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Summary: Pattern recognition receptors (PRRs) induce host defense but can also induce exacerbated inflammatory responses. This raises the question of whether other mechanisms are also involved in early host defense. Using transcriptome analysis of disrupted transcripts in herpes simplex virus (HSV)-infected cells, we find that HSV infection disrupts the hypoxia-inducible factor (HIF) transcription network in neurons and epithelial cells. Importantly, HIF activation leads to control of HSV replication. Mechanistically, HIF activation induces autophagy, which is essential for antiviral activity. HSV-2 infection in vivo leads to hypoxia in CNS neurons, and mice with neuron-specific HIF1/2α deficiency exhibit elevated viral load and augmented PRR signaling and inflammatory gene expression in the CNS after HSV-2 infection. Data from human stem cell-derived neuron and microglia cultures show that HIF also exerts antiviral and inflammation-restricting activity in human CNS cells. Collectively, the HIF transcription factor system senses virus-induced hypoxic stress to induce cell-intrinsic antiviral responses and limit inflammation.

The mechanisms underlying susceptibility to recurrent herpes simplex virus type 2 (HSV-2) meningitis remain incompletely understood. In a patient experiencing multiple episodes of HSV-2 meningitis, we identified a monoallelic variant in the IKBKE gene, which encodes the IKKε kinase involved in induction of antiviral IFN genes. Patient cells displayed impaired induction of IFN-β1 (IFNB1) expression upon infection with HSV-2 or stimulation with double-stranded DNA (dsDNA) and failed to induce phosphorylation of STING, an activation marker of the DNA-sensing cyclic GMP-AMP synthase/stimulator of IFN genes (cGAS/STING) pathway. The patient allele encoded a truncated IKKε protein with loss of kinase activity and also capable of exerting dominant-negative activity. In stem cell–derived microglia, HSV-2–induced expression of IFNB1 was dependent on cGAS, TANK binding kinase 1 (TBK1), and IKBKE, but not TLR3, and supernatants from HSV-2–treated microglia exerted IKBKE-dependent type I IFN–mediated antiviral activity upon neurons. Reintroducing wild-type IKBKE into patient cells rescued IFNB1 induction following treatment with HSV-2 or dsDNA and restored antiviral activity. Collectively, we identify IKKε to be important for protection against HSV-2 meningitis and suggest a nonredundant role for the cGAS/STING pathway in human antiviral immunity.

Background: Radiotherapy of the prostate and the pelvic lymph nodes (LN) is a part of the standard of care treatment for high‐risk prostate cancer. The independent translational and rotational (i.e., six‐degrees‐of‐freedom, [6DoF]) motion of the prostate and LN target during and between fractions can perturb the dose distribution. However, no standard dose reconstruction method accounting for differential 6DoF target motion is available. Purpose: We present a framework for monitoring motion‐induced dose perturbations for two independently moving target volumes in 6DoF. The framework was used to determine the dose perturbation for the prostate and the LN target caused by differential 6DoF motion for a cohort of high‐risk prostate cancer patients. As a potential first step toward real‐time dose‐guided high‐risk prostate radiotherapy, we furthermore investigated if the dose reconstruction was fast enough for real‐time application for both targets. Methods: Twenty high‐risk prostate cancer patients were treated with 3‐arc volumetric modulated arc therapy (VMAT). Kilovoltage intrafraction monitoring (KIM) with triggered kilovoltage (kV) images acquired every 3 throughout 7–10 fractions per patient was used for retrospective 6DoF intrafraction prostate motion estimation. The 6DoF interfraction LN motion was determined from a pelvic bone match between the planning CT and a post‐treatment cone beam CT (CBCT). Using the retrospectively extracted motion, real‐time 6DoF motion‐including dose reconstruction was simulated using the in‐house developed software DoseTracker. A data stream with the 6DoF target positions and linac parameters was broadcasted at a 3‐Hz frequency to DoseTracker. In a continuous loop, DoseTracker calculated the target dose increments including the specified motion and, for comparison, without motion. The motion‐induced change in D99.5% for the prostate CTV (ΔD99.5%) and in D98% for the LN CTV (ΔD98%) was calculated using the final cumulative dose of each fraction and averaged over all imaged fractions. The real‐time reconstructed dose distribution of DoseTracker was benchmarked against a clinical treatment planning system (TPS) and it was investigated whether the calculation speed was fast enough to keep up with the incoming data stream. Results: Translational motion was largest in cranio‐caudal (CC) direction (prostate: [‐5.9, +8.4] mm; LN: [‐9.9; +11.0] mm) and anterior–posterior (AP) direction (prostate:[‐5.6; +6.9] mm; LN: [‐9.6; +11.0] mm). The pitch was the largest rotation (prostate: [‐22.5; +25.2] deg; LN: [‐3.9; +5.5] deg). The prostate CTV ΔD99.5% was [‐16.2; +2.5]% for single fractions and [‐3.0; +1.7]% when averaged over all imaged fractions. The LN CTV ΔD98% was [‐19.8; +1.2]% for single fractions and [‐3.1; +0.9]% after averaging. Mean (Standard deviation) absolute dose errors in DoseTracker of 107.8% (Std: 1.9%) for the prostate and 105.5% (Std:1.4%) for the LN were corrected during dose reconstruction by automatically calculated normalization factors. It resulted in accurate calculation of the motion‐induced dose errors with relative differences between DoseTracker and TPS dose calculations of ‐0.1% (Std: 0.5%) (prostate CTV ΔD99.5%) and ‐0.2% (Std: 0.5%) (LN CTV ΔD98%). The DoseTracker calculation was fast enough to keep up with the incoming inputs for all but two out of 107 184 dose calculations. Conclusion: Using the developed framework for dose perturbation monitoring, we found that the differential 6DoF target motion caused substantial dose perturbation for individual fractions, which largely averaged out after several fractions. The framework was shown to provide reliable dose calculations and a sufficiently high‐dose reconstruction speed to be applicable in real‐time. [ABSTRACT FROM AUTHOR]

