A group from Hebrew University of Jerusalem has discovered the mechanism by cells with actively replicating HHV-6 evade elimination by natural killer (NK) cells.
Italian investigators found that 87% of patients with HHV-6 reactivations went on to develop a CMV infection. On the other hand, in patients who did not reactivate with HHV-6, only 33% developed an active CMV infection.
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 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.
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.
Instead of using the traditional epitope mapping approach to identify major targets of the T cell response to a complex pathogen, a group from the University of Massachusetts used mass spectrometry to identify viral proteins associated with immunodominant antigens.
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.
In an article published in the Pediatric Infectious Disease Journal, Tetsushi Yoshikawa’s team from Fujita Health University School of Medicine determined that the severe neutropenia in primary HHV-6B infection is tied to reduced platelet counts, lower RANTES and higher levels of MCP-1, MIG and IP-10.
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.