Chemokine-mediated cell migration into the central nervous system in progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) has been associated with different forms of immune compromise. This study analyzes the chemokine signals and attracted immune cells in cerebrospinal fluid (CSF) during PML to define immune cell subpopulations relevant for the PML immune response. In addition to chemokines that indicate a general state of inflammation, like CCL5 and CXCL10, the CSF of PML patients specifically contains CCL2 and CCL4.

Harnessing regulatory T cells to establish immune tolerance.

Engineered regulatory T (T) cells have emerged as precision therapeutics aimed at inducing immune tolerance while reducing the risks associated with generalized immunosuppression. This Viewpoint highlights the opportunities and challenges for engineered T cell therapies in treating autoimmune and other inflammatory diseases.

Pharmacokinetic and Target Engagement Measures of ANX007, an Anti-C1q Antibody Fragment, Following Intravitreal Administration in Nonhuman Primates.

Purpose: C1q and the classical complement cascade are key regulators of synaptic pruning, and their aberrant activation has been implicated in neurodegenerative ophthalmic diseases including geographic atrophy and glaucoma. The antigen-binding fragment antibody ANX007 specifically recognizes globular head groups of C1q to block substrate binding and functionally inhibit classical complement cascade activation. ANX007 was assessed in nonclinical studies of biodistribution and C1q target engagement in the eye following intravitreal (IVT) administration in cynomolgus monkeys.

Abnormalities in normal-appearing white matter from which multiple sclerosis lesions arise.

Normal-appearing white matter is far from normal in multiple sclerosis; little is known about the precise pathology or spatial pattern of this alteration and its relation to subsequent lesion formation. This study was undertaken to evaluate normal-appearing white matter abnormalities in brain areas where multiple sclerosis lesions subsequently form, and to investigate the spatial distribution of normal-appearing white matter abnormalities in persons with multiple sclerosis. Brain MRIs of pre-lesion normal-appearing white matter were analysed in participants with new T2 lesions, pooled from three clinical trials: SYNERGY (NCT01864148; = 85 with relapsing multiple sclerosis) was the test data set; ASCEND (NCT01416181; = 154 with secondary progressive multiple sclerosis) and ADVANCE (NCT00906399; = 261 with relapsing-remitting multiple sclerosis) were used as validation data sets.

MOG autoantibodies trigger a tightly-controlled FcR and BTK-driven microglia proliferative response.

Autoantibodies are a hallmark of numerous neurological disorders, including multiple sclerosis, autoimmune encephalitides and neuromyelitis optica. Whilst well understood in peripheral myeloid cells, the pathophysiological significance of autoantibody-induced Fc receptor signalling in microglia remains unknown, in part due to the lack of a robust in vivo model. Moreover, the application of therapeutic antibodies for neurodegenerative disease also highlights the importance of understanding Fc receptor signalling in microglia.

A Novel Panel of Rabbit Monoclonal Antibodies and Their Diverse Applications Including Inhibition of Epsilon Toxin Oligomerization.

The pore-forming epsilon toxin (ETX) produced by is among the most lethal bacterial toxins known. Sensitive antibody-based reagents are needed to detect toxin, distinguish mechanisms of cell death, and prevent ETX toxicity. Using B-cell immuno-panning and cloning techniques, seven ETX-specific monoclonal antibodies were generated from immunized rabbits.

Cell-autonomous and non-cell autonomous effects of neuronal BIN1 loss in vivo.

BIN1 is the most important risk locus for Late Onset Alzheimer's Disease (LOAD), after ApoE. BIN1 AD-associated SNPs correlate with Tau deposition as well as with brain atrophy. Furthermore, the level of neuronal-specific BIN1 isoform 1 protein is decreased in sporadic AD cases in parallel with neuronal loss, despite an overall increase in BIN1 total mRNA.

BIN1 favors the spreading of Tau via extracellular vesicles.

Despite Bridging INtegrator 1 (BIN1) being the second most statistically-significant locus associated to Late Onset Alzheimer's Disease, its role in disease pathogenesis remains to be clarified. As reports suggest a link between BIN1, Tau and extracellular vesicles, we investigated whether BIN1 could affect Tau spreading via exosomes secretion. We observed that BIN1-associated Tau-containing extracellular vesicles purified from cerebrospinal fluid of AD-affected individuals are seeding-competent.

Epstein-Barr-Virus-Induced One-Carbon Metabolism Drives B Cell Transformation.

