Cell Phenotype Research Articles

Toward generalizable phenotype prediction from single-cell morphology representations

BackgroundFunctional cell processes (e.g., molecular signaling, response to stimuli, mitosis, etc.) impact cell phenotypes, which scientists can measure with cell morphology. However, linking these measurements with phenotypes remains challenging because it requires manually annotated labels. We propose that nuclear morphology can be a predictive marker for cell phenotypes that are generalizable across contexts.MethodsWe reanalyzed a pre-labeled, publicly-available nucleus microscopy dataset from the MitoCheck consortium. We extracted single-cell morphology features using CellProfiler and DeepProfiler, which provide robust processing pipelines. We trained multinomial, multi-class elastic-net logistic regression models to classify nuclei into one of 15 phenotypes such as ‘Anaphase,’ ‘Apoptosis’, and ‘Binuclear’. We rigorously assessed performance using F1 scores, precision-recall curves, and a leave-one-image-out (LOIO) cross-validation analysis. In LOIO, we retrained models using cells from every image except one and predicted phenotype in the held-out image, repeating this procedure for all images. We evaluated each morphology feature space, a concatenated feature space, and several feature space subsets (e.g., nuclei AreaShape features only). We applied models to the Joint Undertaking in Morphological Profiling (JUMP) data to assess performance using a different dataset.ResultsIn a held-out test set, we observed an overall F1 score of 0.84. Individual phenotype scores ranged from 0.64 (moderate performance) to 0.99 (high performance). Phenotypes such as ‘Elongated’, ‘Metaphase’, and ‘Apoptosis’ showed high performance. While CellProfiler and DeepProfiler features were generally equally effective, concatenation yielded the best results for 9/15 phenotypes. LOIO showed a performance decline, indicating our model could not reliably predict phenotypes in new images. Poor performance was unrelated to illumination correction or model selection. Applied to the JUMP data, models trained using nuclear AreaShape features only increased alignment with the annotated MitoCheck data (based on UMAP space). This approach implicated many chemical and genetic perturbations known to be associated with specific phenotypes.DiscussionPoor LOIO performance demonstrates challenges of single-cell phenotype prediction in new datasets. We propose several strategies that could pave the way for more generalizable methods in single-cell phenotype prediction, which is a step toward morphology representation ontologies that would aid in cross-dataset interpretability.

Chronic inflammation and vascular cell plasticity in atherosclerosis.

Vascular smooth muscle cells, endothelial cells and macrophages undergo phenotypic conversions throughout atherosclerosis progression, both as a consequence of chronic inflammation and as subsequent drivers of it. The inflammatory hypothesis of atherosclerosis has been catapulted to the forefront of cardiovascular research as clinical trials have shown that anti-inflammatory therapy reduces adverse cardiovascular events. However, no current therapies have been specifically designed to target the phenotype of plaque cells. Fate mapping has revealed that plaque cells convert to detrimental and beneficial cell phenotypes during atherosclerosis, with cumulative evidence highlighting that vascular cell plasticity is intimately linked with plaque inflammation, ultimately impacting lesion stability. Here we review vascular cell plasticity during atherosclerosis in the context of the chronic inflammatory plaque microenvironment. We highlight the need to better understand how plaque cells behave during therapeutic intervention. We then propose modulating plaque cell phenotype as an unexplored therapeutic paradigm in the clinical setting.

Plasma cell-free DNA chromatin immunoprecipitation profiling depicts phenotypic and clinical heterogeneity in advanced prostate cancer.

