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A higher prevalence of inherited virus was found in patients
Investigators at Fred Hutchinson Cancer Center determined that transplant patients with inherited ciHHV-6 were twice as likely to develop acute graft vs host disease and three times more likely to develop high level CMV viremia. Transplant patients were also significantly more likely to have inherited ciHHV-6 than donors.
CD8+ T cells recover but CD4+ T cells remain low
Investigators in France discovered that monocytes and B lymphocytes recover quickly and become abnormally elevated by day 75 in cord blood patients, while they remain below normal or normal in stem cell patients. Although CD8 T cells recover, CD4+ T cells remain below normal levels for six months in both groups.
Italian investigators found that HHV-6 latency-associated gene U94, inserted in a HSV1 vector, inhibited the development of breast cancer, cervical cancer, and lung metastasis. It also impaired tumor driven angiogenesis.
Retrospective analysis of transplant patients revealed that low serum sodium levels are associated with HHV-6 encephalitis, but not HHV-6 myelitis. Low sodium is a possible marker for HHV-6 encephalitis post-transplantation.
A group led by Louis Flamand, PhD in Canada has developed a culture system that can be used to determine how the virus enters latency by integrating into the chromosome, and which drugs cause it to activate.
Growing evidence implicates HHV-6, especially HHV-6A, in some cases of female infertility, miscarriage, and other gestational problems affecting both the mother and child. The authors of the paper wonder if heparin, an anticoagulant with antiviral properties often used to treat infertility, might mitigate the detrimental effects of HHV-6 in the uterine environment.
Over a dozen studies have now found HHV-6 to predict aGVHD, but this is the first to correlate viral reactivation with poor CD4+ cell immune reconstitution.
Antibodies to HHV-6 and VZV dUTPases were significantly elevated in Gulf War Illness patients compared to controls, and EBV dUTPase antibodies were elevated in Chronic Fatigue Syndrome patients.
HHV-6B induces unique, region-specific DNA hypomethylation, and findings suggest that the epigenetic modification may facilitate HHV-6B integration.
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.
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.
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.
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.
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.
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.
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.
Japanese investigators from Kobe University identified CXC11 as a chemokine uniquely expressed in primary HHV-6B infections. They also confirmed a previous finding that cytokine CCL2 (MCP-1) plays a role in HHV-6B primary infections. Both CXCL11 and CCL2 are expressed in several neuroinflammatory conditions including epilepsy, Alzheimer’s disease and traumatic brain injury.
A group from Italy’s University of Bologna report that genetic defects in antimicrobial defense mechanisms can leave some individuals vulnerable to sub-clinical infections that lead to cognitive decline as they age. They found variations in specific antiviral genes that correlate with HHV-6 DNA levels in brain tissue and blood from patients with Alzheimer’s disease.
New data suggests HHV-6 and EBV are associated with the development of Alzheimer’s in elderly persons.
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.
Virologists led by Serge Barcy, PhD at the Seattle Children’s Research Institute and University of Washington have identified a homolog for HHV-7 in pigtail macaques They were surprised to learn that it could be detected in the peripheral nerve ganglia, and hope to use their new animal model to explore how HHV-7 might play a role in demyelinating diseases.
Seattle group announces the discovery of novel HHV-6 and HHV-7 homologs in pig-tailed macaques
New model of HHV-6A infection demonstrates persistent abortive infection and neuroinflammation via TLR9
Branka Horvat, MD, PhD, Director of Research at the International Centre for Infectiology Research in Lyon, France (INSERM), and her doctoral student Josephine Reynaud have recently published an important paper on a new transgenic mouse model
Could treatment of HHV-6A co-infections slow AIDS progression?
Dr. Steven Jacobson’s laboratory at the US National Institute of Health has developed a novel marmoset model for the study of HHV-6 infection.
Antibodies to HHV-6 and VZV dUTPases were significantly elevated in Gulf War Illness patients compared to controls, and EBV dUTPase antibodies were elevated in Chronic Fatigue Syndrome patients.
Investigators by at the University of Ferrara report intriguing alterations in intracellular regulation of HHV-6A-infected thyrocytes and T cells. HHV-6A, but not HHV-6B nor HHV-7, altered expression of several microRNAs in a pattern that is considered a marker for patients with autoimmune thyroid disease.
A fifth case of limbic encephalitis associated with GAD antibodies and HHV-6 infection has been reported, this time in an immunocompetent woman with chromosomally integrated HHV-6, epilepsy, and psychosis. The patient’s condition improved (with a drop in GAD antibody titers and stabilization of psychotic symptoms) in response to three weeks of antiviral therapy but relapsed when antiviral therapy was withdrawn.
Since both HHV-6 and EBV have been associated with an increased risk of autoimmune disease development, a group at the American University of Beirut studied whether viral DNA might be capable of triggering IL-17, a cytokine associated with autoimmune disease. They injected BALB/c mice intraperitoneally with either EBV or HHV-6A DNA. They found that both IL-17 and IL-23 were markedly elevated.
Researchers discuss the potential mechanisms by which HHV-6A/B may contribute to autoimmune disease
Case report describes two cases of DRESS related thyroiditis with very high levels of HHV-6 reactivation that go on to develop autoimmunity.
New study from Italy indicates that HHV-6 reactivation is selectively increased among patients suffering from autoimmune connective tissue diseases (ACTD).
A group from Italy has linked HHV-6A to Hashimoto’s Thyroiditis, and provides evidence for autoimmune disease associated with HHV-6A and HHV-6B.
