The rockefeller university

Tumor cell intravasation is essential for metastatic dissemination, but its exact mechanism is incompletely understood. We have previously shown that in breast cancer, the direct and stable association of a tumor cell expressing Mena, a Tie2hi/VEGFhi macrophage, and a vascular endothelial cell, creates an intravasation portal, called a "tumor microenvironment of metastasis" (TMEM) doorway, for tumor cell intravasation, leading to dissemination to distant sites. The density of TMEM doorways, also called TMEM doorway score, is a clinically validated prognostic marker of distant metastasis in breast cancer patients. Although we know that tumor cells utilize TMEM doorway-associated transient vascular openings to intravasate, the precise signaling mechanisms involved in TMEM doorway function are only partially understood. Using two mouse models of breast cancer and an in vitro assay of intravasation, we report that CSF-1 secreted by the TMEM doorway tumor cell stimulates local secretion of VEGF-A from the Tie2hi TMEM doorway macrophage, leading to the dissociation of endothelial junctions between TMEM doorway-associated endothelial cells, supporting tumor cell intravasation. Acute blockade of CSF-1/CSF-1R signaling decreases macrophage VEGF-A secretion as well as TMEM doorway-associated vascular opening, tumor cell trans-endothelial migration, and dissemination. These new insights into signaling events regulating TMEM doorway function should be explored further as treatment strategies for metastatic disease.

ImportanceHealth care workers (HCW) faced chronic stress during the COVID-19 pandemic and were at high risk of illness, death and burnout.ObjectiveTo understand the experiences of and assess the acceptability and usability of the "Stress First Aid" (SFA) intervention for HCWs.DesignWe used a mixed methods approach to conduct: (1) a quantitative post-intervention survey of experiences with the SFA intervention within a cluster randomized controlled trial (cRCT); and (2) a qualitative descriptive analysis. The intervention was rolled out over three waves from March 2021 - October 2022 simultaneously with the sites' COVID-19 response.SettingOur team engaged and recruited eight pairs of hospitals and six pairs of Federally Qualified Health Centers (FQHCs), balanced across region, including nine states, and matched on size, type, and COVID-19 burden.ParticipantsA total of 862 HCWs received the SFA intervention and completed both the pre- and post-intervention surveys (FQHC n = 245 and hospital n = 617). For the qualitative analysis, among HCWs who agreed to be contacted for a post-intervention interview, we purposively sampled a subset of 35 HCWs balanced by site, gender, age, race/ethnicity and HCW type.InterventionSFA is an evidence-informed intervention adapted to mitigate the psychosocial impact of COVID-19 on HCWs through individual peer support actions.Main Outcome(s) and Measure(s)Quantitative measures are binary indicators of agreement with 6 questions about experiences with the SFA intervention. For the qualitative analysis, we utilized a semi-structured interview protocol to provide additional context on experience with SFA and how SFA affects HCW well-being.ResultsBetween 48.2 and 59.4% of HCWs agreed or strongly agreed that they: found SFA helpful (48.2%), felt comfortable supporting colleagues (59.4%), would recommend SFA (51.2%), and would continue to use SFA principles (57.2%). Non-White HCWs (particularly Black HCWs), those in assistant/technician positions and those who reported attending a greater number of booster sessions were more likely to agree with positive statements about SFA experiences.Conclusions and RelevanceGiven the continued resurgence of public health emergencies, its lasting effects on HCWs, and related emerging challenges, we expect there to be a continued need for support of patient-facing HCWs.Clinical trial registrationClinical Trials.gov Number: NCT04723576 Registered on 01/22/2021 Clinicaltrials.govNCT04723576.

