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Cognitive or motor impairment is common among individuals with neurofibromatosis type 1 (NF1), an autosomal dominant tumor‐predisposition disorder. As many as 70% of children with NF1 report difficulties with spatial/working memory, attention, executive function, and fine motor movements. In contrast to the utilization of various Nf1 mouse models, here we employ an NF1+/ex42del miniswine model to evaluate the mechanisms and characteristics of these presentations, taking advantage of a large animal species more like human anatomy and physiology. The prefrontal lobe, anterior cingulate, and hippocampus from NF1+/ex42del and wild‐type miniswine were examined longitudinally, revealing abnormalities in mature oligodendrocytes and astrocytes, and microglial activation over time. Imbalances in GABA: Glutamate ratios and GAD67 expression were observed in the hippocampus and motor cortex, supporting the role of disruption in inhibitory neurotransmission in NF1 cognitive impairment and motor dysfunction. Moreover, NF1+/ex42del miniswine demonstrated slower and shorter steps, indicative of a balance‐preserving response commonly observed in NF1 patients, and progressive memory and learning impairments. Collectively, our findings affirm the effectiveness of NF1+/ex42del miniswine as a valuable resource for assessing cognitive and motor impairments associated with NF1, investigating the involvement of specific neural circuits and glia in these processes, and evaluating potential therapeutic interventions. [ABSTRACT FROM AUTHOR]

Regulatory T (T reg) cells developing in the thymus are essential to maintain tolerance and prevent fatal autoimmunity in mice and humans. Expression of the T reg lineage‐defining transcription factor FoxP3 is critically dependent upon T cell receptor (TCR) and interleukin‐2 (IL‐2) signaling. Here, we report that ten‐eleven translocation (Tet) enzymes, which are DNA demethylases, are required early during double‐positive (DP) thymic T cell differentiation and prior to the upregulation of FoxP3 in CD4 single‐positive (SP) thymocytes, to promote Treg differentiation. We show that Tet3 selectively controls the development of CD25− FoxP3lo CD4SP Treg cell precursors in the thymus and is critical for TCR‐dependent IL‐2 production, which drive chromatin remodeling at the FoxP3 locus as well as other Treg‐effector gene loci in an autocrine/paracrine manner. Together, our results demonstrate a novel role for DNA demethylation in regulating the TCR response and promoting Treg cell differentiation. These findings highlight a novel epigenetic pathway to promote the generation of endogenous Treg cells for mitigation of autoimmune responses. Synopsis: This study identifies a temporal requirement for DNA demethylation during Treg cell differentiation from thymic CD4+ T cell and shows a role for Tet3 in modulating IL‐2 production and the development of CD25− FoxP3lo precursors.DNA demethylases are required prior to the upregulation of FoxP3 in CD4 single‐positive thymocytes to promote Treg differentiation.Tet3 selectively controls the development of CD25‐FoxP3lo CD4 Treg cell precursors in the thymus.Tet3 is critical for TCR‐dependent IL‐2 production, which drives genome‐wide chromatin remodeling in an autocrine/paracrine manner. [ABSTRACT FROM AUTHOR]

Hepatobiliary disease causes significant morbidity and mortality in people with cystic fibrosis (CF), yet this problem remains understudied. Previous studies in the newborn CF pig demonstrated decreased bile flow into the small intestine and a microgallbladder with increased luminal mucus and fluid secretion defects. In this study, we examined the intrahepatic bile ducts of the newborn CF pig. We assessed whether our findings from the gallbladder are present elsewhere in the porcine biliary tract and if CF pig cholangiocytes have fluid secretion defects. Immunohistochemistry demonstrated apical CFTR expression in non‐CF pig intrahepatic bile ducts of a variety of sizes; CF pig intrahepatic bile ducts lacked CFTR expression. Assessment of serum markers did not reveal significant signs of hepatobiliary disease except for an elevation in direct bilirubin. Quantitative histology demonstrated that CF pigs had smaller bile ducts that more frequently contained luminal mucus. CF intrahepatic cholangiocyte organoids were smaller and lacked cAMP‐mediated fluid secretion. Together these data suggest that cholangiocyte fluid secretion is decreased in the CF pig, contributing to structural changes in bile ducts and decreased biliary flow. [ABSTRACT FROM AUTHOR]

