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Engineered T cells expressing chimeric antigen receptors (CARs) have shown remarkable therapeutic effects on haematological malignancies. However, CART cells are less effective on solid tumours mainly due to their weak persistence, which might be caused by activation-induced cell death (AICD). To overcome this limitation, CART cell with the antigen, Epidermal growth factor receptor variant III (EGFRvIII), targeting was modified to carry the anti-apoptotic molecule B cell lymphoma 2 (Bcl-2), and the final construct was named as EGFRvIII·CART-Bcl2 cells. Compared with the EGFRvIII·CART cells, EGFRvIII·CART-Bcl2 cells revealed higher capacities of proliferation, anti-apoptosis and tumour cell killing in vitro. Moreover, EGFRvIII·CART-Bcl2 cells had a longer persistence rate and exerted better anti-tumour effects than EGFRvIII·CART cells in cervical carcinoma xenograft model. Taken together, our findings suggest that incorporating anti-apoptotic molecules into CART cells may enhance its therapeutic effects against solid tumours. [ABSTRACT FROM AUTHOR]

The amyloid precursor protein (APP) is a key molecular component of Alzheimer's disease (AD) pathogenesis. Proteolytic APP processing generates various cleavage products, including extracellular amyloid beta (Aβ) and the cytoplasmic APP intracellular domain (AICD). Although the role of AICD in the activation of kinase signaling pathways is well established in the context of full-length APP, little is known about intracellular effects of the AICD fragment, particularly within discrete neuronal compartments. Deficits in fast axonal transport (FAT) and axonopathy documented in AD-affected neurons prompted us to evaluate potential axon-autonomous effects of the AICD fragment for the first time. Vesicle motility assays using the isolated squid axoplasm preparation revealed inhibition of FAT by AICD. Biochemical experiments linked this effect to aberrant activation of selected axonal kinases and heightened phosphorylation of the anterograde motor protein conventional kinesin, consistent with precedents showing phosphorylation-dependent regulation of motors proteins powering FAT. Pharmacological inhibitors of these kinases alleviated the AICD inhibitory effect on FAT. Deletion experiments indicated this effect requires a sequence encompassing the NPTY motif in AICD and interacting axonal proteins containing a phosphotyrosine-binding domain. Collectively, these results provide a proof of principle for axon-specific effects of AICD, further suggesting a potential mechanistic framework linking alterations in APP processing, FAT deficits, and axonal pathology in AD. [ABSTRACT FROM AUTHOR]

Killer-cell immunoglobulin-like receptors (KIRs) are mainly expressed on natural killer (NK) cells and are key regulators of innate immune responses. NK cells are the first responders in the face of infection and help promote placentation during pregnancy; the importance of KIRs in these NK-mediated processes is well-established. However, mounting evidence suggests that KIRs also have a prominent and long-lasting effect on the adaptive immune system. Here, we review the evidence for the impact of KIRs on T cell responses with a focus on the clinical significance of this interaction. [ABSTRACT FROM AUTHOR]

Advanced wells play a crucial role in maximizing the efficiency of oil production. To achieve a successful design for advanced wells, several parameters must be considered and evaluated. Uncertainty in these parameters can have a significant impact on the performance assessment of the well in its lifetime. Absolute permeability, relative permeability, and permeability anisotropy are the parameters that determine reservoir permeability and are among the most important design parameters to be considered. This paper aims to assess the performance of advanced wells completed with passive and reactive downhole Flow Control Devices (FCDs) under uncertainty in the reservoir permeability parameters. The assessment is conducted through a case study on a synthetic heavy oil reservoir with a strong water drive. The EclipseSM reservoir simulator is used as a simulation tool and the Latin Hypercube Sampling (LHS) approach is applied as a sampling tool for uncertainty analysis in this study. According to the obtained results, under the presence of uncertainty, advanced wells with Autonomous Inflow Control Device (AICD) and Autonomous Inflow Control Valve (AICV) completions are able to mitigate the risk of water production by 53.20% and 71.12% respectively compared to conventional wells. However, Inflow Control Device (ICD) completion can only reduce the risk by 0.87%.

Abstract Background Leukocyte phytohemagglutinin (PHA-L), derived from the L4 tetramer of PHA, has been frequently employed as a mitogen to induce T lymphocyte proliferation in vitro. The biological application of PHA-L in cancer diagnosis and treatment has gained traction in recent years. However, it has been noted that PHA-L obtained using traditional procedures has a massive amount of impurities or toxic components, which interfere with the activity of PHA-L. Preparation of a monoclonal antibody against active PHA-L is a significant tool for studying PHA-L's function and therapeutic potential. Results We successfully prepared monoclonal antibodies against the active components of PHA-L based on the whole PHA-L protein as an antigen, and found that monoclonal antibody 3C1C6G11 can be employed in western blot, immunofluorescence, and immunohistochemistry detection. Importantly, preliminary result shows that the mAb 3C1C6G11 may prevent PHA-L-induced cell aggregation and AICD (activation-induced cell death). Conclusions The monoclonal antibody mAb 3C1C6G11 prepared in this study can be used as an effective tool for detecting PHA-L active components, investigating PHA-L's function and antineoplastic application.

