Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “single cell analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources

Protocol to perform integrative analysis of high-dimensional single-cell multimodal data using an interpretable deep learning technique.

The advent of single-cell multi-omics sequencing technology makes it possible for researchers to leverage multiple modalities for individual cells. Here, we present a protocol to perform integrative analysis of high-dimensional single-cell multimodal data using an interpretable deep learning technique called moETM. We describe steps for data preprocessing, multi-omics integration, inclusion of prior pathway knowledge, and cross-omics imputation. As a demonstration, we used the single-cell multi-omics data collected from bone marrow mononuclear cells (GSE194122) as in our original study. For complete details on the use and execution of this protocol, please refer to Zhou et al.1.

Deep Learning↗

CAFs activated by YAP1 upregulate cancer matrix stiffness to mediate hepatocellular carcinoma progression.

BACKGROUND: The stiffness of the matrix is closely related to the progression of hepatocellular carcinoma (HCC). Although direct targeting of stromal rigidity in HCC remains a clinical challenge, cancer-associated fibroblasts (CAFs) are considered key contributors to this process. Given the heterogeneity of CAFs, this study explored the relationship between specific CAF subsets and liver cancer matrix stiffness, aiming to identify novel therapeutic targets for HCC patients. METHODS: Single-cell sequencing datasets were leveraged to identify cell types within liver cancer and characterize the transcriptomic profiles of CAFs. Prognostic analysis, utilizing the Gene Expression Profiling Interactive Analysis (GEPIA) and The Cancer Genome Atlas (TCGA) liver cancer datasets, assessed the correlation between matrix stiffness-related genes and HCC patient outcomes. Pseudo-time analysis was applied to trace the developmental trajectories of CAFs. By calculating intercellular communication probabilities and analyzing transcription factor activity, the functions and interactions of different CAF subsets were elucidated. Gene Ontology (GO) analysis was used to explore the functional roles of CAFs in distinct Yes-associated protein 1 (YAP1) groups. Finally, cellular experiments and animal experiments were further conducted to validate the hypotheses of this study. RESULTS: This study identified CAF subpopulations based on single-cell sequencing data and analyzed transcriptional changes within these subpopulations. Key findings include the identification of collagen type I alpha 1 (COL1A1), collagen type III alpha 1 (COL3A1), and lysyloxidase (LOX) as pivotal node genes during CAF development. Moreover, the expression of matrix stiffness-related genes was inversely correlated with the prognosis of HCC patients. Notably, the YAP1-positive CAF subpopulation emerged as the primary contributor to matrix stiffness in liver cancer. This subpopulation upregulates the expression of matrix stiffness-related genes and promotes tumor progression by activating signaling pathways such as autophagy and GTPase activity regulation. Cellular experiments and animal studies further validated this conclusion. CONCLUSION: This single-cell analysis uncovered the functional roles of CAFs in liver cancer. The YAP1-positive CAF subpopulation, in particular, was shown to contribute to matrix stiffness by upregulating the expression of relevant genes and promoting tumor progression through the activation of specific signaling pathways.

Carcinoma, Hepatocellular↗

Computerized microscopic analysis of prostatic fine needle aspirates. Comparison with breast aspirates.

Computerized image analysis was employed to analyze fine needle aspiration smears of the prostate and breast using both high-resolution images of individual cells and medium-resolution images of scenes and clusters (contextual analysis). A linear discriminant analysis was used to demonstrate the computer's ability to discriminate between benign and malignant categories for both types of tissue. Correct classification as benign or malignant using contextual analysis was achieved in 22 of 26 prostatic aspirates and in 15 of 18 breast aspirates, as determined by comparison with histology. The addition of high-resolution single-cell analysis resulted in correct classification of 24 of 26 prostatic aspirates and all breast aspirates. For virtually all features, the distinction between benign and malignant was more subtle for prostatic than for breast tissue. The data indicate that contextual analysis may be less effective as an adjunct to high-resolution single-cell microscopy of prostatic specimens than it is for breast specimens.

Biopsy, Needle↗

From wild to domestic: Single-cell transcriptomic perspectives on hippocampal regulation and evolution.

How domestication shapes brain evolution remains an open question. In this study, we integrated single-nucleus RNA sequencing (snRNA-seq), population genomics, and machine learning to investigate the hippocampal evolution under domestication. Across-species comparisons revealed that hippocampal cell type profiles are largely conserved across vertebrate species, while supporting the presence of adult hippocampal neurogenesis in birds. We further found that domestication and selective breeding likely influence the cellular composition and molecular regulation of the hippocampus. Our findings provide cellular evidence supporting the hypothesis that domestication affects adult hippocampal neurogenesis. Additionally, we showed that genes associated with neural progenitor cells (NPC) states and cell-marker programs are enriched for signatures of selection. Many of these genes function as regulators of neurogenesis and pathways mediating stress and fear reduction. Specifically, we identified selection at the FKBP5 promoter that may influence its expression in the NPC lineage, potentially contributing to stress-response regulation during domestication. Collectively, these results suggest that domestication is associated with hippocampal remodeling as part of an adaptive response to human-managed environments. This study provides a cellular and genetic perspective on how domestication reshapes the brain and offers a basis for further investigation into the mechanisms of neural evolution within the context of microevolution.

Animals↗

Chemiluminescence microscopy reveals functional heterogeneity in single neutrophils undergoing oxygen burst.

