Different Stages Of Differentiation Research Articles

Current progress in chimeric antigen receptor T‐cell therapy for malignant tumors

AbstractIn the realm of malignant tumor treatment, particularly regarding hematologic malignancies, chimeric antigen receptor T‐cell (CAR‐T) immunotherapy has witnessed remarkable advancements in recent years. This approach involves genetically modifying and engineering a patient's T‐cells ex vivo to express a specific CAR, known as CAR‐T cells. When these modified cells are reintroduced into the patient, they can specifically recognize target antigens and exhibit highly efficient cytotoxicity against cells expressing these antigens, making them suitable for the treatment of malignant tumors. CD19, which is expressed on the surface of B lymphocytes at different stages of differentiation, has been identified as a suitable target for the treatment of most B‐cell lymphomas. CAR‐T cells targeting CD19 have demonstrated excellent specificity, cytotoxicity, and persistence in both in vitro and clinical trials, showing tremendous potential for application. However, identifying appropriate targets for CAR‐T therapy in solid tumors remains a challenge, leading to limited advancements in this area. This review discusses the mechanisms, applications, limitations, and prospects of CAR‐T therapy in hematologic malignancies and solid tumors, aiming to provide directions for future research in this field.

RNA-Mediated Regulation of Glycolysis in Embryonic Stem Cell Pluripotency and Differentiation

Abstract Purpose of Review The maintenance and differentiation of embryonic stem cells are strictly coordinated with their metabolic status. As a core part of cellular metabolism, glycolysis provides energy and biomolecules important for stem cell proliferation and functions. Particularly, the differentiation of embryonic stem cells is associated with metabolic shifts between glycolysis and oxidative phosphorylation. However, how these metabolic swifts are regulated is still not completely known. This review aims to highlight recent advances in regulation of glycolysis at different stages of embryonic stem cells. Recent Findings Through modulating glycolysis, multiple types of RNA molecules and RNA-binding proteins are critically involved in regulation of the self-renewal, pluripotency, and differentiation of embryonic stem cells. Summary RNA-mediated glycolytic regulation in embryonic stem cells is important for their maintenance and transitions between different stages of differentiation. Better understanding of these riboregulatory mechanisms will have potential for future research and therapeutic innovation.

Reciprocal negative feedback between Prrx1 and miR-140-3p regulates rapid chondrogenesis in the regenerating antler

During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair.

Brain neurotrophic factor BDNF: new data, functions and questions

The brain-derived neurotrophic factor (BDNF) is a key modulator of neurogenesis, synaptogenesis, neuroregeneration, and cell differentiation in the nervous system. Impaired BDNF functioning is a characteristic of various neurological diseases, such as Alzheimer’s disease, multiple sclerosis, and depressive disorders. There is recent evidence that patients with COVID-19 have reduced BDNF levels in the blood plasma. Furthermore, exogenous BDNF and its mimetics have demonstrated therapeutic potential.
 In this review, we systematized data of the BDNF gene structure, epigenetic and microRNA-mediated regulation of its expression, transcriptional variants of BDNF, and the effects of BDNF on neuronal and oligodendroglial differentiation. Further, we point out the gaps in the current knowledge about BDNF and propose experiments that can expand such knowledge and the range of possibilities for using BDNF in biomedicine. These include determining the expression pattern of all BDNF gene transcripts at different stages of differentiation and in different cell subpopulations and studying the role of receptor-independent BDNF signaling, circadian fluctuations in BDNF levels, and their role in physiological and pathophysiological conditions. Finally, for translational medicine, evaluating the effect of BDNF mimetics (including those immobilized on three-dimensional scaffolds for tissue engineering) on neuronal and oligodendroglial differentiation of pluripotent and polypotent cells and identifying molecular regulators of BDNF transcription, including small molecules and microRNAs capable of regulating BDNF gene expression, are crucial.

Noninvasive Assessment of hiPSC Differentiation toward Cardiomyocytes Using Pretrained Convolutional Neural Networks and the Channel Pruning Algorithm.

Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs) offer versatile applications in tissue engineering and drug screening. To facilitate the monitoring of hiPSC cardiac differentiation, a noninvasive approach using convolutional neural networks (CNNs) was explored. HiPSCs were differentiated into cardiomyocytes and analyzed using the quantitative real-time polymerase chain reaction (qRT-PCR). The bright-field images of the cells at different time points were captured to create the dataset. Six pretrained models (AlexNet, GoogleNet, ResNet 18, ResNet 50, DenseNet 121, VGG 19-BN) were employed to identify different stages in differentiation. VGG 19-BN outperformed the other five CNNs and exhibited remarkable performance with 99.2% accuracy, recall, precision, and F1 score and 99.8% specificity. The pruning process was then applied to the optimal model, resulting in a significant reduction of model parameters while maintaining high accuracy. Finally, an automation application using the pruned VGG 19-BN model was developed, facilitating users in assessing the cell status during the myocardial differentiation of hiPSCs.

Abstract 3877: Multi-modal analysis of paracrine signaling in group 3/4 medulloblastoma

Abstract Medulloblastoma (MB) is the most common primary brain malignancy in kids, with the group 3 and 4 subtypes (G3/4) being the most aggressive. Recent single-cell genomics studies have identified the G3/4 MB cell of origin and point to disrupted stem-cell differentiation as a key factor in MB pathogenesis. However, surprisingly little is known about the contribution of tumor-supportive paracrine signaling to the ontogeny of this disease. The spatial organization of MB cellular hierarchies is not completely understood. We profiled N=24 G3/4 MBs from UCSF patients via single-nucleus RNA sequencing (snRNA-seq). Of these cases, N=10 were profiled via single-cell assay for transposase-accessible chromatin by sequencing (scATAC-seq). To capture the spatial context, we profiled an additional 20 samples via spatial transcriptomics using the Visium and Xenium platforms. We found that the standard Xenium brain capture set was inadequate, and we developed a highly specific capture set for G3/4 MBs. In particular, our panel resolves cell-type differences in the stage of MB lineage commitment, from rhombic-lip progenitors to more differentiated unipolar brush-like cells. Altogether, over 110,000 nuclear-sequencing libraries and over 1,898,000 spatially-resolved single-cell libraries were generated. We inferred cell-cell communication signals from our snRNA-seq data by identifying co-expressed receptors and their cognate ligands. We then performed an integrated analysis of our snRNA-seq and scATAC-seq data to infer the cis-regulatory enhancers of those signaling genes, as well as the transcription factors that bind them. We employed our spatial transcriptomics data to confirm paracrine signaling networks inferred from nuclear-sequencing data. We found that distinct MB cell types corresponding to different stages of differentiation occupied specific spatial domains. The results of our ongoing analysis of this spatially-resolved single-cell atlas will be presented. This study paves the way for innovative therapeutic strategies targeting paracrine signaling in G3/4 MB. Citation Format: Bohyeon Yu, Jangham Jung, Aaron Diaz. Multi-modal analysis of paracrine signaling in group 3/4 medulloblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3877.

Screening and identification of lncRNAs in preadipocyte differentiation in sheep

Studies of preadipocyte differentiation and fat deposition in sheep have mainly focused on functional genes, and with no emphasis placed on the role that long non-coding RNAs (lncRNAs) may have on the activity of those genes. Here, the expression profile of lncRNAs in ovine preadipocyte differentiation was investigated and the differentially expressed lncRNAs were screened on day 0 (D0), day 2(D2) and day 8(D8) of ovine preadipocyte differentiation, with their target genes being predicted. The competing endogenous RNA (ceRNA) regulatory network was constructed by GO and KEGG enrichment analysis for functional annotation, and some differentially expressed lncRNAs were randomly selected to verify the RNA-Seq results by RT-qPCR. In the study, a total of 2517 novel lncRNAs and 3943 known lncRNAs were identified from ovine preadipocytes at the three stages of differentiation, with the highest proportion being intergenic lncRNAs. A total of 3455 lncRNAs were expressed at all three stages of preadipocyte differentiation, while 214, 226 and 228 lncRNAs were uniquely expressed at day 0, day 2 and day 8, respectively. By comparing the expression of the lncRNAs between the three stages of differentiation stages, a total of 405, 272 and 359 differentially expressed lncRNAs were found in D0-vs-D2, D0-vs-D8, and D2-vs-D8, respectively. Functional analysis revealed that the differentially expressed lncRNAs were enriched in signaling pathways related to ovine preadipocyte differentiation, such as mitogen-activated protein kinase (MAPK) pathway, the phosphoinositide 3-kinase protein kinase B (PI3K-Akt) pathway, and the transforming growth factor beta (TGF-β) pathway. In summary, lncRNAs from preadipocytes at different stages of differentiation in sheep were identified and screened using RNA-Seq technology, and the regulatory mechanisms of lncRNAs in preadipocyte differentiation and lipid deposition were explored. This study provides a theoretical reference for revealing the roles of lncRNAs in ovine preadipocyte differentiation and also offers a theoretical basis for further understanding the regulatory mechanisms of ovine preadipocyte differentiation.