N‐methyl‐D‐aspartate receptors (NMDARs) are critical for the maturation and plasticity of glutamatergic synapses. In the hippocampus, NMDARs mainly contain GluN2A and/or GluN2B regulatory subunits. The amyloid precursor protein (APP) has emerged as a putative regulator of NMDARs, but the impact of this interaction to their function is largely unknown. By combining patch‐clamp electrophysiology and molecular approaches, we unravel a dual mechanism by which APP controls GluN2B‐NMDARs, depending on the life stage. We show that APP is highly abundant specifically at the postnatal postsynapse. It interacts with GluN2B‐NMDARs, controlling its synaptic content and mediated currents, both in infant mice and primary neuronal cultures. Upon aging, the APP amyloidogenic‐derived C‐terminal fragments, rather than APP full‐length, contribute to aberrant GluN2B‐NMDAR currents. Accordingly, we found that the APP processing is increased upon aging, both in mice and human brain. Interfering with stability or production of the APP intracellular domain normalized the GluN2B‐NMDARs currents. While the first mechanism might be essential for synaptic maturation during development, the latter could contribute to age‐related synaptic impairments. [ABSTRACT FROM AUTHOR]

Context and results: Aromaticity is a fundamental chemical concept that has been widely used in explaining the reactivity, stability, structure, and magnetic properties of many molecules such as conjugated macrocycles, metal heterocyclic compounds, and certain metal clusters. Porphyrinoids (including porphyrin) are of particular interest in terms of diverse aromaticity. Various indices therefore have been used to predict the aromaticity of porphyrin-like macrocycles. However, the reliability of these indices for porphyinoids is always questionable. In order to assess the performance of the indices, we have selected six representative indices to predict the aromaticity of 35 porphyrinoids. The calculated values were then compared with the corresponding results obtained from experiments. Our studies suggest that the theoretical prediction by nucleus independent chemical shifts (NICS), topology of the induced magnetic field (TIMF), anisotropy of the induced current density (AICD), and gauge including magnetically induced current method (GIMIC) are essentially consistent with experimental evidence in all 35 cases and thus are preferred indices. Computational and theoretical techniques: Based on density functional theory, the performance of the NICS, TIMF, AICD, GIMIC, harmonic oscillator model of aromaticity (HOMA), and multicenter bond order (MCBO) indices were evaluated theoretically. Molecular geometries were optimized at the M06-2X/6-311G** level. NMR calculations using GIAO or CGST method were performed at the M06-2X/6-311G** level. The above calculations were carried out using Gaussian16 suite. The TIMF, GIMIC, HOMA, and MCBO indices were obtained using the Multiwfn program. The AICD outputs were visualized using the POV-Ray software. [ABSTRACT FROM AUTHOR]

The amyloid precursor protein (APP) is a key molecular component of Alzheimer’s disease (AD) pathogenesis. Proteolytic APP processing generates various cleavage products, including extracellular amyloid beta (Aβ) and the cytoplasmic APP intracellular domain (AICD). Although the role of AICD in the activation of kinase signaling pathways is well established in the context of full-length APP, little is known about intracellular effects of the AICD fragment, particularly within discrete neuronal compartments. Deficits in fast axonal transport (FAT) and axonopathy documented in AD-affected neurons prompted us to evaluate potential axon-autonomous effects of the AICD fragment for the first time. Vesicle motility assays using the isolated squid axoplasm preparation revealed inhibition of FAT by AICD. Biochemical experiments linked this effect to aberrant activation of selected axonal kinases and heightened phosphorylation of the anterograde motor protein conventional kinesin, consistent with precedents showing phosphorylation-dependent regulation of motors proteins powering FAT. Pharmacological inhibitors of these kinases alleviated the AICD inhibitory effect on FAT. Deletion experiments indicated this effect requires a sequence encompassing the NPTY motif in AICD and interacting axonal proteins containing a phosphotyrosine-binding domain. Collectively, these results provide a proof of principle for axon-specific effects of AICD, further suggesting a potential mechanistic framework linking alterations in APP processing, FAT deficits, and axonal pathology in AD.