Study finds high prevelence, high viral loads of HHV-6 in patients with Bell’s Palsy
A higher prevalence of inherited virus was found in patients
Investigators at Fred Hutchinson Cancer Center determined that transplant patients with inherited ciHHV-6 were twice as likely to develop acute graft vs host disease and three times more likely to develop high level CMV viremia. Transplant patients were also significantly more likely to have inherited ciHHV-6 than donors.
Italian investigators found that HHV-6 latency-associated gene U94, inserted in a HSV1 vector, inhibited the development of breast cancer, cervical cancer, and lung metastasis. It also impaired tumor driven angiogenesis.
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.
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.
Investigators at Yale University warn that hypersensitivity-associated HHV-6 lymphadenopathy can have the same presentation as lymphoma.
Biopsies from patients with 5 types of lymphoproliferative disorders of the ocular adnexa, were found to contain HHV-6 DNA in 9 of 70 (12.9%) samples. While an overall detection rate of 12.9% is significant, HHV-6 was even more prevalent among those with benign lymphoproliferative disorders; HHV-6 was found in 22.7% of those with IgG4-related ophthalmic disease and 28.6% of those with orbital reactive lymphoid hyperplasia.
A group from the National Institute of Neurological Disorders and Stroke, NIH, has reported finding Epstein-Barr Virus (EBV) and HHV-6 but no cytomegalovirus (CMV) in astrocytomas, a brain tumor comprising approximately one quarter of all gliomas diagnosed. The group used digital droplet PCR (ddPCR), a technique that is highly precise but less sensitive than nested PCR and immunohistochemistry, techniques that have been used in previous studies.
A recent study from investigators at Chongqing University in China explored the involvement of three viruses in the progression of pituitary adenomas (PA). The authors suggest that the HPV-16 and HHV-6 viruses activate the TLR3/ NF-kB signaling pathway which in turn contributes to the progression and proliferation of invasive pituitary adenomas.
Since the discovery of chromosomally integrated HHV-6 (ciHHV-6), investigators have wondered about the potential consequences of having chromosome integrated HHV-6 in the genome.
Scottish study finds inheritance of ciHHV-6 does not increase the risk of developing cHL
A group from Finland’s Helsinki University Hospital has published preliminary evidence to suggest HHV-6B may be involved in the development of adenomatous gastrointestinal polyps
A research team from Riga Stradins University in Latvia has reported that the activation of HHV-6B and HHV-7 in patients with gastrointestinal cancer may lead to a marked decrease in lymphocytes and worsening of immunosuppression.
Investigators from Nanjing Medical University have found HHV-6 latent infection in glioma tissues, and have isolated a strain of HHV-6A from the glioma cyst.
A thorough investigation of the association between HHV-6 and Hodgkin’s lymphoma finds the presence of HHV-6 in a majority of nodular sclerosis cases of HL.
Antibodies to HHV-6 and VZV dUTPases were significantly elevated in Gulf War Illness patients compared to controls, and EBV dUTPase antibodies were elevated in Chronic Fatigue Syndrome patients.
A prospective study authored by Joshua Hill and Danielle Zerr determined that higher than average HHV-6B DNA levels increased the odds of developing delirium after cord blood transplantation (CBT) by almost three fold. Patients with DNA loads in the top quartile had a 4.5 fold increase in delirium.
Stanford clinical trial indicates that VGCV may have a clinical benefit among a subset of CFS patients with HHV-6 and EBV infection
Researchers at the University Of South Florida’s Morsani College Of Medicine have published findings that suggest ciHHV-6 is the possible cause of some CFS cases
A new theory suggests CFS may be the result of a pathological infection of the vagus nerve.
A higher prevalence of inherited virus was found in patients
Investigators at Fred Hutchinson Cancer Center determined that transplant patients with inherited ciHHV-6 were twice as likely to develop acute graft vs host disease and three times more likely to develop high level CMV viremia. Transplant patients were also significantly more likely to have inherited ciHHV-6 than donors.
Most herpesviruses maintain latency by forming circular episomes in the nucleus of the cell. Investigators in Germany have provided further evidence that HHV-6A relies on their telomeres, not circular episomes, to maintain a persistent latent infection by integrating into the host chromosome.
A group led by Louis Flamand, PhD in Canada has developed a culture system that can be used to determine how the virus enters latency by integrating into the chromosome, and which drugs cause it to activate.
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.
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.
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.
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.
Investigators led by Bhupesh Prusty, PhD at University of Wurzbürg in Germany have identified two cases of possible germline inherited chromosomally integrated HHV-7.
A pregnant ciHHV-6B woman with a history of miscarriages was given weekly doses of high dose progesterone. Could progesterone, like hydrocortisone, activate integrated ciHHV-6 in vitro.
When the research team led by Benedikt Kaufer attempted to shed light on the mechanism behind HHV-6 integration, they were suprised to find telomeric repeats were critical to the integration process. Since the U94 gene shares homology and biological properties with the adenovirus Rep68 gene responsible for viral integration into human chromosomes, U94 was considered the most likely candidate to mediate HHV-6 integration.
A group led by Ursula Gompels from the London School of Hygiene & Tropical Medicine, University of London, did next generation sequencing on three ciHHV6A cardiac patients and found superinfections of HHV-6A in two of the three. They characterized the first full genome sequence of ciHHV-6A and demonstrated the inherited ciHHV6 genome was similar but distinct from known exogenous (community acquired) strains of HHV-6A .
In an article published this month in the Proceedings of the National Academy of Sciences, Dr. Louis Flamand’s team has described a relationship between inherited chromosomally integrated HHV-6 (iciHHV-6) and the development of angina pectoris.
