Cell Types Research Articles

Causal relationship between immune cells and acute myeloid leukemia: a two-sample Mendelian randomization study.

Immune cells are crucial in the etiology of acute myeloid leukemia (AML). Given the genetic, epigenetic, and clonal complexities of AML, pinpointing factors linked to immunotherapy presents a formidable challenge. Moreover, investigations into the connection between immune cells and AML are still in their infancy, necessitating further studies to decode the intricate connections involved. Based on Mendelian independent distribution law, Mendelian randomisation (MR) is an analytical method mainly used in epidemiological aetiology inference. This bidirectional two-sample MR study aims to investigate the causal link between immune cell phenotypes and AML. Pooled phenotypic data from 3,757 individuals in a Sardinian cohort, encompassing 731 immune cell phenotypes, were utilized. Aggregate data on AML were sourced from the FinnGen project of the Finnish Biobank. We analyzed the sensitivity of the results and evaluated heterogeneity, employing Cochran's Q test in conjunction with MR-Egger and MR-Presso to assess pleiotropy levels. 26 distinct immune cell types were identified that potentially linked causally with AML. Furthermore, our analysis indicated a bidirectional causal link between Resting Treg % CD4 Treg, BAFF-R on memory B cells and AML. This investigation delineates the causal link between immune cell phenotypes and the pathogenesis of AML, thereby unveiling potential therapeutic avenues to modulate immune cell functions in AML patients. It aims to discover innovative therapeutic strategies that target immune evasion tactics to reinstate immune responses against leukemia.

Preservation of Murine Whole Eyes With Supplemented UW Cold Storage Solution: Anatomical Considerations.

Retinal ganglion cell (RGC) apoptosis and axon regeneration are the principal obstacles challenging the development of successful whole eye transplantation (WET). The purpose of this study was to create a neuroprotective cocktail that targets early events in the RGC intrinsic apoptotic program to stabilize RGCs in a potential donor eye. University of Wisconsin (UW) solution was augmented with supplements known to protect RGCs. Supplements targeted tyrosine kinase signaling, histone deacetylase activity, K+ ion efflux, macroglial stasis, and provided energy support. Modified UW (mUW) solutions with individual supplements were injected into the vitreous of enucleated mouse eyes, which were then stored in cold UW solution for 24 hours. Histopathology, immunostaining of individual retinal cell types, and analysis of cell-specific messenger RNAs (mRNAs) were used to identify supplements that were combined to create optimal mUW solution. UW and mUW solutions reduced ocular edema and focal ischemia in globes stored in cold storage. Two major issues were noted after cold storage, including retinal detachment and reduction in glial fibrillary acidic protein staining in astrocytes. A combination of supplements resolved both these issues and performed better than the individual supplements alone. Cold storage resulted in a reduction in cell-specific mRNAs, even though it preserved the corresponding protein products. Eyes treated with optimal mUW solution exhibited preservation of retinal and cellular architecture, but did display a decrease in mRNA levels, suggesting that cold storage induced cellular stasis. Application of optimal mUW solution lowers an important barrier to the development of a successful whole eye transplantation procedure.

Role of Balanced Involvement of the ICOS/ICOSL/Osteopontin Network in Cutaneous Wound Healing.

Inducible T-cell costimulator (ICOS, CD278) is a costimulatory receptor primarily expressed by activated T cells. It binds to ICOS ligand (ICOSL, CD275), which is expressed by various immune and non-immune cell types, particularly in inflamed tissues. ICOSL can also bind to osteopontin (OPN), a protein that functions both as a component of the extracellular matrix and as a soluble pro-inflammatory cytokine. Previous studies, including ours, have shown that ICOS and ICOSL play a role in skin wound healing, as mice deficient in either ICOS or ICOSL exhibit delayed healing. The aim of this study was to investigate the involvement of the ICOS/ICOSL/OPN network in skin wound healing by analyzing mice that are single knockouts for ICOS, ICOSL, or OPN, or double knockouts for ICOS/OPN or ICOSL/OPN. Our results showed that wound healing is impaired in all single knockout strains, but not in the two double knockout strains. Cellular and molecular analyses of the wound healing sites revealed that the healing defect in the single knockout strains is associated with reduced neutrophil infiltration and decreased expression of α-SMA (a marker of myofibroblasts), IL-6, TNFα, and VEGF. In contrast, the normalization of wound closure observed in the double knockout strains was primarily linked to increased vessel formation. A local treatment with recombinant ICOS-Fc improved healing in all mouse strains expressing ICOSL, but not in those lacking ICOSL, and led to a local increase in vessel formation and macrophage recruitment, predominantly of the M2 type.

