single-cell sequencing
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Single-cell RNA-seq methods can be used to delineate cell types and states at unprecedented resolution but do little to explain why certain genes are expressed. Single-cell ATAC-seq and multiome (ATAC + RNA) have emerged to give a complementary view of the cell state. It is however unclear what additional information can be extracted from ATAC-seq data besides transcription factor binding sites. Here, we show that ATAC-seq telomere-like reads counter-inituively cannot be used to infer telomere length, as they mostly originate from the subtelomere, but can be used as a biomarker for chromatin condensation. Using long-read sequencing, we further show that modern hyperactive Tn5 does not duplicate 9 bp of its target sequence, contrary to common belief. We provide a new tool, Telomemore, which can quantify nonaligning subtelomeric reads. By analyzing several public datasets and generating new multiome fibroblast and B-cell atlases, we show how this new readout can aid single-cell data interpretation. We show how drivers of condensation processes can be inferred, and how it complements common RNA-seq-based cell cycle inference, which fails for monocytes. Telomemore-based analysis of the condensation state is thus a valuable complement to the single-cell analysis toolbox.
- MeSH
- analýza jednotlivých buněk * metody MeSH
- B-lymfocyty metabolismus cytologie MeSH
- buněčný cyklus * genetika MeSH
- ChiP sekvenování metody MeSH
- chromatin * metabolismus chemie genetika MeSH
- fibroblasty metabolismus cytologie MeSH
- lidé MeSH
- sekvenování transkriptomu metody MeSH
- telomery * genetika MeSH
- vazebná místa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Early identification of resistant cancer cells is currently a major challenge, as their expansion leads to refractoriness. To capture the dynamics of these cells, we made a comprehensive analysis of disease progression and treatment response in a chronic lymphocytic leukemia (CLL) patient using a combination of single-cell and bulk genomic methods. At diagnosis, the patient presented with unfavorable genetic markers, including notch receptor 1 (NOTCH1) mutation and loss(11q). The initial and subsequent treatment lines did not lead to a durable response and the patient developed refractory disease. Refractory CLL cells featured substantial dysregulation in B-cell phenotypic markers such as human leukocyte antigen (HLA) genes, immunoglobulin (IG) genes, CD19 molecule (CD19), membrane spanning 4-domains A1 (MS4A1; previously known as CD20), CD79a molecule (CD79A) and paired box 5 (PAX5), indicating B-cell de-differentiation and disease transformation. We described the clonal evolution and characterized in detail two cell populations that emerged during the refractory disease phase, differing in the presence of high genomic complexity. In addition, we successfully tracked the cells with high genomic complexity back to the time before treatment, where they formed a rare subpopulation. We have confirmed that single-cell RNA sequencing enables the characterization of refractory cells and the monitoring of their development over time.
Single-cell transcriptomics has emerged as a powerful tool to investigate cells' biological landscape and focus on the expression profile of individual cells. Major advantage of this approach is an analysis of highly complex and heterogeneous cell populations, such as a specific subpopulation of T helper cells that are known to differentiate into distinct subpopulations. The need for distinguishing the specific expression profile is even more important considering the T cell plasticity. However, importantly, the universal pipelines for single-cell analysis are usually not sufficient for every cell type. Here, the aims are to analyze the diversity of T cell phenotypes employing classical in vitro cytokine-mediated differentiation of human T cells isolated from human peripheral blood by single-cell transcriptomic approach with support of labelled antibodies and a comprehensive bioinformatics analysis using combination of Seurat, Nebulosa, GGplot and others. The results showed high expression similarities between Th1 and Th17 phenotype and very distinct Th2 expression profile. In a case of Th2 highly specific marker genes SPINT2, TRIB3 and CST7 were expressed. Overall, our results demonstrate how donor difference, Th plasticity and cell cycle influence the expression profiles of distinct T cell populations. The results could help to better understand the importance of each step of the analysis when working with T cell single-cell data and observe the results in a more practical way by using our analyzed datasets.
Current European/US guidelines recommend that molecular testing in advanced non-small cell lung cancer (aNSCLC) be performed using next-generation sequencing (NGS). However, the global uptake of NGS is limited, largely owing to reimbursement constraints. We compared real-world costs of NGS and single-gene testing (SGT) in nonsquamous aNSCLC. This observational study was conducted across 10 pathology centers in 10 different countries worldwide. Biomarker data collected via structured questionnaires (1 January-31 December 2021) were used to feed micro-costing analyses for three scenarios ['Starting Point' (SP; 2021-2022), 'Current Practice' (CP; 2023-2024), and 'Future Horizons' (FH; 2025-2028)] in both a real-world model, comprising all biomarkers tested by each center, and a standardized model, comprising the same sets of biomarkers across centers. Testing costs (including retesting) encompassed personnel costs, consumables, equipment, and overheads. Overall, 4,491 patients with aNSCLC were evaluated. Mean per-patient costs decreased for NGS relative to SGT over time, with real-world model costs 18% lower for NGS than for SGT in the SP scenario, and 26% lower for NGS than for SGT in the CP scenario. Mean per-biomarker costs also decreased over time for NGS relative to SGT. In the standardized model, the tipping point for the minimum number of biomarkers required for NGS to result in cost savings (per patient) was 10 and 12 in the SP and CP scenarios, respectively. Retesting had a negligible impact on cost analyses, and results were robust to variation in cost parameters. This study provides robust real-world global evidence for cost savings with NGS-based panels over SGT to evaluate predictive biomarkers in nonsquamous aNSCLC when the number of biomarkers to be tested exceeds 10. Widespread adoption of NGS may enable more efficient use of limited healthcare resources.