Субпопуляционный состав T-хелперов у больных острыми лейкозами после трансплантации аллогенных гемопоэтических стволовых клеток

Aim. To identify the characteristics of T-helper subpopulations in healthy donors and to compare them with those reported in acute leukemia patients 6 months after allogeneic hematopoietic stem cell transplantation (allo-HSCT).
 Materials & Methods. The study enrolled 41 blood donors and 49 patients after-HSCT. The median age of donors was 36 years (range 20–60 years), 29 of them were men and 12 were women. The median age of patients was 37 years (range 19–62 years), 18 of them were men and 31 were women. Acute myeloid leukemia was diagnosed in 27 (55 %) patients and acute lymphoblastic leukemia/lymphoma in 22 (45 %) patients. Myeloablative conditioning was administered to 4 (8 %) patients and reduced intensity conditioning to 45 (92 %) patients. T-helper subpopulations were studied in the blood of healthy donors vs. acute leukemia patients after allo-HSCT. The flow cytometry analysis was conducted to simultaneously assess the expression of markers CD3, CD4, CD8, CD25, CD45RA, CD197, CD28, CCR4, CCR6, CCR10, CXCR3, and CXCR5 in T-cells.
 Results. The study demonstrated that the count of T-helpers at different stages of differentiation (regulatory, naive T-cells, memory cells, and effector cells) comprehensively distinguishes healthy donors from patients. Moreover, the functional structure of each of these populations differ in donors vs. patients even on Month +6 after allo-HSCT. Donors appeared to have more polarized cells among the central memory T-helpers. The proportion of T-helpers type 1 among the effector cells was higher is patients.
 Conclusion. The results of the study indicate that the Т-cell parameter set can be analyzed to assess immunity and to describe its disorders in different pathologies or after drug chemotherapy.

Microstructural analysis of meat and internal organs of broiler chickens using a probiotic biological product

Probiotic preparation containing bacteria of the genus Bacillus subtilis and Bacillus licheniformis used for feeding broiler chickens to improve feed digestion, nutrient absorption, increase immune status and productivity, and for the prevention and treatment of various poultry diseases. The purpose of the study is to conduct histological tests of broiler chicken slaughter products when they were administered a probiotic biologic medical product in doses of: 0.5 g, 2.0, and 4.0 g per 10 dm3 of water. The material was examined by the histological method. It was found that the muscle fibres in the pectoralis major are of the same type, evenly directed, the cytoplasm of muscle fibres is moderately eosinophilic, uniformly light pink, and minor layers of adipose tissue are found between the bundles of muscle fibres. The morphological architectonics of the heart muscle are preserved, cardiomyocytes are homogeneous and have a clear orientation. The microstructure of the liver of broiler chickens is unchanged: hepatocytes are collected in the same type of groups; the central veins are desolate; the cytoplasm of these cells is homogeneous, clear, and pink; the nuclei are weakly basophilic. In the spleen, the follicular structure is formed, leukocytes are diffusely placed at different stages of differentiation; vessels in significant numbers, thickened, of different calibre. The cuticle of the muscular part of the stomach contains the epithelial layer, the volume part of the connective tissue base layer is revealed; muscle fibres are located under the mesenchymal base of the cuticle. Lungs by morphological structure have bronchial tubes throughout the structure, which contain blood cells. According to the results of the conducted studies, a beneficial effect of a probiotic biological product at a dose of 4.0 g/10 dm3 of water on the morphology of the pectoralis major and internal organs of broiler chickens was established. Therefore, a probiotic at a dose of 4.0 g/10 dm3 of water during the drinking of broiler chickens can be recommended to increase productivity and produce safe slaughter products. The practical significance of the results obtained is to determine the features of the effect of feeding poultry with different doses of probiotics on the microstructure of its slaughter products, which is important for obtaining the best effect from its use