Cell phenotype underlies prostate cancer presentation and treatment resistance and can be regulated by epigenomic features. However, the osteotropic tendency of prostate cancer limits access to metastatic tissue, meaning most prior insights into prostate cancer chromatin biology are from preclinical models that do not fully represent disease complexity. Noninvasive chromatin immunoprecipitation of histones in plasma cell-free in humans may enable capture of disparate prostate cancer phenotypes. Here, we analyzed activating promoter- and enhancer-associated H3K4me2 from cfDNA in metastatic prostate cancer enriched for divergent patterns of metastasis and diverse clinical presentation. H3K4me2 density across prostate cancer genes, accessible chromatin, and lineage-defining transcription factor binding sites correlated strongly with circulating tumor DNA (ctDNA) fraction-demonstrating capture of prostate cancer-specific biology and informing the development of a statistical framework to adjust for ctDNA fraction. Chromatin hallmarks mirrored synchronously measured clinico-genomic features: bone versus liver-predominant disease, serum PSA, biopsy-confirmed histopathological subtype, and RB1 deletions convergently indicated phenotype segregation along an axis of differential androgen receptor activity and neuroendocrine identity. Detection of lineage switching after sequential progression on systemic therapy in select patients indicates potential utility for individualized resistance monitoring. Epigenomic footprints of metastasis-induced normal tissue destruction were evident in bulk cfDNA from two patients. Finally, a public epigenomic resource was generated using a distinct chromatin marker that has not been widely investigated in prostate cancer. These results provide insight into the adaptive molecular landscape of aggressive prostate cancer and endorse plasma cfDNA chromatin profiling as a biomarker source and biological discovery tool.

Exploring the Role of Fibroblasts in Promoting Neuroblastoma Cell Migration and Invasion

Neuroblastoma, the most common pediatric extracranial solid tumor, arises from the malignant transformation of neural crest progenitors in the peripheral nervous system. Its clinical and genetic heterogeneity poses significant challenges, especially in high-risk patients with metastatic disease. Two plastic neuroblastoma cell phenotypes, adrenergic (ADR) and mesenchymal (MES), have been identified. Notably, MES neuroblastoma cells exhibit increased migration and chemoresistance. Cancer-associated fibroblasts (CAFs) in the tumor microenvironment further promote tumor aggressiveness by enhancing cancer cell proliferation, extracellular matrix remodeling, angiogenesis and metastasis. This study explored the role of non-activated fibroblasts in ADR and MES neuroblastoma cell proliferation, migration and invasion in vitro and in vivo. Results showed that MES and ADR neuroblastoma cells influenced fibroblast activation into CAFs differently, with MES cells promoting a more invasive environment leading to tumor spread. These findings enhance our understanding of how ADR and MES phenotypes contribute to the formation of a pro-metastatic niche by activating fibroblasts in CAFs. This insight could inform new therapeutic strategies targeting the tumor microenvironment to prevent neuroblastoma metastasis.

Genetic Disruption of Blimp-1 Drastically Augments the Antitumor Efficacy of BCMA-Targeting CAR-T Cells.

Chimeric antigen receptor-T (CAR-T) cells directed against B-cell maturation antigen (BCMA) are an effective treatment for multiple myeloma (MM), but short persistence and frequent relapses are challenges for this immunotherapy. This lack of durability has been attributed to the premature terminal differentiation of CAR-T cells which prevents the formation of long-lived memory cells that maintain anti-tumour responses. To improve long-term efficacy, we used CRISPR/Cas9-mediated gene editing to ablate the expression of the transcription factor Blimp-1. Blimp-1 knockout (KO) CAR-T cells displayed a memory-like phenotype compared to control (Mock) CAR-T cells, but had reduced effector function, with a striking loss of granzyme B. However, in a murine model of advanced MM, Blimp-1 KO CAR-T cells effectively slowed or even prevented disease progression, significantly outperforming Mock CAR-T cells in improving survival (p=0.006). To understand this enhanced in vivo effectiveness, Blimp-1 KO CAR-T cells were characterised after being repeatedly challenged with tumour cells in vitro. In this setting, Blimp-1 KO CAR-T cells maintained a highly active state with high expression of memory markers, but crucially, demonstrated enhanced effector function and increased energetic capacity. RNA-sequencing analysis of tumour-exposed Blimp-1 KO CAR-T cells confirmed the presence of a memory-like transcriptomic signature and additionally, revealed enhanced ribosome biogenesis, and repressed CAR-T cell dysfunction as mechanisms that could be contributing to improved anti-tumour activity. Put together, our findings show that dampening Blimp-1 expression altered the phenotype and function of anti-BCMA CAR-T cells, leading to augmented therapeutic efficacy in MM.

Regulation of corneal epithelial differentiation: miR-141-3p promotes the arrest of cell proliferation and enhances the expression of terminal phenotype.