Background: Leukocyte phytohemagglutinin (PHA-L), derived from the L4 tetramer of PHA, has been frequently employed as a mitogen to induce T lymphocyte proliferation in vitro. The biological application of PHA-L in cancer diagnosis and treatment has gained traction in recent years. However, it has been noted that PHA-L obtained using traditional procedures has a massive amount of impurities or toxic components, which interfere with the activity of PHA-L. Preparation of a monoclonal antibody against active PHA-L is a significant tool for studying PHA-L's function and therapeutic potential. Results: We successfully prepared monoclonal antibodies against the active components of PHA-L based on the whole PHA-L protein as an antigen, and found that monoclonal antibody 3C1C6G11 can be employed in western blot, immunofluorescence, and immunohistochemistry detection. Importantly, preliminary result shows that the mAb 3C1C6G11 may prevent PHA-L-induced cell aggregation and AICD (activation-induced cell death). Conclusions: The monoclonal antibody mAb 3C1C6G11 prepared in this study can be used as an effective tool for detecting PHA-L active components, investigating PHA-L's function and antineoplastic application. [ABSTRACT FROM AUTHOR]

Simple Summary: Chimeric antigen receptor (CAR) T cell treatment is a promising adoptive cell therapy that utilises CAR-expressing primary T cells to target specific tumour antigens. Since its first approval in 2017, the FDA has approved six CAR T cell therapies for blood cancer treatment. Despite their success in treating B cell malignancies, solid-tumour-directed CAR T cells face multifactorial challenges, often resulting in a lack of anti-tumour response in tumour elimination. The aim of this study was to evaluate the potency of expressing anti-apoptotic gene FLICE-like inhibitory protein p43 (c-FLIPp43) in Her2-CAR T cells to resist activation-induced cell death (AICD). This study confirmed the anti-apoptotic activity of c-FLIPp43. However, the expression of c-FLIPp43 reduced the CAR activity in a Her-2 breast cancer xenograft model relative to the control Her2-CAR T cells. This work provides insight into the role of c-FLIP in T cells and its impact on anti-tumour immunity in CAR T cells. CAR T cell treatment of solid tumours is limited by poor persistence partly due to CD95 ligand (CD95L)-induced apoptosis. Both T cells and cells within the tumour microenvironment (TME) may express CD95L, triggering apoptosis in CD95-receptor-positive CAR T cells. Tonic signalling of CAR T cells may also increase CD95-dependent AICD. Because the intracellular protein c-FLIP protects T cells from AICD, we expressed c-FLIPp43 within a Her-2 targeted CAR cassette and evaluated the potential of c-FLIPp43 through in vitro functional assays and in vivo tumour-bearing xenograft model. cFLIP expression protected against CD95L-induced cell death in the Jurkat T cell lines. However, in primary human CAR T cells containing CAR-CD28 domains, c-FLIPp43 overexpression had minimal additional impact on resistance to CD95L-induded cell death. In vitro cytotoxicity against a breast cancer tumour cell line was not altered by c-FLIPp43 expression, but the expression of c-FLIPp43 in Her2-CAR T cells lowered interferon-γ secretion, without markedly affecting IL-2 levels, and c-FLIPp43-Her2-CAR T cells showed reduced anti-tumour activity in immunodeficient mice with breast cancer. The findings of this study provide a new understanding of the effects of controlling extrinsic apoptosis pathway suppression in CAR T cells, suggesting that c-FLIPp43 expression reduces anti-tumour immunity through the modulation of effector T cell pathways. [ABSTRACT FROM AUTHOR]

Structural analysis of the central 12 residue stretch of Amyloid precursor protein Intracellular Domain (AICD 16-27 : T-S-I-H-H-G-V-V-E-V-D-A) was carried out by NMR and homology modeling. Further, metal and polyphenol interactions were also carried out for these 12 residues stretch, as it contains two critical Histidine residues, which were observed to be perturbed via NMR. A full length 57 residues AICD model was generated via computational methods, to ascertain its overall conformation, as the entire structure was unavailable. An overlay of this AICD entire model with the full length Aβ-42 structure matched well, implying similar properties. Docking studies with metals and polyphenols indicated involvement of the key Histidine residues highlighting their roles towards neurodegeneration and AD pathophysiology.Communicated by Ramaswamy H. Sarma.

Recognising the need for a national approach for the recommended best practice for the follow-up of implanted cardiac rhythm devices to ensure patient safety, this document has been produced by the Cardiac Society of Australia and New Zealand (CSANZ). It draws on accepted practice standards and guidelines of international electrophysiology bodies. It lays out methodology, frequency, and content of follow-up, including remote monitoring; personnel, including physician, allied health, nursing and industry; paediatric and adult congenital heart patients; and special considerations including magnetic resonance imaging scanning, perioperative management, and hazard alerts. [ABSTRACT FROM AUTHOR]

Most of the patients with sleep apnea syndrome (SAS) also known as sleep disordered breathing are not diagnosed before undergoing any cardiac interventional procedure. Many of them can safely undergo outpatient procedure under sedation or anesthesia. Few of them with moderate to severe grade of SAS, who are not optimized medically, may create problem and need special consideration. We managed three such cases in cardiac catheterization laboratory; two of them were not diagnosed before. The periprocedural problems we faced in these patients are narrated in this article along with review of literature. Some suggestions for management of such patients undergoing therapeutic cardiac catheterization are also highlighted. [ABSTRACT FROM AUTHOR]