Since the discovery of chromosomally integrated HHV-6 (ciHHV-6), investigators have wondered about the potential consequences of having chromosome integrated HHV-6 in the genome.
A sequencing study led by Ursula Gompels of London School of Hygiene & Tropical Medicine, found that 95% (19/21) of Czech ciHHV-6 malignancy and inflammatory disease patients had ciHHV6A while 65% (13/20) of a German myocarditis cohort had ciHHV-6B. The authors propose that this divergence suggests different disease links for the two viruses.
ciHHV-6 infants score 4 points lower than controls on the Bayley Mental Development Index
Antibodies to HHV-6 and VZV dUTPases were significantly elevated in Gulf War Illness patients compared to controls, and EBV dUTPase antibodies were elevated in Chronic Fatigue Syndrome patients.
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.
Three virologists led by Kazuhiro Kondo, MD, PhD, a professor of virology at Jikei University School of Medicine, have filed a patent on a method to diagnose and treat prevent mood disorders which he says are initiated by latent and neurovirulent HHV-6B residing in glial cells, and that this condition can be treated effectively with nasal sprays, using the olfactory nerve as a route to the brain. Dr. Kondo has named this protein SITH-1 or “small protein encoded by intermediate state transcript”.
A group of researchers from Sao Paulo, Brazil reported the development of HHV-6 infection in the striatum of a 32-year-old man six weeks after allogeneic hematopoietic stem cell transplantation. This is the first reported case of HHV-6 infection affecting the striatum and presenting with Parkinsonism post-HSCT.
A prospective study authored by Joshua Hill and Danielle Zerr determined that higher than average HHV-6B DNA levels increased the odds of developing delirium after cord blood transplantation (CBT) by almost three fold. Patients with DNA loads in the top quartile had a 4.5 fold increase in delirium.
HHV-6A and HHV-6B each express distinct chemokines that are uniquely capable of activating key inflammatory cytokines.
Unusually high rate of active HHV-6 infection detected among hospital patients with cardiac disease.
A Spanish study of drug-induced eosinophilia found that early hypogammaglobulinemia was associated with subsequent HHV-6 reactivation in patients with severe drug hypersensitivity syndromes. This study of 274 cases at La Paz University Hospital in Madrid confirms earlier reports from Japan and France that described transient reductions of total IgG at the outset of drug hypersensitivity reactions leading to HHV-6 reactivation.
It has long been a mystery why HHV-6 is preferentially reactivated in drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug induced hypersensitivity syndrome (DIHS). HHV-6 reactivation occurs in over 60% of severe cases and is part of the definition of DIHS in Japan. Investigators in Japan suspect that the explanation may lie with the CD134 receptor on activated CD4 cells.
A group from University of Chicago Medicine urged physicians to consider testing for HHV-6 in cases of unexplained liver failure in immunocompetent patients, especially those with skin rash and upper respiratory symptoms, citing evidence from past studies as well as their own recent case experience.
A new case study suggests that HHV-6 might play a role in the multi-organ failure that often follows extreme cases of drug hypersensitivity. Although there have been many studies documenting HHV-6 viremia in drug hypersensitivity (DIHS/DRESS) cases, this is the first to examine an affected organ for signs of HHV-6 DNA and proteins. The mortality rate from severe drug hypersensitivity is approximately 10%, and death usually results from a late flare in symptoms and failure of one or more organ, typically the liver, kidney, lungs or heart. HHV-6 viremia occurs in the majority of extreme drug hypersensitivity cases (Pritchett 2012) but the reason for the disproportionate reactivation of HHV-6 is not understood. The case, which is presented by a Japanese …
A group at the University of Pennsylvania performed a retroactive study of 29 pediatric patients hospitalized with drug hypersensitivity reactions and found that those who reactivated with HHV-6 had longer lengths of stay (11.5 days vs. 5. days) and more severe illness. They were not able to determine the impact of steroid administration in HHV-6 positive patients.
Drs. Ishida and Shiohara from Kyorin University in Tokyo have publised an inportant new study on the dynamics of herpesvirus reactivations during and after severe drug reactions. We asked them their thoughts on the implications of their findings.
In a recent study published in the European Journal of Allergy and Clinical Immunology, a group from Kyorin University School of Medicine in Tokyo sought to comprehensively record the dynamics of key herpesviruses beyond the acute stage of SJS/TEN. While EBV loads were higher in patients not receiving systemic corticosteroids, CMV and HHV-6 loads were higher in those receiving them.
A group of investigators in Japan have determined that HMGB-1, an inflammatory cytokine released in response to trauma, stress, and surgery, is highly elevated in DIHS/DRESS patients.
While elevated TNF-a detected at the early onset of disease is a strong indicator for the early recognition of HHV-6 reactivation, this finding also reflects important therapeutic information that could be used as an early diagnostic marker of DIHS/DRESS.
French panel of experts has proposed that DRESS patients be treated with antivirals and/or immunoglobulins.
Case report describes two cases of DRESS related thyroiditis with very high levels of HHV-6 reactivation that go on to develop autoimmunity.
A french group has found preliminary evidence that PCR saliva testing is useful for the detection of herpesvirus reactivation among patients with drug hypersensitivity syndromes.
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.
Latvian researchers studied autopsy material from the olfactory bulb in patients with HHV-6 encephalopathy vs. controls and reported surprising differences.