In recent years, different laboratories have provided evidence on the role of miRNAs in regulation of corneal epithelial metabolism, permeability and wound healing, as well as their alteration after surgery and in some ocular pathologies. We searched the available databases reporting miRNA expression in the human eye, looking for miRNAs highly expressed in central cornea, which could be crucial for maintenance of the epithelial phenotype. Using the rabbit RCE1(5T5) cell line as a model of corneal epithelial differentiation, we describe the participation of miR-141-3p as a possible negative regulator of the proliferative/migratory phenotype in corneal epithelial cells. The expression of miR-141-3p followed a time course similar to the differentiation-linked KRT3 cytokeratin, being delayed 24-48 hours relative to PAX6 expression; such result suggested that miR-141-3p only regulates the expression of terminal phenotype. Inhibition of miR-141-3p led to increased cell proliferation and motility, and induced the expression of molecular makers characteristic of an Epithelial Mesenchymal Transition (EMT). Comparison between the transcriptional profile of cells in which miR-141-3p was knocked down, and the transcriptomes from proliferative non-differentiated and differentiated stratified epithelia suggest that miR-141-3p is involved in the expression of terminal differentiation mediating the arrest of cell proliferation and inhibiting the EMT in highly motile early differentiating cells.

Fibro-adipogenic progenitor cells in skeletal muscle unloading: metabolic and functional impairments

BackgroundSkeletal muscle resident fibro-adipogenic progenitor cells (FAPs) control skeletal muscle regeneration providing a supportive role for muscle stem cells. Altered FAPs characteristics have been shown for a number of pathological conditions, but the influence of temporary functional unloading of healthy skeletal muscle on FAPs remains poorly studied. This work is aimed to investigate how skeletal muscle disuse affects the functionality and metabolism of FAPs.MethodsHindlimb suspension (HS) rat model employed to investigate muscle response to decreased usage. FAPs were purified from m. soleus functioning muscle (Contr) and after functional unloading for 7 and 14 days (HS7 and HS14). FAPs were expanded in vitro, and tested for: immunophenotype; in vitro expansion rate, and migration activity; ability to differentiate into adipocytes in vitro; metabolic changes. Crosstalk between FAPs and muscle stem cells was estimated by influence of medium conditioned by FAP’s on migration and myogenesis of C2C12 myoblasts. To reveal the molecular mechanisms behind unloading-induced alterations in FAP’s functionality transcriptome analysis was performed.ResultsFAPs isolated from Contr and HS muscles exhibited phenotype of MSC cells. FAPs in vitro expansion rate and migration were altered by functional unloading conditions. All samples of FAPs demonstrated the ability to adipogenic differentiation in vitro, however, HS FAPs formed fat droplets of smaller volume and transcriptome analysis showed fatty acids metabolism and PPAR signaling suppression. Skeletal muscle unloading resulted in metabolic reprogramming of FAPs: decreased spare respiratory capacity, decreased OCR/ECAR ratio detected in both HS7 and HS14 samples point to reduced oxygen consumption, decreased potential for substrate oxidation and a shift to glycolytic metabolism. Furthermore, C2C12 cultures treated with medium conditioned by FAPs showed diverse alterations: while the HS7 FAPs-derived paracrine factors supported the myoblasts fusion, the HS14-derived medium stimulated proliferation of C2C12 myoblasts; these observations were supported by increased expression of cytokines detected by transcriptome analysis.Conclusionthe results obtained in this work show that the skeletal muscle functional unloading affects properties of FAPs in time-dependent manner: in atrophying skeletal muscle FAPs act as the sensors for the regulatory signals that may stimulate the metabolic and transcriptional reprogramming to preserve FAPs properties associated with maintenance of skeletal muscle homeostasis during unloading and in course of rehabilitation.

A Safe and Convenient Method to Isolate Bone Marrow Mononuclear Cells in Clinical Practice.

