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Taste cues regulate immediate feeding behavior, but their ability to modulate future behavior has been less well studied. Pairing one taste with another can modulate subsequent feeding responses through associative learning, but this re-quires simultaneous exposure to both stimuli. We investigated whether exposure to one taste modulates future responses to other tastes even when they do not overlap in time. Using Drosophila, we found that brief exposure to sugar enhanced future feeding responses, whereas bitter exposure suppressed them. This modulation relies on neural pathways distinct from those that acutely regulate feeding or mediate learning-dependent changes. Sensory neuron activity was required not only during initial taste exposure but also afterward, suggesting that ongoing sensory activity may maintain experience-dependent changes in downstream circuits. Thus, the brain stores a memory of each taste stimulus after it disappears, enabling animals to integrate information as they sequentially sample different taste cues that signal local food quality.

Neuromyelitis optica spectrum disorders (NMOSD) are rare, debilitating autoimmune diseases of the central nervous system. Many NMOSD patients have antibodies to Aquaporin-4 (AQP4). Prior studies show associations of NMOSD with individual Human Leukocyte Antigen (HLA) alleles and with mutations in the complement pathway and potassium channels. HLA allele associations with NMOSD are inconsistent between populations, suggesting complex relationships between the identified alleles and risk of disease. We used a retrospective case-control approach to identify contributing genetic variants in patients who met the diagnostic criteria for NMOSD and their unaffected family members. Potentially deleterious variants identified in NMOSD patients were compared to members of their families who do not have the disease and to existing databases of human genetic variation. HLA sequences from patients from Belgrade, Serbia, were compared to the frequency of HLA haplotypes in the general population in Belgrade. We analyzed exome sequencing on 40 NMOSD patients and identified rare inherited variants in the complement pathway and potassium channel genes. Haplotype analysis further detected two haplotypes, HLA-A*01, B*08, DRB1*03 and HLA-A*01, B*08, C*07, DRB1*03, DQB1*02, which were more prevalent in NMOSD patients than in unaffected individuals. In silico modeling indicates that HLA molecules within these haplotypes are predicted to bind AQP4 at several sites, potentially contributing to the development of autoimmunity. Our results point to possible autoimmune and neurodegenerative mechanisms that cause NMOSD, and can be used to investigate potential NMOSD drug targets.

In simian-human immunodeficiency virus (SHIV)-infected non-human primates, broadly neutralizing antibodies (bNAbs) against the virus appear to stimulate T cell immunity. To determine whether this phenomenon also occurs in humans we measured HIV-1-specific cellular immunity longitudinally in individuals with HIV-1 starting antiviral therapy (ART) with or without adjunctive bNAb 3BNC117 treatment. Using the activation-induced marker (AIM) assay and interferon-gamma release, we observe that frequencies of Pol- and Gag-specific CD8(+) T cells, as well as Gag-induced interferon-gamma responses, are significantly higher among individuals that received adjunctive 3BNC117 compared to ART-alone at 3 and 12 months after starting ART. The observed changes in cellular immunity were directly correlated to pre-treatment 3BNC117-sensitivity. Notably, increased HIV-1-specific immunity is associated with partial or complete ART-free virologic control during treatment interruption for up to 4 years. Our findings suggest that bNAb treatment at the time of ART initiation maintains HIV-1-specific CD8(+) T cell responses that are associated with ART-free virologic control. Broadly neutralising anti-HIV-1 antibody (bNAb) administration in nonhuman primates has been shown to stimulate adaptive T cell-specific immunity, with infection prevention observed. In this work, the authors longitudinally analyse HIV-1 specific cellular immunity in HIV-1- infected individuals starting ART with or without adjunctive bNAb treatment.