POU3F4 up-regulates Gli1 expression and promotes neuronal differentiation and synaptic development of hippocampal neural stem cells

BackgroundNeural stem cells (NSCs) are considered to be the most promising cell type for cell replacement therapy in neurodegenerative diseases. However, their low neuronal differentiation ratio impedes their application in such conditions. Elucidating the molecular mechanism of NSC differentiation may provide the necessary experimental basis for expanding their application. Previous studies have indicated that POU3F4 can induce neuronal differentiation of NSCs, this study aims to underly the possible exact mechanism of POU3F4 on the NSC differentiation and development.MethodsNSCs were isolated and cultured from the hippocampus of neonatal mice. The frozen hippocampal sections were prepared for immunohistochemical staining. Synaptic development was assessed using electron microscopy. High-throughput sequencing was employed to analyze the gene expression profile following the overexpression of Brn4. Gene expression levels were determined through Western blotting and qRT-PCR. Cell cycle and differentiation were evaluated using flow cytometry and immunofluorescent staining.ResultsIt was found that POU3F4 promoted the neuronal differentiation of hippocampal NSCs and synapse development, and inhibited NSC proliferation. POU3F4-deficient mice exhibited impairments in learning and memory. RNA sequencing and ChIP assays confirmed that Gli1 was downstream of POU3F4. Loss and gain function experiments indicated that Gli1 mediated POU3F4 promoting neuronal differentiation and synapse development. Forced expression of Gli1 in hippocampus improved learning and memory function of animal models.ConclusionsThe results suggest that POU3F4 and Gli1 promote neuronal differentiation and synaptic development of NSCs, and that Gli1 partially mediates the effects of POU3F4.Graphical abstract

Exploring the genetic associations and causal relationships between antibody responses, immune cells, and various types of breast cancer.

There may be potential associations between various pathogens, antibody immune responses, and breast cancer (BC), but the specific mechanisms and causal relationships remain unclear. First, multiple Mendelian randomization (MR) methods were used for univariable MR analysis to explore potential causal relationships between 34 antibody immune responses (related to 12 pathogens), 46 antibody immune responses (related to 13 pathogens), antibody responses post-COVID-19 vaccination, 731 immune cell types, and various BC subtypes (including overall BC, ER-positive, ER-negative, Luminal A, Luminal B, Luminal B HER2-negative, HER2-positive, and triple-negative BC). The primary results were then subjected to reverse MR analysis, heterogeneity testing using Cochran's Q, and horizontal pleiotropy testing. Robust findings were further used to design mediation pathways involving antibody immune responses, immune cells, and BC. After adjusting the effect estimates using multivariable MR (MVMR), a two-step mediation analysis was conducted to explore mediation pathways and mediation proportions. Finally, linkage disequilibrium score regression (LDSC) was applied to analyze the genetic correlation between phenotypes along mediation pathways, and cross-phenotype association analysis (CPASSOC) was performed to identify pleiotropic SNPs among three phenotypes along these pathways. Bayesian colocalization tests were conducted on pleiotropic SNPs using the multiple-trait-coloc (moloc). We identified potential causal relationships between 15 antibody immune responses to 8 pathogens (Hepatitis B virus, Herpes Simplex Virus 2, Human Herpesvirus 6, Polyomavirus 2, BK polyomavirus, Cytomegalovirus, Helicobacter pylori, Chlamydia trachomatis), 250 immune cell phenotypes, and various BC subtypes. MVMR-adjusted mediation analysis revealed four potential mediation pathways. LDSC results showed no significant genetic correlation between phenotypes pairwise. CPASSOC analysis identified two potential mediation pathways with common pleiotropic SNPs (rs12121677, rs281378, rs2894250). However, none of these SNPs passed the Bayesian colocalization test by moloc. These results excluded horizontal pleiotropy, stabilizing MR analysis results. This study utilized MR methods to analyze potential causal relationships between various antibody immune responses, immune cell types, and BC subtypes, identifying four potential regulatory mediation pathways. The findings of this study offer potential targets and research directions for virus-related and immunotherapy-related studies, providing a certain level of theoretical support. However, limitations such as GWAS sample size constraints and unclear specific pathophysiological mechanisms need further improvement and validation in future studies.

