A Tiny Pocket Packs a Punch: Leveraging Pyridones for the Discovery of CNS-Penetrant Aza-indazole IRAK4 Inhibitors.

We herein report the discovery, synthesis, and evolution of a series of indazoles and azaindazoles as CNS-penetrant IRAK4 inhibitors. Described is the use of structure-based and property-based drug design strategically leveraged to guide the property profile of a key series into a favorable property space while maintaining potency and selectivity. Our rationale that led toward functionalities with potency improvements, CNS-penetration, solubility, and favorable drug-like properties is portrayed.

Discovery of BIO-8169─A Highly Potent, Selective, and Brain-Penetrant IRAK4 Inhibitor for the Treatment of Neuroinflammation.

Interleukin receptor associated kinase 4 (IRAK4) plays an important role in innate immune signaling through Toll-like and interleukin-1 receptors and represents an attractive target for the treatment of inflammatory diseases and cancer. We previously reported the development of a potent, selective, and brain-penetrant imidazopyrimidine series of IRAK4 inhibitors. However, lead molecule BIO-7488 () suffered from low solubility which led to variable PK, compound accumulation, and poor in vivo tolerability.

The Discovery of 7-Isopropoxy-2-(1-methyl-2-oxabicyclo[2.1.1]hexan-4-yl)--(6-methylpyrazolo[1,5-]pyrimidin-3-yl)imidazo[1,2-]pyrimidine-6-carboxamide (BIO-7488), a Potent, Selective, and CNS-Penetrant IRAK4 Inhibitor for the Treatment of Ischemic Stroke.

Interleukin receptor-associated kinase 4 (IRAK4) is a key node of signaling within the innate immune system that regulates the production of inflammatory cytokines and chemokines. The presence of amage-ssociated olecular patterns (DAMPs) after tissue damage such as stroke or traumatic brain injury (TBI) initiates signaling through the IRAK4 pathway that can lead to a feed-forward inflammatory loop that can ultimately hinder patient recovery. Herein, we describe the first potent, selective, and CNS-penetrant IRAK4 inhibitors for the treatment of neuroinflammation.

Interferon-α receptor antisense oligonucleotides reduce neuroinflammation and neuropathology in a mouse model of cerebral interferonopathy.

Chronic and elevated levels of the antiviral cytokine IFN-α in the brain are neurotoxic. This is best observed in patients with genetic cerebral interferonopathies such as Aicardi-Goutières syndrome. Cerebral interferonopathies typically manifest in early childhood and lead to debilitating disease and premature death.

Control of enhancer and promoter activation in the type I interferon response by the histone demethylase Kdm4d/JMJD2d.

Introduction: Transcriptional activation depends on the interplay of chromatin modifiers to establish a permissive epigenetic landscape. While histone 3 lysine 9 (H3K9) methylation has long been associated with gene repression, there is limited evidence to support a role for H3K9 demethylases in gene activation.

Methods: We leveraged knockdown and overexpression of JMJD2d / Kdm4d in mouse embryonic fibroblasts, coupled with extensive epigenomic analysesm to decipher the role of histone 3 lysine 9 demethylases in the innate immune response.

The impact of rare protein coding genetic variation on adult cognitive function.

Compelling evidence suggests that human cognitive function is strongly influenced by genetics. Here, we conduct a large-scale exome study to examine whether rare protein-coding variants impact cognitive function in the adult population (n = 485,930). We identify eight genes (ADGRB2, KDM5B, GIGYF1, ANKRD12, SLC8A1, RC3H2, CACNA1A and BCAS3) that are associated with adult cognitive function through rare coding variants with large effects.

Incidence of Aicardi-Goutières syndrome and -related epilepsy in Denmark.

Objective: To estimate the incidence of Aicardi-Goutières syndrome (AGS) and potassium sodium-activated channel subfamily T member 1 (-related epilepsy in Denmark and to characterize the patients diagnosed with AGS and -related epilepsy.

Background: AGS and -related epilepsy are 2 distinct rare genetic disorders. Due to the rarity of AGS and -related epilepsy, the epidemiology remains unclear.