ABSTRACT: New treatment options are urgently required in the field of chondrosarcoma, particularly of chondrosarcomas with a well‐differentiated hyaline cartilage‐like extracellular matrix (e.g., collagen II and proteoglycan‐rich) phenotype, notoriously resistant to drug penetration, and having potential of progression towards higher grade. We investigated the feasibility of using 5′‐methylschweinfurthin G (MeSG) as a tumor suppressor agent in the Swarm rat chondrosarcoma, an intermediate‐ to high‐grade chondrosarcoma model, having a hyaline cartilage‐like phenotype. Tumor cell culture studies were performed to identify their proliferative and cytotoxicity sensitivity to MeSG. Tumor burden mice were treated with MeSG and analyzed for tumor growth, morphology and regression. The chondrosarcoma tumor cells had a half maximum cytotoxicity concentration (IC50) of 35 nM MeSG; approximately 300‐fold less than freshly isolated rat chondrocytes (IC50 of 11 µM). Multiple injections of MeSG (20 mg/kg, body weight) resulted in reduced/eliminated tumor growth over a 17‐day period in mice, and an 83% reduction (p = 0.023) in tumor mass. Three out of ten MeSG treated mice had complete elimination of tumor. Tumors of treated mice had a decrease in chondrosarcoma cell proliferation (p = 0.012) and an increase in cell death (p = 0.030) compared with tumors of control mice. These findings in an animal model demonstrate the effectiveness of MeSG for treatment of rat chondrosarcomas, and may have the potential use as a therapeutic option for the difficult‐to‐treat intermediate‐to high‐grade hyaline cartilage‐like chondrosarcoma. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1283–1293, 2018. [ABSTRACT FROM AUTHOR]

Sjögren syndrome is an autoimmune disease characterized by targeted destruction of the lacrimal and salivary glands resulting in symptoms of severe ocular and oral dryness. Despite its prevalence, the mechanisms driving autoimmune manifestations are unclear. In patients and in the nonobese diabetic (NOD) mouse model of Sjögren syndrome, lymphocytic infiltrates consist of CD4 and CD8 T cells, although the role of CD8 T cells in disease pathogenesis has been largely unexplored. Here, we evaluated the contribution of CD8 T cells to lacrimal and salivary gland autoimmunity. Within the lacrimal and salivary glands of NOD mice, CD8 T cells were proliferating, expressed an activated phenotype, and produced inflammatory cytokines. Transfer of purified CD8 T cells isolated from the cervical lymph nodes (LNs) of NOD mice into NOD-severe combined immunodeficiency recipients resulted in inflammation of the lacrimal glands, but was not sufficient to cause inflammation of the salivary glands. Lacrimal gland-infiltrating CD8 T cells displayed a cytotoxic phenotype, and epithelial cell damage in the lacrimal glands was observed in recipients of CD8 T cells regardless of the presence of CD4 T cells. Collectively, our results demonstrate that CD8 T cells have a pathogenic role in lacrimal gland autoimmunity. The gland-specific pathogenicity of CD8 T cells makes them a valuable resource to further understand the mechanisms that discriminate lacrimal versus salivary gland autoimmunity and for the development of new therapeutics that target the early stages of disease. [ABSTRACT FROM AUTHOR]

Key Clinical Message Mounier-Kuhn syndrome is a rare clinical disorder characterized by tracheobronchial dilation and recurrent lower respiratory tract infections. While the etiology of the disease remains unknown, histopathological analysis of Mounier-Kuhn airways demonstrates that the disease is, in part, characterized by cellular changes in airway smooth muscle. [ABSTRACT FROM AUTHOR]