- MeSH
- analýza nákladů a výnosů MeSH
- genetické testování ekonomika metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádorové biomarkery * genetika MeSH
- nádory plic * genetika patologie diagnóza MeSH
- náklady na zdravotní péči MeSH
- nemalobuněčný karcinom plic * genetika diagnóza patologie MeSH
- senioři MeSH
- vysoce účinné nukleotidové sekvenování * ekonomika MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- pozorovací studie MeSH
- srovnávací studie MeSH
Single-cell RNA sequencing (scRNA-seq) methods are widely used in life sciences, including immunology. Typical scRNA-seq analysis pipelines quantify the abundance of particular transcripts without accounting for alternative splicing. However, a well-established pan-leukocyte surface marker, CD45, encoded by the PTPRC gene, presents alternatively spliced variants that define different immune cell subsets. Information about some of the splicing patterns in particular cells in the scRNA-seq data can be obtained using isotype-specific DNA oligo-tagged anti-CD45 antibodies. However, this requires generation of an additional sequencing DNA library. Here, we present IDEIS, an easy-to-use software for CD45 isoform quantification that uses single-cell transcriptomic data as the input. We showed that IDEIS accurately identifies canonical human CD45 isoforms in datasets generated by 10× Genomics 5' sequencing assays. Moreover, we used IDEIS to determine the specificity of the Ptprc splicing pattern in mouse leukocyte subsets.
- MeSH
- alternativní sestřih MeSH
- analýza jednotlivých buněk metody MeSH
- antigeny CD45 * genetika metabolismus MeSH
- leukocyty metabolismus imunologie MeSH
- lidé MeSH
- myši MeSH
- protein - isoformy genetika MeSH
- sekvenční analýza RNA metody MeSH
- software * MeSH
- stanovení celkové genové exprese metody MeSH
- transkriptom MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Genotypic and morphological diversity of cyanobacteria in the Rupite hot spring (Bulgaria) was investigated by means of optical microscopy, cultivation, single-cell PCR, and 16S rRNA gene amplicon sequencing. Altogether, 34 sites were investigated along the 71-39 °C temperature gradient. Analysis of samples from eight representative sites shown that Illumina, optical microscopy, and Roche 454 identified 72, 45 and 19% respective occurrences of all cumulatively present taxa. Optical microscopy failed to detect species of minor occurrence; whereas, amplicon sequencing technologies suffered from failed primer annealing and the presence of species with extensive extracellular polysaccharides production. Amplicon sequencing of the 16S rRNA gene V5-V6 region performed by Illumina identified the cyanobacteria most reliably to the generic level. Nevertheless, only the combined use of optical microscopy, cultivation and sequencing methods allowed for reliable estimate of the cyanobacterial diversity. Here, we show that Rupite hot-spring system hosts one of the richest cyanobacterial flora reported from a single site above 50 °C. Chlorogloeopsis sp. was the most abundant at the highest temperature (68 °C), followed by Leptolyngbya boryana, Thermoleptolyngbya albertanoae, Synechococcus bigranulatus, Oculatella sp., and Desertifilum sp. thriving above 60 °C, while Leptolyngbya geysericola, Geitlerinema splendidum, and Cyanobacterium aponinum were found above 50 °C.
Hypervariable T cell receptors (TCRs) play a key role in adaptive immunity, recognizing a vast diversity of pathogen-derived antigens. Our ability to extract clinically relevant information from large high-throughput sequencing of TCR repertoires (RepSeq) data is limited, because little is known about TCR-disease associations. We present Antigen-specific Lymphocyte Identification by Clustering of Expanded sequences (ALICE), a statistical approach that identifies TCR sequences actively involved in current immune responses from a single RepSeq sample and apply it to repertoires of patients with a variety of disorders - patients with autoimmune disease (ankylosing spondylitis [AS]), under cancer immunotherapy, or subject to an acute infection (live yellow fever [YF] vaccine). We validate the method with independent assays. ALICE requires no longitudinal data collection nor large cohorts, and it is directly applicable to most RepSeq datasets. Its results facilitate the identification of TCR variants associated with diseases and conditions, which can be used for diagnostics and rational vaccine design.