Discovery of Potent, Selective, and Brain-Penetrant Apoptosis Signal-Regulating Kinase 1 (ASK1) Inhibitors that Modulate Brain Inflammation .

Apoptosis signal-regulating kinase 1 (ASK1) is one of the key mediators of the cellular stress response that regulates inflammation and apoptosis. To probe the therapeutic value of modulating this pathway in preclinical models of neurological disease, we further optimized the profile of our previously reported inhibitor . This effort led to the discovery of , a potent (cell IC = 25 nM) and selective ASK1 inhibitor with suitable pharmacokinetic and brain penetration (rat Cl/Cl = 1.

Microglial transcriptome analysis in the rNLS8 mouse model of TDP-43 proteinopathy reveals discrete expression profiles associated with neurodegenerative progression and recovery.

The microglial reaction is a hallmark of neurodegenerative conditions, and elements thereof may exert differential effects on disease progression, either worsening or ameliorating severity. In amyotrophic lateral sclerosis (ALS), a syndrome characterized by cytoplasmic aggregation of TDP-43 protein and atrophy of motor neurons in the cortex and spinal cord, the transcriptomic signatures of microglia during disease progression are incompletely understood. Here, we performed longitudinal RNAseq analysis of cortical and spinal cord microglia from rNLS8 mice, in which doxycycline-regulatable expression of human TDP-43 (hTDP-43) in the cytoplasm of neurons recapitulates many features of ALS.

Proteomic Characterization of the Dynamics of Ischemic Stroke in Mice.

Novel therapies and biomarkers are needed for the treatment of acute ischemic stroke (AIS). This study aimed to provide comprehensive insights into the dynamic proteome changes and underlying molecular mechanisms post-ischemic stroke. TMT-coupled proteomic analysis was conducted on mouse brain cortex tissue from five time points up to 4 weeks poststroke in the distal hypoxic-middle cerebral artery occlusion (DH-MCAO) model.

A Comparison of Revision Rates and Patient-Reported Outcomes for a 2-Level Posterolateral Fusion Augmented With Single Versus 2-Level Transforaminal Lumbar Interbody Fusion.

Study Design: Retrospective, single institution, multisurgeon case control series.

Objective: To determine whether there are differences in reoperation rates or outcomes for patients undergoing 2-level posterolateral fusion (PLF) augmented by a transforaminal lumbar interbody fusion (TLIF) at only one of the levels or at both.

Methods: A total of 416 patients were identified who underwent 2-level PLF with a TLIF at either one of those levels (n = 183) or at both (n = 233) with greater than 1-year follow-up.

Estimating the relative frequency of leukodystrophies and recommendations for carrier screening in the era of next-generation sequencing.

Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies.

MTA2/NuRD Regulates B Cell Development and Cooperates with OCA-B in Controlling the Pre-B to Immature B Cell Transition.

The NuRD complex contains both chromatin remodeling and histone deacetylase activities. Mice lacking the MTA2 subunit of NuRD show developmental defects in pro-B, pre-B, immature B, and marginal zone B cells, and abnormal germinal center B cell differentiation during immune responses. Mta2 inactivation also causes a derepression of Igll1 and VpreB1 genes in pre-B cells.

Hierarchy of clinical manifestations in SAVI N153S and V154M mouse models.

Studies over the past decade have revealed a central role for innate immune sensors in autoimmune and autoinflammatory diseases. cGAS, a cytosolic DNA sensor, detects both foreign and host DNA and generates a second-messenger cGAMP, which in turn binds and activates stimulator of IFN genes (STING), leading to induction of type I interferons and inflammatory cytokines. Recently, gain-of-function mutations in STING have been identified in patients with STING-associated vasculopathy with onset in infancy (SAVI).

Microglia-mediated recovery from ALS-relevant motor neuron degeneration in a mouse model of TDP-43 proteinopathy.

Though motor neurons selectively degenerate in amyotrophic lateral sclerosis, other cell types are likely involved in this disease. We recently generated rNLS8 mice in which human TDP-43 (hTDP-43) pathology could be reversibly induced in neurons and expected that microglia would contribute to neurodegeneration. However, only subtle microglial changes were detected during disease in the spinal cord, despite progressive motor neuron loss; microglia still reacted to inflammatory triggers in these mice.

