidate the viral protein’s interactions and functions as they pertain to MS.
New mouse model for HHV-6 & 7
Investigators at Washington University have sequenced a murine herpesvirus and determined that it is closely related to HHV-6 & 7. Named Murine Rosesolovirus (MRV), the virus causes severe depletion of CD4+ T cells and thymic necrosis in young mice. The authors believe that MRV will be a useful mouse model to study the impact of HHV-6 & 7 in humans.
Opinion: call for ciHHV6 screening in transplantion
Two physicians from Texas propose that ciHHV6 status of donors and recipients be determined before solid organ transplantion, using a single pre-transplant qPCR test on whole blood, and that patients with ciHHV-6 or ciHHV-6 donors be carefully monitored for signs of active HHV-6 infection.
Multiple viral infections and HHV-6B increase risk of mortality in HSCT
A retrospective study of allogeneic hematopoietic stem cell transplant patients at University of Washington found that reactivation of several double stranded DNA viruses significantly increased the risk of overall mortality, as did an increased quantitative burden of viral exposure. HHV-6B conferred a significantly increased risk for overall mortality.
New data provides insight into how HHV-6A establishes persistent infections
A group led by Professor Niza Frenkel of Tel Aviv University in Israel has determined that HHV-6A limits its own replication to avoid detection and destruction, leading to a long life-cycle with limited propagation. This finding may reveal the mechanism behind persistent HHV-6A infections and help explain some disease associations.
Decreased HHV-6 IgG in Alzheimer’s
Investigators from Uppsala University in Sweden found that HHV-6 IgG reactivity was significantly lower in Alzheimer’s Disease patients compared to controls. The authors suggest reduced immunity may be one reason why past studies have found increased levels of HHV-6 DNA in the brains of Alzheimer’s patients compared to controls.
HHV-6 induced amnesia after rituximab therapy for autoimmune disease
A young woman on rituximab and two other immunomodulatory agents for the treatment of dermatomyositis developed encephalitis with severe anterograde amnesia. As the use of biologic treatments for refractory autoimmune disease has been increasing, physicians are advised to consider HHV-6 and offer prompt antiviral therapy to limit irreversible morbidity.
Does the high level of U94 in iciHHV-6 contribute to abnormal ‘marker’ chromosomes and cancer?
Investigators from the University of Ferrara, Italy have found evidence suggesting that high levels of U94 in ciHHV6 may predispose to the formation of marker chromosomes. A patient with diffuse large B-cell lymphoma positive for inherited chromosomally integrated HHV-6A and HHV-6A was also found in a marker chromosome, an abnormal piece of chromosome that is seen in some leukemia and lymphomas.
Anemia: Deformation of erythroblasts caused by HHV-6
A group from Japan has found that the deformation of erythroblasts seen in transient erythroblastopenia of childhood, is caused by HHV-6. Erythroblasts are progenitor cells in the bone marrow, necessary for the production of red blood cells.
New evidence linking HHV-6A U24 protein to MS
HHV-6 has been linked in numerous studies to multiple sclerosis. Now, investigators at the University of British Columbia have published new data suggesting that HHV-6A may be a key player in the development of multiple sclerosis. The investigators propose that the viral protein U24 may dysregulate myelination.
CD46 may function as a receptor for some strains of HHV-6B
A group from Aarhus University propose that differing isoform patterns of CD46 correlate with the ability of some HHV-6B strains to enter T cells.
HHV-6 encephalopathy associated with structural changes in the olfactory pathway
Latvian researchers studied autopsy material from the olfactory bulb in patients with HHV-6 encephalopathy vs. controls and reported surprising differences.
Possible inherited chromosomally integrated HHV-7 identified in two patients
Investigators led by Bhupesh Prusty, PhD at University of Wurzbürg in Germany have identified two cases of possible germline inherited chromosomally integrated HHV-7.