Simian varicella virus infection and reactivation in rhesus macaques trigger cytokine and Aß40/42 alterations in serum and cerebrospinal fluid.

Simian varicella virus (SVV) produces peripheral inflammatory responses during varicella (primary infection) and zoster (reactivation) in rhesus macaques (RM). However, it is unclear if peripheral measures are accurate proxies for central nervous system (CNS) responses. Thus, we analyzed cytokine and Aß42/Aß40 changes in paired serum and cerebrospinal fluid (CSF) during the course of infection. During varicella and zoster, every RM had variable changes in serum and CSF cytokine and Aß42/Aß40 levels compared to pre-inoculation levels. Overall, peripheral infection appears to affect CNS cytokine and Aß42/Aß40 levels independent of serum responses, suggesting that peripheral disease may contribute to CNS disease.

Trigeminal Postherpetic Neuralgia: From Pathophysiology to Treatment.

PURPOSE OF REVIEW: Trigeminal postherpetic neuralgia (TG-PHN) is a neuropathic pain condition complicating herpes zoster (HZ) attributed to the trigeminal nerve. It poses significant challenges due to its persistent and debilitating nature. This review explores the clinical characteristics of TG-PHN, analyzes its pathophysiological underpinnings, and addresses existent and potential therapies. RECENT FINDINGS: TG-PHN is one of the most common and complex PHN locations. It has distinguishing clinical and pathophysiological characteristics, starting with viral triggered injuries to the trigeminal ganglion (TG) and peripheral tissue and involving the ascending and descending brain modulation pathways. Current therapies include vaccines, oral and topical medications, and interventional approaches, like nerve blocks and neurostimulation. This review covers TG-PHN's clinical and physiological components, treatment options, and potential future targets for improved management. By exploring the complexities of this condition, we aim to contribute to developing more effective and targeted therapies for patients suffering from trigeminal PHN.

Simian Varicella Virus Infection and Reactivation in Rhesus Macaques Trigger Cytokine and Aß40/42 Alterations in Serum and Cerebrospinal Fluid.

Simian varicella virus (SVV) produces peripheral inflammatory responses during varicella (primary infection) and zoster (reactivation) in rhesus macaques (RM). However, it is unclear if peripheral measures are accurate proxies for central nervous system (CNS) responses. Thus, we analyzed cytokine and Aß42/Aß40 changes in paired serum and cerebrospinal fluid (CSF) during the course of infection. During varicella and zoster, every RM had variable changes in serum and CSF cytokine and Aß42/Aß40 levels compared to pre-inoculation levels. Overall, peripheral infection appears to affect CNS cytokine and Aß42/Aß40 levels independent of serum responses, suggesting that peripheral disease may contribute to CNS disease.

Multiple sclerosis plasma IgG aggregates induce complement-dependent neuronal apoptosis.

Grey matter pathology is central to the progression of multiple sclerosis (MS). We discovered that MS plasma immunoglobulin G (IgG) antibodies, mainly IgG1, form large aggregates (>100 nm) which are retained in the flow-through after binding to Protein A. Utilizing an annexin V live-cell apoptosis detection assay, we demonstrated six times higher levels of neuronal apoptosis induced by MS plasma IgG aggregates (n = 190, from two cohorts) compared to other neurological disorders (n = 116) and healthy donors (n = 44). MS IgG aggregate-mediated, complement-dependent neuronal apoptosis was evaluated in multiple model systems including primary human neurons, primary human astrocytes, neuroblastoma SH-SY5Y cells, and newborn mouse brain slices. Immunocytochemistry revealed the co-deposition of IgG, early and late complement activation products (C1q, C3b, and membrane attack complex C5b9), as well as active caspase 3 in treated neuronal cells. Furthermore, we found that MS plasma cytotoxic antibodies are not present in Protein G flow-through, nor in the paired plasma. The neuronal apoptosis can be inhibited by IgG depletion, disruption of IgG aggregates, pan-caspase inhibitor, and is completely abolished by digestion with IgG-cleaving enzyme IdeS. Transmission electron microscopy and nanoparticle tracking analysis revealed the sizes of MS IgG aggregates are greater than 100 nm. Our data support the pathological role of MS IgG antibodies and corroborate their connection to complement activation and axonal damage, suggesting that apoptosis may be a mechanism of neurodegeneration in MS.

