ResearchPad - Cell Biology https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Intelligent classification of platelet aggregates by agonist type]]> https://www.researchpad.co/product?articleinfo=N05619c97-c4f3-4d90-8c08-4c8b3892035d

Platelets are anucleate cells in blood whose principal function is to stop bleeding by forming aggregates for hemostatic reactions. In addition to their participation in physiological hemostasis, platelet aggregates are also involved in pathological thrombosis and play an important role in inflammation, atherosclerosis, and cancer metastasis. The aggregation of platelets is elicited by various agonists, but these platelet aggregates have long been considered indistinguishable and impossible to classify. Here we present an intelligent method for classifying them by agonist type. It is based on a convolutional neural network trained by high-throughput imaging flow cytometry of blood cells to identify and differentiate subtle yet appreciable morphological features of platelet aggregates activated by different types of agonists. The method is a powerful tool for studying the underlying mechanism of platelet aggregation and is expected to open a window on an entirely new class of clinical diagnostics, pharmacometrics, and therapeutics.

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<![CDATA[Extending thermotolerance to tomato seedlings by inoculation with SA1 isolate of Bacillus cereus and comparison with exogenous humic acid application]]> https://www.researchpad.co/product?articleinfo=N5b151d82-6b14-4a7f-beb8-82f649a56498

Heat stress is one of the major abiotic stresses that impair plant growth and crop productivity. Plant growth-promoting endophytic bacteria (PGPEB) and humic acid (HA) are used as bio-stimulants and ecofriendly approaches to improve agriculture crop production and counteract the negative effects of heat stress. Current study aimed to analyze the effect of thermotolerant SA1 an isolate of Bacillus cereus and HA on tomato seedlings. The results showed that combine application of SA1+HA significantly improved the biomass and chlorophyll fluorescence of tomato plants under normal and heat stress conditions. Heat stress increased abscisic acid (ABA) and reduced salicylic acid (SA) content; however, combined application of SA1+HA markedly reduced ABA and increased SA. Antioxidant enzymes activities revealed that SA1 and HA treated plants exhibited increased levels of ascorbate peroxidase (APX), superoxide dismutase (SOD), and reduced glutathione (GSH). In addition, heat stress markedly reduced the amino acid contents; however, the amino acids were increased with co-application of SA1+HA. Similarly, inductively-coupled plasma mass-spectrometry results showed that plants treated with SA1+HA exhibited significantly higher iron (Fe+), phosphorus (P), and potassium (K+) uptake during heat stress. Heat stress increased the relative expression of SlWRKY33b and autophagy-related (SlATG5) genes, whereas co-application of SA1+HA augmented the heat stress response and reduced SlWRKY33b and SlATG5 expression. The heat stress-responsive transcription factor (SlHsfA1a) and high-affinity potassium transporter (SlHKT1) were upregulated in SA1+HA-treated plants. In conclusion, current findings suggest that co-application with SA1+HA can be used for the mitigation of heat stress damage in tomato plants and can be commercialized as a biofertilizer.

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<![CDATA[Extensive multilineage analysis in patients with mixed chimerism after allogeneic transplantation for sickle cell disease: insight into hematopoiesis and engraftment thresholds for gene therapy]]> https://www.researchpad.co/product?articleinfo=N45d881d7-7b5d-4145-9a50-5e210d91e755

Although studies of mixed chimerism following hematopoietic stem cell transplantation in patients with sickle cell disease (SCD) may provide insights into the engraftment needed to correct the disease and into immunological reconstitution, an extensive multilineage analysis is lacking. We analyzed chimerism simultaneously in peripheral erythroid and granulomonocytic precursors/progenitors, highly purified B and T lymphocytes, monocytes, granulocytes and red blood cells (RBC). Thirty-four patients with mixed chimerism and ≥12 months of follow-up were included. A selective advantage of donor RBC and their progenitors/precursors led to full chimerism in mature RBC (despite partial engraftment of other lineages), and resulted in the clinical control of the disease. Six patients with donor chimerism <50% had hemolysis (reticulocytosis) and higher HbS than their donor. Four of them had donor chimerism <30%, including a patient with AA donor (hemoglobin >10 g/dL) and three with AS donors (hemoglobin <10 g/dL). However, only one vaso-occlusive crisis occurred with 68.7% HbS. Except in the patients with the lowest chimerism, the donor engraftment was lower for T cells than for the other lineages. In a context of mixed chimerism after hematopoietic stem cell transplantation for SCD, myeloid (rather than T cell) engraftment was the key efficacy criterion. Results show that myeloid chimerism as low as 30% was sufficient to prevent a vaso-occlusive crisis in transplants from an AA donor but not constantly from an AS donor. However, the correction of hemolysis requires higher donor chimerism levels (i.e. ≥50%) in both AA and AS recipients. In the future, this group of patients may need a different therapeutic approach.