Engineering a CRISPRoff Platform to Modulate Expression of Myeloid Cell Leukemia (MCL-1) in Committed Oligodendrocyte Neural Precursor Cells.

In vitro differentiation of human pluripotent stem cell (hPSC) model systems has furthered our understanding of human development. Techniques used to elucidate gene function during early development have encountered technical challenges, especially when targeting embryonic lethal genes. The introduction of CRISPRoff by Nuñez and collaborators provides an opportunity to heritably silence genes during long-term differentiation. We modified CRISPRoff and sgRNA Sleeping Beauty transposon vectors that depend on tetracycline-controlled transcriptional activation to silence the expression of embryonic lethal genes at different stages of differentiation in a stable manner. We provide instructions on how to generate sgRNA transposon vectors that can be used in combination with our CRISPRoff transposon vector and a stable hPSC line. We validate the use of this tool by silencing MCL-1, an anti-apoptotic protein, which results in pre-implantation embryonic lethality in mice; this protein is necessary for oligodendrocyte and hematopoietic stem cell development and is required for the in vitro survival of hPSCs. In this protocol, we use an adapted version of the differentiation protocol published by Douvaras and Fossati (2015) to generate oligodendrocyte lineage cells from human embryonic stem cells (hESCs). After introduction of the CRISPRoff and sgRNAs transposon vectors in hESCs, we silence MCL-1 in committed oligodendrocyte neural precursor cells and describe methods to measure its expression. With the methods described here, users can design sgRNA transposon vectors targeting MCL-1 or other essential genes of interest to study human oligodendrocyte development or other differentiation protocols that use hPSC model systems. Key features • Generation of an inducible CRISPRoff Sleeping Beauty transposon system. • Experiments performed in vitro for generation of inducible CRISPRoff pluripotent stem cell line amenable to oligodendrocyte differentiation. • Strategy to downregulate an essential gene at different stages of oligodendrocyte development.

Purification by STA-PUT Technique of Male Germ Cells from Single Mouse and RNA-Extraction for Transcriptomic Analysis.

Transcriptomic analyses of germ cells at different stages of differentiation have shed light on the transcriptional and post-transcriptional mechanisms regulating gene expression that ensure the correct progression of spermatogenesis and male fertility. In this chapter, we describe a method to isolate meiotic and post-meiotic germ cells, based on gravimetric sedimentation, starting from a testicular germ cell suspension isolated from a single adult mouse. We also describe how to assess the purity and quality of the collected fractions of germ cells and how to optimize the extraction from these samples of RNA for subsequent RNA-sequencing experiment. In our experience, this protocol is suitable for germ cell isolation and transcriptomic analysis for mouse models with spermatogenic defects, overcoming the limits that reduced fertility poses to the obtaining of experimental animals.