Spatiotemporal distribution of neural crest cells in the common wall lizard Podarcis muralis.

Neural crest cells (NCCs) are migratory embryonic stem cells that give rise to a diverse set of cell types. Here we describe the dynamic distribution of NCCs in developing embryos of the common wall lizard Podarcis muralis inferred from 10 markers. Our aim is to provide insights into the NCC development of lacertid lizards and to infer evolutionary modifications by comparisons to other tetrapods. NCC migration is ongoing at oviposition, following three streams in the head and multiple in the trunk. From 21ss, we observe expression patterns indicating the beginning of differentiation toward mesenchymal and neuronal fates. By 35ss, migration is restricted to caudal levels, and fully differentiated chromaffin cells are observed. We find that some markers show patterns that differ from other tetrapods. For example, the antibody HNK-1 labels three NCC streams from the hindbrain while some comparable reptile studies describe four. However, the information emerging from all markers combined shows that the overall spatiotemporal distribution of NCCs in the common wall lizard is largely conserved with that of other tetrapods. Our study highlights the dynamic nature of seemingly canonical marker genes and provides the first description of spatiotemporal NCC dynamics in a lacertid lizard.

Wildfire-relevant woodsmoke and extracellular vesicles (EVs): Alterations in EV proteomic signatures involved in extracellular matrix degradation and tissue injury in airway organotypic models

Wildfires adversely impact air quality and public health worldwide. Exposures to wildfire smoke are linked to adverse health outcomes, including cardiopulmonary diseases. Critical research gaps remain surrounding the underlying biological pathways leading to wildfire-induced health effects. The regulation of intercellular communication and downstream toxicity driven by extracellular vesicles (EVs) is an important, understudied biological mechanism. This study investigated EVs following a wildfire smoke-relevant in vitro exposure. We hypothesized that woodsmoke (WS) would alter the proteomic content of EVs secreted in organotypic in vitro airway models. Exposures were carried out using a tri-culture model of alveolar epithelial cells, fibroblasts, and endothelial cells and a simplified co-culture model of alveolar epithelial cells and fibroblasts to inform responses across different cell populations. Epithelial cells were exposed to WS condensate and EVs were isolated from basolateral conditioned medium following 24 h exposure. WS exposure did not influence EV particle characteristics, and it moderately increased EV count. Exposure caused the differential loading of 25 and 35 proteins within EVs collected from the tri- and co-culture model, respectively. EV proteins involved in extracellular matrix degradation and wound healing were consistently modulated across both models. However, distinct proteins involved in the wound healing pathway were altered between models, suggesting unique but concerted efforts across cell types to communicate in response to injury. These findings demonstrate that a wildfire-relevant exposure alters the EV proteome and suggest an impact on EV-mediated intercellular communication. Overall, results demonstrate the viability of organotypic approaches in evaluating EVs to investigate exposure-induced biomarkers and underlying mechanisms. Findings also highlight the impact of differences in the biological complexity of in vitro models used to evaluate the effects of inhaled toxicants.