Signatures for viral infection and inflammation in the proximal olfactory system in familial Alzheimer's disease.

Alzheimer's disease (AD) is characterized by deficits in olfaction and olfactory pathology preceding diagnosis of dementia. Here we analyzed differential gene and protein expression in the olfactory bulb (OB) and tract (OT) of familial AD (FAD) individuals carrying the autosomal dominant presenilin 1 E280A mutation. Compared to control, FAD OT had increased immunostaining for ß-amyloid (Aß) and CD68 in high and low myelinated regions, as well as increased immunostaining for Iba1 in the high myelinated region. In FAD samples, RNA sequencing showed: (1) viral infection in the OB; (2) inflammation in the OT that carries information via entorhinal cortex from the OB to hippocampus, a brain region essential for learning and memory; and (3) decreased oligodendrocyte deconvolved transcripts. Interestingly, spatial proteomic analysis confirmed altered myelination in the OT of FAD individuals, implying dysfunction of communication between the OB and hippocampus. These findings raise the possibility that viral infection and associated inflammation and dysregulation of myelination of the olfactory system may disrupt hippocampal function, contributing to acceleration of FAD progression.

Zoster-Associated Prothrombotic Plasma Exosomes and Increased Stroke Risk.

Herpes zoster (HZ; shingles) caused by varicella zoster virus reactivation increases stroke risk for up to 1 year after HZ. The underlying mechanisms are unclear, however, the development of stroke distant from the site of zoster (eg, thoracic, lumbar, sacral) that can occur months after resolution of rash points to a long-lasting, virus-induced soluble factor (or factors) that can trigger thrombosis and/or vasculitis. Herein, we investigated the content and contributions of circulating plasma exosomes from HZ and non-HZ patient samples. Compared with non-HZ exosomes, HZ exosomes (1) contained proteins conferring a prothrombotic state to recipient cells and (2) activated platelets leading to the formation of platelet-leukocyte aggregates. Exosomes 3 months after HZ yielded similar results and also triggered cerebrovascular cells to secrete the proinflammatory cytokines, interleukin 6 and 8. These results can potentially change clinical practice through addition of antiplatelet agents for HZ and initiatives to increase HZ vaccine uptake to decrease stroke risk.

A phase I/Ib trial and biological correlate analysis of neoadjuvant SBRT with single-dose durvalumab in HPV-unrelated locally advanced HNSCC.

Five-year survival for human papilloma virus-unrelated head and neck squamous cell carcinomas remain below 50%. We assessed the safety of administering combination hypofractionated stereotactic body radiation therapy with single-dose durvalumab (anti-PD-L1) neoadjuvantly (n = 21) ( NCT03635164 ). The primary endpoint of the study was safety, which was met. Secondary endpoints included radiographic, pathologic and objective response; locoregional control; progression-free survival; and overall survival. Among evaluable patients at an early median follow-up of 16 months (448 d or 64 weeks), overall survival was 80.1% with 95% confidence interval (95% CI) (62.0%, 100.0%), locoregional control and progression-free survival were 75.8% with 95% CI (57.5%, 99.8%), and major pathological response or complete response was 75% with 95% exact CI (51.6%, 100.0%). For patients treated with 24 Gy, 89% with 95% CI (57.1%, 100.0%) had MPR or CR. Using high-dimensional multi-omics and spatial data as well as biological correlatives, we show that responders had: (1) an increase in effector T cells; (2) a decrease in immunosuppressive cells; and (3) an increase in antigen presentation post-treatment.

Simian Varicella Virus Pathogenesis in Skin during Varicella and Zoster.

Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2-127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing ß-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread.

VZV Infection of Primary Human Adrenal Cortical Cells Produces a Proinflammatory Environment without Cell Death.