Bone marrow mononuclear cells (BMMNCs) are becoming a promising cell therapy in regeneration medicine. BMMNCs are now obtained by density gradient centrifugation (DGC) in clinical practice, which is complicated and greatly influenced by human manipulation. Our objective is to develop a simple and safe method to isolate BMMNCs. Bone marrow was aspirated from nine minipigs. The optimal hypotonic sodium chloride (NaCl) concentration was first investigated based on the BMMNCs viability and lysis efficiency tests. Afterward, three different methods (ammonium chloride (NH4Cl) lysis, hypotonic NaCl lysis, and DGC) were used for BMMNCs isolation. Nucleated cell yield, residual red blood cells (RBCs) level, BMMNCs viability, apoptotic cell percentage, and colony-forming ability were measured in three groups. Cell morphology, cell phenotype, proliferative capacity, and osteogenic, adipogenic, and chondrogenic lineage differentiation potential of the bone marrow mesenchymal stem cells (BMSCs) were compared in three groups. 0.3% NaCl lysis group had optimal cell viability and lysis efficiency and the 0.3% NaCl lysis group had higher cell yield and lower RBCs remaining in BMMNCs compared to the DGC group. The BMSCs harvested from the NH4Cl lysis group had the worst proliferation ability. The NaCl lysis group was not inferior to the other two groups in terms of other biological characteristics of BMMNCs/BMSCs. The optimal concentration for hypotonic NaCl lysis to obtain BMMNCs is 0.3%. Compared with NH4Cl lysis and DGC, the 0.3% NaCl lysis may be a safe, appropriate, and low-cost method for BMMNCs isolation. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Extrajunctional CLDN10 cooperates with LAT1 and accelerates clear cell renal cell carcinoma progression

Background & aimsIn addition to their adhesive properties, cell adhesion molecules such as claudins (CLDNs) exhibit signaling ability to organize diverse cellular events. Although the CLDN-adhesion signaling stimulates or inhibits cancer progression, the underlying mechanism remains poorly established. Here, we verified whether and how CLDN10 promotes intracellular signals and malignant phenotypes in clear cell renal cell carcinoma (ccRCC).MethodsWe developed a novel monoclonal antibody that specifically recognizes CLDN10. By immunohistochemistry using this antibody, the clinicopathological significance of aberrant CLDN10 expression in 165 ccRCC patients was determined. We next generated the ccRCC cells (786-O, ACHN, and OS-RC-2) expressing CLDN10, and compared their phenotypes with those of control cells. Immunoprecipitation-mass spectrometry was used to identify a CLDN10-interacting protein, followed by evaluation of its association with CLDN10 and loss-of-functions in ccRCC cells.ResultsHigh CLDN10 expression predicted poor outcome in ccRCC patients and represented an independent prognostic marker for cancer-specific survival. Cell surface CLDN10 promoted cell viability, proliferation, and migration of ccRCC cells, as well as their tumor growth. CLDN10 also activated mTOR signaling and expression of downstream targets, including MYC target genes. Notably, we found that CLDN10 forms a complex with an amino acid transporter, LAT1, and that CLDN10–LAT1 signaling facilitates malignant phenotypes in ccRCC cells. Structural prediction and immunoprecipitation analysis results strongly suggest an interaction between CLDN10-TM1 (transmembrane domain 1) and LAT1-TM4.ConclusionsWe conclude that CLDN10–LAT1 signaling drives ccRCC progression. Taken together with our previous findings on CLDN–Src-family kinases signaling, CLDNs propagate distinct intracellular signals depending on their association with different binding partners.

Perianal Paget Disease With an Enteric Phenotype and Associated In-Situ/Dysplastic Glandular Component: Report of a Potentially Novel Entity and Review of the Literature.

Extramammary Paget disease is an uncommon cutaneous malignancy that primarily affects areas rich in apocrine glands. Here, we aim to present an 84-year-old woman with a distinctive perianal neoplastic process comprised of conventional Paget disease with an intertwined in-situ glandular component. Rare foci of glands embedded in pools of mucin were also identified in the most recent excision, consistent with mucinous adenocarcinoma. Immunohistochemical staining demonstrated an enteric phenotype of the tumor cells, with expression of keratin 20, caudal type homeobox transcription factor 2 (CDX2), and special AT-rich sequence binding protein 2 (SATB2) (patchy, weak); keratin 7 and BerEP4 staining were also noted. Molecular analysis via next generation sequencing revealed pathogenic variants in ERBB2, TP53, and SF3B1. Given the unique histomorphology and immunohistochemical staining pattern, suspicion for a colorectal primary tumor was high, however; extensive workup including imaging, testing for tumor markers, and colonoscopic evaluation has not identified any other lesion thus far. Multiple biopsies and excisions in the area demonstrated recurrent disease over a 4-year span; with no evidence of deep invasion or metastasis. This tumor appears to be exceptional among reports in the literature given its extensive in-situ glandular component; and we are not aware of any documented SF3B1 mutation to date. Disease recurrence in this patient highlights the need for clinical vigilance. Defining the molecular profile in these lesions can also be useful, particularly when assessing potential treatment options for advanced disease.