Epstein-Barr virus (EBV) causes Burkitt, Hodgkin, and post-transplant B cell lymphomas. How EBV remodels metabolic pathways to support rapid B cell outgrowth remains largely unknown. To gain insights, primary human B cells were profiled by tandem-mass-tag-based proteomics at rest and at nine time points after infection; >8,000 host and 29 viral proteins were quantified, revealing mitochondrial remodeling and induction of one-carbon (1C) metabolism.

Identification of regulators of the myofibroblast phenotype of primary dermal fibroblasts from early diffuse systemic sclerosis patients.

Systemic sclerosis (SSc or scleroderma) is an auto-immune disease characterized by skin fibrosis. While primary cells from patients are considered as a unique resource to better understand human disease biology, the effect of in vitro culture on these cells and their evaluation as a platform to identify disease regulators remain poorly characterized. The goal of our studies was to provide insights into the utility of SSc dermal fibroblast primary cells for therapeutic target discovery.

Polyomavirus T Antigen Induces Expression Using an LXCXE-Dependent and TP53-Independent Mechanism.

APOBEC3B is a single-stranded DNA cytosine deaminase with beneficial innate antiviral functions. However, misregulated APOBEC3B can also be detrimental by inflicting APOBEC signature C-to-T and C-to-G mutations in genomic DNA of multiple cancer types. Polyomavirus and papillomavirus oncoproteins induce APOBEC3B overexpression, perhaps to their own benefit, but little is known about the cellular mechanisms hijacked by these viruses to do so.

CDK12-mediated transcriptional regulation of noncanonical NF-κB components is essential for signaling.

Members of the family of nuclear factor κB (NF-κB) transcription factors are critical for multiple cellular processes, including regulating innate and adaptive immune responses, cell proliferation, and cell survival. Canonical NF-κB complexes are retained in the cytoplasm by the inhibitory protein IκBα, whereas noncanonical NF-κB complexes are retained by p100. Although activation of canonical NF-κB signaling through the IκBα kinase complex is well studied, few regulators of the NF-κB-inducing kinase (NIK)-dependent processing of noncanonical p100 to p52 and the subsequent nuclear translocation of p52 have been identified.

Investigating small molecules to inhibit germinal center kinase-like kinase (GLK/MAP4K3) upstream of PKCθ phosphorylation: Potential therapy to modulate T cell dependent immunity.

Germinal center kinase-like kinase (GLK, also known as MAP4K3) has been hypothesized to have an effect on key cellular activities, including inflammatory responses. GLK is required for activation of protein kinase C-θ (PKCθ) in T cells. Controlling the activity of T helper cell responses could be valuable for the treatment of autoimmune diseases.

Infectious Entry and Neutralization of Pathogenic JC Polyomaviruses.

Progressive multifocal leukoencephalopathy (PML) is a lethal brain disease caused by uncontrolled replication of JC polyomavirus (JCV). JCV strains recovered from the brains of PML patients carry mutations that prevent the engagement of sialylated glycans, which are thought to serve as receptors for the infectious entry of wild-type JCV. In this report, we show that non-sialylated glycosaminoglycans (GAGs) can serve as alternative attachment receptors for the infectious entry of both wild-type and PML mutant JCV strains.

Distribution and Quantity of Sites of John Cunningham Virus Persistence in Immunologically Healthy Patients: Correlation With John Cunningham Virus Antibody and Urine John Cunningham Virus DNA.

Importance: Although seroepidemiological studies indicate that greater than 50% of the population has been infected with John Cunningham virus (JCV), the sites of JCV persistence remain incompletely characterized.

Objective: To determine sites of JCV persistence in immunologically healthy individuals.

Design, Setting, And Participants: Tissue specimens from multiple sites including brain, renal, and nonrenal tissues were obtained at autopsy performed in the Department of Pathology at the University of Kentucky from 12 immunologically healthy patients between February 9, 2011, and November 27, 2012.

Inhibition of JCPyV infection mediated by targeted viral genome editing using CRISPR/Cas9.

Progressive multifocal leukoencephalopathy (PML) is a debilitating disease resulting from infection of oligodendrocytes by the JC polyomavirus (JCPyV). Currently, there is no anti-viral therapeutic available against JCPyV infection. The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system (CRISPR/Cas9) is a genome editing tool capable of introducing sequence specific breaks in double stranded DNA.

JC Polyomavirus Abundance and Distribution in Progressive Multifocal Leukoencephalopathy (PML) Brain Tissue Implicates Myelin Sheath in Intracerebral Dissemination of Infection.

