The rockefeller university

Multisystem inflammatory syndrome in children (MIS-C) emerged in April 2020 in communities with high COVID-19 rates. This new condition is heterogenous but resembles Kawasaki disease (KD), a well-known but poorly understood and clinically heterogenous pediatric inflammatory condition for which weak associations have been found with a myriad of viral illnesses. Epidemiological data clearly indicate that SARS-CoV-2 is the trigger for MIS-C, which typically occurs about 1 mo after infection. These findings support the hypothesis of viral triggers for the various forms of classic KD. We further suggest that rare inborn errors of immunity (IEIs) altering the immune response to SARS-CoV-2 may underlie the pathogenesis of MIS-C in some children. The discovery of monogenic IEIs underlying MIS-C would shed light on its pathogenesis, paving the way for a new genetic approach to classic KD, revisited as a heterogeneous collection of IEIs to viruses.

The mitochondrial electron transport chain (ETC) has been an attractive target for cancer therapy due to its essentiality for tumor growth. Krall et al. found that under ETC dysfunction, a decrease in asparagine limits cancer cell proliferation and activates the integrated stress response, creating a therapeutically exploitable metabolic vulnerability.

The human genetic dissection of clinical phenotypes is complicated by genetic heterogeneity. Gene burden approaches that detect genetic signals in case-control studies are underpowered in genetically heterogeneous cohorts. We therefore developed a genome-wide computational method, network-based heterogeneity clustering (NHC), to detect physiological homogeneity in the midst of genetic heterogeneity. Simulation studies showed our method to be capable of systematically converging genes in biological proximity on the background biological interaction network, and capturing gene clusters harboring presumably deleterious variants, in an efficient and unbiased manner. We applied NHC to whole-exome sequencing data from a cohort of 122 individuals with herpes simplex encephalitis (HSE), including 13 individuals with previously published monogenic inborn errors of TLR3-dependent IFN-alpha/beta immunity. The top gene cluster identified by our approach successfully detected and prioritized all causal variants of five TLR3 pathway genes in the 13 previously reported individuals. This approach also suggested candidate variants of three reported genes and four candidate genes from the same pathway in another ten previously unstudied individuals. TLR3 responsiveness was impaired in dermal fibroblasts from four of the five individuals tested, suggesting that the variants detected were causal for HSE. NHC is, therefore, an effective and unbiased approach for unraveling genetic heterogeneity by detecting physiological homogeneity.

Quiescent neural stem cells (NSCs) in the adult mouse ventricular-subventricular zone (V-SVZ) undergo activation to generate neurons and some glia. Here we show that platelet-derived growth factor receptor beta (PDGFR beta) is expressed by adult V-SVZ NSCs that generate olfactory bulb interneurons and glia. Selective deletion of PDGFRb in adult V-SVZ NSCs leads to their release from quiescence, uncovering gliogenic domains for different glial cell types. These domains are also recruited upon injury. We identify an intraventricular oligodendrocyte progenitor derived from NSCs inside the brain ventricles that contacts supraependymal axons. Together, our findings reveal that the adult V-SVZ contains spatial domains for gliogenesis, in addition to those for neurogenesis. These gliogenic NSC domains tend to be quiescent under homeostasis and may contribute to brain plasticity.

Toll-like receptors are essential for animal development and survival, with conserved roles in innate immunity, tissue patterning, and cell behavior. The mechanisms by which Toll receptors signal to the nucleus are well characterized, but how Toll receptors generate rapid, localized signals at the cell membrane to produce acute changes in cell polarity and behavior is not known. We show that Drosophila Toll receptors direct epithelial convergent extension by inducing planar-polarized patterns of Src and PI3-kinase (PI3K) activity. Toll receptors target Src activity to specific sites at themembrane, and Src recruits PI3K to the Toll-2 complex through tyrosine phosphorylation of the Toll-2 cytoplasmic domain. Reducing Src or PI3K activity disrupts planar-polarized myosin assembly, cell intercalation, and convergent extension, whereas constitutive Src activity promotes ectopic PI3K and myosin cortical localization. These results demonstrate that Toll receptors direct cell polarity and behavior by locally mobilizing Src and PI3K activity.