Stem Cell Patentability: Legal Challenges

Stem cells are versatile cells capable of self-renewal and differentiation into different specialized cell types. Their immense potential has led to a surge in research and practical applications medicine. Patentability of the stem cells has been a subject of controversy, with concerns that restrictions on access to crucial technologies could hinder the translation of research into practical medical applications. It is a promising field that's rapidly advancing and has the potential to revolutionize modern medicine. The patentability of stem cells faces several legal challenges, including ethical, moral, and religious concerns, as well as difficulties in obtaining a patent license. Patent protection is crucial for driving innovation and commercial success in regenerative medicine and life sciences. This article examines the patentability restrictions and specific challenges associated with human stem cell patents in Europe and the United States.

Plasma-derived exosomes of Edwardsiella piscicida challenged olive flounder (Paralichthys olivaceus): Characterization and miRNA profiling for potential biomarkers screening

Exosomes are released from multiple cell types as part of their normal physiology as well as during acquired abnormalities. In this study, we investigated the effect of pathogenic Edwardsiella piscicida infection on olive flounder (Paralichthys olivaceus) exosomes at morphometric, physicochemical, and molecular levels. Unique cup-shaped exosomes were isolated from the plasma of non-infected (PBS-Exo) and E. piscicida experimentally challenged (Ep-Exo) olive flounder using ultracentrifugation. The average particle size, concentration, and zeta potential were 150.9 ± 6.9 nm, 5.67 × 1010 particles/mL, and −25.6 ± 1.36 mV for PBS-Exo while 138.7 ± 1.9 nm, 1.22 × 1011 particles/mL, and −35 ± 1.82 mV for Ep-Exo, respectively. Expression of tetraspanin markers (CD81, CD9, and CD63) confirmed the presence of olive flounder exosomes. Differentially expressed (DE) known (9) and novel (29) miRNAs (log2 fold change ≥1; p < 0.05) were identified in the Ep-Exo that could be potential as diagnostic biomarkers for the infection. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that the predicted target genes of the DE miRNAs were highly enriched in metabolic and immune roles. Both PBS-Exo and Ep-Exo were non-toxic in vitro (up to 100 μg/mL) and in vivo (up to 400 μg/mL). Compared to the vehicle, PBS-Exo at 50 μg/mL induced Nf-kB (>1.50-fold) while at 100 μg/mL, Il8, Il10, Nf-kB, P53, and Inf were induced (>1.50-fold) in fathead minnow cells (FHMs). This suggests that the PBS-Exo contains molecules that moderately stimulate gene expression. In the future, validating the exact olive flounder immune response target genes that interact with DE miRNAs in Ep-Exo will be crucial for investigating the host-pathogen interactions, immune defense mechanisms, and therapeutic targets for olive flounder against E. piscicida infection.

Profiling of insulin-resistant kidney models and human biopsies reveals common and cell-type-specific mechanisms underpinning Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end stage kidney failure worldwide, of which cellular insulin resistance is a major driver. Here, we study key human kidney cell types implicated in DKD (podocytes, glomerular endothelial, mesangial and proximal tubular cells) in insulin sensitive and resistant conditions, and perform simultaneous transcriptomics and proteomics for integrated analysis. Our data is further compared with bulk- and single-cell transcriptomic kidney biopsy data from early- and advanced-stage DKD patient cohorts. We identify several consistent changes (individual genes, proteins, and molecular pathways) occurring across all insulin-resistant kidney cell types, together with cell-line-specific changes occurring in response to insulin resistance, which are replicated in DKD biopsies. This study provides a rich data resource to direct future studies in elucidating underlying kidney signalling pathways and potential therapeutic targets in DKD.

Optogenetic control of dopamine receptor 2 reveals a novel aspect of dopaminergic neurotransmission in motor function.