Virus infection of adrenal glands can disrupt secretion of mineralocorticoids, glucocorticoids, and sex hormones from the cortex and catecholamines from the medulla, leading to a constellation of symptoms such as fatigue, dizziness, weight loss, nausea, and muscle and joint pain. Specifically, varicella zoster virus (VZV) can produce bilateral adrenal hemorrhage and adrenal insufficiency during primary infection or following reactivation. However, the mechanisms by which VZV affects the adrenal glands are not well-characterized. Herein, we determined if primary human adrenal cortical cells (HAdCCs) infected with VZV support viral replication and produce a proinflammatory environment. Quantitative PCR showed VZV DNA increasing over time in HAdCCs, yet no cell death was seen at 3 days post-infection by TUNEL staining or Western Blot analysis with PARP and caspase 9 antibodies. Compared to conditioned supernatant from mock-infected cells, supernatant from VZV-infected cells contained significantly elevated IL-6, IL-8, IL-12p70, IL-13, IL-4, and TNF-α. Overall, VZV can productively infect adrenal cortical cells in the absence of cell death, suggesting that these cells may be a potential reservoir for ongoing viral replication and proinflammatory cytokine production, leading to chronic adrenalitis and dysfunction.

Azadirachta indica A. Juss bark extract and its Nimbin isomers restrict ß-coronaviral infection and replication.

Emerging mutations in the SARS-CoV-2 genome pose a challenge for vaccine development and antiviral therapy. The antiviral efficacy of Azadirachta indica bark extract (NBE) was assessed against SARS-CoV-2 and m-CoV-RSA59 infection. Effects of in vivo intranasal or oral NBE administration on viral load, inflammatory response, and histopathological changes were assessed in m-CoV-RSA59-infection. NBE administered inhibits SARS-CoV-2 and m-CoV-RSA59 infection and replication in vitro, reducing Envelope and Nucleocapsid gene expression. NBE ameliorates neuroinflammation and hepatitis in vivo by restricting viral replication and spread. Isolated fractions of NBE enriched in Nimbin isomers shows potent inhibition of m-CoV-RSA59 infection in vitro. In silico studies revealed that NBE could target Spike and RdRp of m-CoV and SARS-CoV-2 with high affinity. NBE has a triterpenoids origin that may allow them to competitively target panoply of viral proteins to inhibit mouse and different strains of human coronavirus infections, suggesting its potential as an antiviral against pan-ß-Coronaviruses.

Targeted RNA Sequencing of VZV-Infected Brain Vascular Adventitial Fibroblasts Indicates That Amyloid May Be Involved in VZV Vasculopathy.

BACKGROUND AND OBJECTIVES: Compared with stroke controls, patients with varicella zoster virus (VZV) vasculopathy have increased amyloid in CSF, along with increased amylin (islet amyloid polypeptide [IAPP]) and anti-VZV antibodies. Thus, we examined the gene expression profiles of VZV-infected primary human brain vascular adventitial fibroblasts (HBVAFs), one of the initial arterial cells infected in VZV vasculopathy, to determine whether they are a potential source of amyloid that can disrupt vasculature and potentiate inflammation. METHODS: Mock- and VZV-infected quiescent HBVAFs were harvested at 3 days postinfection. Targeted RNA sequencing of the whole-human transcriptome (BioSpyder Technologies, TempO-Seq) was conducted followed by gene set enrichment and pathway analysis. Selected pathways unique to VZV-infected cells were confirmed by enzyme-linked immunoassays, migration assays, and immunofluorescence analysis (IFA) that included antibodies against amylin and amyloid-beta, as well as amyloid staining by Thioflavin-T. RESULTS: Compared with mock, VZV-infected HBVAFs had significantly enriched gene expression pathways involved in vascular remodeling and vascular diseases; confirmatory studies showed secretion of matrix metalloproteinase-3 and -10, as well increased migration of infected cells and uninfected cells when exposed to conditioned media from VZV-infected cells. In addition, significantly enriched pathways involved in amyloid-associated diseases (diabetes mellitus, amyloidosis, and Alzheimer disease), tauopathy, and progressive neurologic disorder were identified; predicted upstream regulators included amyloid precursor protein, apolipoprotein E, microtubule-associated protein tau, presenilin 1, and IAPP. Confirmatory IFA showed that VZV-infected HBVAFs contained amyloidogenic peptides (amyloid-beta and amylin) and intracellular amyloid. DISCUSSION: Gene expression profiles and pathway enrichment analysis of VZV-infected HBVAFs, as well as phenotypic studies, reveal features of pathologic vascular remodeling (e.g., increased cell migration and changes in the extracellular matrix) that can contribute to cerebrovascular disease. Furthermore, the discovery of amyloid-associated transcriptional pathways and intracellular amyloid deposition in HBVAFs raise the possibility that VZV vasculopathy is an amyloid disease. Amyloid deposition may contribute to cell death and loss of vascular wall integrity, as well as potentiate chronic inflammation in VZV vasculopathy, with disease severity and recurrence determined by the host's ability to clear virus infection and amyloid deposition and by the coexistence of other amyloid-associated diseases (i.e., Alzheimer disease and diabetes mellitus).