Flawed data continue to undermine the reproducibility of scientific publications. First, authors could identify at manuscript submission whether pathology expertise was utilised to generate and interpret pathology data. Second, pathologists who contribute to pathology data, whether as an author or in acknowledgements, must review their data in the final manuscript to validate its content. [Extracted from the article]

Objective: Diet-induced obesity has been shown to alter immune function in mice, but distinguishing the effects of obesity from changes in diet composition is complicated. It was hypothesized that immunological differences would exist between diet-induced obese (DIO) and obese-resistant (OB-Res) mice fed the same high-fat diet (HFD).Methods: BALB/c mice were fed either standard chow or HFD to generate lean or DIO and OB-Res mice, respectively. Resulting mice were analyzed for serum immunologic and metabolic profiles and cellular immune parameters.Results: BALB/c mice on HFD were categorized as DIO or OB-Res, based on body weight versus lean controls. DIO mice were physiologically distinct from OB-Res mice, whose serum insulin, leptin, gastric inhibitory polypeptide, and eotaxin concentrations remained similar to lean controls. DIO mice had increased macrophage(+) crown-like structures in white adipose tissue, although macrophage percentages were unchanged from OB-Res and lean mice. DIO mice also had decreased splenic CD4(+) T cells, elevated serum GM-CSF, and increased splenic CD11c(+) dendritic cells, but impaired dendritic cell stimulatory capacity (P < 0.05 vs. lean controls). These parameters were unaltered in OB-Res mice versus lean controls.Conclusions: Diet-induced obesity results in alterations in immune and metabolic profiles that are distinct from effects caused by HFD alone. [ABSTRACT FROM AUTHOR]

The pancreas is one of the earliest, and most commonly affected, organs in patients with cystic fibrosis ( CF). Studying the pathogenesis of pancreatic disease is limited in CF patients, due to its early clinical onset, co-morbidities and lack of tissue samples from the early phases of disease. In recent years, several new CF animal models have been developed that have advanced our understanding of both CF exocrine and endocrine pancreatic disease. Additionally, these models have helped us to better define the influence of pancreatic lesions on CF disease progression in other organs, such as the gastrointestinal tract and lung. Copyright Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Tracheal cartilage ring structural abnormalities have been reported in cystic fibrosis (CF) mice and pigs. Whether similar findings are present in humans with CF is unknown. We hypothesized that tracheal cartilage ring shape and size would be different in people with CF.Study Design: Tracheal cartilage ring size and shape were measured in adults with (n = 21) and without CF (n = 18).Methods: Ultrasonography was used in human subjects to noninvasively assess tracheal cartilage ring structure in both the sagittal and the transverse planes. Tracheal cartilage ring thickness was also determined from histological sections obtained from newborn non-CF and CF pigs. These values were compared with human data.Results: Human CF tracheas had a greater width and were less circular in shape compared to non-CF subjects. CF tracheal cartilage rings had a greater midline cross-sectional area and were thicker compared to non-CF rings. Maximal tracheal cartilage ring thickness was also greater in both newborn CF pigs and human adults with CF, compared to non-CF controls.Conclusions: Our findings demonstrate that structural differences exist in tracheal cartilage rings in adults with CF. Comparison with newborn CF pig data suggests that some of these changes may be congenital in nature.Level Of Evidence: 3b [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Chronic sinusitis is nearly universal in humans with cystic fibrosis (CF) and is accompanied by sinus hypoplasia (small sinuses). However, whether impaired sinus development is a primary feature of loss of the cystic fibrosis transmembrane conductance regulator (CFTR) or a secondary consequence of chronic infection remains unknown. Our objective was to study the early pathogenesis of sinus disease in CF. Study Design: Animal/basic science research. Methods: Sinus development was studied in a porcine CF model. Results: Porcine sinus epithelia expressed CFTR and exhibited transepithelial anion transport. Disruption of the CFTR gene eliminated both. Sinuses of newborn CF pigs were not infected and showed no evidence of inflammation, yet were hypoplastic at birth. Older CF pigs spontaneously developed sinus disease similar to that seen in humans with CF. Conclusions: These results define a role for CFTR in sinus development and suggest the potential of the CF pig as a genetic model of CF-sinus disease in which to test therapeutic strategies to minimize sinus-related CF morbidity. [ABSTRACT FROM AUTHOR]