Dopaminergic neurotransmission plays a crucial role in motor function through the coordination of dopamine receptor (DRD) subtypes, such as DRD1 and DRD2, thus the functional imbalance of these receptors can lead to Parkinson's disease. However, due to the complexity of dopaminergic circuits in the brain, it is limited to investigating the individual functions of each DRD subtype in specific brain regions. Here, we developed a light-responsive chimeric DRD2, OptoDRD2, which can selectively activate DRD2-like signaling pathways with spatiotemporal resolution. OptoDRD2 was designed to include the light-sensitive component of rhodopsin and the intracellular signaling domain of DRD2. Upon illumination with blue light, OptoDRD2 triggered DRD2-like signaling pathways, such as Gαi/o subtype recruitment, a decrease in cAMP levels, and ERK phosphorylation. To explore unknown roles of DRD2 in glutamatergic cell populations of basal ganglia circuitry, OptoDRD2 was genetically expressed in excitatory neurons in lateral globus pallidus (LGP) of the male mouse brain. The optogenetic stimulation of OptoDRD2 in the LGP region affected a wide range of locomotion-related parameters, such as increased frequency of movement and decreased immobility time, resulting in the facilitation of motor function of living male mice. Therefore, our findings indicate a potential novel role for DRD2 in the excitatory neurons of the LGP region, suggesting that OptoDRD2 can be a valuable tool enabling the investigation of unknown roles of DRD2 at specific cell types or brain regions.Significance Statement We developed a light-responsive chimeric dopamine receptor type 2, OptoDRD2, by combining the blue-light sensing part of rhodopsin and intracellular functional regions of DRD2. OptoDRD2 can selectively trigger DRD2-like downstream signaling pathways upon illumination of blue light. To explore unknown roles of DRD2 in glutamatergic cell populations of basal ganglia circuitry, OptoDRD2 was genetically expressed in excitatory neurons at lateral globus pallidus (LGP) in the mouse brain. Optogenetic stimulation of OptoDRD2 in living mice suggested a potential novel function of DRD2 in the LGP that enhances motor outputs. Therefore, OptoDRD2 enabled the precise control of DRD2-like signaling in specific cell types and brain regions, allowing the exploration of potential novel DRD2 functions in living mice.

Disruption of the C5a/C5aR1 axis confers protection against hookworm infection in lung.

Hookworms are soil-transmitted parasitic nematodes that penetrate the host skin before migrating to the lungs. With an estimated 500-700 million people infected worldwide, hookworm infections are a neglected tropical disease and a significant cause of morbidity, particularly in children, pregnant women, and immunocompromised individuals. Although there is ample evidence that complement activation is pivotal to elicit a protective host immune response against invasive pathogens, its role in hookworm infection remains insufficiently explored. Here, we investigated the complement anaphylatoxin, C5a, during the early lung stage of infection with Nippostrongylus brasiliensis in C57BL/6J wild type and C5aR1-/- mice. Despite the previously reported ability of lung larvae to evade complement activation, C5a was detectable locally in lung tissue and bronchoalveolar lavages. Surprisingly, C5aR1 presence directly contributed to the pathogenicity of hookworm infection. The burden of viable parasites in the lungs was mitigated in C5aR1-/- mice, compared to C57BL/6J mice 48 hours post-infection. Additionally, C5aR1-/- mice showed significantly reduced lung injury, lower cytokine release, attenuated alveolar hemorrhage, and limited alveolar-capillary barrier disruption. Neutrophils were the most abundant and highest C5aR1-expressing cell type in the alveolar space after infection. Deficiency of C5aR1 reduced the influx of neutrophils, monocytes, and eosinophils to the pulmonary airways. RNA sequencing of alveolar neutrophils revealed C5aR1-dependent regulation of the novel nuclear protein, DEDD2. In conclusion, our findings highlight the impact of C5aR1 signaling in neutrophils during hookworm infection uncovering an unexpected downside of complement activation in parasitic infection.

Tailoring cell therapies for diabetic metabolic phenotypes: a comparative study on the efficacy of various umbilical cord-derived cell regimens.