Background: Anifrolumab, a monoclonal antibody targeting the type 1 interferon (IFN-I) signaling pathway, holds promise as a therapeutic intervention for systemic lupus erythematosus (SLE). However, its use is associated with an increased risk of infections, particularly viral infections like herpes zoster (HZ). Results from the clinical trials on anifrolumab show yearly rates of upper respiratory tract infections of 34% and HZ of 6.1%. An increased frequency of other specific viral infections, including herpes simplex virus (HSV), was not reported. Case Reports: Here, we present 2 cases of patients with SLE treated with anifrolumab, both experiencing severe adverse reactions in the form of disseminated herpesvirus infections, specifically disseminated HSV-2 and varicella zoster virus (VZV, HZ encephalitis). To the best of our knowledge, no previous reports of severe disseminated HSV-2 or HZ have been published in anifrolumab-treated patients. The patient in case 1 experienced a primary HSV-2 infection following anifrolumab treatment, potentially explaining the severity of the infection. The patient in case 2 had a history of previous HZ skin infections, which may have increased her risk of disseminated infection. Both patients recovered from the infections with minor sequelae, but they still require prophylactic antiviral treatment. These cases highlight the critical role of IFN-I immunity in protecting against herpesvirus infections. Conclusions: Thorough risk assessment before anifrolumab initiation, considering the patient's viral infection history, vaccination status, and potential exposure risks, is essential. Administration of recombinant zoster vaccine before anifrolumab therapy may benefit susceptible individuals. [ABSTRACT FROM AUTHOR]

Herpesvirus infections can lead to a number of severe clinical manifestations, particularly when involving the central nervous system (CNS), causing encephalitis and meningitis. However, understanding of the host factors conferring increased susceptibility to these diseases and their complications remains incomplete. Previous studies have uncovered defects in the innate Toll-like receptor 3 pathway and production of type I interferon (IFN-I) in children and adults that predispose them to herpes simplex encephalitis. More recently, there is accumulating evidence for an important role of IFN-independent cell-autonomous intrinsic mechanisms, including small nucleolar RNAs, RNA lariat metabolism, and autophagy, in restricting herpesvirus replication and conferring protection against CNS infection. The present review first describes clinical manifestations of HSV infection with a focus on neurological complications and then summarizes the host–pathogen interactions and innate immune pathways responsible for sensing herpesviruses and triggering antiviral responses and immunity. Next, we review the current landscape of inborn errors of immunity and the underlying genetic defects and disturbances of cellular immune pathways that confer increased susceptibility to HSV infection in CNS. Ultimately, we discuss some of the present outstanding unanswered questions relating to inborn errors of immunity and HSV CNS infection together with some perspectives and future directions for research in the pathogenesis of these severe diseases in humans.

BackgroundPersons with dementia tend to be vulnerable to mobility challenges and hence face a greater risk of fall and subsequent fractures, morbidity, and mortality. Motion-based technologies (MBTs), also called sensor-based technologies or virtual reality, have the potential for assisting physical exercise and training as a part of a disease management and rehabilitation program, but little is known about its' use for people with dementia. ObjectiveThe purpose of this pilot study was to investigate the feasibility and efficacy of MBT physical training at home for people with dementia. MethodsA 3-phase pilot study: (1) baseline start-up, (2) 15 weeks of group training at a local care center twice a week, and (3) 12 weeks of group training reduced to once a week, supplemented with individual MBT training twice a week at home. A total of 26 people with dementia from a municipality in Southern Denmark were eligible and agreed to participate in this study. Three withdrew from the study, leaving 23 participants for the final analysis. Feasibility was measured by the percentage of participants who trained with MBT at home, and their completion rate of total scheduled MBT sessions. Efficacy was evaluated by physical function, measured by Sit-to-Stand (STS), Timed-Up-and-Go (TUG), 6-minute Walk Test (6MW), and 10-meter Dual-task Walking Test (10MDW); cognitive function was measured by Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory-Questionnaire (NPI-Q); and European Quality of Life 5 dimensions questionnaire (EQOL5) was used for measuring quality of life. Descriptive statistics were applied accordingly. Wilcoxon signed-rank and rank-sum tests were applied to explore significant differences within and between the groups. ResultsAs much as 12 of 23 participants (52%) used the supplemental MBT training at home. Among them, 6 (50%) completed 75% or more scheduled sessions, 3 completed 25% or less, and 3 completed between 25% and 75% of scheduled sessions. For physical and cognitive function tests, supplementing with MBT training at home showed a tendency of overall stabilization of scores among the group of participants who actively trained with MBT; especially, the 10MDW test even showed a significant improvement from 9.2 to 7.1 seconds (P=.03). We found no positive effect on EQOL5 tests. ConclusionsMore than half of the study population with dementia used MBT training at home, and among them, half had an overall high adherence to the home training activity. Physical function tended to remain stable or even improved among high-adherence MBT individuals. We conclude that MBT training at home may be feasible for some individuals with dementia. Further research is warranted.