A new point-of-care assay from bioMérieux can simultaneously and rapidly detect 14 pathogens typically found in encephalitis. The machine is designed to be at the clinic or in the emergency room and can be operated by unskilled technicians. In a study of 1,560 immunocompetent patient samples, a total of 1.35% were positive for HHV-6, or about twice the expected rate of 0.8% found with the inherited chromosomally integrated HHV-6.
A fifth case of limbic encephalitis associated with GAD antibodies and HHV-6 infection has been reported, this time in an immunocompetent woman with chromosomally integrated HHV-6, epilepsy, and psychosis. The patient’s condition improved (with a drop in GAD antibody titers and stabilization of psychotic symptoms) in response to three weeks of antiviral therapy but relapsed when antiviral therapy was withdrawn.
Autopsy brain samples from 51 controls and 57 patients who died with encephalopathy of unknown origin were tested for HHV-6 & HHV-7 using immunohistochemistry, nested and real time PCR.
A prospective study authored by Joshua Hill and Danielle Zerr determined that higher than average HHV-6B DNA levels increased the odds of developing delirium after cord blood transplantation (CBT) by almost three fold. Patients with DNA loads in the top quartile had a 4.5 fold increase in delirium.
Two new reviews conclude that HHV-6 acute necrotizing encephalopathy is tied to a mutation of the RANBP2 gene.
Tehran University of Medical Sciences reports HHV-6 DNA in cerebrospinal fluid (CSF) samples of 8.8% of 114 infants suspected of encephalitis.
Experts emphasize need for larger studies to determine the impact of ciHHV-6 on patient outcomes
Edaravone shows promise for reducing oxidation and neuronal damage in AESD.
Should physicians automatically discount HHV-6 if any other pathogen is found in the CSF? Should patients with both HHV-6 and EBV DNA in the CSF be treated only for EBV? These are the questions that UW group tried to sort out in this study.
A group from Japan has conducted a retrospective study of 130 patients who underwent stem cell transplantation in an attempt to identify a risk factor for the development of encephalopathy.
HHV-6 encephalitis as a trigger in children with POLG mitochondrial disorders? Two cases of fatal Alpers-Huttenlocher syndrome
Japanese group identifies several cytokine and chemokine responses associated with HHV-6B encephalopathy.
Case report describes child with multiple episodes of febrile status epilepticus, followed by chorea and developmental regression, caused by human herpes virus-6 encephalitis.
HHV-6B induces unique, region-specific DNA hypomethylation, and findings suggest that the epigenetic modification may facilitate HHV-6B integration.
Australian investigators studied 143 young children with febrile seizures for signs of viral infection and found that HHV-6 was the fifth most common virus after rhinovirus (22%), enterovirus (20%), adenovirus (21%) and influenza (13%). Overall, a virus was found in 71% of cases. Virus found in complex seizures was associated with HHV-6 (42%) or influenza (41%).
A fifth case of limbic encephalitis associated with GAD antibodies and HHV-6 infection has been reported, this time in an immunocompetent woman with chromosomally integrated HHV-6, epilepsy, and psychosis. The patient’s condition improved (with a drop in GAD antibody titers and stabilization of psychotic symptoms) in response to three weeks of antiviral therapy but relapsed when antiviral therapy was withdrawn.
Japanese investigators published findings suggesting that HHV-6B plays a pathogenic role in epilepsy by enhancing gene expression that induces neuroinflammation and sclerosis in the temporal lobe. HHV-6 DNA levels were significantly higher in the resected tissue of epilepsy patients with sclerosis compared to those without it.
Tetsushi Yoshikawa and Yoshiki Kawamura just published an important study linking HHV-6B in brain tissues to sclerosis in mesial temporal lobe epilepsy. We asked him about this future plans and whether he plans to treat these patients.
A team of Chinese investigators led by Dr. Jin-Mei Li at West China Hospital has identified a possible synergy between a polymorphism of Apolipoprotein E (ApoE) and HHV-6B infection, resulting in a higher viral load and seizure frequency in these patients.
Investigators at the University of Bonn Medical Center in Germany have screened 346 fresh-frozen brain tissue resections from temporal lobe epilepsy (TLE) patients for all nine herpesviruses as well as for RNA viruses including Paramyxovirinae, Phleboviruses, Enteroviruses, and Flavivirus, using qPCR. HHV-6B was the only virus identified.
Pitt Niehusmann has completed the largest study to date on the question of whether viruses play a role in refractory mesial temporal lobe epilepsy (MTLE), with 346 samples analyzed. We asked Pitt a few questions about his work.
Immunocompetent adults are not supposed to get HHV-6 encephalitis or status epilepticus (SE) and HHV-6 testing is rarely performed in these patients. A new case report from Baylor suggests that testing for HHV-6 in these patients may be worthwhile.
A report published by a group from the University of Minnesota details the case of a 59-year-old male who developed non-convulsive status epilepticus and hyponatremia in addition to HHV-6 reactivation following umbilical cord blood transplantation.
Case report describes child with multiple episodes of febrile status epilepticus, followed by chorea and developmental regression, caused by human herpes virus-6 encephalitis.
A group from Spain has confirmed the existence of a novel epilepsy syndrome featuring generalized seizures and epileptic encephalopathy after HHV-6-associated PALE (posttransplant limbic encephalitis) in children.
A ten-year NIH-funded study has determined that a third of infants with prolonged seizures and fever suffer from either a new or reactivated roseola virus infection.
A group from the Royal Children’s Hospital in Melbourne, Australia has reported the development of epilepsy after HHV-6 posttransplant limbic encephalitis (PALE) among children receiving stem cell transplantation with cord blood (CBT).