Given the high heterogeneity of type 2 diabetes mellitus (T2DM), it is imperative to develop personalized stem cell infusion regimen for targeted metabolic phenotype in order to ensure optimal therapeutic efficacy. In this study, we conducted a comparative analysis of 4 infusion regimens involving single and repeated infusions of human umbilical cord Wharton's jelly-derived MSCs (hucMSCs), single infusions of umbilical cord blood mononuclear cells (UCB), and sequential infusions of hucMSCs and UCB in T2DM rats. Results showed all 4 infusion regimens exhibited comparable efficacy in lowering fasting blood glucose levels and suppressing glucagon secretion. Single and double infusions of hucMSCs exhibited a tendency to migrate to the liver, thereby better at ameliorating hepatic glucose metabolism by enhancing glycogen synthesis and storage, promoting glycolysis, inhibiting gluconeogenesis, and improving insulin signal transduction. The sequential infusion of hucMSCs and UCB demonstrated specific cell tropism toward the pancreas, leading to prolonged glucose-lowering effects following a glucose tolerance test, restoration of early-phase insulin secretion, stimulation of islet beta cell proliferation and improvement in the beta/alpha ratio. Multiple injections, regardless of cell type, reduced the expression of systemic chronic inflammatory markers such as IL-1β, IL-6, IL-17, IL-22, and IFN-γ. Finally, a single dose of UCB exhibited a greater tendency to target visceral fat and enhanced effectiveness in regulating levels of total cholesterol and triglycerides. In conclusion, our study provided personalized stem cell regimens for diverse T2DM metabolic phenotypes, thereby offering improved treatment alternatives for future clinical trials and applications.

NAD + activates renal metabolism and protects from chronic kidney disease in a model of Alport syndrome.

Chronic kidney disease (CKD) is associated with renal metabolic disturbances, including impaired fatty acid oxidation (FAO). Nicotinamide adenine dinucleotide (NAD + ) is a small molecule that participates in hundreds of metabolism-related reactions. NAD + levels are decreased in CKD, and NAD + supplementation is protective. However, both the mechanism of how NAD + supplementation protects from CKD, as well as the cell types involved, are poorly understood. Using a mouse model of Alport syndrome, we show that nicotinamide riboside (NR), an NAD + precursor, stimulates renal peroxisome proliferator-activated receptor alpha signaling and restores FAO in the proximal tubules, thereby protecting from CKD in both sexes. Bulk RNA-sequencing shows that renal metabolic pathways are impaired in Alport mice and activated by NR in both sexes. These transcriptional changes are confirmed by orthogonal imaging techniques and biochemical assays. Single nuclei RNA-sequencing and spatial transcriptomics, both the first of their kind from Alport mice, show that NAD + supplementation restores FAO in proximal tubule cells. Finally, we also report, for the first time, sex differences at the transcriptional level in this Alport model. In summary, we identify a nephroprotective mechanism of NAD + supplementation in CKD, and we demonstrate that the proximal tubule cells substantially contribute to this benefit.

Airway ciliary microenvironment responses in mice with primary ciliary dyskinesia and central pair apparatus defects

Dysfunction of motile cilia can impair mucociliary clearance in the airway and result in primary ciliary dyskinesia (PCD). We previously showed that mutations in central pair apparatus (CPA) genes perturb ciliary motility and result in PCD in mouse models. However, little is known about how epithelial cell types in the ciliary microenvironment of the upper airway respond to defects in ciliary motility and mucociliary clearance. Here, we have used single-cell RNA sequencing to investigate responses in tracheal epithelial cells from mice with mutations in CPA genes Cfap221/ Pcdp1, Cfap54, and Spef2. Expected cell types were identified, along with an unidentified cell type not expressing markers of typical airway cells. Deuterosomal cells were found to exist in two states that differ largely in expression of genes involved in differentiation into ciliated cells. Functional enrichment analysis of differentially expressed genes (DEGs) revealed important cellular functions and molecular pathways for each cell type that are altered in mutant mice. Overlapping DEGs shed light on general responses to cilia dysfunction, while unique DEGs indicate that some responses may be specific to the individual mutation and ciliary defect.