In recent years, there has been an increasing interest in immunomodulatory therapy as a means to treat various conditions, including infectious diseases. For instance, Toll-like receptor (TLR) agonists have been evaluated for treatment of genital herpes. However, although the TLR7 agonist imiquimod was shown to have antiviral activity in individual patients, no significant effects were observed in clinical trials, and the compound also exhibited significant side effects, including local inflammation. Cytosolic DNA is detected by the enzyme cyclic GMP-AMP (2'3'-cGAMP) synthase (cGAS) to stimulate antiviral pathways, mainly through induction of type I interferon (IFN)s. cGAS is activated upon DNA binding to produce the cyclic dinucleotide (CDN) 2'3'-cGAMP, which in turn binds and activates the adaptor protein Stimulator of interferon genes (STING), thus triggering type I IFN expression. In contrast to TLRs, STING is expressed broadly, including in epithelial cells. Here we report that natural and non-natural STING agonists strongly induce type I IFNs in human cells and in mice in vivo, without stimulating significant inflammatory gene expression. Systemic treatment with 2'3'-cGAMP reduced genital herpes simplex virus (HSV) 2 replication and improved the clinical outcome of infection. More importantly, local application of CDNs at the genital epithelial surface gave rise to local IFN activity, but only limited systemic responses, and this treatment conferred total protection against disease in both immunocompetent and immunocompromised mice. In direct comparison between CDNs and TLR agonists, only CDNs acted directly on epithelial cells, hence allowing a more rapid and IFN-focused immune response in the vaginal epithelium. Thus, specific activation of the STING pathway in the vagina evokes induction of the IFN system but limited inflammatory responses to allow control of HSV2 infections in vivo.

Long COVID (LC) is an emerging global health concern. The underlying mechanism and pathophysiology remain unclear. Presence of neutralizing autoantibodies against type 1 interferons (IFN) has been established as a predictor of critical COVID‐19. We hypothesized that persistent autoimmune activity with autoantibodies against type 1 IFN may contribute to symptoms in patients with LC. Plasma samples and clinical information were obtained from a Danish LC cohort consisting of adult patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. Information on symptoms and quality of life was derived from an LC‐specific questionnaire and the EQ‐5D‐5L questionnaire. Detection of type 1 IFN autoantibodies in plasma were performed by ELISA. Samples collected between June, 2020, and September, 2021, from 279 patients were analyzed and compared to a control group of 94 individuals with prior mild SARS‐CoV‐2 infection who did not develop LC symptoms. In total, five LC patients (1.8%) and 3 (3.2%) of the controls had detectable circulating type 1 IFN autoantibodies. Collectively, prevalence of autoantibodies against type 1 IFN subtypes in our LC cohort were primarily driven by men and did not exceed the prevalence in controls. Thus, in our cohort, anti‐type I IFN autoantibodies are unlikely to drive LC symptoms. [ABSTRACT FROM AUTHOR]

Human infection with parvovirus B19 causes a range of clinical manifestations, including benign erythema infectiosum in children, arthralgias in adults, aplastic crisis in patients with bone marrow failure, and potentially fatal congenital hydrops fetalis. Persistent parvovirus B19 infection is a rare disease presentation mostly seen in adult women or immunocompromised individuals. Treatment options include corticosteroids and intravenous immunoglobulin; however, viral clearance is difficult to obtain and rarely maintained. In this Grand Round, we report the case of a 43-year-old man with persistent parvovirus B19 infection and anaemia, who was refractory to standard treatment regimens, and whom we successfully treated with pegylated interferon alfa-2a. Initial treatment led to viral clearance and remission of anaemia, although secondary recurrence of virus required treatment extension. Despite extensive genetic and immunological evaluations, no underlying primary or secondary immunodeficiency was identified in the patient. We propose interferon alfa-2a as a treatment option for persistent parvovirus B19 infection and advocate long-term follow-up of patients and potentially repeated treatment. [ABSTRACT FROM AUTHOR]