Research groups in China, Germany and the US each publish compelling evidence that HHV-6 plays a role in epilepsy.
A comprehensive review of HHV-6 has been published in the American Society for Microbiology’s Clinical Microbiology Reviews.
Three important tests for HHV-6 will now be available at Coppe Labs, including two that are not available commercially at any other location: the mRNA test for assessing active infection and immunohistochemistry analysis for biopsy samples.
A higher prevalence of inherited virus was found in patients
Investigators at Fred Hutchinson Cancer Center determined that transplant patients with inherited ciHHV-6 were twice as likely to develop acute graft vs host disease and three times more likely to develop high level CMV viremia. Transplant patients were also significantly more likely to have inherited ciHHV-6 than donors.
HHV-6 may be the cause of “fever of unknown origin” in 30% of stem cell transplant (SCT) patients. By the third week after SCT, 70% of HHV-6 positive patients had a skin rash, compared to 39% of HHV-6 negative patients.
A group from Sapporo Medical University studied 105 post HSCT patients and determined that 7 developed CNS dysfunction in the first 42 days after transplant. Six out of the 7 were positive for HHV-6, but none of the other 12 pathogens tested. Four or 3.8% of the population were diagnosed with HHV-6 encephalitis.
A large-scale multiplex PCR assay developed by a team in Japan was used to study 13 DNA viruses in 105 allogenic hematopoietic stem cell transplant patients. They found that patients treated with steroids had a significantly higher risk of HHV-6 reactivation (p=0.027), and that HHV-6 was the only virus tied to the onset of acute GVHD (p=0.016).
HHV-6 reactivation before engraftment strongly predictive of graft failure
A group from Tokyo Medical University has determined that low level HHV-6 reactivation, but not CMV, EBV or HHV-7 reactivation, is a predictive marker for the development of grade 2-4 acute GVHD after hematopoietic stem cell transplantation (HSCT).
Study links HHV-6 reactivation to increasingly poor outcome following myeloablative HSCT
HHV-6 detection associated with increasingly poor outcome for stem cell transplant patients.
A group led by Ursula Gompels from the London School of Hygiene & Tropical Medicine, University of London, did next generation sequencing on three ciHHV6A cardiac patients and found superinfections of HHV-6A in two of the three. They characterized the first full genome sequence of ciHHV-6A and demonstrated the inherited ciHHV6 genome was similar but distinct from known exogenous (community acquired) strains of HHV-6A .
A case report published by a group at the University of Minnesota details two cases of fatal myocarditis associated with HHV-6 in two immunosuppressed children.
Researchers from Stanford University successfully used circulating cell-free DNA to identify infections in lung transplants that can often be found only with a more invasive transbronchial biopsy. This hypothesis free approach led to find HHV-6 & 7 at high levels in patients with infections, even though these viruses are not generally considered lung pathogens.
A hematology group in Australia reported a case of biopsy-proven HHV-6 myocarditis post-hematopoietic stem cell transplantation (HSCT). he post-mortem exam confirmed dilated cardiomyopathy and focal changes consistent with viral myocarditis and cardiac tissue was positive for HHV-6 DNA by nested and quantitative PCR. Separately, A Japanese group reported a worman who developed pericarditis with over 10,000 copies/ml of HHV-6 DNA in the pericardial fluid, after a cord blood transplant.
80% of infants with myocarditis were positive for a cardiotropic virus compared to less than 4% of healthy controls, according to a multicenter study led by researchers at Washington University in St. Louis. This was a far higher rate than in older children.
In an article published this month in the Proceedings of the National Academy of Sciences, Dr. Louis Flamand’s team has described a relationship between inherited chromosomally integrated HHV-6 (iciHHV-6) and the development of angina pectoris.
Numerous case reports and studies have now tied HHV-6 to myocarditis and cardiomyopathies. To further investigate this relationship, investigators from one of the top cardiology clinics in Europe performed a study to determine the outcome of patients discovered to have HHV-6 in their cardiac tissue during the initial biopsy screen.
A sequencing study led by Ursula Gompels of London School of Hygiene & Tropical Medicine, found that 95% (19/21) of Czech ciHHV-6 malignancy and inflammatory disease patients had ciHHV6A while 65% (13/20) of a German myocarditis cohort had ciHHV-6B. The authors propose that this divergence suggests different disease links for the two viruses.
Berlin Charite study shows heart failure patients with active ciHHV-6 can be treated successfully with antivirals.
The cardiology clinic at the Campus Benjamin Franklin, Charité – University Medicine Berlin is recognized as leading center for using state-of-the art mRNA analysis to diagnose active infections the biopsy tissue of myocarditis and heart failure patients.
Group suggests cardiac magnetic resonance (CMR) may be an important tool for the timely diagnosis
A group from Children’s Heart Centre in Lund, Sweden, has used Artesunate as an effective antiviral therapy to aid in the treatment of a child with HHV-6B myocarditis.
Unusually high rate of active HHV-6 infection detected among hospital patients with cardiac disease.
A group of physicians from the University Hospital in Reims, France, have reported a case of fatal HHV-6 myocarditis in an immunocompetent patient previously thought to be negative for HHV-6 infection.
A group from Sapienza University in Rome has found a significantly elevated prevalence of HHV-6 and a higher viral load for EBV in the stomach and duodenum biopsies of patients with HIV compared to controls, suggesting that these viruses may contribute to the development of gastric cancer in immunocompromised patients.
HIV+ individuals with ciHHV-6 may experience lower severity HIV disease.