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<![CDATA[Enhanced genome editing in human iPSCs with CRISPR-CAS9 by co-targeting ATP1a1]]> https://www.researchpad.co/product?articleinfo=N15f2ecb1-82df-41f3-9520-a4bd60a5f2fe

Genome editing in human induced pluripotent stem cells (iPSCs) provides the potential for disease modeling and cell therapy. By generating iPSCs with specific mutations, researchers can differentiate the modified cells to their lineage of interest for further investigation. However, the low efficiency of targeting in iPSCs has hampered the application of genome editing. In this study we used a CRISPR-Cas9 system that introduces a specific point substitution into the sequence of the Na+/K+-ATPase subunit ATP1A1. The introduced mutation confers resistance to cardiac glycosides, which can then be used to select successfully targeted cells. Using this system, we introduced different formats of donor DNA for homology-directed repair (HDR), including single-strand DNAs, double-strand DNAs, and plasmid donors. We achieved a 35-fold increase in HDR when using plasmid donor with a 400 bp repair template. We further co-targeted ATP1A1 and a second locus of interest to determine the enrichment of mutagenesis after cardiac glycoside selection. Through this approach, INDEL rate was increased after cardiac glycoside treatment, while HDR enrichment was only observed at certain loci. Collectively, these results suggest that a plasmid donor with a 400 bp repair template is an optimal donor DNA for targeted substitution and co-targeting ATP1A1 with the second locus enriches for mutagenesis events through cardiac glycoside selection in human iPSCs.

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<![CDATA[The GAR domain integrates functions that are necessary for the proper localization of fibrillarin (FBL) inside eukaryotic cells]]> https://www.researchpad.co/product?articleinfo=N7b58627b-d58f-4103-8a4f-5386839b85f8

Fibrillarin (FBL) is an essential nucleolar protein that participates in pre-rRNA methylation and processing. The methyltransferase domain of FBL is an example of an extremely well-conserved protein domain in which the amino acid sequence was not substantially modified during the evolution from Archaea to Eukaryota. An additional N-terminal glycine–arginine-rich (GAR) domain is present in the FBL of eukaryotes. Here, we demonstrate that the GAR domain is involved in FBL functioning and integrates the functions of the nuclear localization signal and the nucleolar localization signal (NoLS). The methylation of the arginine residues in the GAR domain is necessary for nuclear import but decreases the efficiency of nucleolar retention via the NoLS. The presented data indicate that the GAR domain can be considered an evolutionary innovation that integrates several functional activities and thereby adapts FBL to the highly compartmentalized content of the eukaryotic cell.

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<![CDATA[Protein phosphatase 1 activity controls a balance between collective and single cell modes of migration]]> https://www.researchpad.co/product?articleinfo=Neec4725b-f287-45ea-98b2-be458703a041

Collective cell migration is central to many developmental and pathological processes. However, the mechanisms that keep cell collectives together and coordinate movement of multiple cells are poorly understood. Using the Drosophila border cell migration model, we find that Protein phosphatase 1 (Pp1) activity controls collective cell cohesion and migration. Inhibition of Pp1 causes border cells to round up, dissociate, and move as single cells with altered motility. We present evidence that Pp1 promotes proper levels of cadherin-catenin complex proteins at cell-cell junctions within the cluster to keep border cells together. Pp1 further restricts actomyosin contractility to the cluster periphery rather than at individual internal border cell contacts. We show that the myosin phosphatase Pp1 complex, which inhibits non-muscle myosin-II (Myo-II) activity, coordinates border cell shape and cluster cohesion. Given the high conservation of Pp1 complexes, this study identifies Pp1 as a major regulator of collective versus single cell migration.