Background Coronavirus disease (COVID-19) is a systemic illness characterized by raging impact of cytokine storm on multiple organs. This may trigger malignant ventricular arrhythmias and unmask a clinically silent cardiomyopathy. Case summary A 57-year-old gentleman, known case of hyperthyroidism and diabetes, was referred to our emergency department with history of two ventricular tachycardia (VT) episodes requiring direct current cardioversion in last 3 h followed by another episode in our emergency department that was cardioverted. There was no past history of cardiac illness. His 12-lead electrocardiogram (during sinus rhythm) along with screening echocardiography suggested Arrhythmogenic right ventricular cardiomyopathy (ARVC). He was coincidentally found to be COVID-19 positive by reverse transcription-polymerase chain reaction (RT-PCR) as part of our routine screening. However, he had no fever or respiratory complaints. We noted raised systemic inflammatory markers and cardiac troponin T which progressively increased over the next 4 weeks paralleled by an increase in ventricular premature contraction burden and thereafter started decreasing and returned to baseline by 6th week when the patient became COVID-19 negative by RT-PCR. Subsequently, a single-chamber automated implantable cardioverter-defibrillator implantation was done following which there was a transient increase in these biomarkers that subsided spontaneously. The patient is asymptomatic during 6 weeks of follow-up. Discussion COVID-19-associated cytokine surge triggering VT storm and unmasking a clinically silent ARVC has not yet been reported. The case highlights a life-threatening presentation of COVID-19 and indicates a probable link between inflammation and arrhythmogenicity. [ABSTRACT FROM AUTHOR]

Amyloid-β precursor protein (APP) is sequentially cleaved by secretases and generates amyloid-β, the major components in senile plaques in Alzheimer's disease. APP is upregulated in human Alzheimer's disease brains. However, the molecular mechanism of how APP contributes to Alzheimer's disease pathogenesis remains incompletely understood. Here we show that truncated APP C586-695 fragment generated by δ-secretase directly binds to CCAAT/enhancer-binding protein beta (CEBPB), an inflammatory transcription factor, and enhances its transcriptional activity, escalating Alzheimer's disease-related gene expression and pathogenesis. The APP C586-695 fragment, but not full-length APP, strongly associates with CEBPB and elicits its nuclear translocation and augments the transcriptional activities on APP itself, MAPT (microtubule-associated protein tau), δ-secretase and inflammatory cytokine mRNA expression, finally triggering Alzheimer's disease pathology and cognitive disorder in a viral overexpression mouse model. Blockade of δ-secretase cleavage of APP by mutating the cleavage sites reduces its stimulatory effect on CEBPB, alleviating amyloid pathology and cognitive dysfunctions. Clearance of APP C586-695 from 5xFAD mice by antibody administration mitigates Alzheimer's disease pathologies and restores cognitive functions. Thus, in addition to the sequestration of amyloid-β, APP implicates in Alzheimer's disease pathology by activating CEBPB upon δ-secretase cleavage. [ABSTRACT FROM AUTHOR]

Ventricular activation via the specialized His Purkinje system results in synchronous bi-ventricular contraction with an endocardial to epicardial activation wavefront. Biventricular (BiV) pacing for cardiac resynchronization therapy (CRT) often results in a non physiological bi-ventricular activation. Furthermore, LV lead implantation may be challenging due to anatomical constraints. Physiological pacing i.e. Permanent His Bundle pacing (HBP)/Left bundle branch pacing (LBBP) provides an alternative to BiV pacing for these patients. In this report, we present the case of CRT with physiological pacing while minimizing hardware using a dual chamber ICD system.

Ventricular fibrillation can lead to sudden cardiac death. Automatic implantable cardioverter defibrillator (AICD) devices have shown to be highly successful in the termination of these arrhythmias and are a first-line modality of treatment for the prevention of sudden cardiac death. We present the case of a 69-year-old female with a history of paroxysmal atrial fibrillation on anticoagulation with apixaban and rate controlled with metoprolol who presented from home with a chief complaint of hiccups. She had a prior admission to the hospital after she was found to have monomorphic ventricular tachycardia during a nuclear stress test. A cardiac work-up including cardiac catheterization and cardiac magnetic resonance imaging did not show any evidence of significant coronary artery disease or reversible cardiomyopathy. The patient underwent successful placement of a single chamber ICD and was discharged home. Twelve weeks after placement of the AICD, the patient was lifting furniture and experienced sudden onset of hiccups. A chest X-ray showed displacement of the AICD lead from the right ventricular apex to the superior vena cava. The patient underwent lead repositioning with complete resolution of her hiccups. The etiology hiccups was suspected to be secondary to irritation of the right phrenic nerve which travels along the anterolateral border of the superior vena cava. We present the case of hiccups following ICD lead displacement. This serves to highlight a rare complication of ICD displacement that healthcare providers should consider when patients with recently placed ICD devices complain of hiccups. [ABSTRACT FROM AUTHOR]