Targeted RNA Sequencing of Formalin-Fixed, Paraffin-Embedded Temporal Arteries From Giant Cell Arteritis Cases Reveals Viral Signatures.

BACKGROUND AND OBJECTIVES: Varicella zoster virus (VZV) antigen has been detected in temporal arteries (TAs) of individuals with giant cell arteritis (GCA), the most common systemic vasculitis in older adults. Thus, we explored the contribution of VZV to GCA pathogenesis. METHODS: Formalin-fixed, paraffin-embedded TA sections from biopsy-positive GCA participants with VZV antigen (GCA/VZV-positive; n = 20) and without (GCA/VZV-negative, n = 20) and from normal participants with VZV antigen (control/VZV-positive, n = 11) and without (control/VZV-negative, n = 20) were analyzed by targeted RNA sequencing of the whole human transcriptome (BioSpyder TempO-Seq). Ingenuity pathway analysis and R-computational program were used to identify differentially expressed genes and pathways between groups. RESULTS: Compared with control/VZV-negative TAs, GCA/VZV-negative and GCA/VZV-positive TAs were significantly enriched for human transcripts specific for pathways involved in viral infections, including viral entry, nuclear factor kappa B activation by viruses, and other pathogen-related immune activation pathways. Similarly, human gene sets supporting viral infection were found in control/VZV-positive TAs that showed no morphological signs of inflammation, suggesting that the enriched pathways were not nonspecific signatures of infiltrating immune cells. All GCA TAs and control/VZV-positive TAs showed enrichment of transcripts involved in vascular remodeling, including smooth muscle cell migration. DISCUSSION: The detection of viral and immune activation pathways in GCA TAs supports a role for virus infection in GCA pathogenesis. In addition, the detection of viral pathways in control/VZV-positive TAs, along with vascular remodeling pathways, suggests that these samples may represent early infection with progression to clinical disease, depending on host and other environmental factors.

Histopathological Analysis of Adrenal Glands after Simian Varicella Virus Infection.

Latent varicella zoster virus (VZV) has been detected in human adrenal glands, raising the possibility of virus-induced adrenal damage and dysfunction during primary infection or reactivation. Rare cases of bilateral adrenal hemorrhage and insufficiency associated with VZV reactivation have been reported. Since there is no animal model for VZV infection of adrenal glands, we obtained adrenal glands from two non-human primates (NHPs) that spontaneously developed varicella from primary simian varicella virus (SVV) infection, the NHP VZV homolog. Histological and immunohistochemical analysis revealed SVV antigen and DNA in the adrenal medulla and cortex of both animals. Adrenal glands were observed to have Cowdry A inclusion bodies, cellular necrosis, multiple areas of hemorrhage, and varying amounts of polymorphonuclear cells. No specific association of SVV antigen with ßIII-tubulin-positive nerve fibers was found. Overall, we found that SVV can productively infect NHP adrenal glands, and is associated with inflammation, hemorrhage, and cell death. These findings suggest that further studies are warranted to examine the contribution of VZV infection to human adrenal disease. This study also suggests that VZV infection may present itself as acute adrenal dysfunction with "long-hauler" symptoms of fatigue, weakness, myalgias/arthralgias, and hypotension.

Transcriptional profiling reveals potential involvement of microvillous TRPM5-expressing cells in viral infection of the olfactory epithelium.

BACKGROUND: Understanding viral infection of the olfactory epithelium is essential because the olfactory nerve is an important route of entry for viruses to the central nervous system. Specialized chemosensory epithelial cells that express the transient receptor potential cation channel subfamily M member 5 (TRPM5) are found throughout the airways and intestinal epithelium and are involved in responses to viral infection. RESULTS: Herein we performed deep transcriptional profiling of olfactory epithelial cells sorted by flow cytometry based on the expression of mCherry as a marker for olfactory sensory neurons and for eGFP in OMP-H2B::mCherry/TRPM5-eGFP transgenic mice (Mus musculus). We find profuse expression of transcripts involved in inflammation, immunity and viral infection in TRPM5-expressing microvillous cells compared to olfactory sensory neurons. CONCLUSION: Our study provides new insights into a potential role for TRPM5-expressing microvillous cells in viral infection of the olfactory epithelium. We find that, as found for solitary chemosensory cells (SCCs) and brush cells in the airway epithelium, and for tuft cells in the intestine, the transcriptome of TRPM5-expressing microvillous cells indicates that they are likely involved in the inflammatory response elicited by viral infection of the olfactory epithelium.