T-cell immunoglobulin mucin-1 (Tim-1) is a transmembrane protein postulated to be a key regulator of Th2-type immune responses. This hypothesis is based in part upon genetic studies associating Tim-1 polymorphisms in mice with a bias toward airway hyperrespon-siveness (AHR) and the development of Th2-type CD4+ T cells. Tim-1 expressed by Th2 CD4+ T cells has been proposed to function as a co-stimulatory molecule. Tim-1 is also expressed by B cells, macrophages, and dendritic cells, but its role in responses by these cell types has not been firmly established. Here, we generated Tim-1-deficient mice to determine the role of Tim-1 in a murine model of allergic airway disease that depends on the development and function of Th2 effector cells and results in the generation of AHR. We found antigen-driven recruitment of inflammatory cells into airways is increased in Tim-1-deficient mice relative to WT mice. In addition, we observed increased antigen-specific cytokine production by splenocytes from antigen-sensitized Tim-1-deficient mice relative to those from controls. These data support the conclusion that Tim-1 functions in pathways that suppress recruitment of inflammatory cells into the airways and the generation or activity of CD4+ T cells. [ABSTRACT FROM AUTHOR]

Background: Chronic consumption of ethanol (EtOH) is well recognized to lead to defective innate and adaptive immune responses and increase the severity of pulmonary infections. Our own studies have demonstrated that chronic EtOH consumption decreases CD8 T-cell immunity to influenza virus infections (IAV) leading to severe infections and mortality. Interestingly, antiviral treatment of IAVs has been shown to be compromised in mice and humans that are immuno-deficient. It is known that EtOH can alter the pharmacokinetics of antivirals. Therefore, the effectiveness of influenza antiviral therapy during chronic ethanol consumption remains in question. Methods: BALB/c mice were placed on 18% (w/v) EtOH in their drinking water for 8 weeks. Chronic EtOH consuming and water controls were then treated with 10 mg/kg oseltamivir orally and infected intranasally with influenza virus 4 hours post-oseltamivir treatment. The mice were then treated with oseltamivir twice daily until day 7 postinfection. Influenza disease severity was measured by morbidity and mortality, pulmonary viral titers, and histology. Results: Chronic EtOH consuming mice infected with IAV and treated with oseltamivir have decreased morbidity and mortality, pulmonary viral titers, and pulmonary pathology compared to untreated EtOH mice. Conclusions: Despite the severe immune defect seen in chronic EtOH mice as well as the potential for EtOH to inhibit the conversion of oseltamivir into an active form, treatment with oseltamivir reduces viral shedding as well as disease severity. These data suggest that the combination of a limited adaptive immune response plus the anti-IAV drug oseltamivir is sufficient to curb high mortality and mediate resolution of IAVs in mice chronically consuming ethanol. [ABSTRACT FROM AUTHOR]