The flexible control of sequential behavior is a fundamental aspect of speech, enabling endless reordering of a limited set of learned vocal elements (syllables or words). Songbirds are phylogenetically distant from humans but share both the capacity for vocal learning and neural circuitry for vocal control that includes direct pallial-brainstem projections. Based on these similarities, we hypothesized that songbirds might likewise be able to learn flexible, moment-by-moment control over vocalizations. Here, we demonstrate that Bengalese finches (Lonchura striata domestica), which sing variable syllable sequences, can learn to rapidly modify the probability of specific sequences (e.g. 'ab-c' versus 'ab-d') in response to arbitrary visual cues. Moreover, once learned, this modulation of sequencing occurs immediately following changes in contextual cues and persists without external reinforcement. Our findings reveal a capacity in songbirds for learned contextual control over syllable sequencing that parallels human cognitive control over syllable sequencing in speech.

Although antiviral antibodies generally confer protective functions, antibodies against dengue virus (DENV) are associated with enhanced disease susceptibility. Antibodies can mediate DENV infection of leukocytes via Fcg receptors, likely contributing to dengue disease pathogenesis. To determine if this mechanism accounts for variable disease severity, we examined Fab and Fc structures of anti-DENV antibodies from patients before and after infection and with variable disease outcomes. Neither antibody titers nor neutralizing activity correlated with disease severity in DENV-infected populations. Rather, DENV infection induced a specific increase in immunoglobulin G1 (IgG1) afucosylation, and the levels of afucosylated IgG1 were predictive of dengue disease severity. Thus, the IgG1 fucosylation status represents a robust prognostic tool for dengue disease, highlighting the key role of the Fc glycan structure in dengue pathogenesis.

Hidradenitis suppurativa (HS) is a chronic, inflammatory, recurrent and debilitating skin disease of the hair follicle unit that typically develops after puberty. The disorder is characterized by comedones, painful inflammatory nodules, abscesses, dermal tunnels and scarring, with a predilection for intertriginous areas of the body (axillae, inguinal and anogenital regions). Recruitment of neutrophils to HS lesion sites may play an essential role in the development of the painful inflammatory nodules and abscesses that characterize the disease. This is a review of the major mediators involved in the recruitment of neutrophils to sites of active inflammation, including bacterial components (endotoxins, exotoxins, capsule fragments, etc.), the complement pathway anaphylatoxins C3a and C5a, tumour necrosis factor-alpha, interleukin (IL)-17, IL-8 (CXCL8), IL-36, IL-1, lipocalin-2, leukotriene B4, platelet-activating factor, kallikreins, matrix metalloproteinases, and myeloperoxidase inhibitors. Pharmacological manipulation of the various pathways involved in the process of neutrophil recruitment and activation could allow for successful control and stabilization of HS lesions and the remission of active, severe flares.

Cancer cells exhibit hyperactive secretory states that maintain cancer cell viability and remodel the tumor microenvironment. However, the oncogenic signals that heighten secretion remain unclear. Here, we show that p53 loss activates prometastatic secretory vesicle biogenesis in the Golgi. p53 loss up-regulates the expression of a Golgi scaffolding protein, progestin and adipoQ receptor 11 (PAQR11), which recruits an adenosine diphosphate ribosylation factor 1-containing protein complex that loads cargos into secretory vesicles. PAQR11-dependent secretion of a protease, PLAU, prevents anoikis and initiates autocrine activation of a PLAU receptor/signal transducer and activator of transcription-3-dependent pathway that up-regulates PAQR11 expression, thereby completing a feedforward loop that amplifies prometastatic effector protein secretion. Pharmacologic inhibition of PLAU receptor impairs the growth and metastasis of p53-deficient cancers. Blockade of PAQR11-dependent secretion inhibits immunosuppressive processes in the tumor microenvironment. Thus, Golgi reprogramming by p53 loss is a key driver of hypersecretion in cancer.