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<![CDATA[Control of brown adipose tissue adaptation to nutrient stress by the activin receptor ALK7]]> https://www.researchpad.co/product?articleinfo=N8da7d9e7-5767-4b2e-be84-f4c3ee8d6aa6

Adaptation to nutrient availability is crucial for survival. Upon nutritional stress, such as during prolonged fasting or cold exposure, organisms need to balance the feeding of tissues and the maintenance of body temperature. The mechanisms that regulate the adaptation of brown adipose tissue (BAT), a key organ for non-shivering thermogenesis, to variations in nutritional state are not known. Here we report that specific deletion of the activin receptor ALK7 in BAT resulted in fasting-induced hypothermia due to exaggerated catabolic activity in brown adipocytes. After overnight fasting, BAT lacking ALK7 showed increased expression of genes responsive to nutrient stress, including the upstream regulator KLF15, aminoacid catabolizing enzymes, notably proline dehydrogenase (POX), and adipose triglyceride lipase (ATGL), as well as markedly reduced lipid droplet size. In agreement with this, ligand stimulation of ALK7 suppressed POX and KLF15 expression in both mouse and human brown adipocytes. Treatment of mutant mice with the glucocorticoid receptor antagonist RU486 restored KLF15 and POX expression levels in mutant BAT, suggesting that loss of BAT ALK7 results in excessive activation of glucocorticoid signaling upon fasting. These results reveal a novel signaling pathway downstream of ALK7 which regulates the adaptation of BAT to nutrient availability by limiting nutrient stress-induced overactivation of catabolic responses in brown adipocytes.

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<![CDATA[DASC, a sensitive classifier for measuring discrete early stages in clathrin-mediated endocytosis]]> https://www.researchpad.co/product?articleinfo=Nb7f2c43d-5cad-4a91-87ae-193be22049b5

Clathrin-mediated endocytosis (CME) in mammalian cells is driven by resilient machinery that includes >70 endocytic accessory proteins (EAP). Accordingly, perturbation of individual EAPs often results in minor effects on biochemical measurements of CME, thus providing inconclusive/misleading information regarding EAP function. Live-cell imaging can detect earlier roles of EAPs preceding cargo internalization; however, this approach has been limited because unambiguously distinguishing abortive coats (ACs) from bona fide clathrin-coated pits (CCPs) is required but unaccomplished. Here, we develop a thermodynamics-inspired method, “disassembly asymmetry score classification (DASC)”, that resolves ACs from CCPs based on single channel fluorescent movies. After extensive verification, we use DASC-resolved ACs and CCPs to quantify CME progression in 11 EAP knockdown conditions. We show that DASC is a sensitive detector of phenotypic variation in CCP dynamics that is uncorrelated to the variation in biochemical measurements of CME. Thus, DASC is an essential tool for uncovering EAP function.

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<![CDATA[ERK3/MAPK6 controls IL-8 production and chemotaxis]]> https://www.researchpad.co/product?articleinfo=N1d87523f-4396-4868-b840-82907e4699ce

ERK3 is a ubiquitously expressed member of the atypical mitogen activated protein kinases (MAPKs) and the physiological significance of its short half-life remains unclear. By employing gastrointestinal 3D organoids, we detect that ERK3 protein levels steadily decrease during epithelial differentiation. ERK3 is not required for 3D growth of human gastric epithelium. However, ERK3 is stabilized and activated in tumorigenic cells, but deteriorates over time in primary cells in response to lipopolysaccharide (LPS). ERK3 is necessary for production of several cellular factors including interleukin-8 (IL-8), in both, normal and tumorigenic cells. Particularly, ERK3 is critical for AP-1 signaling through its interaction and regulation of c-Jun protein. The secretome of ERK3-deficient cells is defective in chemotaxis of neutrophils and monocytes both in vitro and in vivo. Further, knockdown of ERK3 reduces metastatic potential of invasive breast cancer cells. We unveil an ERK3-mediated regulation of IL-8 and epithelial secretome for chemotaxis.