Bacterial sigma factors bind RNA polymerase (E) to form holoenzyme (E sigma), conferring promoter specificity to E and playing a key role in transcription bubble formation. sigma N is unique among sigma factors in its structure and functional mechanism, requiring activation by specialized AAA+ ATPases. E sigma N forms an inactive promoter complex where the N-terminal sigma N region I (sigma N-RI) threads through a small DNA bubble. On the opposite side of the DNA, the ATPase engages sigma N-RI within the pore of its hexameric ring. Here, we perform kinetics-guided structural analysis of de novo formed E sigma N initiation complexes and engineer a biochemical assay to measure ATPase-mediated sigma N-RI translocation during promoter melting. We show that the ATPase exerts mechanical action to translocate about 30 residues of sigma N-RI through the DNA bubble, disrupting inhibitory structures of sigma N to allow full transcription bubble formation. A local charge switch of sigma N-RI from positive to negative may help facilitate disengagement of the otherwise processive ATPase, allowing subsequent sigma N disentanglement from the DNA bubble.

Chronic inflammatory skin diseases arise from dysregulated interactions between tissue-resident and infiltrating cells, the complexity of which hinders disease understanding and treatment. To address this, here, we present a single-cell spatiotemporal atlas of murine type 2 skin inflammation using MERFISH and scRNA-seq. Analyzing similar to 430,000 cells during MC903-and oxazolone-induced dermatitis, we identify 39 cell types, including pro-inflammatory fibroblasts that resemble those in human atopic dermatitis. Spatial neighborhood analyses reveal basophils as potent activators of pro-inflammatory fibroblasts, with basophil-derived oncostatin-M (OSM) and IL-4 synergizing fibroblast-mediated feedforward basophil and immune recruitment. While fibroblast-specific deletion of the IL-4R alpha receptor disrupts inflammation in vivo, the addition of pharmacologic gp130 inhibition, a core component of the OSM receptor, results in synergistic reduction of inflammation. Our study establishes a basophil-fibroblast circuitry as a critical regulator of type 2 skin inflammation, redefining basophil biology and positioning fibroblasts as dynamic immune regulators and therapeutic targets in inflammatory skin disease.

The 5th International Symposium on Regulatory Autoantibodies Targeting GPCR (RAB-GPCRs) advanced the understanding of the significant role played by autoantibodies targeting G-protein-coupled receptors (GPCRs) in various human diseases. Once considered passive markers, RAB-GPCRs are now recognized as active modulators of cellular signaling, immune regulation, and inflammation. The symposium highlighted their involvement in multiple prominent pathologies, including autoimmune diseases, cardio-and cerebrovascular diseases, and neuroimmunologic disorders such as myalgic encephalomyelitis/chronic fatigue syndrome and post-COVID-19 syndrome (ME/CFS/PCS), as well as solid organ and hematopoietic stem cell transplantation (SOT/HSCT). Experts from rheumatology, immunology, and neurology presented interdisciplinary discussions on the potential of RAB-GPCRs as biomarkers and therapeutic targets. Advances in screening methods, biomarker identification, and therapeutic strategies were shared, emphasizing their diagnostic potential and application in novel therapeutic interventions. This report summarizes key insights from the symposium, particularly focusing on the modulatory properties of RAB-GPCRs and their relevance in both immune-mediated diseases and other pathologies (e.g., vascular, degenerative) that are traditionally not considered primarily immune-mediated. Ongoing research is expected to further establish these autoantibodies as crucial components in disease modulation and systems biology contexts, offering new opportunities for precision medicine and improved clinical outcomes in immune-related disorders.