A 16-week progressive exercise training intervention in treatment-naïve chronic lymphocytic leukaemia: a randomised-controlled pilot study

BackgroundChronic lymphocytic leukaemia (CLL) typically presents with asymptomatic, early-stage disease that is monitored until disease progression (‘treatment-naïve’ CLL). The objective of this pilot study was to assess the feasibility and preliminary safety of an exercise program in treatment-naïve CLL. We also sought to preliminarily assess the impact of the exercise program on disease activity, as it has been proposed that exercise training may reduce disease outgrowth in treatment-naïve CLL.MethodsA total of 40 treatment-naïve CLL patients were recruited into this randomised-controlled pilot study, and after screening, n = 28 were randomised into a 16-week, home-based, partially supervised, personalised, progressive exercise intervention (n = 14: mean ± SD: age = 62 ± 12 years) or 16 weeks of usual care, control group (n = 14: mean ± SD: age = 61 ± 10 years). The primary outcome measures were safety (number and severity of adverse events) and feasibility (uptake, retention, and adherence to the trial). Disease activity (CD5+/CD19+ CLL cells clonally restricted to kappa or lambda) and other immune cell phenotypes, with a principal focus on T cells, were measured by flow cytometry. Other secondary outcomes included DEXA-derived body composition, cardiorespiratory and functional fitness, resting cardiovascular measures.ResultsTrial uptake was 40%, and the overall retention rate was 86%, with 79% of the exercise group and 93% of the control group completing the trial. Adherence to the exercise intervention was 92 ± 8%. One serious adverse event was reported unrelated to the trial, and one adverse event related to the trial was reported. The exercise intervention elicited a 2% increase in DEXA-derived lean mass in the exercise group compared with a 0.4% decrease in the control group (p = 0.01). No between-group differences were observed over time for whole-body mass, BMI, bone mineral density, body fat, blood pressure resting heart rate, or measures of cardiorespiratory or functional fitness (all p > 0.05). No between-group differences were observed over time for clonal CLL cells and CD4+ or CD8+ T-cell subsets (all p > 0.05).ConclusionThe exercise training program used in this study was feasible in people with treatment-naïve CLL who passed pre-trial screening, and we preliminarily conclude that the exercise training program was safe and also resulted in an increase in lean mass.Clinical trial registrationhttps://doi.org/10.1186/ISRCTN55166064, identifier ISRCTN 55166064.

Durable antitumor response via an oncolytic virus encoding decoy-resistant IL-18

BackgroundInterleukin-18 (IL-18), or interferon (IFN)-γ-inducing factor, potentiates T helper 1 and natural killer cell activation as well as CD8+ T-cell proliferation. Recombinant IL-18 has displayed limited clinical efficacy in part...

Smooth muscle-specific deletion of cellular communication network factor 2 causes severe aorta malformation and atherosclerosis.

