Optineurin deficiency contributes to impaired cytokine secretion and neutrophil recruitment in bacteria driven colitis.

Crohn's disease (CD) is associated with delayed neutrophil recruitment and bacterial clearance at sites of acute inflammation as a result of impaired secretion of proinflammatory cytokines by macrophages. To investigate the impaired cytokine secretion, we performed transcriptomic analysis in macrophages and identified a subgroup of CD patients with low expression of the autophagy receptor optineurin (OPTN). Here we clarified the role of OPTN deficiency in macrophage cytokine secretion, models of bacteria driven colitis and peritonitis in mice and zebrafish Salmonella infection. OPTN deficient bone-marrow derived macrophages (BMDM) stimulated with heat-killed E. coli secreted less proinflammatory TNF and IL6 cytokines despite similar gene transcription, which normalised with lysosomal and autophagy inhibitors suggesting that TNF is mistrafficked to lysosomes via bafilomycin A dependent pathways in the absence of OPTN. OPTN deficient mice were more susceptible to Citrobacter colitis and E. coli peritonitis with reduced levels of proinflammatory TNF in serum, diminished neutrophil recruitment to sites of acute inflammation and greater mortality. Optn knockdown zebrafish infected with Salmonella also had higher mortality. OPTN plays a role in acute inflammation and neutrophil recruitment, potentially via defective macrophage proinflammatory cytokine secretion, which suggests that diminished OPTN expression in humans may increase the risk of developing CD

Cell arrest and cell death in mammalian preimplantation development

The causes, modes, biological role and prospective significance of cell death in preimplantation development in humans and other mammals are still poorly understood. Early bovine embryos represent a very attractive experimental model for the investigation of this fundamental and important issue. To obtain reference data on the temporal and spatial occurrence of cell death in early bovine embryogenesis, three-dimensionally preserved embryos of different ages and stages of development up to hatched blastocysts were examined in toto by confocal laser scanning microscopy. In parallel, transcript abundance profiles for selected apoptosis-related genes were analyzed by real-time reverse transcriptase-polymerase chain reaction. Our study documents that in vitro as well as in vivo, the first four cleavage cycles are prone to a high failure rate including different types of permanent cell cycle arrest and subsequent non-apoptotic blastomere death. In vitro produced and in vivo derived blastocysts showed a significant incidence of cell death in the inner cell mass (ICM), but only in part with morphological features of apoptosis. Importantly, transcripts for CASP3, CASP9, CASP8 and FAS/FASLG were not detectable or found at very low abundances. In vitro and in vivo, errors and failures of the first and the next three cleavage divisions frequently cause immediate embryo death or lead to aberrant subsequent development, and are the main source of developmental heterogeneity. A substantial occurrence of cell death in the ICM even in fast developing blastocysts strongly suggests a regular developmentally controlled elimination of cells, while the nature and mechanisms of ICM cell death are unclear. Morphological findings as well as transcript levels measured for important apoptosis-related genes are in conflict with the view that classical caspase-mediated apoptosis is the major cause of cell death in early bovine development

Metabolite profiles of medulloblastoma for rapid and non-invasive detection of molecular disease groups

\ua9 2024 The AuthorsBackground: The malignant childhood brain tumour, medulloblastoma, is classified clinically into molecular groups which guide therapy. DNA-methylation profiling is the current classification ‘gold-standard’, typically delivered 3–4 weeks post-surgery. Pre-surgery non-invasive diagnostics thus offer significant potential to improve early diagnosis and clinical management. Here, we determine tumour metabolite profiles of the four medulloblastoma groups, assess their diagnostic utility using tumour tissue and potential for non-invasive diagnosis using in vivo magnetic resonance spectroscopy (MRS). Methods: Metabolite profiles were acquired by high-resolution magic-angle spinning NMR spectroscopy (MAS) from 86 medulloblastomas (from 59 male and 27 female patients), previously classified by DNA-methylation array (WNT (n = 9), SHH (n = 22), Group3 (n = 21), Group4 (n = 34)); RNA-seq data was available for sixty. Unsupervised class-discovery was performed and a support vector machine (SVM) constructed to assess diagnostic performance. The SVM classifier was adapted to use only metabolites (n = 10) routinely quantified from in vivo MRS data, and re-tested. Glutamate was assessed as a predictor of overall survival. Findings: Group-specific metabolite profiles were identified; tumours clustered with good concordance to their reference molecular group (93%). GABA was only detected in WNT, taurine was low in SHH and lipids were high in Group3. The tissue-based metabolite SVM classifier had a cross-validated accuracy of 89% (100% for WNT) and, adapted to use metabolites routinely quantified in vivo, gave a combined classification accuracy of 90% for SHH, Group3 and Group4. Glutamate predicted survival after incorporating known risk-factors (HR = 3.39, 95% CI 1.4–8.1, p = 0.025). Interpretation: Tissue metabolite profiles characterise medulloblastoma molecular groups. Their combination with machine learning can aid rapid diagnosis from tissue and potentially in vivo. Specific metabolites provide important information; GABA identifying WNT and glutamate conferring poor prognosis. Funding: Children with Cancer UK, Cancer Research UK, Children\u27s Cancer North and a Newcastle University PhD studentship