Growing evidence implicates HHV-6, especially HHV-6A, in some cases of female infertility, miscarriage, and other gestational problems affecting both the mother and child. The authors of the paper wonder if heparin, an anticoagulant with antiviral properties often used to treat infertility, might mitigate the detrimental effects of HHV-6 in the uterine environment.
A pregnant ciHHV-6B woman with a history of miscarriages was given weekly doses of high dose progesterone. Could progesterone, like hydrocortisone, activate integrated ciHHV-6 in vitro.
A new study reported that HHV-6A infects the lining of the uterus in 43% of women with unexplained infertility but cannot be found in uterine lining of fertile women. Furthermore, the cytokine and the natural killer cell profiles were very different in patients with the infection. HHV-6A was found only in uterine endothelial cells, and not in the blood.
Italian study finds 62% of women who developed PR early in their pregnancies miscarried
A group of researchers from Denmark have shown that HHV-6B binds specifically to the acrosome of sperm
A new case study suggests that HHV-6 might play a role in the multi-organ failure that often follows extreme cases of drug hypersensitivity. Although there have been many studies documenting HHV-6 viremia in drug hypersensitivity (DIHS/DRESS) cases, this is the first to examine an affected organ for signs of HHV-6 DNA and proteins. The mortality rate from severe drug hypersensitivity is approximately 10%, and death usually results from a late flare in symptoms and failure of one or more organ, typically the liver, kidney, lungs or heart. HHV-6 viremia occurs in the majority of extreme drug hypersensitivity cases (Pritchett 2012) but the reason for the disproportionate reactivation of HHV-6 is not understood. The case, which is presented by a Japanese …
A new study from Brazil indicates that active HHV-6 infection may play a role in patients with renal failure prior to transplantation.
Italian investigators found that HHV-6 latency-associated gene U94, inserted in a HSV1 vector, inhibited the development of breast cancer, cervical cancer, and lung metastasis. It also impaired tumor driven angiogenesis.
Antibodies to HHV-6 and VZV dUTPases were significantly elevated in Gulf War Illness patients compared to controls, and EBV dUTPase antibodies were elevated in Chronic Fatigue Syndrome patients.
HHV-6B induces unique, region-specific DNA hypomethylation, and findings suggest that the epigenetic modification may facilitate HHV-6B integration.
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.
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.
Investigators at Johns Hopkins have determined that emetine, an older drug used to treat dysentery as well as to induce vomiting, is also effective against cytomegalovirus (CMV/HHV-5). Not only was emetine effective at an extremely low dose, it demonstrated a synergistic effect when combined with ganciclovir in a mouse model of CMV infection and it worked at a much earlier stage of viral replication than the drugs currently in use.
Chinese investigators from Nanjing Medical University report that HHV-6A infection of astrocytes are associated with differences in gene expression that are also found in several CNS diseases including Alzheimer’s, glioma and multiple sclerosis. The investigators used gene ontology analysis to determine the biological processes, cellular components, and molecular functions of the differentially expressed genes and signalling pathways.
A group from the National Institute of Neurological Disorders and Stroke, NIH, has reported finding Epstein-Barr Virus (EBV) and HHV-6 but no cytomegalovirus (CMV) in astrocytomas, a brain tumor comprising approximately one quarter of all gliomas diagnosed. The group used digital droplet PCR (ddPCR), a technique that is highly precise but less sensitive than nested PCR and immunohistochemistry, techniques that have been used in previous studies.
When the research team led by Benedikt Kaufer attempted to shed light on the mechanism behind HHV-6 integration, they were suprised to find telomeric repeats were critical to the integration process. Since the U94 gene shares homology and biological properties with the adenovirus Rep68 gene responsible for viral integration into human chromosomes, U94 was considered the most likely candidate to mediate HHV-6 integration.
It has long been a mystery why HHV-6 is preferentially reactivated in drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug induced hypersensitivity syndrome (DIHS). HHV-6 reactivation occurs in over 60% of severe cases and is part of the definition of DIHS in Japan. Investigators in Japan suspect that the explanation may lie with the CD134 receptor on activated CD4 cells.
An Italian study on immunocompetent children with suspected CNS infections found HHV-6 and HHV-7 DNA in 4.2% and 4.8% of 304 cerebrospinal fluid (CSF) samples, respectively. Although once considered rare in the immunocompetent, recent studies with more sensitive methods have found HHV-6 in the CSF of 4-17% of immunocompetent children with seizures or suspected CNS infections.
A group led by Ursula Gompels from the London School of Hygiene & Tropical Medicine, University of London, did next generation sequencing on three ciHHV6A cardiac patients and found superinfections of HHV-6A in two of the three. They characterized the first full genome sequence of ciHHV-6A and demonstrated the inherited ciHHV6 genome was similar but distinct from known exogenous (community acquired) strains of HHV-6A .
HHV-6A infection of mesothelial cells causes HLA molecule modulation. This study demonstrates, for the first time, that human mesothelial cells are susceptible to HHV-6A infection. They also show that the virus causes modulated HLA expression on the cell surface, inducing the de novo expression of HLA class II and HLA-G
Congratulations to Joshua Hill, MD, Acting Instructor at the University of Washington and Research Associate at the Fred Hutchinson Cancer Research Center, who has won a K23 grant from the National Institute of Allergy and Infectious Diseases to study HHV-6 in lower respiratory tract disease and chromosomally integrated HHV-6 after stem cell transplantation (SCT).