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<![CDATA[The axonal actin-spectrin lattice acts as a tension buffering shock absorber]]> https://www.researchpad.co/product?articleinfo=N838190b0-8c6d-4999-ac14-49d8d75193a3

Axons span extreme distances and are subject to significant stretch deformations during limb movements or sudden head movements, especially during impacts. Yet, axon biomechanics, and its relation to the ultrastructure that allows axons to withstand mechanical stress, is poorly understood. Using a custom developed force apparatus, we demonstrate that chick dorsal root ganglion axons exhibit a tension buffering or strain-softening response, where its steady state elastic modulus decreases with increasing strain. We then explore the contributions from the various cytoskeletal components of the axon to show that the recently discovered membrane-associated actin-spectrin scaffold plays a prominent mechanical role. Finally, using a theoretical model, we argue that the actin-spectrin skeleton acts as an axonal tension buffer by reversibly unfolding repeat domains of the spectrin tetramers to release excess mechanical stress. Our results revise the current viewpoint that microtubules and their associated proteins are the only significant load-bearing elements in axons.

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<![CDATA[Exosomes derived from M0, M1 and M2 macrophages exert distinct influences on the proliferation and differentiation of mesenchymal stem cells]]> https://www.researchpad.co/product?articleinfo=Nd25dd209-d5db-42df-996c-b4d1c15cb318

Background

Different phenotypes of macrophages (M0, M1 and M2 Mφs) have been demonstrated to play distinct roles in regulating mesenchymal stem cells in various in vitro and in vivo systems. Our previous study also found that cell-conditioned medium (CM) derived from M1 Mφs supported the proliferation and adipogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs), whereas CM derived from either M0 or M2 Mφs showed an enhanced effect on cell osteogenic differentiation. However, the underlying mechanism remains incompletely elucidated. Exosomes, as key components of Mφ-derived CM, have received increasing attention. Therefore, it is possible that exosomes may modulate the effect of Mφ-derived CM on the property of BMMSCs. This hypothesis was tested in the present study.

Methods

In this study, RAW264.7 cells were induced toward M1 or M2 polarization with different cytokines, and exosomes were isolated from the unpolarized (M0) and polarized (M1 and M2) Mφs. Mouse BMMSCs were then cultured with normal complete medium or inductive medium supplemented with M0-Exos, M1-Exos or M2-Exos. Finally, the proliferation ability and the osteogenic, adipogenic and chondrogenic differentiation capacity of the BMMSCs were measured and analyzed.

Results

We found that only the medium containing M1-Exos, rather than M0-Exos or M2-Exos, supported cell proliferation and osteogenic and adipogenic differentiation. This was inconsistent with CM-based incubation. In addition, all three types of exosomes had a suppressive effect on chondrogenic differentiation.

Conclusion

Although our data demonstrated that exosomes and CM derived from the same phenotype of Mφs didn’t exert exactly the same cellular influences on the cocultured stem cells, it still confirmed the hypothesis that exosomes are key regulators during the modulation effect of Mφ-derived CM on BMMSC property.

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<![CDATA[PI3K activation prevents Aβ42-induced synapse loss and favors insoluble amyloid deposit formation]]> https://www.researchpad.co/product?articleinfo=N1a1f964a-220b-4bd1-ab57-60895576f2c7

Excess of Aβ42 peptide is considered a hallmark of the disease. Here we express the human Aβ42 peptide to assay the neuroprotective effects of PI3K in adult Drosophila melanogaster. The neuronal expression of the human peptide elicits progressive toxicity in the adult fly. The pathological traits include reduced axonal transport, synapse loss, defective climbing ability and olfactory perception, as well as lifespan reduction. The Aβ42-dependent synapse decay does not involve transcriptional changes in the core synaptic protein encoding genes bruchpilot, liprin and synaptobrevin. All toxicity features, however, are suppressed by the coexpression of PI3K. Moreover, PI3K activation induces a significant increase of 6E10 and thioflavin-positive amyloid deposits. Mechanistically, we suggest that Aβ42-Ser26 could be a candidate residue for direct or indirect phosphorylation by PI3K. Along with these in vivo experiments, we further analyze Aβ42 toxicity and its suppression by PI3K activation in in vitro assays with SH-SY5Y human neuroblastoma cell cultures, where Aβ42 aggregation into large insoluble deposits is reproduced. Finally, we show that the Aβ42 toxicity syndrome includes the transcriptional shut down of PI3K expression. Taken together, these results uncover a potential novel pharmacological strategy against this disease through the restoration of PI3K activity.