Background: Cardiac pacing can be challenging after a Fontan operation, and limited data exist regarding strategies to plan these epimyocardial systems while minimizing the number of surgical procedures. Methods: A retrospective review of all our 47 patients (mean age 18 years, standard deviation 9 years) with a Fontan palliation who received an epimyocardial cardiac implantable electronic device (CIED) between 2002 and 2020 with regard to the stability of the epimyocardial lead parameters and the incidence of system revisions. Results: Over the last 18 years, 84 implantations or revisions of the epimyocardial CIED in 47 Fontan patients were performed. Mean age at time of the first implantation was 9.4 (range 0.28–29.3) years. Follow‐up period ranges from 0.11 to 18.2 (mean 7.7, standard deviation 4.2) years. A total of 123 pacing leads were implanted of which 99 are still active. From 2010 triple lead cardiac resynchronization devices were used in 17 patients to better cope with lead problems. The initial pacing threshold of the leads inactivated during this study period proved significantly higher (mean 1.66 V) than in the "all leads" group (mean 1.27 V, p =.0005) or the group of the still active leads (mean 1.17 V, p =.00004). Conclusions: When implanted with a low pacing threshold, the bipolar epimyocardial electrodes show stable and good long‐term results in young patients with a Fontan circulation. Resynchronization pacing systems and the prospective implantation of reserve leads may help to reduce the rate of resternotomies and provide a flexible concept to deal with lead failure. [ABSTRACT FROM AUTHOR]

Background and Purpose: Kaempferol is a natural flavonoid widely investigated in various fields due to its antioxidant, anti-cancer, and anti-inflammatory activities, but few studies have shown its inhibitory effect on T cell activation. This study examined the therapeutic potential of kaempferol in atopic dermatitis by modulating T cell activation.Experimental Approach: Effects of kaempferol on T cell activation and the underlying mechanisms were investigated in Jurkat cells and mouse CD4+ T cells. A model of atopic dermatitis in mice was used to determine its therapeutic potential on T cell-mediated conditions in vivo. Western blots, RT-PCR, pulldown assays and ELISA were used, along with histological analysis of skin.Key Results: Pretreatment with kaempferol reduced CD69 expression and production of inflammatory cytokines including IL-2 from activated Jurkat cells and murine CD4+ T cells without cytotoxicity. Pulldown assays revealed that kaempferol physically binds to MRP-1 in T cells, inhibiting the action of MRP-1. In activated T cells, kaempferol suppressed JNK phosphorylation and the TAK1-IKKα mediated NF-κB pathway. Oral administration of kaempferol to mice showed improved manifestation of atopic dermatitis, a T cell-mediated condition. Western blot results showed that, as in the in vitro studies, decreased phosphorylation of JNK was associated with down-regulated MRP-1 activity in vivo, in the kaempferol-treated mice in the atopic dermatitis model.Conclusion and Implications: Kaempferol regulates T cell activation by inhibiting MRP-1 activity in activated T cells, thus showing protective effects against T cell mediated disease in vivo. [ABSTRACT FROM AUTHOR]

Proteolytic processing of the amyloid precursor protein (APP) releases the APP intracellular domain (AICD) from the membrane. Bound to the APP adaptor protein Fe65 and the lysine acetyltransferase (KAT) Tip60, AICD translocates to the nucleus. Here, the complex forms spherical condensates at sites of endogenous target genes, termed AFT spots (AICD-Fe65-Tip60). We show that loss of Tip60 KAT activity prevents autoacetylation, reduces binding of Fe65 and abolishes Fe65-mediated stabilization of Tip60. Autoacetylation is a prerequisite for AFT spot formation, with KAT-deficient Tip60 retained together with Fe65 in speckles. We identify lysine residues 204 and 701 of Fe65 as acetylation targets of Tip60. We do not detect acetylation of AICD. Mutation of Fe65 K204 and K701 to glutamine, mimicking acetylation-induced charge neutralization, increases the transcriptional activity of Fe65 whereas Tip60 inhibition reduces it. The lysine deacetylase (KDAC) class III Sirt1 deacetylates Fe65 and pharmacological modulation of Sirt1 activity regulates Fe65 transcriptional activity. A second acetylation/deacetylation cycle, conducted by CBP and class I/II KDACs at different lysine residues, regulates stability of Fe65. This is the first report describing a role for acetylation in the regulation of Fe65 transcriptional activity, with Tip60 being the only KAT tested that supports AFT spot formation. [ABSTRACT FROM AUTHOR]