Investigators led by Eain Murphy of Cleveland Clinic have identified a viral microRNA (miRNA) for HHV-6A, named miR-U86, that targets the HHV-6A intermediate early gene U86.
A group from Washington University used a bioinformatics system called VirusScan to analyze RNA-Seq data sets from 6,813 human tumors compared to those of adjacent normal tissue. Tumor samples representing 23 different forms of cancer were analyzed. HHV-6, EBV and CMV were found at significantly high levels in GI tract cancer tissue.
Another case of drug induced liver injury accompanied by HHV-6 reactivation has been reported in Japan, the second such case without exanthema to be described. An earlier case was reported last year (Fujita 2015). The authors suggest that drug-induced liver injury cases be investigated for HHV-6 reactivation when liver dysfunction begins several weeks after the initiation of a new drug typically associated with hypersensitivity syndromes.
A group from University of Chicago Medicine urged physicians to consider testing for HHV-6 in cases of unexplained liver failure in immunocompetent patients, especially those with skin rash and upper respiratory symptoms, citing evidence from past studies as well as their own recent case experience.
New article describes acute HHV-6B hepatitis in an HCT recipient and reviews the current literature
French study suggests HHV-6 is a pathological cause of confluent necrosis.
Researchers from the University of Hannover have found a significant association between HHV-6 and decreased graft survival in liver transplant patients.
A pivotal study, led by Michael Boeckh at the Fred Hutchinson Cancer Research Center, has determined that occult infections contribute to 57% of all cases of “idiopathic” pneumonia syndrome (IPS), a condition previously assumed to be non-infectious. HHV-6 was the dominant pathogen representing 29% of cases.
Study finds HHV-6 DNA in children with unexplained fever at significantly higher levels than in patients without fever
A new case report describes a case of HHV-6 acute lymphadenitis in an immunocompetent patient, and reviews several other case reports of this condition.
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.
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.
Japanese investigators from Kobe University identified CXC11 as a chemokine uniquely expressed in primary HHV-6B infections. They also confirmed a previous finding that cytokine CCL2 (MCP-1) plays a role in HHV-6B primary infections. Both CXCL11 and CCL2 are expressed in several neuroinflammatory conditions including epilepsy, Alzheimer’s disease and traumatic brain injury.
HHV-6A infection of mesothelial cells causes HLA molecule modulation. This study demonstrates, for the first time, that human mesothelial cells are susceptible to HHV-6A infection. They also show that the virus causes modulated HLA expression on the cell surface, inducing the de novo expression of HLA class II and HLA-G
Anti-HHV-6 IgG titer may be a useful prognostic factor in predicting relapsing-remitting MS clinical course
New study shows HHV-6 may induce demyelination through both B and T-cell reaction. HHV-6 oligoclonal bands were also found in cases of clinically isolated syndrome.
HHV-6A major capsid protein identified in CSF of MS patients: a case of molecular mimicry?
A new study from NIH/NINDS further strengthens the relationship between HHV-6, EBV, and multiple sclerosis.
Dr. Steven Jacobson’s laboratory at the US National Institute of Health has developed a novel marmoset model for the study of HHV-6 infection.
An increased prevalence of HHV-6 U94/REP antibodies found among Tunisian MS patients.
Strong evidence of a genetic link between HHV-6 active replication and poor IFN-B treatment response among multiple sclerosis patients
A new study shows that multiple sclerosis patients with HHV-6 have higher risk of relapse and poor response to IFN-beta treatment.
The trigger for neurological disease in a subset of patients with MS?
The administration of immune agents to patients (known as Interferon-Beta-1b, or IFN-beta, therapy) has been widely used in the treatment and maintenance of multiple sclerosis (MS). Additionally, it is known that the risk of MS exacerbation is much higher in patients with active HHV-6 infection than in patients with a latent infection of the virus (Lafuente 2006, 2007; Chapenko 2003). In this new study from Madrid, researchers examined the effectiveness of IFN-1b therapy in multiple sclerosis patients with active HHV-6 infection. By monitoring the HHV-6 DNA levels of MS patients undergoing IFN-beta therapy, investigators were able to find that patients with active HHV-6 infection had a higher risk of severe MS relapse and poor response to IFN-beta therapy than patients …
Investigators by at the University of Ferrara report intriguing alterations in intracellular regulation of HHV-6A-infected thyrocytes and T cells. HHV-6A, but not HHV-6B nor HHV-7, altered expression of several microRNAs in a pattern that is considered a marker for patients with autoimmune thyroid disease.
Investigators have found that HHV-6 DNA and mRNA are more prevalent in the autoimmune thyroiditis biopsies than in controls, according to investigators in Latvia. HHV-6 mRNA was found in 41% of the patient biopsies compared to 6% of controls.
Human herpesvirus-6 (HHV-6) has been associated with several autoimmune diseases. A recent study led by Rizzo and Caselli have found a possible link to Hashimoto’s Thyroiditis (HT). They report that HHV-6 infection correlated with higher levels of a particular type of NK cell associated with a potent release of cytokines.
HHV-6A infection of mesothelial cells causes HLA molecule modulation. This study demonstrates, for the first time, that human mesothelial cells are susceptible to HHV-6A infection. They also show that the virus causes modulated HLA expression on the cell surface, inducing the de novo expression of HLA class II and HLA-G
Case report describes two cases of DRESS related thyroiditis with very high levels of HHV-6 reactivation that go on to develop autoimmunity.
A group from Italy has linked HHV-6A to Hashimoto’s Thyroiditis, and provides evidence for autoimmune disease associated with HHV-6A and HHV-6B.