Mitonuclear discordance has been observed in several shark species. Female philopatry has often been invoked to explain such discordance but has never been explicitly tested. Here, we focus on the white shark, for which female philopatry has been previously proposed, and produced a chromosome-level genome, high-coverage whole-genome autosomal, and uniparental datasets to investigate mitonuclear discordance. We first reconstructed the historical population demography of the species based on autosomal data. We show that this species once comprised a single panmictic population, which experienced a steady decline until recent times when it fragmented into at least three main autosomal genetic groups. Mitochondrial data depict a strikingly different picture, inconsistent with the spatial distribution of autosomal diversity. Using the demographic scenario established from autosomal data, we performed coalescent and forward simulations to test for the occurrence of female philopatry. Coalescent simulations showed that the model can reproduce the autosomal variability, confirming its robustness. A forward simulation framework was further built to explicitly account for a sex-biased reproduction model and track both autosomal and uniparental markers (Y chromosome and mitochondrial DNA). While our model generates data that are consistent with the observed Y chromosome variation, the mitochondrial pattern is never reproduced even under extreme female philopatry (no female migration), strongly suggesting that demography alone cannot explain the mitonuclear discordance. Our framework could, and perhaps should, be extended to other shark species where philopatry has been suggested. It is possible that the proposed widespread occurrence of female philopatry in sharks should be revisited. Significance The mitonuclear discordance seen in sharks is widely attributed to female philopatry but has never been explicitly tested. Herein, we explore the issue in white sharks, for which we assembled a high-resolution genome and reconstructed the demographic history using resequencing data. We used backward and forward simulations to examine the genetic consequences of sex-specific migration patterns using parameter values derived from the demographic analyses of autosomal data. The mitochondrial variability observed in natural populations was never reproduced in any of the simulations-even under extreme female philopatry, suggesting that other forces have contributed to the discordance. The same approach would benefit other species of shark where female philopatry has previously been assumed based on genetic data.

Hyperactivation of the cystic fibrosis transmembrane conductance regulator (CFTR) contributes to secretory diarrhea, a major cause of pediatric mortality worldwide, and autosomal dominant polycystic kidney disease (ADPKD), the most common inherited cause of end-stage renal disease. Selective CFTR inhibition is a potential therapeutic strategy, with (R)-BPO-27 emerging as a promising candidate. Here, we present a cryo-EM structure of CFTR bound to (R)-BPO-27 at an overall resolution of 2.1 & Aring;. Contrary to the previous hypothesis that it inhibits CFTR current by competition with ATP, we demonstrate that (R)-BPO-27 instead directly occludes the chloride-conducting pore while permitting ATP hydrolysis, thus uncoupling the two activities. Furthermore, we find that inhibitor binding requires some degree of NBD separation, as the inhibition rate inversely correlates with the probability NBD dimerization. These findings clarify the compound's mechanism and provide a molecular basis for optimizing its clinical potential.

Congenital anomalies of the kidneys and urinary tract (CAKUT) are developmental disorders that commonly cause pediatric chronic kidney disease and mortality. We examine here rare coding variants in 248 CAKUT trios and 1742 singleton CAKUT cases and compare them to 22,258 controls. Diagnostic and candidate diagnostic variants are detected in 14.1% of cases. We find a significant enrichment of rare damaging variants in constrained genes expressed during kidney development and in genes associated with other developmental disorders, suggesting phenotype expansion. Consistent with these data, 18% of CAKUT patients with diagnostic variants have neurodevelopmental or cardiac phenotypes. We identify 40 candidate genes, including CELSR1, SSBP2, XPO1, NR6A1, and ARID3A. Two are confirmed as CAKUT genes: ARID3A and NR6A1. This study suggests that many yet-unidentified syndromes would be discoverable with larger cohorts and cross-phenotype analysis, leading to clarification of the genetic and phenotypic spectrum of developmental disorders.

Effective vaccines elicit B cell clonal expansion in germinal centers (GCs) that produce memory B cells and antibody-secreting plasma cells. In mice, memory B cells rarely re-enter GCs upon boosting and instead differentiate into plasma cells. However, mouse circulating memory constitutes only 1%-2% of B cells, compared to 30%-50% in primates. We examine memory and GC B cell responses in rhesus macaques immunized and boosted ipsilaterally or contralaterally with an mRNA vaccine encoding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. The neutralizing activity of antibodies cloned from the memory compartment, as well as the size of the compartment, was independent of the site of boosting. We show that memory B cells enter and undergo iterative expansion in newly developing GCs when boosting is at a site distal to the site of priming. Thus, in primates, high-affinity memory B cells constitute a reservoir that actively participates in further development of immunity irrespective of the anatomical site of vaccine boosting.