The amyloid precursor protein (APP) intracellular domain (AICD) is a metabolic by-product of APP produced through sequential proteolytic cleavage by α-, β-, and γ-secretases. The interaction between AICD and Fe65 has been reported to impair adult neurogenesis in vivo. However, the exact role of AICD in mediating neural stem cell fate remains unclear. To identify the role of AICD in neuronal proliferation and differentiation, as well as to clarify the molecular mechanisms underlying the role of AICD in neurogenesis, we first generated a mouse model expressing the Rosa26-based AICD transgene. AICD overexpression did not alter the spatiotemporal expression pattern of full-length APP or accumulation of its metabolites. In addition, AICD decreased the newly generated neural progenitor cell (NPC) pool, inhibited the proliferation and differentiation efficiency of NPCs, and increased cell death both in vitro and in vivo. Given that abnormal neurogenesis is often associated with depression-like behavior in adult mice, we conducted a forced swim test and tail suspension test with AICD mice and found a depression-like behavioral phenotype in AICD transgenic mice. Moreover, AICD stimulated FOXO3a transcriptional activation, which in turn negatively regulated AICD. In addition, functional loss of FOXO3a in NPCs derived from the hippocampal dentate gyrus of adult AICD transgenic mice rescued neurogenesis defects. AICD also increased the mRNA expression of FOXO3a target genes related to neurogenesis and cell death. These results suggest that FOXO3a is the functional target of AICD in neurogenesis regulation. Our study reveals the role of AICD in mediating neural stem cell fate to maintain homeostasis during brain development via interaction with FOXO3a. • AICD transgenic mouse model showed that AICD inhibits neuronal proliferation and differentiation in vitro and in vivo in the dentate gyrus of adult hippocampus. • AICD stimulates FOXO3a transcriptional activation and protein expression. • FOXO3a negative regulates AICD transcription activity. • FOXO3a is the functional target of AICD in mediating neurogenesis. [ABSTRACT FROM AUTHOR]

Background and aims Sustained activation of CD4+ T cells plays important roles in the pathogenesis of Crohn's disease [CD]. Under physiologic conditions, activated T cells can be timely eliminated by a process termed activation-induced cell death [AICD], restraining T cell over-activation and preventing immunological destruction. We inquired whether defective AICD might explain CD4+ T cell over-activation in CD and investigated the underlying mechanisms. Methods CD14+ macrophages [Mφ] and CD4+ T cells were isolated from intestinal tissues or peripheral blood of controls and CD patients. An ex vivo evaluation system was employed to simulate AICD and cell apoptosis was measured by flow cytometry. Results CD4+ T cells from CD patients fail to undergo AICD in the ex vivo system. Specifically, proinflammatory type 1 helper T [Th1] and type 17 helper T [Th17] cells, rather than immunosuppressive regulatory T [Treg] cells evade AICD in CD. CD14+ Mφ in the intestinal inflammatory microenvironment of CD promote AICD resistance in CD4+ T cells via a cell-to-cell contact-independent manner. Mechanistically, CD14+ Mφ released exosomes express membrane tumour necrosis factor [TNF] which engages TNFR2 on CD4+ T cells and triggers NF-κB signalling, thereby causing AICD resistance. Importantly, clinically applicable anti-TNF antibodies effectively blocked exosomal membrane TNF-induced CD4+ T cell AICD resistance. Conclusions CD14+ Mφ participate in CD pathogenesis by inducing AICD resistance through release of exosomal membrane TNF to activate the TNFR2/NF-κB pathway in CD4+ T cells. These results present new insights into CD pathogenesis and extend mechanistic understanding of anti-TNF agents. Proposed model CD14+ Mφ in the intestinal microenvironment of CD patients maintain the sustained activation of CD4+ T cells through exosomal membrane TNF to induce apoptosis resistance via TNFR2/NF-κB signalling, which could be effectively blocked by clinically applicable anti-TNF agents. [ABSTRACT FROM AUTHOR]

CD5 is expressed on T cells and a subset of B cells (B1a). It can attenuate TCR signalling and impair CTL activation and is a therapeutic targetable tumour antigen expressed on leukemic T and B cells. However, the potential therapeutic effect of functionally blocking CD5 to increase T cell anti‐tumour activity against tumours (including solid tumours) has not been explored. CD5 knockout mice show increased anti‐tumour immunity: reducing CD5 on CTLs may be therapeutically beneficial to enhance the anti‐tumour response. Here, we show that ex vivo administration of a function‐blocking anti‐CD5 MAb to primary mouse CTLs of both tumour‐naïve mice and mice bearing murine 4T1 breast tumour homografts enhanced their capacity to respond to activation by treatment with anti‐CD3/anti‐CD28 MAbs or 4T1 tumour cell lysates. Furthermore, it enhanced TCR signalling (ERK activation) and increased markers of T cell activation, including proliferation, CD69 levels, IFN‐γ production, apoptosis and Fas receptor and Fas ligand levels. Finally, CD5 function‐blocking MAb treatment enhanced the capacity of CD8+ T cells to kill 4T1‐mouse tumour cells in an ex vivo assay. These data support the potential of blockade of CD5 function to enhance T cell‐mediated anti‐tumour immunity. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a neurodegenerative disorder representing the most common form of dementia. It is biologically characterized by the deposition of extracellular amyloid-β (Aβ) senile plaques and intracellular neurofibrillary tangles, constituted by hyperphosphorylated tau protein. The key protein in AD pathogenesis is the amyloid precursor protein (APP), which is cleaved by secretases to produce several metabolites, including Aβ and APP intracellular domain (AICD). The greatest genetic risk factor associated with AD is represented by the Apolipoprotein E ε4 (APOE ε4) allele. Importantly, all of the above-mentioned molecules that are strictly related to AD pathogenesis have also been described as playing roles in the cell nucleus. Accordingly, evidence suggests that nuclear functions are compromised in AD. Furthermore, modulation of transcription maintains cellular homeostasis, and alterations in transcriptomic profiles have been found in neurodegenerative diseases. This report reviews recent advancements in the AD players-mediated gene expression. Aβ, tau, AICD, and APOE ε4 localize in the nucleus and regulate the transcription of several genes, part of which is involved in AD pathogenesis, thus suggesting that targeting nuclear functions might provide new therapeutic tools for the disease.