Diagnosis and typing of leukemia using a single peripheral blood cell through deep learning

AbstractLeukemia is highly heterogeneous, meaning that different types of leukemia require different treatments and have different prognoses. Current clinical diagnostic and typing tests are complex and time‐consuming. In particular, all of these tests rely on bone marrow aspiration, which is invasive and leads to poor patient compliance, exacerbating treatment delays. Morphological analysis of peripheral blood cells (PBC) is still primarily used to distinguish between benign and malignant hematologic disorders, but it remains a challenge to diagnose and type these diseases solely by direct observation of peripheral blood(PB) smears by human experts. In this study, we apply a segmentation‐based enhanced residual network that uses progressive multigranularity training with jigsaw patches. It is trained on a self‐built annotated dataset of 21,208 images from 237 patients, including five types of benign white blood cells(WBCs) and eight types of leukemic cells. The network is not only able to discriminate between benign and malignant cells, but also to typify leukemia using a single peripheral blood cell. The network effectively differentiated acute promyelocytic leukemia (APL) from other types of acute myeloid leukemia (non‐APL), achieving a precision rate of 89.34%, a recall rate of 97.37%, and an F1 score of 93.18% for APL. In contrast, for non‐APL cases, the model achieved a precision rate of 92.86%, but a recall rate of 74.63% and an F1 score of 82.75%. In addition, the model discriminates acute lymphoblastic leukemia(ALL) with the Ph chromosome from those without. This approach could improve patient compliance and enable faster and more accurate typing of leukemias for early diagnosis and treatment to improve survival.

Cholesterol crystals in the pathogenesis of atherosclerosis.

The presence of cholesterol crystals (CCs) in tissues was first described more than 100 years ago. CCs have a pathogenic role in various cardiovascular diseases, including myocardial infarction, aortic aneurysm and, most prominently, atherosclerosis. Although the underlying mechanisms and signalling pathways involved in CC formation are incompletely understood, numerous studies have highlighted the existence of CCs at various stages of atheroma progression. In this Review, we summarize the mechanisms underlying CC formation and the role of CCs in cardiovascular disease. In particular, we explore the established links between lipid metabolism across various cell types and the formation of CCs, with a focus on CC occurrence in the vasculature. We also discuss CC-induced inflammation as one of the pathogenic features of CCs in the atheroma. Finally, we summarize the therapeutic strategies aimed at reducing CC-mediated atherosclerotic burden, including approaches to inhibit CC formation in the vasculature or to mitigate the inflammatory response triggered by CCs. Addressing CC formation might emerge as a crucial component in our broader efforts to combat cardiovascular disease.

Microglia States are Susceptible to Senescence and Cholesterol Dysregulation in Alzheimer's Disease.

Cellular senescence is a major contributor to aging-related degenerative diseases, including Alzheimer's disease (AD) but much less is known on the key cell types and pathways driving mechanisms of senescence in the brain. We hypothesized that dysregulated cholesterol metabolism is central to cellular senescence in AD. We analyzed whole transcriptomic data and utilized single-cell RNA seq integration techniques to unveil the convoluted cell-type-specific and sub-cell-type-state-specific senescence pathologies in AD using both ROSMAP and Sea-AD datasets. We identified that microglia are central components to AD associated senescence phenotypes in ROSMAP snRNA-seq data (982,384 nuclei from postmortem prefrontal cortex of 239 AD and 188 non-AD) among non-neuron cell types. We identified that homeostatic, inflammatory, phagocytic, lipid processing and neuronal surveillance microglia states were associated with AD associated senescence in ROSMAP (152,459 microglia nuclei from six regions of brain tissue of 138 early AD, 79 late AD and 226 control subject) and in Sea-AD (82,486 microglia nuclei of 42 dementia, 42 no dementia and 5 reference subjects) via integrative analysis, which preserves the meaningful biological information of microglia cell states across the datasets. We assessed top senescence associated bioprocesses including mitochondrial, apoptosis, oxidative stress, ER stress, endosomes, and lysosomes systems. Specifically, we found that senescent microglia have altered cholesterol related bioprocesses and dysregulated cholesterol. We discovered three gene co-expression modules, which represent the specific cholesterol related senescence transcriptomic signatures in postmortem brains. To validate these findings, the activation of specific cholesterol associated senescence transcriptomic signatures was assessed using integrative analysis of snRNA-seq data from iMGs (microglia induced from iPSCs) exposed to myelin, Abeta, and synaptosomes (56,454 microglia across two replicates of untreated and four treated groups). In vivo cholesterol associated senescence transcriptomic signatures were preserved and altered after treatment with AD pathological substrates in iMGs. This study provides the first evidence that dysregulation of cholesterol metabolism in microglia is a major driver of senescence pathologies in AD. Targeting cholesterol pathways in senescent microglia is an attractive strategy to slow down AD progression.