CD8+ T cells recover but CD4+ T cells remain low
Investigators in France discovered that monocytes and B lymphocytes recover quickly and become abnormally elevated by day 75 in cord blood patients, while they remain below normal or normal in stem cell patients. Although CD8 T cells recover, CD4+ T cells remain below normal levels for six months in both groups.
Retrospective analysis of transplant patients revealed that low serum sodium levels are associated with HHV-6 encephalitis, but not HHV-6 myelitis. Low sodium is a possible marker for HHV-6 encephalitis post-transplantation.
Over a dozen studies have now found HHV-6 to predict aGVHD, but this is the first to correlate viral reactivation with poor CD4+ cell immune reconstitution.
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.
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.
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.
Only 11% of HHV-6 reactivated patients with poor immune reconstitution survived compared to 63% in patients with higher levels of T cells (or over 200 CD3+ lymphocytes per microliter).
A retrospective analysis out of the Tokyo Metropolitan Cancer and Infectious Diseases Center reviewed 353 consecutive adult allogeneic hematopoietic stem cell transplant (allo-HSCT) cases and identified 17 cases of CNS infection post-transplant. As determined by PCR on cerebrospinal fluid, HHV-6 was found to be the causative agent in 6 cases, or 1.7% of all transplants.
A group from the University of Minnesota studied the T cells of umbilical cord blood transplant patients and found that CD4+ T lymphocytes co-expressing CD134 contained more than twice the level of HHV-6B than cells without CD134 expression. Surprisingly, almost 70% of the CD134 negative cells contained HHV-6.
It has long been a mystery why HHV-6 is preferentially reactivated in drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug induced hypersensitivity syndrome (DIHS). HHV-6 reactivation occurs in over 60% of severe cases and is part of the definition of DIHS in Japan. Investigators in Japan suspect that the explanation may lie with the CD134 receptor on activated CD4 cells.
Another case of drug induced liver injury accompanied by HHV-6 reactivation has been reported in Japan, the second such case without exanthema to be described. An earlier case was reported last year (Fujita 2015). The authors suggest that drug-induced liver injury cases be investigated for HHV-6 reactivation when liver dysfunction begins several weeks after the initiation of a new drug typically associated with hypersensitivity syndromes.
A group from Baylor College of Medicine reviewed the efficacy of treating viral infections in transplant patients with primary immunodeficiencies using their viral-specific T lymphocytes. A total of 36 patients were treated with these immunotherapy infusions before or after undergoing hematopoietic stem cell transplantation, and a complete or partial antiviral response were seen in 86% of patients with CMV, 76% of patients with EBV and all patients with adenovirus or HHV-6.
A new study suggests that HHV-6 and HHV-7 are important co-factors for the development of CMV infection post-transplant in allogeneic hematopoietic stem cell transplantation patients. Additionally, the presence of HHV-7 and CMV together may result in more severe infections than either virus alone.
In a French study of 366 adult allogenic hematopeietic stem cell transplantation (aHSCT) recipients CD8+ T cell recovery was significantly reduced in patients with HHV-6 reactivation. HHV-6 reactivation was also associated with reduced survival and increased infections of CMV and BKV.
Researchers from Stanford University successfully used circulating cell-free DNA to identify infections in lung transplants that can often be found only with a more invasive transbronchial biopsy. This hypothesis free approach led to find HHV-6 & 7 at high levels in patients with infections, even though these viruses are not generally considered lung pathogens.
A group from Baylor College of Medicine reviewed the efficacy of treating viral infections in transplant patients with primary immunodeficiencies using their viral-specific T lymphocytes. A total of 36 patients were treated with these immunotherapy infusions before or after undergoing hematopoietic stem cell transplantation, and a complete or partial antiviral response were seen in 86% of patients with CMV, 76% of patients with EBV and all patients with adenovirus or HHV-6.
Trial explores immunotherapy for opportunistic viruses in transplantation
A group from Baylor has further characterized the clinical HHV-6B immune response, and is using this new information to develop an enhanced adoptive T cell immunotherapy specific to HHV-6 for HSCT patients.
A novel technique has been developed for the treatment of several viral infections–including HHV-6–following HSCT.
Edaravone shows promise for reducing oxidation and neuronal damage in AESD.
A group from Children’s Heart Centre in Lund, Sweden, has used Artesunate as an effective antiviral therapy to aid in the treatment of a child with HHV-6B myocarditis.
Investigators at Johns Hopkins have determined that emetine, an older drug used to treat dysentery as well as to induce vomiting, is also effective against cytomegalovirus (CMV/HHV-5). Not only was emetine effective at an extremely low dose, it demonstrated a synergistic effect when combined with ganciclovir in a mouse model of CMV infection and it worked at a much earlier stage of viral replication than the drugs currently in use.
A group from the University Medical Center in the Netherlands has shown that new gene editing technology can be used to impair viral replication and clear latent herpesvirus infections. The group used a CRISPR-Cas system to target viral genetic elements that completely eliminated CMV and HSV1 replication. They were also able to clear latent EBV from transformed human tumor cells.
Chimerix “SUPPRESS” trial to be largest study ever conducted for treatment of HHV-6 infection
A set of novel compounds synthesized by Microbiotix, Inc. have shown increased activity against a broad spectrum of human herpesviruses, including HHV-6.
Data from a recent report may increasingly argue in favor of using the antiviral known as CMX001 for treatment of HHV-6 infection.
New findings suggest salivary HHV-6 levels may be a good biomarker of QOL in patients during the course of chemotherapy.