Cellular communication network factor 2 (CCN2) is a matricellular protein implicated in fibrotic diseases, with ongoing clinical trials evaluating anti-CCN2-based therapies. By uncovering CCN2 as abundantly expressed in non-diseased artery tissue, this study aimed to investigate the hypothesis that CCN2 plays a pivotal role in maintaining smooth muscle cell (SMC) phenotype and protection against atherosclerosis. Global- and SMC-specific Ccn2 knockout mouse models were employed to demonstrate that Ccn2 deficiency leads to SMC de-differentiation, medial thickening, and aorta elongation under normolipidaemic conditions. Inducing hyperlipidaemia in both models resulted in severe aorta malformation and a 17-fold increase in atherosclerosis formation. Lipid-rich lesions developed at sites of the vasculature typically protected from atherosclerosis development by laminar blood flow, covering 90% of aortas and extending to other vessels, including coronary arteries. Evaluation at earlier time points revealed medial lipid accumulation as a lesion-initiating event. Fluorescently labelled LDL injection followed by confocal microscopy showed increased LDL retention in the medial layer of Ccn2 knockout aortas, likely attributed to marked proteoglycan enrichment of the medial extracellular matrix. Analyses leveraging data from the Athero-Express study cohort indicated the relevance of CCN2 in established human lesions, as CCN2 correlated with SMC marker transcripts across 654 transcriptomically profiled carotid plaques. These findings were substantiated through in situ hybridization showing CCN2 expression predominantly in the fibrous cap. This study identifies CCN2 as a major constituent of the normal artery wall, critical in regulating SMC differentiation and aorta integrity and possessing a protective role against atherosclerosis development. These findings underscore the need for further investigation into the potential effects of anti-CCN2-based therapies on the vasculature.

Arrayed CRISPR libraries for the genome-wide activation, deletion and silencing of human protein-coding genes.

Arrayed CRISPR libraries extend the scope of gene-perturbation screens to non-selectable cell phenotypes. However, library generation requires assembling thousands of vectors expressing single-guide RNAs (sgRNAs). Here, by leveraging massively parallel plasmid-cloning methodology, we show that arrayed libraries can be constructed for the genome-wide ablation (19,936 plasmids) of human protein-coding genes and for their activation and epigenetic silencing (22,442 plasmids), with each plasmid encoding an array of four non-overlapping sgRNAs designed to tolerate most human DNA polymorphisms. The quadruple-sgRNA libraries yielded high perturbation efficacies in deletion (75-99%) and silencing (76-92%) experiments and substantial fold changes in activation experiments. Moreover, an arrayed activation screen of 1,634 human transcription factors uncovered 11 novel regulators of the cellular prion protein PrPC, screening with a pooled version of the ablation library led to the identification of 5 novel modifiers of autophagy that otherwise went undetected, and 'post-pooling' individually produced lentiviruses eliminated template-switching artefacts and enhanced the performance of pooled screens for epigenetic silencing. Quadruple-sgRNA arrayed libraries are a powerful and versatile resource for targeted genome-wide perturbations.

CD33-CD123 IF-THEN gating reduces toxicity while enhancing the specificity and memory phenotype of AML-targeting CAR-T cells.

CAR T-cell therapy has remarkably succeeded in treating lymphoblastic leukemia. However, its success in AML remains elusive due to the risk of on-target off-tumor toxicity to hematopoietic stem and progenitor cells (HSPC) and insufficient T-cell persistence and longevity. Using a SynNotch circuit, we generated a high-precision "IF-THEN" gated logical circuit against the combination of CD33 and CD123 AML antigens and demonstrated anti-tumor efficacy against AML cell lines and patient-derived xenografts. Unlike constitutively expressed CD123 CAR-T cells, those expressed through the CD33 SynNotch circuit could preserve HSPCs and lower the risk of on-target off-tumor hematopoietic toxicity. These gated CAR-T cells exhibited lower expression of exhaustion markers (PD1, Tim3, LAG3, and CD39), higher frequency of memory T cells (CD62L+CD45RA+), and enhanced expansion. While targeting AML, the moderated circuit CAR signal also helped to mitigate cytokine release syndrome, potentially addressing one of the ongoing challenges in CAR-T immunotherapy.

Prognostic Significance of Biointegration at the Optic-Cornea Joint in Keratoprosthesis Implantation.