Introduction: Generalized pustular psoriasis (GPP) is a rare, severe, clinically heterogeneous disease characterized by flares of widespread, noninfectious, macroscopically visible pustules that occur with or without systemic inflammation, and are associated with significant morbidity and mortality. Historically, GPP has been classified as a variant of psoriasis vulgaris (PV, or plaque psoriasis); however, accumulating evidence indicates that these are distinct conditions, requiring different treatment approaches. Areas covered: In this perspective article we review evidence that supports the classification of GPP as distinct from PV. Expert opinion: The histopathologic and clinical appearance of GPP is distinct from that of PV and fundamental differences exist between the two conditions in terms of genetic causes and expression-related mechanisms of disease development. GPP results from dysregulation of the innate immune system, with disruption of the interleukin (IL)-36 inflammatory pathway, induction of inflammatory keratinocyte responses, and recruitment of neutrophils. PV is driven by the adaptive immune system, with a key role played by IL-17. Considering GPP as a separate disease will enable greater focus on its specific pathogenesis and the needs of patients. Many treatments for PV have insufficient efficacy in GPP and a therapeutic approach developed specifically for GPP might lead to better patient outcomes. PLAIN LANGUAGE SUMMARY Generalized pustular psoriasis (GPP) is a rare disease. During episodes of worsening disease, the immune system attacks the skin. This causes large areas of skin to become red and painful, pus-filled blisters suddenly form. Some people with GPP have a history of another, more common, skin condition called psoriasis vulgaris (PV). People with PV develop patches of scaly, itchy skin. In the past, GPP was classed as a type of PV and treated with the same medicines. However, these medicines do not work well in GPP. Researchers now understand more about what causes GPP and how it differs from PV. GPP can cause medical problems throughout the body, leading to life-threatening complications. This means that people with GPP often need urgent medical treatment in hospitals. People with PV are mostly treated outside of hospitals. Any other medical problems are not usually due to PV itself. Researchers have found several genes that are altered in people with GPP and PV, and they differ between the two diseases. For example, changes in a gene called IL36RN are common in GPP but are not seen in PV. The skin of people with these two diseases also looks different under a microscope. Knowing more about GPP and how it differs from PV will help people with GPP to be diagnosed more quickly. It will also help researchers to develop new medicines specifically for GPP, so people can receive better treatment in the future.

Nerves are a component of the tumor microenvironment contributing to cancer pro-gression, but the role of cells from nerves in facilitating cancer invasion remains poorly understood. Here we show that Schwann cells (SC) activated by cancer cells collectively function as tumor-activated Schwann cell tracks (TAST) that promote cancer cell migration and invasion. Nonmyeli-nating SCs form TASTs and have cell gene expression signatures that correlate with diminished survival in patients with pancreatic ductal adenocarcinoma. In TASTs, dynamic SCs form tracks that serve as cancer pathways and apply forces on cancer cells to enhance cancer motility. These SCs are activated by c-Jun, analogous to their reprogramming during nerve repair. This study reveals a mechanism of cancer cell inva-sion that co-opts a wound repair process and exploits the ability of SCs to collectively organize into tracks. These findings establish a novel paradigm of how cancer cells spread and reveal therapeutic opportunities. SIGNIFICANCE: How the tumor microenvironment participates in pancreatic cancer progression is not fully understood. Here, we show that SCs are activated by cancer cells and collectively organize into tracks that dynamically enable cancer invasion in a c-Jun-dependent manner.

Vaccines targeting HIV-1's gp160 spike protein are stymied by high viral mutation rates and structural chicanery. gp160's membrane-proximal external region (MPER) is the target of naturally arising broadly neutralizing antibodies (bnAbs), yet MPER-based vaccines fail to generate bnAbs. Here, nanodisc-embedded spike protein was investigated by cryo-electron microscopy and molecular-dynamics simulations, revealing spontaneous ectodomain tilting that creates vulnerability for HIV-1. While each MPER protomer radiates centrally towards the three-fold axis contributing to a membrane-associated tripod structure that is occluded in the upright spike, tilting provides access to the opposing MPER. Structures of spike proteins with bound 4E10 bnAb Fabs reveal that the antibody binds exposed MPER, thereby altering MPER dynamics, modifying average ectodomain tilt, and imposing strain on the viral membrane and the spike's transmembrane segments, resulting in the abrogation of membrane fusion and informing future vaccine development. The membrane-proximal external region of HIV-1 spike protein is a broadly neutralizing antibody target. Here, cryo-electron microscopy and molecular dynamics reveal spontaneous ectodomain tilting, a vulnerability exploitable for vaccine design.