NR2F1 : A Novel Candidate for Gamma Globin Activation

The reactivation of human gamma globin holds tremendous promise as a potential treatment for hemoglobinopathies, including sickle cell disease and beta-thalassemia. Despite identifying various repressors of fetal globin genes in adult erythroid cells over the past decade, evidence concerning stage-specific factors that activate human fetal globin prior to the switch to adult beta-globin remains inadequately understood. In our study, we constructed an erythroid-specific gene regulatory network (GCN) by integrating multiple RNA-seq datasets from erythroid cells at different stages of differentiation and development. Our analysis unveiled both known HbF activators, like HIC2, and novel candidates. Among the novel contenders, NR2F1, a member of the steroid/thyroid hormone receptor superfamily, emerged as a prominent candidate. To validate our predictions, we overexpressed NR2F1 in Hudep2 cells and observed more than a four-fold increase (28% vs. 6%) in the proportion of F cells and a three-fold rise in HbF levels as measured by HPLC. In addition, the overexpression of NR2F1 did not appear to impact beta-globin expression or cell differentiation. Intriguingly, we observed a significant reduction in the protein level of BCL11A, a master regulator of HbF, despite no major change in the total RNA level of BCL11A. This observation suggests that NR2F1 plays a role in the post-transcriptional modification of BCL11A. Additionally, NR2F1 overexpression led to an upregulation of Lin28B expression in Hudep2 cells. Lin28B is known to directly bind BCL11A mRNA and prevent its effective translation without disturbing BCL11A transcription. Consequently, the observed upregulation of Lin28B in NR2F1-overexpressing cells implies a potential NR2F1-Lin28B-BCL11A axis involved in controlling human hemoglobin switching. In conclusion, our findings propose NR2F1 as a novel activator of gamma globin, representing an attractive target for gamma globin reactivation. Additional investigation is required to explore the molecular mechanisms through which NR2F1 regulates gamma globin expression and its role in the NR2F1-Lin28B-BCL11A axis.

HIF-1 regulates common bidirectional gene expression changes during hypoxia and iron deficiency in human induced pluripotent stem cell derived cardiomyocytes

Abstract Background Heart failure regardless of cause is characterised by extensive transcriptional reprogramming and a switch to foetal developmental programmes via unknown mechanisms (1-3). An additional factor that adversely impacts heart failure patients is iron deficiency (ID)(4). ID is also associated with worse prognosis in acute coronary syndromes (5). However, the mechanisms by which ID interferes with clinical outcomes in heart disease remain incompletely understood. Purpose The purpose of this study was to investigate gene expression changes in human cardiomyocytes during hypoxia and ID, two important stressors in the context of ischaemia and heart failure. Methods In this study, we use human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) derived through a protocol that promotes left ventricle cardiomyocyte differentiation (6). Cells were harvested at different stages of differentiation (day 6 and day 32) and mature (day 32) hiPSC-CMs were treated with 30 μM deferoxamine to induce ID either under normoxic or hypoxic conditions with 1% O2. hiPSC contraction was assessed using musclemotion software and metabolism through use of a Seahorse extracellular flux analyser. RNA was isolated using standard isolation kits and RNA-seq (n=5) was performed. Data was analysed for gene expression by alignment with the human hg19 reference genome using the software STAR. A log2 fold change of 1 and P value of <0.0001 were considered significant. Results We show that both hypoxic and ID hiPSC-CMs demonstrate impaired contractility and reduced oxygen consumption, features of cardiomyocytes from failing hearts. Importantly, hiPSC-CMs exposed to hypoxia, ID or the combination of the two exhibit bidirectional gene expression changes with significant overlap (Figure 1). Focusing on the commonly affected gene set, it becomes evident that hypoxia & ID work via similar mechanisms involving activation of the HIF-1 pathway, that in turn orchestrates the metabolic switch to glycolysis and glutamine oxidation similar to foetal cells. Overall, hypoxia promotes a shift towards immature gene programmes, with 45% of dysregulated genes in hypoxia mimicking expression patterns of less mature cells. Interestingly changes in long non-coding RNA (lncRNA) profiles in hypoxia and ID mimic gene expression changes in these conditions (figure 2). Although restoring oxygen levels in hypoxic hiPSC-CMs rescues the hypoxic transcriptional signature, hiPSC-CMs previously exposed to hypoxia can use glycolytic pathways more efficiently upon further exposures to hypoxia. Conclusion These results shed light into the mechanisms ID impacts heart disease patients and are suggestive that HIF-1 is a key player in orchestrating the gene switch in ID and hypoxia.