Over half of adults are seropositive for JC polyomavirus (JCV), but rare individuals develop progressive multifocal leukoencephalopathy (PML), a demyelinating JCV infection of the central nervous system. Previously, PML was primarily seen in immunosuppressed patients with AIDS or certain cancers, but it has recently emerged as a drug safety issue through its association with diverse immunomodulatory therapies. To better understand the relationship between the JCV life cycle and PML pathology, we studied autopsy brain tissue from a 70-year-old psoriasis patient on the integrin alpha-L inhibitor efalizumab following a ~2 month clinical course of PML.

CD62L is not a reliable biomarker for predicting PML risk in natalizumab-treated R-MS patients.

Objective: To assess if the percentage of CD3(+)CD4(+)CD62L(+) cells in cryopreserved peripheral blood mononuclear cells (PBMCs) (here termed %CD62L) can predict risk of developing progressive multifocal leukoencephalopathy (PML) and better inform the physician for benefit-risk assessment of natalizumab treatment decisions in a global setting.

Methods: Cryopreserved PBMCs from 21 natalizumab-treated patients who developed PML and 104 matched natalizumab-treated patients with multiple sclerosis (MS) without PML collected as a part of Biogen clinical trials were retrospectively examined for CD3, CD4, CCR7, CD45RA, and CD62L by flow cytometry.

Results: In this cohort, %CD62L in natalizumab-treated patients did not predict PML risk.

The NF-κB genomic landscape in lymphoblastoid B cells.

The nuclear factor κB (NF-κΒ) subunits RelA, RelB, cRel, p50, and p52 are each critical for B cell development and function. To systematically characterize their responses to canonical and noncanonical NF-κB pathway activity, we performed chromatin immunoprecipitation followed by high-throughput DNA sequencing (ChIP-seq) analysis in lymphoblastoid B cell lines (LCLs). We found a complex NF-κB-binding landscape, which did not readily reflect the two NF-κB pathway paradigms.

Pharmacogenomics: novel loci identification via integrating gene differential analysis and eQTL analysis.

Nearly one-half of asthmatic patients do not respond to the most commonly prescribed controller therapy, inhaled corticosteroids (ICS). We conducted an expression quantitative trait loci (eQTL) analysis using >300 expression microarrays (from 117 lymphoblastoid cell lines) in corticosteroid (dexamethasone) treated and untreated cells derived from asthmatic subjects in the Childhood Asthma Management Program (CAMP) clinical trial. We then tested the associations of eQTL with longitudinal change in airway responsiveness to methacholine (LnPC20) on ICS.

Autophagy prolongs survival after NFκB inhibition in B-cell lymphomas.

Autophagy allows cells to survive under conditions of nutrient deprivation. We have demonstrated that autophagy inhibitors are synthetically lethal with NFκB inhibitors in B-cell lymphomas because the NFκB pathway promotes survival by increasing glucose import. When NFκB is inhibited in B-cell lymphoma, glucose import decreases and cells become sensitive to perturbations in mitochondrial metabolism and autophagy.

Genome-wide siRNA screen for mediators of NF-κB activation.

Although canonical NFκB is frequently critical for cell proliferation, survival, or differentiation, NFκB hyperactivation can cause malignant, inflammatory, or autoimmune disorders. Despite intensive study, mammalian NFκB pathway loss-of-function RNAi analyses have been limited to specific protein classes. We therefore undertook a human genome-wide siRNA screen for novel NFκB activation pathway components.

IKKβ and NF-κB transcription govern lymphoma cell survival through AKT-induced plasma membrane trafficking of GLUT1.

All cancer cells require increased nutrient uptake to support proliferation. In this study, we investigated the signals that govern glucose uptake in B-cell lymphomas and determined that the inhibitor of NF-κB-kinase β (IKKβ) induced glucose transporter-1 (GLUT1) membrane trafficking in both viral and spontaneous B-cell lymphomas. IKKβ induced AKT activity, whereas IKKβ-driven NF-κB transcription was required for GLUT1 surface localization downstream of AKT.

Latent membrane protein 1 is dispensable for Epstein-Barr virus replication in human embryonic kidney 293 cells.

Epstein Barr Virus (EBV) replicates in oral epithelial cells and gains entry to B-lymphocytes. In B-lymphocytes, EBV expresses a restricted subset of genes, the Latency III program, which converts B-lymphocytes to proliferating lymphoblasts. Latent Membrane Protein 1 (LMP1) and the other Latency III associated proteins are also expressed during virus replication.