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<![CDATA[Vascular permeability in retinopathy is regulated by VEGFR2 Y949 signaling to VE-cadherin]]> https://www.researchpad.co/product?articleinfo=N4b1935b5-48a1-45aa-bb03-72c2da96edee

Edema stemming from leaky blood vessels is common in eye diseases such as age-related macular degeneration and diabetic retinopathy. Whereas therapies targeting vascular endothelial growth factor A (VEGFA) can suppress leakage, side-effects include vascular rarefaction and geographic atrophy. By challenging mouse models representing different steps in VEGFA/VEGF receptor 2 (VEGFR2)-induced vascular permeability, we show that targeting signaling downstream of VEGFR2 pY949 limits vascular permeability in retinopathy induced by high oxygen or by laser-wounding. Although suppressed permeability is accompanied by reduced pathological neoangiogenesis in oxygen-induced retinopathy, similarly sized lesions leak less in mutant mice, separating regulation of permeability from angiogenesis. Strikingly, vascular endothelial (VE)-cadherin phosphorylation at the Y685, but not Y658, residue is reduced when VEGFR2 pY949 signaling is impaired. These findings support a mechanism whereby VE-cadherin Y685 phosphorylation is selectively associated with excessive vascular leakage. Therapeutically, targeting VEGFR2-regulated VE-cadherin phosphorylation could suppress edema while leaving other VEGFR2-dependent functions intact.

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<![CDATA[Primary cilia control glucose homeostasis via islet paracrine interactions]]> https://www.researchpad.co/product?articleinfo=N6f79b41c-e106-4677-ad62-8dad158a9123

Significance

The primary cilium is a small subcompartment of the cell but has powerful influence on pancreatic islet function. In this study, we find a critical role for cilia in regulating β-cell function and energy metabolism. Importantly, the deletion of β-cell cilia disrupts intercellular communication and leads to islet dysfunction and diabetes, as seen in a number of human ciliopathy syndromes. These results should help elucidate pathophysiology of human ciliopathy and aid the development of pharmacologic agents targeting primary cilia that may lead to a more effective treatment for human diabetes.

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<![CDATA[Comparative proteogenomics profiling of non-small and small lung carcinoma cell lines using mass spectrometry]]> https://www.researchpad.co/product?articleinfo=N5fa2f86e-7b50-4064-be9f-8013db4361b6

Background

Evidences indicated that non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) might originate from the same cell type, which however ended up to be two different subtypes of lung carcinoma, requiring different therapeutic regimens. We aimed to identify the differences between these two subtypes of lung cancer by using integrated proteome and genome approaches.

Methods and Materials

Two representative cell lines for each lung cancer subtype were comparatively analysed by quantitative proteomics, and their corresponding transcriptomics data were obtained from the Gene Expression Omnibus database. The integrated analyses of proteogenomic data were performed to determine key differentially expressed proteins that were positively correlated between proteomic and transcriptomic data.

Result

The proteomics analysis revealed 147 differentially expressed proteins between SCLC and NSCLC from a total of 3,970 identified proteins. Combined with available transcriptomics data, we further confirmed 14 differentially expressed proteins including six known and eight new lung cancer related proteins that were positively correlated with their transcriptomics data. These proteins are mainly involved in cell migration, proliferation, and invasion.

Conclusion

The proteogenomic data on both NSCLC and SCLC cell lines presented in this manuscript is complementary to existing genomic and proteomic data related to lung cancers and will be crucial for a systems biology-level understanding of the molecular mechanism of lung cancers. The raw mass spectrometry data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD015270.

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<![CDATA[Endogenous itaconate is not required for particulate matter-induced NRF2 expression or inflammatory response]]> https://www.researchpad.co/product?articleinfo=N2f0ba49a-4b07-4979-ba16-4e28662922d5

Particulate matter (PM) air pollution causes cardiopulmonary mortality via macrophage-driven lung inflammation; however, the mechanisms are incompletely understood. RNA-sequencing demonstrated Acod1 (Aconitate decarboxylase 1) as one of the top genes induced by PM in macrophages. Acod1 encodes a mitochondrial enzyme that produces itaconate, which has been shown to exert anti-inflammatory effects via NRF2 after LPS. Here, we demonstrate that PM induces Acod1 and itaconate, which reduced mitochondrial respiration via complex II inhibition. Using Acod1-/- mice, we found that Acod1/endogenous itaconate does not affect PM-induced inflammation or NRF2 activation in macrophages in vitro or in vivo. In contrast, exogenous cell permeable itaconate, 4-octyl itaconate (OI) attenuated PM-induced inflammation in macrophages. OI was sufficient to activate NRF2 in macrophages; however, NRF2 was not required for the anti-inflammatory effects of OI. We conclude that the effects of itaconate production on inflammation are stimulus-dependent, and that there are important differences between endogenous and exogenously-applied itaconate.