The purpose of this study was to characterize the morphological and immunological aspects of biointegration at the optic-cornea joint of a second-generation synthetic corneal device. The initial prototype, single-piece optic-skirt configuration, is constructed from compact and flexible perfluoroalkoxy alkane with porous expanded polytetrafluoroethylene (ePTFE) overlying the skirt to allow skirt-cornea biointegration. The second-generation version was modified to add ePTFE around the optic wall to allow optic-cornea biointegration. Initial and amended second-generation devices were implanted into healthy rabbit eyes. Clinical examination, anterior segment optical coherence tomography, light microscopy, and immunofluorescence studies were performed to assess structural integrity and determine molecular signatures indicative of inflammation and tissue remodeling between the 2 prototypes. Recipient eyes with both device versions showed no epithelial defects or tissue retraction at 3 months postoperatively. Optical coherence tomography images demonstrated no appreciable perioptic space with either prototype. Histopathology of the initial device demonstrated lack of stromal adhesion at the optic-cornea joint with epithelium filling the perioptic space. Second-generation devices demonstrated full sealing of the recipient stroma along the optic stem. Although the routine histopathology did not demonstrate inflammatory cells in the recipient cornea with either device, immunohistochemistry stains demonstrated quiescent phenotype of stromal and epithelial cells only in the second-generation devices. Biointegration between the synthetic corneal device and recipient tissue at the optic-cornea joint seems to avert inflammation and may help prevent sterile tissue lysis and prolong retention.

Genetic insights into the effect of trace elements on cardiovascular diseases: multi-omics Mendelian randomization combined with linkage disequilibrium score regression analysis

ObjectiveEpidemiological evidence indicates that trace elements are significantly associated with cardiovascular health. However, its causality and underlying mechanisms remain unclear. Therefore, this study aimed to investigate the causal relationship between trace elements and cardiovascular disease, as well as their potential mechanism of action.MethodTwo-sample Mendelian randomization (MR) analyses along with mediated and multivariate MR analyses were employed. These analyses utilized 13 trace elements as exposure variables and 20 cardiovascular diseases as outcome variables, with 4907 circulating plasma proteins, 1400 serum metabolites, 731 immune cell phenotypes, and 473 intestinal flora as potential mediators. The Bayesian weighted MR method was used to validate the MR results, and linkage disequilibrium score regression (LDSC) was applied to explore the genetic correlation between trace elements and cardiovascular disease.ResultOur findings indicated a positive or negative causal relationship between genetically predicted trace elements and cardiovascular disease. An analysis using the Bayesian weighted MR method demonstrated that our causal inference results were reliable. The results of the mediated MR analyses indicate that potassium may reduce the risk of ischemic heart disease by influencing the expression of the plasma proteins BDH2 and C1R. Vitamin B12 may increase the risk of coronary atherosclerosis and cardiovascular death by reducing the levels of VPS29 and PSME1 proteins, while vitamin C may mitigate the risk of cardiac arrest by inhibiting the expression of the TPST2 protein. In addition, potassium can reduce the risk of ischemic heart disease by lowering 4-methoxyphenyl sulfate levels. None of the instrumental variables exhibited pleiotropy in the MR analysis. A sensitivity analysis using the leave-one-out method further confirmed the robustness of our findings. LDSC results indicated a genetic correlation between multiple trace elements and various cardiovascular diseases.ConclusionThis study uncovered the true causal relationship between trace elements and cardiovascular disease risk using genetic methods, and revealed the significant mediating role of specific plasma proteins and metabolites in this relationship.

Natural Killer Cell Phenotypes and Clinical Outcomes in Pediatric Kidney Transplantation.

Natural killer (NK) cells have gained recognition for playing an integral role in both alloimmunity and protective immunity, particularly viral infection control, in solid organ transplantation. Using data from the Clinical Trials in Organ Transplantation in Children (CTOTC) study entitled, "Immune Development in Pediatric Transplantation," (NCT00951353), we aimed to identify NK cell phenotypes that were associated with viral infection versus alloreactive events during the first year after transplantation. We also examined the relationship between NK cells with 7-year patient and allograft survival using the Scientific Registry for Transplant Recipients (SRTR) database. A secondary analysis of peripheral blood mononuclear cells from 98 children aged 1-20 years old with kidney transplants was conducted using multiparameter flow cytometry for the following NK cell phenotypes: CD56bright, CD56dim, and CD56negative. We associated these phenotypes with either viral infection or alloimmunity (de novo donor-specific antibody (dnDSA) development or acute rejection), using Fine-Gray subdistribution hazard models for competing risks. Secondary outcomes included allograft and patient survival. We demonstrated that specific baseline NK cell phenotypes obtained prior to transplantation may be associated with either viral infection or alloimmunity. An elevation in CD56dim frequency was associated with an increased risk of infection, while an increase in CD56negative absolute count was associated with an increased risk of an alloimmune event. NK cells were not associated with graft survival. NK cell phenotyping may be a useful tool to help differentiate infectious from alloimmune risk.