IMPORTANCE Bariatric surgery is the most effective treatment for severe obesity; yet it is unclear whether the long-term safety and comparative effectiveness of these operations differ across racial and ethnic groups. OBJECTIVE To compare outcomes of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) across racial and ethnic groups in the National Patient-Centered Clinical Research Network (PCORnet) Bariatric Study. DESIGN, SETTING, AND PARTICIPANTS Thiswas a retrospective, observational, comparative effectiveness cohort study that comprised 25 health care systems in the PCORnet Bariatric Study. Patients were adults and adolescents aged 12 to 79 years who underwent a primary (first nonrevisional) RYGB or SG operation between January 1, 2005, and September 30, 2015, at participating health systems. Patient race and ethnicity included Black, Hispanic, White, other, and unrecorded. Data were analyzed from July 1, 2021, to January 17, 2022. EXPOSURE RYGB or SG. OUTCOMES Percentage total weight loss (%TWL); type 2 diabetes remission, relapse, and change in hemoglobin A1c (HbA1c) level; and postsurgical safety and utilization outcomes (operations, interventions, revisions/conversions, endoscopy, hospitalizations, mortality, 30-day major adverse events) at 1, 3, and 5 years after surgery. RESULTS A total of 36 871 patients (mean [SE] age, 45.0 [11.7] years; 29 746 female patients [81%]) were included in the weight analysis. Patients identified with the following race and ethnic categories: 6891 Black (19%), 8756 Hispanic (24%), 19 645 White (53%), 826 other (2%), and 783 unrecorded (2%). Weight loss and mean reductions in HbA(1c) level were larger for RYGB than SG in all years for Black, Hispanic, and White patients (difference in 5-year weight loss: Black, -7.6%; 95% CI, -8.0 to -7.1; P <.001; Hispanic, -6.2%; 95% CI, -6.6 to -5.9; P <.001; White, -5.9%; 95% CI, -6.3 to -5.7; P <.001; difference in change in year 5 HbA1c level: Black, -0.29; 95% CI, -0.51 to -0.08; P =.009; Hispanic, -0.45; 95% CI, -0.61 to -0.29; P <.001; and White, -0.25; 95% CI, -0.40 to -0.11; P =.001.) The magnitude of these differences was small among racial and ethnic groups (1%-3% of %TWL). Black and Hispanic patients had higher risk of hospitalization when they had RYGB compared with SG (hazard ratio [HR], 1.45; 95% CI, 1.17-1.79; P =.001 and 1.48; 95% CI, 1.22-1.79; P <.001, respectively). Hispanic patients had greater risk of all-cause mortality (HR, 2.41; 95% CI, 1.24-4.70; P =.01) and higher odds of a 30-day major adverse event (odds ratio, 1.92; 95% CI, 1.38-2.68; P <.001) for RYGB compared with SG. There was no interaction between race and ethnicity and operation type for diabetes remission and relapse. CONCLUSIONS AND RELEVANCE Variability of the comparative effectiveness of operations for %TWL and HbA(1c) level across race and ethnicity was clinically small; however, differences in safety and utilization outcomes were clinically and statistically significant for Black and Hispanic patients who had RYGB compared with SG. These findings can inform shared decision-making regarding bariatric operation choice for different racial and ethnic groups of patients.