Integrative genome-scale analyses reveal post-transcriptional signatures of early human small intestinal development in a directed differentiation organoid model

BackgroundMicroRNAs (miRNAs) are important post-transcriptional gene regulators controlling cellular lineage specification and differentiation during embryonic development, including the gastrointestinal system. However, miRNA-mediated regulatory mechanisms involved in early embryonic development of human small intestine (SI) remains underexplored. To explore candidate roles for miRNAs in prenatal SI lineage specification in humans, we used a multi-omic analysis strategy in a directed differentiation model that programs human pluripotent stem cells toward the SI lineage.ResultsWe leveraged small RNA-seq to define the changing miRNA landscape, and integrated chromatin run-on sequencing (ChRO-seq) and RNA-seq to define genes subject to significant post-transcriptional regulation across the different stages of differentiation. Small RNA-seq profiling revealed temporal dynamics of miRNA signatures across different developmental events of the model, including definitive endoderm formation, SI lineage specification and SI regional patterning. Our multi-omic, integrative analyses showed further that the elevation of miR-182 and reduction of miR-375 are key events during SI lineage specification. We demonstrated that loss of miR-182 leads to an increase in the foregut master marker SOX2. We also used single-cell analyses in murine adult intestinal crypts to support a life-long role for miR-375 in the regulation of Zfp36l2. Finally, we uncovered opposing roles of SMAD4 and WNT signaling in regulating miR-375 expression during SI lineage specification. Beyond the mechanisms highlighted in this study, we also present a web-based application for exploration of post-transcriptional regulation and miRNA-mediated control in the context of early human SI development.ConclusionThe present study uncovers a novel facet of miRNAs in regulating prenatal SI development. We leveraged multi-omic, systems biology approaches to discover candidate miRNA regulators associated with early SI developmental events in a human organoid model. In this study, we highlighted miRNA-mediated post-transcriptional regulation relevant to the event of SI lineage specification. The candidate miRNA regulators that we identified for the other stages of SI development also warrant detailed characterization in the future.

Infections after chimeric antigen receptor (CAR)-T-cell therapy for hematologic malignancies.

Chimeric antigen receptor (CAR)-T-cell therapies have revolutionized the management of acute lymphoblastic leukemia, non-Hodgkin lymphoma, and multiple myeloma but come at the price of unique toxicities, including cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, and long-term "on-target off-tumor" effects. All of these factors increase infection risk in an already highly immunocompromised patient population. Indeed, infectious complications represent the key determinant of non-relapse mortality after CAR-T cells. The temporal distribution of these risk factors shapes different infection patterns early versus late post-CAR-T-cell infusion. Furthermore, due to the expression of their targets on B lineage cells at different stages of differentiation, CD19, and B-cell maturation antigen (BCMA) CAR-T cells induce distinct immune deficits that could require different prevention strategies. Infection incidence is the highest during the first month post-infusion and subsequently decreases thereafter. However, infections remain relatively common even a year after infusion. Bacterial infections predominate early after CD19, while a more equal distribution between bacterial and viral causes is seen after BCMA CAR-T-cell therapy, and fungal infections are universally rare. Cytomegalovirus (CMV) and other herpesviruses are increasingly breported, but whether routine monitoring is warranted for all, or a subgroup of patients, remains to be determined. Clinical practices vary substantially between centers, and many areas of uncertainty remain, including CMV monitoring, antibacterial and antifungal prophylaxis and duration, use of immunoglobulin replacement therapy, and timing of vaccination. Risk stratification tools are available and may help distinguish between infectious and non-infectious causes of fever post-infusion and predict severe infections. These tools need prospective validation, and their integration in clinical practice needs to be systematically studied.

Human muscle cells sensitivity to chikungunya virus infection relies on their glycolysis activity and differentiation stage

Changes to our environment have led to the emergence of human pathogens such as chikungunya virus. Chikungunya virus infection is today a major public health concern. It is a debilitating chronic disease impeding patients' mobility, affecting millions of people. Disease development relies on skeletal muscle infection. The importance of skeletal muscle in chikungunya virus infection led to the hypothesis that it could serve as a viral reservoir and could participate to virus persistence. Here we questioned the interconnection between skeletal muscle cells metabolism, their differentiation stage and the infectivity of the chikungunya virus. We infected human skeletal muscle stem cells at different stages of differentiation with chikungunya virus to study the impact of their metabolism on virus production and inversely the impact of virus on cell metabolism. We observed that chikungunya virus infectivity is cell differentiation and metabolism-dependent. Chikungunya virus interferes with the cellular metabolism in quiescent undifferentiated and proliferative muscle cells. Moreover, activation of chikungunya infected quiescent muscle stem cells, induces their proliferation, increases glycolysis and amplifies virus production. Therefore, our results showed that Chikungunya virus infectivity and the antiviral response of skeletal muscle cells relies on their energetic metabolism and their differentiation stage. Then, muscle stem cells could serve as viral reservoir producing virus after their activation.