- MeSH
- adaptivní imunita genetika MeSH
- antigeny virové MeSH
- antigeny MeSH
- hypervariabilní oblasti genetika fyziologie MeSH
- imunoterapie MeSH
- lidé MeSH
- receptory antigenů T-buněk imunologie metabolismus fyziologie MeSH
- sekvenční analýza DNA metody MeSH
- shluková analýza MeSH
- vysoce účinné nukleotidové sekvenování metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
PURPOSE OF REVIEW: Current risk stratification and treatment decision-making for bladder cancer informed by histopathology as well as molecular diagnostics face limitations. This review summarizes recent advancements in single-cell and spatial omics methodologies for understanding bladder cancer biology and their potential impact on development of novel therapeutic strategies. RECENT FINDINGS: Single-cell RNA sequencing and spatial omics techniques offer unprecedented insights into various aspects of tumor microenvironment (TME), bladder cancer heterogeneity, cancer stemness, and cellular plasticity. Studies have identified multiple malignant cell subpopulations within tumors, revealing diverse transcriptional states and clonal evolution. Additionally, intratumor heterogeneity has been linked to tumor progression and therapeutic response. Immune cell composition analysis has revealed immunosuppressive features in the TME, impacting treatment response. Furthermore, studies have elucidated the role of cancer-associated fibroblasts and endothelial cells in shaping the tumor immune landscape and response to therapy. SUMMARY: Single-cell and spatial omics technologies have revolutionized our understanding of bladder cancer biology, uncovering previously unseen complexities. These methodologies provide valuable insights into tumor heterogeneity and microenvironmental interactions, with implications for therapeutic development. However, challenges remain in translating research findings into clinical practice and implementing personalized treatment strategies. Continued interdisciplinary collaboration and innovation are essential for overcoming these challenges and leveraging the full potential of single-cell and spatial omics in improving bladder cancer diagnosis and treatment.
- MeSH
- analýza jednotlivých buněk * metody MeSH
- lidé MeSH
- nádorové mikroprostředí * imunologie MeSH
- nádory močového měchýře * genetika terapie imunologie patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
We aimed to explore the development and cell communication of osteoblasts and osteoclasts with aneuploidy variation in giant cell tumour of bone (GCTB). We predicted the diploid and aneuploid cells in tissue samples using the CopyKAT package. The Monocle2 package was used to analyse differentiation trajectories of aneuploid cells. We used the CellChat package to observe the signalling pathways and ligand-receptor pairs for the two interaction types, "Cell-Cell Contact" and "Secreted Signalling", respectively. A total of 9,117 cells were obtained including eight cell types. Most aneuploid cells were osteoblasts. As the cell differentiation trajectory matured, we found that aneuploid osteoblasts first increased the inflammatory response activity and then enhanced the ability to activate T cells, whereas osteoclasts gradually enhanced the cellular energy metabolism, cell adhesion, cell proliferation and immune response; the activated biological functions were gradually weakened. The analysis by CellChat indicated that CTLA4 or TIGIT might act as important immune checkpoint genes to attenuate the inhibitory effect of aneuploid osteoclasts on NK/T cells, thereby enhancing the activity of NK/T cells. Our study found that both osteoblasts and osteoclasts might be involved in the development of GCTB, which may provide a new direction for the treatment of GCTB.
- MeSH
- analýza jednotlivých buněk * MeSH
- aneuploidie * MeSH
- buněčná diferenciace genetika MeSH
- lidé MeSH
- mezibuněčná komunikace * genetika MeSH
- nádory kostí genetika patologie metabolismus MeSH
- obrovskobuněčný nádor kosti * genetika patologie MeSH
- osteoblasty * metabolismus MeSH
- osteoklasty * metabolismus patologie MeSH
- sekvenční analýza RNA metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Apicomplexa is a diverse phylum comprising unicellular endobiotic animal parasites and contains some of the most well-studied microbial eukaryotes including the devastating human pathogens Plasmodium falciparum and Cryptosporidium hominis. In contrast, data on the invertebrate-infecting gregarines remains sparse and their evolutionary relationship to other apicomplexans remains obscure. Most apicomplexans retain a highly modified plastid, while their mitochondria remain metabolically conserved. Cryptosporidium spp. inhabit an anaerobic host-gut environment and represent the known exception, having completely lost their plastid while retaining an extremely reduced mitochondrion that has lost its genome. Recent advances in single-cell sequencing have enabled the first broad genome-scale explorations of gregarines, providing evidence of differential plastid retention throughout the group. However, little is known about the retention and metabolic capacity of gregarine mitochondria. RESULTS: Here, we sequenced transcriptomes from five species of gregarines isolated from cockroaches. We combined these data with those from other apicomplexans, performed detailed phylogenomic analyses, and characterized their mitochondrial metabolism. Our results support the placement of Cryptosporidium as the earliest diverging lineage of apicomplexans, which impacts our interpretation of evolutionary events within the phylum. By mapping in silico predictions of core mitochondrial pathways onto our phylogeny, we identified convergently reduced mitochondria. These data show that the electron transport chain has been independently lost three times across the phylum, twice within gregarines. CONCLUSIONS: Apicomplexan lineages show variable functional restructuring of mitochondrial metabolism that appears to have been driven by adaptations to parasitism and anaerobiosis. Our findings indicate that apicomplexans are rife with convergent adaptations, with shared features including morphology, energy metabolism, and intracellularity.