Detection of varicella zoster virus antigen and DNA in two cases of cerebral amyloid angiopathy.

OBJECTIVE: Varicella zoster virus (VZV) vasculopathy and cerebral amyloid angiopathy (CAA) have similar clinical presentations: both affect cerebrovasculature in the elderly, produce hemorrhage, and can have a protracted course of cognitive decline and other neurological deficits. The cause of CAA is unknown, but amyloid-beta (Aß) is found within arterial walls. Recent studies show that VZV induces Aß and amylin expression and an amyloid-promoting environment. Thus, we determined if VZV was present in CAA-affected arteries. METHODS: Two subjects with pathologically-verified CAA were identified postmortem and frontal lobes analyzed by immunohistochemistry for arteries containing VZV, Aß, and amylin and H&E for pathological changes. VZV antigen detection was confirmed by PCR for VZV DNA in the same region. RESULTS: In both CAA cases, sections with cerebral arteries containing VZV antigen with corresponding VZV DNA were identified; VZV antigen co-localized with Aß in media of arteries with histological changes characteristic of CAA. Amylin was also seen in the intima of a VZV-positive artery in the diabetic subject. Not all Aß-containing arteries had VZV, but all VZV-positive arteries contained Aß. CONCLUSIONS: VZV antigen co-localized with Aß in some affected arteries from two CAA cases, suggesting a possible association between VZV infection and CAA.

Amylin, Aß42, and Amyloid in Varicella Zoster Virus Vasculopathy Cerebrospinal Fluid and Infected Vascular Cells.

BACKGROUND: Varicella zoster virus (VZV) vasculopathy is characterized by persistent arterial inflammation leading to stroke. Studies show that VZV induces amyloid formation that may aggravate vasculitis. Thus, we determined if VZV central nervous system infection produces amyloid. METHODS: Aß peptides, amylin, and amyloid were measured in cerebrospinal fluid (CSF) from 16 VZV vasculopathy subjects and 36 stroke controls. To determine if infection induced amyloid deposition, mock- and VZV-infected quiescent primary human perineurial cells (qHPNCs), present in vasculature, were analyzed for intracellular amyloidogenic transcripts/proteins and amyloid. Supernatants were assayed for amyloidogenic peptides and ability to induce amyloid formation. To determine amylin's function during infection, amylin was knocked down with small interfering RNA and viral complementary DNA (cDNA) was quantitated. RESULTS: Compared to controls, VZV vasculopathy CSF had increased amyloid that positively correlated with amylin and anti-VZV antibody levels; Aß40 was reduced and Aß42 unchanged. Intracellular amylin, Aß42, and amyloid were seen only in VZV-infected qHPNCs. VZV-infected supernatant formed amyloid fibrils following addition of amyloidogenic peptides. Amylin knockdown decreased viral cDNA. CONCLUSIONS: VZV infection increased levels of amyloidogenic peptides and amyloid in CSF and qHPNCs, indicating that VZV-induced amyloid deposition may contribute to persistent arterial inflammation in VZV vasculopathy. In addition, we identified a novel proviral function of amylin.

Elevated serum substance P during simian varicella virus infection in rhesus macaques: implications for chronic inflammation and adverse cerebrovascular events.

Varicella and zoster, produced by varicella-zoster virus (VZV), are associated with an increased risk of stroke that may be due to persistent inflammation and hypercoagulability. Because substance P is associated with inflammation, hypercoagulability, and atherosclerotic plaque rupture that may contribute to increased stroke risk after VZV infection, we measured serum substance P in simian varicella virus-infected rhesus macaques. We found significantly increased and persistent serum substance P concentrations during varicella and zoster compared with pre-inoculation, supporting the hypothesis that VZV-induced increases in serum substance P may contribute to increased stroke risk associated with VZV infection.