Growth arrest-specific gene 6 expression in human breast cancer

Growth arrest-specific gene 6 (Gas6), identified in 1995, acts as the ligand to the Axl/Tyro3 family of tyrosine kinase receptors and exerts mitogenic activity when bound to these receptors. Overexpression of the Axl/Tyro3 receptor family has been found in breast, ovarian and lung tumours. Gas6 is upregulated 23-fold by progesterone acting through the progesterone receptor B (PRB). Recently, Gas6 has been shown to be a target for overexpression and amplification in breast cancer. Quantitative real-time PCR analysis was used to determine the levels of Gas6 mRNA expression in 49 primary breast carcinomas. Expression of PRB protein was evaluated immunohistochemically with a commercially available PRB antibody. The results showed a positive association between PRB protein and Gas6 mRNA levels (P=0.04). Gas6 correlated positively with a number of favourable prognostic variables including lymph node negativity (P=0.0002), younger age at diagnosis (P=0.04), smaller size of tumours (P=0.02), low Nottingham prognostic index scores (P=0.03) and low nuclear morphology (P=0.03). This study verifies for the first time the association between PRB and Gas6 in breast cancer tissue

A zebrafish model of inflammatory lymphangiogenesis

Inflammatory bowel disease (IBD) is a disabling chronic inflammatory disease of the gastrointestinal tract. IBD patients have increased intestinal lymphatic vessel density and recent studies have shown that this may contribute to the resolution of IBD. However, the molecular mechanisms involved in IBD-associated lymphangiogenesis are still unclear. In this study, we established a novel inflammatory lymphangiogenesis model in zebrafish larvae involving colitogenic challenge stimulated by exposure to 2,4,6-trinitrobenzenesulfonic acid (TNBS) or dextran sodium sulphate (DSS). Treatment with either TNBS or DSS resulted in vascular endothelial growth factor receptor (Vegfr)-dependent lymphangiogenesis in the zebrafish intestine. Reduction of intestinal inflammation by the administration of the IBD therapeutic, 5-aminosalicylic acid, reduced intestinal lymphatic expansion. Zebrafish macrophages express vascular growth factors vegfaa, vegfc and vegfd and chemical ablation of these cells inhibits intestinal lymphatic expansion, suggesting that the recruitment of macrophages to the intestine upon colitogenic challenge is required for intestinal inflammatory lymphangiogenesis. Importantly, this study highlights the potential of zebrafish as an inflammatory lymphangiogenesis model that can be used to investigate the role and mechanism of lymphangiogenesis in inflammatory diseases such as IBD

Severe Mixed Dyslipidemia in Pediatric Population. Diagnosis and Treatment. About A Case

Objetivo: Dar a conocer una presentación atípica de dislipidemia mixta severa en población pediátrica y su abordaje diagnóstico y terapéutico. Caso Clínico: Escolar femenina de 7 años de edad, quien es referida por presentar suero lactescente, evidenciado al realizarle pruebas de laboratorio. Examen físico: talla, peso e índice de masa corporal en percentil 50, hepatomegalia palpable no dolorosa. Paraclínicos de ingreso: glucemia 114 mg/dl, colesterol: 166 mg/dl y triglicéridos: 1200 mg/ dl. Electroforesis: se evidencia VLDL y quilomicrones. Se hace diagnóstico de hiperlipoproteinemia tipo V, se inicia tratamiento con modificación de estilo de vida y ácidos omega 3, 1500 mg/día. Persisten niveles elevados de triglicéridos y aumenta el colesterol, por lo que se omite el omega 3 y se indica tratamiento con ezetimiba 10 mg y ciprofibrato 50 mg diarios. El estudio genético evidenció una variante intrónica G/C en el intrón 7 para el gen de PPAR?, correlacionándose con un riesgo elevado de hipertrigliceridemia y mutación del exón 4 del gen del receptor de LDL, por lo que se modifica el diagnóstico a dislipidemia mixta con elevación de VLDL, quilomicrones y LDL. La evolución actual ha sido satisfactoria. Conclusión: Las hiperlipidemias primarias son un grupo de patologías con frecuencia variables de acuerdo a los diferentes fenotipos presentes. El diagnóstico diferencial es importante para descartar una causa secundaria. La electroforesis y el estudio genético orientan al diagnóstico, y el tratamiento debe ser individualizado dependiendo de la clínica del paciente, los niveles de lípidos plasmáticos y los factores de riesgos [email protected]@hotmail.comObjective: To present an atypical presentation of severe mixed dyslipidemia in the pediatric population and its diagnostic and therapeutic approach. Case Report: Female 7-year-old is referred because of presenting lactescent serum, evidenced by laboratory tests. Physical exam: height, weight and body mass index in the 50th percentile, painless palpable hepatomegaly. Initial paraclinical: glucose 114 mg/dl, cholesterol 166 mg/dl and triglycerides 1200 mg/dl. Electrophoresis: evidence of VLDL and chylomicrons. Hyperlipoproteinemia type V diagnosis is made; treatment is initiated with lifestyle modification and omega 3 fatty acids, 1500 mg/day. However, given the persistence of high levels of triglycerides and cholesterol, the omega 3 fatty acids is omitted and treatment with ezetimibe 10 mg and ciprofibrate 50 mg daily, is indicated. Genetic studies revealed an intronic variant G/C in intron 7 for gene PPAR?, correlated with a high risk of hypertriglyceridemia, and a mutation of exon 4 of gene LDL receptor; for this reason, the diagnosis is modified to mixed dyslipidemia, with elevated VLDL, LDL and chylomicron. The current evolution has been satisfactory. Conclusions: Primary hyperlipidemia is a group of diseases with variable frequency according to the different phenotypes present. The differential diagnosis is important to exclude a secondary cause. Electrophoresis and genetic study guide the diagnosis. Treatment should be individualized depending on the clinical findings of the patient, plasma lipid levels, and associated risk factors