MicroRNA-18a-5p promotes vascular smooth muscle cell phenotypic switch by targeting Notch2 as therapeutic targets in vein grafts restenosis

Vascular smooth muscle cells (VSMCs) phenotype switching plays a crucial role in vein graft restenosis following coronary artery bypass grafting (CABG) surgery. To discover novel clinically relevant therapeutic targets for vein graft restenosis after CABG, we therefore investigated whether miRNA-18a-5p mediated phenotype switching plays a critical role in the development of vein graft restenosis. We studied miRNA-18a-5p expression in plasma samples of patients with or without vein graft restenosis at 1, 3 and 5 years after coronary artery bypass graft surgery, and in normal vs. atherosclerotic human femoral artery samples, to prove its role in VSMC phenotype switching. We found that the expression of miRNA-18a-5p significantly increased in vein grafts restenosis rat model after bypass surgery at 7, 14, 28 days and human blood specimens with vein grafts failure after grafting surgery. Through gain- and loss-of-function approaches, we determined that miRNA-18a-5p affects VSMC proliferation, migration, differentiation, and contractility. Notch2 was found to be a direct target of miRNA-18a-5p, which is critical for VSMC phenotype switching. Finally, miRNA-18a-5p knockdown used miRNA sponge via AAV6 locally delivery in vivo, miRNA-18a-5p sponge gene transfer therapy reduced the neointimal area, neointimal thickness, and intimal/media area ratio in vein grafts compared with the controls and improved vein graft hemodynamics. miRNA-18a-5p is a critical modulator of VSMC phenotypic switch during development of vein graft restenosis by downregulating Notch2, therefore targeting miRNA-18a-5p may be a helpful strategy for the treatment of vein grafts restenosis or failure after CABG surgery.

Spinal AT1R contributes to neuroinflammation and neuropathic pain via NOX2-dependent redox signaling in microglia

Microglia-mediated neuroinflammation demonstrates a crucial act in the progression of neuropathic pain. Oxidative damage induced by reactive oxygen species (ROS) derived from NADPH oxidase (NOX) in microglia drives proinflammatory microglia activation. Recent evidence points to the central renin angiotensin system (RAS) is involved in oxidative stress and neuroinflammation, with the angiotensin converting enzyme/angiotensin II/angiotensin receptor-1 (ACE/Ang II/AT1R) axis promoting inflammation through increased ROS production, counteracted by the ACE2/Ang (1-7)/ Mas receptor (MasR) axis. While interventions targeting spinal AT1R have been shown to alleviate nociceptive hypersensitivity; yet the mechanisms remain elusive. Here, we discovered that spared nerve injury (SNI)-induced mechanical allodynia in rats were associated with M1-like microglia activation, oxidative stress and overactivity of ACE/Ang II/AT1R axis in the spinal cord. Increased AT1R and NOX2 expression were observed in activated dorsal horn microglia following SNI. Blockade of AT1R with losartan potassium (LOP) suppressed NOX2-mediated oxidative stress, and promoted a shift in microglia from the proinflammatory M1 phenotype to the anti-inflammatory M2 phenotype in LPS-treated BV-2 cells. Additionally, NOX2 overexpression triggered the activation of the high-mobility group box 1/ nuclear factor-kappa B (HMGB1/NF-κB) signaling pathway. Intrathecal administration of LOP effectively inhibited SNI-induced NOX2 overactivation in microglia and suppressed the HMGB1/NF-kB pathway, reducing oxidative stress and shifting the microglia polarization from M1 to M2 in the spinal cord, thereby attenuating neuroinflammation and pain hypersensitivity. Collectively, these findings underscore the neuroimmune-modulating effects of spinal AT1R in neuropathic pain, highlighting the regulation of redox homeostasis in microglia via a NOX2 dependent mechanism.