Alzheimer’s disease is characterized by intracerebral deposition of β-amyloid (Aβ). While Aβ40 is the most abundant form, neurotoxicity is mainly mediated by Aβ42. Sequential cleavage of amyloid precursor protein (APP) by β- and γ-secretases gives rise to full-length Aβ (Aβ1-x) and N-terminally truncated Aβ′ (Aβ11-x) whereas cleavage by α- and γ-secretases leads to the shorter p3 peptides (Aβ17-x). We uncovered significantly higher ratios of 42- versus 40-ending variants for Aβ and Aβ′ than for p3 secreted by mouse neurons and human induced pluripotent stem cell (iPSC)-derived neurons or produced in a cell-free γ-secretase assay with recombinant APP-CTFs. The 42:40 ratio was highest for Aβ′, followed by Aβ and then p3. Mass spectrometry analysis of APP intracellular domains revealed differential processing of APP-C83, APP-C89, and APP-C99 by γ-secretase already at the ε-cleavage stage. This mechanistic insight could aid in developing substrate-targeted modulators of APP-C99 processing to specifically lower the Aβ42:Aβ40 ratio without compromising γ-secretase function.

Alzheimer's disease (AD) manifests as neuronal loss. On the premise of Grb2 overexpression in AD mouse brain and brain tissues of AD patients, our study primarily focuses on the stability of cytoskeletal proteins in the context of degenerative AD-like conditions. Two predominant molecular features of AD, extracellular accumulation of β-amyloid oligomers and intracellular elevation of amyloid precursor protein intracellular domain levels, have been used to closely inspect the series of signalling events. In their presence, multiple signalling pathways involving ROCK and PAK1 proteins lead to disassembly of the cytoskeleton, and Grb2 partially counterbalances the cytoskeletal loss. Increased Grb2-NOX4 interactions play a preventive role against cytoskeletal disassembly, in turn blocking the activity of nitrogen oxides and decreasing the expression of slingshot homolog 1 (SSH-1) protein, a potent inducer of cytoskeleton disassembly. This study unravels a unique role of Grb2 in protecting the cytoskeletal architecture in AD-like conditions and presents a potential new strategy for controlling neurodegeneration.

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To solve the common problem of bottom water ridges in long horizontal wells for prolonging mining life and improving economic benefits, the adaptive inflow control device(AICD) was used. Based on the fluid simulation software of STAR-CCM+, the oil stabilization and water control performance of AICD was simulated and analyzed. The water-oil pressure drop ratio was used as indicator to measure the water control capacity of AICD. The simulation results show that when the inlet flow of AICD is constant, the water-oil pressure drop ratio is increased with the increasing of inlet number. When the inlet number of AICD is constant, the water-oil pressure drop ratio is decreased after increasing with the increasing of runner width. The optimal AICD structure is with 2 inlets, and the runner width is 0.75 mm. The water-oil pressure drop ratio of the structure can exceed 5, and the sensitivity of the structure to flow, viscosity and density is weak with strongly environmental adaptability. [ABSTRACT FROM AUTHOR]

Abstract Wells equipped with flow control devices are a proven method of improving sweep efficiency by controlling the influx of fluids into the well by the addition of a flow restriction at each completion joint. Autonomous Flow Control Device (AFCD) technology has recently achieved the milestone of being approved for full field, commercial application to reduce (1) gas influx in light oil reservoirs and (2) water production in heavy oil reservoirs. Autonomous Flow Control Completions (AFCC) are frequently designed using steady-state well production simulators. The more realistic approach of using a dynamic, reservoir simulator often reduces the exaggerated, single well, production improvement by allowing the reservoir's flow dynamics to be understood in the context of the total field recovery and reservoir's uncertainty. The modelling of AFCCs, as currently implemented in reservoir simulators, is in an early stage of development and requires further improvement. AFCC modelling options in a dynamic, reservoir simulator are discussed in this paper. New workflows for AFCC single-phase performance parametrization with a more reliable, physically realistic model of their performance are presented. It is shown how reservoir simulation of an Advanced Well Completion (AWC) containing ICDs and AICDs can be used to evaluate the control of water production in a heavy oil field. The performance of multiple AWC designs is compared for a range of reservoir simulation models that illustrate various production challenges. New comparison methods are introduced that provide a fundamental understanding of their differences. An oil/water flow modelling workflow for reservoir and well engineering studies for the selection of the optimal (A)FCD completion is provided. Our finding aid engineers to reliably model, and evaluate the "added value", of AFCC technology on a case-by-case basis. [ABSTRACT FROM AUTHOR]