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<![CDATA[Correction: Endothelial PKA activity regulates angiogenesis by limiting autophagy through phosphorylation of ATG16L1]]> https://www.researchpad.co/product?articleinfo=N63d19ade-13da-4b37-a1de-55afc96d0697 ]]> <![CDATA[Hog1 activation delays mitotic exit via phosphorylation of Net1]]> https://www.researchpad.co/product?articleinfo=Nf904df69-b51d-4397-ad24-641ac20c8708

Significance

Proper chromosome segregation is critical for the maintenance of genomic information in every cell division, which is required for cell survival. Cells have orchestrated a myriad of control mechanisms to guarantee proper chromosome segregation. Upon stress, cells induce a number of adaptive responses to maximize survival that range from regulation of gene expression to control of cell-cycle progression. We have found here that in response to osmostress, cells also regulate mitosis to ensure proper telomeric and rDNA segregation during adaptation. Osmostress induces a Hog1-dependent delay of cell-cycle progression in early mitosis by phosphorylating Net1, thereby impairing timely nucleolar release and activation of Cdc14, core elements of mitosis regulation. Thus, Hog1 activation prevents segregation defects to maximize survival.

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<![CDATA[Incomplete immune reconstitution in HIV/AIDS patients on antiretroviral therapy: Challenges of immunological non‐responders]]> https://www.researchpad.co/product?articleinfo=N484aeac8-0ce1-4cf2-9d01-c941b735b83f

Abstract

The morbidity and mortality of HIV type‐1 (HIV‐1)‐related diseases were dramatically diminished by the grounds of the introduction of potent antiretroviral therapy, which induces persistent suppression of HIV‐1 replication and gradual recovery of CD4+ T‐cell counts. However, ∼10–40% of HIV‐1‐infected individuals fail to achieve normalization of CD4+ T‐cell counts despite persistent virological suppression. These patients are referred to as “inadequate immunological responders,” “immunodiscordant responders,” or “immunological non‐responders (INRs)” who show severe immunological dysfunction. Indeed, INRs are at an increased risk of clinical progression to AIDS and non‐AIDS events and present higher rates of mortality than HIV‐1‐infected individuals with adequate immune reconstitution. To date, the underlying mechanism of incomplete immune reconstitution in HIV‐1‐infected patients has not been fully elucidated. In light of this limitation, it is of substantial practical significance to deeply understand the mechanism of immune reconstitution and design effective individualized treatment strategies. Therefore, in this review, we aim to highlight the mechanism and risk factors of incomplete immune reconstitution and strategies to intervene.

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<![CDATA[Retromer subunit, VPS29, regulates synaptic transmission and is required for endolysosomal function in the aging brain]]> https://www.researchpad.co/product?articleinfo=N5248f9c2-e521-4c91-8b44-9718377bb06d

Retromer, including Vps35, Vps26, and Vps29, is a protein complex responsible for recycling proteins within the endolysosomal pathway. Although implicated in both Parkinson’s and Alzheimer’s disease, our understanding of retromer function in the adult brain remains limited, in part because Vps35 and Vps26 are essential for development. In Drosophila, we find that Vps29 is dispensable for embryogenesis but required for retromer function in aging adults, including for synaptic transmission, survival, and locomotion. Unexpectedly, in Vps29 mutants, Vps35 and Vps26 proteins are normally expressed and associated, but retromer is mislocalized from neuropil to soma with the Rab7 GTPase. Further, Vps29 phenotypes are suppressed by reducing Rab7 or overexpressing the GTPase activating protein, TBC1D5. With aging, retromer insufficiency triggers progressive endolysosomal dysfunction, with ultrastructural evidence of impaired substrate clearance and lysosomal stress. Our results reveal the role of Vps29 in retromer localization and function, highlighting requirements for brain homeostasis in aging.

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