Determination of burn severity (i.e. burn depth) is important for effective medical management and treatment. Using a recently described acute burn model, we studied various morphological parameters to detect burn severity. Anaesthetized Sprague–Dawley rats received burns of various severity (0- to14-s contact time) followed by standard resuscitation using intravenous fluids. Biopsies were taken from each site after 5 h, tissues fixed in 10% neutral-buffered formalin, processed and stained with haematoxylin and eosin. Superficial burn changes in the epidermis included early keratinocyte swelling progressing to epidermal thinning and nuclear elongation in deeper burns. Subepidermal vesicle formation generally decreased with deeper burns and typically contained grey foamy fluid. Dermal burns were typified by hyalinized collagen and a lack of detectable individual collagen fibres on a background of grey to pale eosinophilic seroproteinaceous fluid. Intact vascular structures were identified principally deep to the burn area in the collagen. Follicle cell injury was identified by cytoplasmic clearing/swelling and nuclear pyknosis, and these follicular changes were often the deepest evidence of burn injury seen for each time point. Histological scores (epidermal changes) or dermal parameter depths (dermal changes) were regressed on burn contact time. Collagen alteration ( r2 = 0.91) correlated best to burn severity followed by vascular patency ( r2 = 0.82), epidermal changes ( r2 = 0.76), subepidermal vesicle formation ( r2 = 0.74) and follicular cell injury was useful in all but deep burns. This study confirms key morphological parameters can be an important tool for the detection of burn severity in this acute burn model. [ABSTRACT FROM AUTHOR]

Chronic ethanol ingestion leads to immunological alterations of both the innate and adaptive immune systems and is suggested to contribute, in part, toward the increased susceptibility to and severity of community acquired pneumonia. In this pilot study, C57B1/6 mice treated for 4 weeks with 20% ethanol-in-water (w/v) as the only source water, and matched controls were infected with a lethal dose of influenza A/PR/8/34 H1N1 (200 EIU/mouse). At days four and five post-inoculation (PI), the mice were euthanized, lung tissue formalin-fixed and processed for histopathological examination. There was no significant difference at day four, and pulmonary lesions consisted of necrotizing bronchiolitis with perivascular edema and cellular infiltrate that extended into the alveolar septa. By day five PI, lesions in the chronic ethanol treated mice were more widespread and severe. Necrotizing bronchiolitis was present in a larger fraction of the lung lobes and severe neutrophilic infiltrates effaced many airways structures. Lobar consolidation was accentuated by severe alveolar flooding of seroproteinaceous fluid, cellular infiltrate and atelectasis. Two mechanisms of increased pulmonary lesions are suggested by this study, chronic ethanol exposure may i) increase viral titers, or ii) alter the immune system predisposing the lung to increased damage. [ABSTRACT FROM AUTHOR]

Background: Congenital heart defects are the most common birth defects worldwide. Although defective Notch signaling is the major cause of mouse embryonic death from cardiovascular defects, how Notch signaling is regulated during embryonic vasculogenesis and heart development is poorly understood., Methods and Results: Regulator of G protein signaling 6 (RGS6) -/- /Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) VV double mutant mice were developed by crossing RGS6 -/- mice with mice expressing an oxidation-resistant CaMKIIδ (CaMKII VV ), and the resulting embryonic defects/lethality were investigated using E7.5 to E15.5 embryos. While loss of either RGS6 or oxidized CaMKIIδ does not alter embryogenesis, their combined loss causes defective Notch signaling, severe cardiovascular defects, and embryonic lethality (≈E10.5-11.5). Embryos lacking RGS6 and expressing oxidation-resistant CaMKIIδ exhibit reduced myocardial wall thickness, abnormal trabeculation, and arterial specification defects. Double mutants show vascular remodeling defects, including reduced neurovascularization, delayed neural tube maturation, and small dorsal aortae. These striking cardiovascular defects were accompanied by placental and yolk sac defects in angiogenesis, hematopoiesis, and vascular remodeling similar to what is seen with defective Notch1 signaling. Double mutant hearts, embryos, and yolk sacs exhibit profound downregulation of Notch1, Jagged 1, and Notch downstream target genes Hey1, Hey2, and Hey1L as well as impaired Notch1 signaling in embryos/hearts., Conclusions: RGS6 and oxidized CaMKIIδ together function as novel critical upstream modulators of Notch signaling required for normal cardiovascular development and embryo survival. Their combined need indicates that they function in parallel pathways needed for Notch1 signaling in yolk sac, placenta and embryos. Thus, dysregulated embryonic RGS6 expression and oxidative activation of CaMKII may potentially contribute to congenital heart defects., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)