The Amyloid Precursor Protein (APP) has been extensively studied for its role as the precursor of the β-amyloid protein (Aβ) in Alzheimer’s disease (AD). However, our understanding of the normal function of APP is still patchy. Emerging evidence indicates that a dysfunction in APP trafficking and degradation can be responsible for neuronal deficits and progressive degeneration in humans. We recently reported that the Y682 mutation in the 682YENPTY687 domain of APP affects its binding to specific adaptor proteins and leads to its anomalous trafficking, to defects in the autophagy machinery and to neuronal degeneration. In order to identify adaptors that influence APP function, we performed pull-down experiments followed by quantitative mass spectrometry (MS) on hippocampal tissue extracts of three month-old mice incubated with either the 682YENPTY687 peptide, its mutated form, 682GENPTY687 or its phosphorylated form, 682pYENPTY687. Our experiments resulted in the identification of two proteins involved in APP internalization and trafficking: Clathrin heavy chain (hc) and its Adaptor Protein 2 (AP-2). Overall our results consolidate and refine the importance of Y682 in APP normal functions from an animal model of premature aging and dementia. Additionally, they open the perspective to consider Clathrin hc and AP-2 as potential targets for the design and development of new therapeutic strategies.

Neurogenesis impairment starting from early developmental stages is a key determinant of intellectual disability in Down syndrome (DS). Previous evidence provided a causal relationship between neurogenesis impairment and malfunctioning of the mitogenic Sonic Hedgehog (Shh) pathway. In particular, excessive levels of AICD (amyloid precursor protein intracellular domain), a cleavage product of the trisomic gene APP (amyloid precursor protein) up-regulate transcription of Ptch1 (Patched1), the Shh receptor that keeps the pathway repressed. Since AICD results from APP cleavage by γ-secretase, the goal of the current study was to establish whether treatment with a γ-secretase inhibitor normalizes AICD levels and restores neurogenesis in trisomic neural precursor cells. We found that treatment with a selective γ-secretase inhibitor (ELND006; ELN) restores proliferation in neurospheres derived from the subventricular zone (SVZ) of the Ts65Dn mouse model of DS. This effect was accompanied by reduction of AICD and Ptch1 levels and was prevented by inhibition of the Shh pathway with cyclopamine. Treatment of Ts65Dn mice with ELN in the postnatal period P3–P15 restored neurogenesis in the SVZ and hippocampus, hippocampal granule cell number and synapse development, indicating a positive impact of treatment on brain development. In addition, in the hippocampus of treated Ts65Dn mice there was a reduction in the expression levels of various genes that are transcriptionally regulated by AICD, including APP, its origin substrate. Inhibitors of γ-secretase are currently envisaged as tools for the cure of Alzheimer's disease because they lower βamyloid levels. Current results provide novel evidence that γ-secretase inhibitors may represent a strategy for the rescue of neurogenesis defects in DS.

Sequential cleavage of the amyloid-β protein precursor (AβPP) by BACE1 (β-secretase) followed by theγ-secretase complex, is strongly implicated in Alzheimer's disease (AD) but the initial cellular responses to these cleavage events are not fully defined. β-secretase-mediated AβPP processing yields an extracellular domain (sAβPPβ) and a C-terminal fragment of AβPP of 99 amino acids (C99). Subsequent cleavage by γ-secretase produces amyloid-β (Aβ) and an AβPP intracellular domain (AICD). A cellular screen based on the generation of AICD from an AβPP-Gal4 fusion protein was adapted by introducing familial AD (FAD) mutations into the AβPP sequence and linking the assay to Gal4-UAS driven luciferase and GFP expression, to identify responses immediately downstream of AβPP processing in neurons with a focus on the transcription factor Foxo3a which has been implicated in neurodegeneration. The K670N/M671L, E682K, E693G, and V717I FAD mutations and the A673T protective mutation, were introduced into the AβPP sequence by site directed mutagenesis. When expressed in mouse cortical neurons, AβPP-Gal4-UAS driven luciferase and GFP expression was substantially reduced by γ-secretase inhibitors, lowered by β-secretase inhibitors, and enhanced by α-secretase inhibitors suggesting that AICD is a product of the βγ-secretase pathway. AβPP-Gal4-UAS driven GFP expression was exploited to identify individual neurons undergoing amyloidogenic AβPP processing, revealing increased nuclear localization of Foxo3a and enhanced Foxo3a-mediated transcription downstream of AICD production. Foxo3a translocation was not driven by AICD directly but correlated with reduced Akt phosphorylation. Collectively this suggests that βγ-secretase-mediated AβPP processing couples to Foxo3a which could be an early neuronal signaling response in AD. [ABSTRACT FROM AUTHOR]