PDGF-BB Promotes Type I IFN-Dependent Vascular Alterations and Monocyte Recruitment in a Model of Dermal Fibrosis.

Systemic sclerosis (SSc) is a chronic autoimmune disorder that can result in extensive tissue damage in the skin and, in advanced cases, internal organs. Vasculopathy, aberrant immune activation, and tissue fibrosis are three hallmarks of the disease that have been identified, with vasculopathy and aberrant immunity being amongst the earliest events. However, a mechanistic link between these processes has not been established.

Coupling of T cell receptor specificity to natural killer T cell development by bivalent histone H3 methylation.

The fidelity of T cell immunity depends greatly on coupling T cell receptor signaling with specific T cell effector functions. Here, we describe a chromatin-based mechanism that enables integration of TCR specificity into definite T cell lineage commitment. Using natural killer T cells (iNKT cell) as a model of a T cell subset that differentiates in response to specific TCR signaling, we identified a key role of histone H3 lysine 27 trimethylation (H3K27me3) in coupling iNKT cell TCR specificity with the generation of iNKT cells.

Notch simultaneously orchestrates multiple helper T cell programs independently of cytokine signals.

Two models are proposed to explain Notch function during helper T (Th) cell differentiation. One argues that Notch instructs one Th cell fate over the other, whereas the other posits that Notch function is dictated by cytokines. Here we provide a detailed mechanistic study investigating the role of Notch in orchestrating Th cell differentiation.

Histone H3 lysine 9 di-methylation as an epigenetic signature of the interferon response.

Effective antiviral immunity depends on the ability of infected cells or cells triggered with virus-derived nucleic acids to produce type I interferon (IFN), which activates transcription of numerous antiviral genes. However, disproportionately strong or chronic IFN expression is a common cause of inflammatory and autoimmune diseases. We describe an epigenetic mechanism that determines cell type-specific differences in IFN and IFN-stimulated gene (ISG) expression in response to exogenous signals.

Pre-TCR signaling inactivates Notch1 transcription by antagonizing E2A.

Precise control of the timing and magnitude of Notch signaling is essential for the normal development of many tissues, but the feedback loops that regulate Notch are poorly understood. Developing T cells provide an excellent context to address this issue. Notch1 signals initiate T-cell development and increase in intensity during maturation of early T-cell progenitors (ETP) to the DN3 stage.

Notch directly regulates Gata3 expression during T helper 2 cell differentiation.

Notch signaling plays multiple roles to direct diverse decisions regarding cell fate during T cell development. During helper T (Th) cell differentiation, Notch is involved in generating optimal Th2 cell responses. Here, we present data investigating how Notch mediates Th2 cell differentiation.

Notch-dependent T-lineage commitment occurs at extrathymic sites following bone marrow transplantation.

Early T-lineage progenitors (ETPs) arise after colonization of the thymus by multipotent bone marrow progenitors. ETPs likely serve as physiologic progenitors of T-cell development in adult mice, although alternative T-cell differentiation pathways may exist. While we were investigating mechanisms of T-cell reconstitution after bone marrow transplantation (BMT), we found that efficient donor-derived thymopoiesis occurred before the pool of ETPs had been replenished.

Notch signaling is an important regulator of type 2 immunity.

Notch ligands and receptors have been implicated in helper T cell (Th cell) differentiation. Whether Notch signals are involved in differentiation of T helper type 1 (Th1) cells, Th2 cells, or both, however, remains unresolved. To clarify the role of Notch in Th cell differentiation, we generated mice that conditionally inactivate Notch signaling in mature T cells.

Regulation of lymphoid development, differentiation, and function by the Notch pathway.

The Notch pathway is gaining increasing recognition as a key regulator of developmental choices, differentiation, and function throughout the hematolymphoid system. Notch controls the generation of hematopoietic stem cells during embryonic development and may affect their subsequent homeostasis. Commitment to the T cell lineage and subsequent stages of early thymopoiesis is critically regulated by Notch.