Chinese investigators found a high prevalence of HHV-6 and Epstein Barr virus in the brain tissues of children with Rasmussen’s encephalitis but in none of the controls. There was a significant association between viral presence and brain atrophy, raising a strong suspicion for the involvement of both viruses.
Swedish investigators have found HHV-6 protein in the pancreatic islet cells of both type 1 diabetes patients and controls. The viral load was higher in the islet cells than in surrounding tissues. Unfortunately, they did not provide data on the difference between patients and controls in the viral load.
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of psychotic symptoms) in response to three weeks of antiviral therapy but relapsed when antiviral therapy was withdrawn.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.