Resistance to CLnA-induced ferroptosis is acquired in Caco-2 cells upon differentiation

In contrast to canonical ferroptosis inducers, highly peroxidable conjugated linolenic acids (CLnA) directly fuel the lipid peroxidation cascade upon their incorporation into membrane phospholipids. Little is known, however, about the cytotoxicity level of CLnAs to normal epithelial cells. Caco-2 cells, derived from colorectal adenocarcinoma, spontaneously differentiate into enterocyte-like cells over a period of 21 days of cell culturing, allowing for graduated phenotypic shift from proliferative, undifferentiated cells to a functional intestinal barrier. We exploited this property to assess the sensitivity of Caco-2 cells to CLnAs at different stages of differentiation. Our results show a significant decrease in CLnA-induced ferroptotic cell death over time. The acquired resistance aligned with decreases in cell proliferation and in the extent of lipid peroxidation, as well as with an increase in the expression of GPX4 upon differentiation. These results highlight that while CLnAs are highly toxic for proliferating cancer cells, differentiated epithelial cells are resistant to CLnA-induced ferroptosis. Therefore, this study gives credential to the therapeutic use of CLnAs as an anticancer strategy and offers a new model study to further investigate the safety of peroxidable fatty acids in differentiated cells.

Single-cell sequencing on CD8+ TILs revealed the nature of exhausted T cells recognizing neoantigen and cancer/testis antigen in non-small cell lung cancer

BackgroundCD8+tumor infiltrating lymphocytes (TILs) are often observed in non-small cell lung cancers (NSCLC). However, the characteristics of CD8+ TILs, especially T-cell populations specific for tumor antigens, remain poorly understood.MethodsHigh throughput...

Toward Corneal Limbus In Vitro Model: Regulation of hPSC-LSC Phenotype by Matrix Stiffness and Topography During Cell Differentiation Process.

A functional limbal epithelial stem cells (LSC) niche is a vital element in the regular renewal of the corneal epithelium by LSCs and maintenance of good vision. However, little is known about its unique structure and mechanical properties on LSC regulation, creating a significant gap in development of LSC-based therapies. Herein, the effect of mechanical and architectural elements of the niche on human pluripotent derived LSCs (hPSC-LSC) phenotype and growth is investigated in vitro. Specifically, three formulations of polyacrylamide gels with different controlled stiffnesses are used for culture and characterization of hPSC-LSCs from different stages of differentiation. In addition, limbal mimicking topography in polydimethylsiloxane is utilized for culturing hPSC-LSCs at early time point of differentiation. For comparison, the expression of selected key proteins of the corneal cells is analyzed in their native environment through whole mount staining of human donor corneas. The results suggest that mechanical response and substrate preference of the cells is highly dependent on their developmental stage. In addition, data indicate that cells may carry possible mechanical memory from previous culture matrix, both highlighting the importance of mechanical design of a functional in vitro limbus model.

Cell metabolism-based optimization strategy of CAR-T cell function in cancer therapy.

Adoptive cell therapy (ACT) using chimeric antigen receptor (CAR)-modified T cells has revolutionized the field of immune-oncology, showing remarkable efficacy against hematological malignancies. However, its success in solid tumors is limited by factors such as easy recurrence and poor efficacy. The effector function and persistence of CAR-T cells are critical to the success of therapy and are modulated by metabolic and nutrient-sensing mechanisms. Moreover, the immunosuppressive tumor microenvironment (TME), characterized by acidity, hypoxia, nutrient depletion, and metabolite accumulation caused by the high metabolic demands of tumor cells, can lead to T cell "exhaustion" and compromise the efficacy of CAR-T cells. In this review, we outline the metabolic characteristics of T cells at different stages of differentiation and summarize how these metabolic programs may be disrupted in the TME. We also discuss potential metabolic approaches to improve the efficacy and persistence of CAR-T cells, providing a new strategy for the clinical application of CAR-T cell therapy.