Preliminary work suggested upregulation of inflammatory pathways in patients with common forms of ichthyosis. However, a comprehensive characterization of skin from various ichthyosis subtypes is unavailable, precluding the development of targeted treatments. Thus, we sought to characterize the immune and barrier profiles of common and subtype-specific skin transcriptomes in a large group of patients with ichthyosis. We performed a global RNA-sequencing analysis in 54 patients with ichthyosis (7 with Netherton syndrome, 13 with epidermolytic ichthyosis, 16 with lamellar ichthyosis, and 18 with congenital ichthyosiform erythroderma) and 40 healthy controls. Differentially expressed genes were defined on the basis of fold changes > 2 and false discovery rate < 0.05 criteria. We found robust and significant T helper (Th) 22/Th17 skewing in all subtypes (e.g., IL-17A/C/F, S100A7/8/9/12; P < 0.001) with modest changes in Th2 pathway, primarily in Netherton syndrome, and Th1 skewing in congenital ichthyosiform erythroderma. Across all subtypes (less evident in epidermolytic ichthyosis), lipid metabolism and barrier junction markers were downregulated (e.g., FA2H, CDH10/ 11/12/2; P < 0.05), whereas epidermal cornification and proliferation measures were upregulated (e.g., SPRR1A/ 1B/2C/2G, EREG; P < 0.05). Our findings suggest that the common ichthyosis variants share aberrations in Th17/ Th22 and barrier function, with minimal Th2 modulation. This may help to elucidate the pathogeneses of these subtypes and inform the development of subtype-specific treatments.

Psoriasis increases the risk of cardiovascular disease (CVD). Biomarkers for cardiovascular (CV) risk stratification in psoriasis are lacking, and the effects of psoriasis biologics on CV risk reduction remain unclear. The goal of this study was to identify biomarkers of CV risk in psoriasis blood that are reduced by ustekinumab. We quantified 276 inflammatory and CV-related serum proteins with Olink's multiplex assay in 10 psoriasis patients (vs. 18 healthy controls) and after 12 weeks of ustekinumab treatment. For each protein down-regulated after treatment, the literature was reviewed for studies assessing the protein's association with CVD. Data were collected from each study to calculate CV risk thresholds for each protein, which were compared with protein levels in psoriasis patients before and after treatment. Our results showed that 43 out of 276 proteins were down-regulated after treatment, 25 of which were initially up-regulated at baseline (vs. controls, all p-values <= 0.1). 8 down-regulated proteins were initially elevated above thresholds associated with enhanced CV risk in the literature (myeloperoxidase, C-X-C motif chemokine 10, E-selectin, interleukin-6, cystatin B, von Willebrand factor, tumor necrosis factor receptor 1 and N-terminal prohormone brain natriuretic peptide). Treatment lowered these proteins to below their risk thresholds, except for IL-6, which was lowered but remained at its risk threshold despite successful psoriasis skin treatment. In summary, 12 weeks of ustekinumab treatment reduced serum proteins present at levels associated with CV risk in psoriasis patients. Further studies can evaluate these proteins as potential ustekinumab-modulated biomarkers of CV risk in psoriasis and the impact of ustekinumab on CV risk reduction.

In a family of random variables, Taylor's law or Taylor's power law of fluctuation scaling is a variance function that gives the variance sigma(2) > 0 of a random variable (rv) X with expectation mu > 0 as a power of mu: sigma(2) = A mu(b) for finite real A > 0, b that are the same for all rvs in the family. Equivalently, TL holds when log sigma(2) = a + b log mu, a = log A, for all rvs in some set. Here we analyze the possible values of the TL exponent b in five families of infinitely divisible two-parameter distributions and show how the values of b depend on the parameters of these distributions. The five families are Tweedie-Bar-Lev-Enis, negative binomial, compound Poisson-geometric, compound geometric-Poisson (or Polya-Aeppli), and gamma distributions. These families arise frequently in empirical data and population models, and they are limit laws of Markov processes that we exhibit in each case.