Leveraging Multi-omics to Disentangle the Complexity of Ovarian Cancer.

To better understand ovarian cancer lethality and treatment resistance, sophisticated computational approaches are required that address the complexity of the tumor microenvironment, genomic heterogeneity, and tumor evolution. The ovarian cancer tumor ecosystem consists of multiple tumors and cell types that support disease growth and progression. Over the last two decades, there has been a revolution in -omic methodologies to broadly define components and essential processes within the tumor microenvironment, including transcriptomics, metabolomics, proteomics, genome sequencing, and single-cell analyses. While most of these technologies comprehensively characterize a single biological process, there is a need to understand the biological and clinical impact of integrating multiple -omics platforms. Overall, multi-omics is an intriguing analytic framework that can better approximate biological complexity; however, data aggregation and integration pipelines are not yet sufficient to reliably glean insights that affect clinical outcomes.

MiR-23b-3p, miR-126-3p and GAS5 delivered by extracellular vesicles inhibit breast cancer xenografts in zebrafish

BackgroundExtracellular vesicles (EVs) are a group of nanoscale cell-derived membranous structures secreted by all cell types, containing molecular cargoes involved in intercellular communication. EVs can be used to mimic “nature’s delivery system” to transport nucleic acids, peptides, lipids, and metabolites to target recipient cells. EVs offer a range of advantages over traditional synthetic carriers, thus paving the way for innovative drug delivery approaches that can be used in different diseases, including cancer. Here, by using breast cancer (BC) cells treated with the multi-kinase inhibitor sorafenib, we generated EVs enriched in specific non-coding RNAs (miR-23b-3p, miR-126-3p, and the long ncRNA GAS5) and investigated their potential impact on the aggressive properties of the BC in vitro and in vivo using zebrafish.MethodsEVs were collected from 4 different BC cell lines (HCC1937, MDA-MB-231, MCF-7, and MDA-MB-453) and characterized by western blotting, transmission electron microscopy and nanoparticle tracking analysis. Levels of encapsulated miR-23b-3p, miR-126-3p, and GAS5 were quantified by ddPCR. The role of the EVs as carriers of ncRNAs in vivo was established by injecting MDA-MB-231 and MDA-MB-453 cells into zebrafish embryos followed by EV-based treatment of the xenografts with EVs rich in miR-23b-3p, miR-126-3p and GAS5.ResultsddPCR analysis revealed elevated levels of miR-23b-3p, miR-126-3p, and GAS5, encapsulated in the EVs released by the aforementioned cell lines, following sorafenib treatment. The use of EVs as carriers of these specific ncRNAs in the treatment of BC cells resulted in a significant increase in the expression levels of the three ncRNAs along with the inhibition of cellular proliferation in vitro. In vivo experiments demonstrated a remarkable reduction of xenograft tumor area, suppression of angiogenesis, and decreased number of micrometastasis in the tails after administration of EVs enriched with these ncRNAs.ConclusionsOur study demonstrated that sorafenib-induced EVs, enriched with specific tumor-suppressor ncRNAs, can effectively inhibit the aggressive BC characteristics in vitro and in vivo. Our findings indicate an alternative way to enrich EVs with specific tumor-suppressor ncRNAs by treating the cells with an anticancer drug and support the development of new potential experimental molecular approaches to target the aggressive properties of cancer cells.