Activated polymorphonuclear leukocytes (PMN) respond to various triggers with an oxygen burst, during which the release of reactive oxygen species (ROS) plays a key role in microbial killing. The biological function of the ROS-associated light emissions is not known. However, this particularly weak cell-derived chemiluminescence (CL) may serve as a parameter for the identification of PMN activation. In this study we describe a novel technique which we termed CL microscopy. A microscope-based low-light image-processing system was applied which was sensitive enough to detect single photons, capable of two-dimensional signal accumulation, and digital image analysis. This technique permitted, for the first time, the visualization of the oxygen burst in single cells. Furthermore, quantitative evaluation of cell-derived luminol-enhanced CL revealed functional heterogeneity. Single-cell investigations of activated living PMN of normal human donors showed clear differences in kinetics and intensity of the oxygen burst related to different stimuli. The chemical agent (phorbol 12-myristate 13-acetate) induced CL in 83% of PMN. In contrast, the complement-mediated phagocytic stimulation by opsonized zymosan gave much higher light intensities of individual cells, but only in part of the PMN population (30%). CL microscopy presents a new and highly sensitive technique with considerable potential for single-cell analysis in immunological research.

Free Radicals↗

Flow cytometric analysis of glucocorticoid receptor using monoclonal antibody and fluoresceinated ligand probes.

Conditions were established for single cell analysis of glucocorticoid receptor (GR) content by flow cytometry using several clones of a human leukemic cell line (CCRF-CEM). These included CEM-7A, 7R, C1, and ICR 27 Tk.3 cells which were examined both by standard [3H]dexamethasone radiometric binding and by two independent flow cytometry assays. The latter involved either mouse monoclonal antibody against GR (GR-MoAb) or fluoresceinated cortisol ligand probes. For CEM-7A, 7R, and C1 cells, there was a correlation between GR-MoAb and radiometrically defined GR values. However, clone ICR-27 Tk.3 with low [3H]dexamethasone binding exhibited the highest GR-MoAb fluorescence. The fluoresceinated cortisol assay correlated with dexamethasone binding values in all four clones. Thus, GR-MoAb identifies the total immunologically reactive GR present, while the fluoresceinated cortisol assay quantifies only the functionally intact GR in terms of its initial binding. Their combined use may reveal the cellular heterogeneity of GR expression and function also in human tumor samples, to which they have been successfully applied. When coupled with DNA counterstaining, GR expression can be related directly to frequently DNA-aneuploid tumor cells and cell cycle distribution.

Antibodies, Monoclonal↗

[Study on sperm quality of males living in cold area].

OBJECTIVE: To investigate the effects on male reproductive function working under cold area. METHODS: After on site investigation, advanced molecular lab analysis-single-cell gel electrophoresis (SCGE) and sperm chromatin structure assay (SCSA) which are combined with semen routine analysis were used to evaluate semen quality and sperm sub-clinical injury. RESULTS: Semen routine analysis showed that the semen parameters of the males working in cold area were within normal range, but level I comet cell percentage in SCGE increased significantly, which was 4.4%, compared to the contrast group (1.9%) with significant difference. During sperm chromatin structure assay parameters, comp alpha t increased, with an average value of 22.26%. The two kinds of results both showed single and double strand breakages in sperm. CONCLUSION: Long-term exposure to cold could induce sperm DNA injury, but not affect sperm quality. The results suggested that it was important to reinforce the reproductive care in males working in cold areas.

Adult↗

Integrated single-cell and spatial transcriptomic analyses reveal malignant epithelial glycolytic heterogeneity and spatial niche remodeling during colorectal cancer progression.

Colorectal cancer (CRC) progression is shaped by metabolic reprogramming and complex interactions within the tumor microenvironment. However, the cellular heterogeneity, spatial organization, and clinical relevance of glycolytic activity in CRC remain incompletely understood. In this study, we integrated single-cell RNA sequencing, bulk transcriptomics, and spatial transcriptomics data to systematically characterize glycolytic heterogeneity in CRC. Glycolytic activity was quantified using five independent scoring methods, consistently showing that epithelial cells exhibited the highest glycolytic activity across the two single-cell cohorts. Stratification of CopyKAT-verified aneuploid malignant epithelial cells into high-glycolysis (HG) and low-glycolysis (LG) subgroups by glycolysis scores revealed that HG cells exhibited higher stemness scores and chromosomal copy number variations. Cell-cell communication analysis revealed that, compared with LG cells, HG cells exhibited increased interaction frequency and strength with immune and stromal populations, indicating enhanced malignant epithelial-microenvironment crosstalk. Spatial transcriptomics analyses further revealed that glycolytic activity varied across normal colorectal tissue, primary CRC, and colorectal liver metastases, accompanied by progressive remodeling of epithelial-associated spatial niches and MIF-mediated intercellular communication. Bulk transcriptomic analysis identified a glycolysis-related prognostic signature with robust predictive performance, which served as an independent prognostic factor for overall survival in CRC cohorts. Collectively, these findings indicate that glycolytic heterogeneity is a key feature of CRC malignant epithelial cells and is closely associated with tumor progression, microenvironmental remodeling, and clinical outcomes.

Humans↗

Single-cell and spatial transcriptomics define a progenitor subpopulation and fibroinflammatory niche at the leading edge of parathyroid carcinoma.

Parathyroid carcinoma (PC) is a rare but clinically aggressive endocrine malignancy with limited treatment options and a poorly defined tumor microenvironment (TME). To elucidate its cellular heterogeneity and spatial architecture, we integrated single-cell and spatial transcriptomic profiling with whole-exome sequencing and multiplex immunohistochemistry on eight parathyroid neoplasm specimens, including PC, parathyroid adenoma, and atypical parathyroid tumor. We identified a distinct progenitor-like endocrine subpopulation (Ca-1) enriched in CDC73-mutant PC, exhibiting stem-like properties, elevated cell cycle activity, and pronounced genomic instability. Spatial mapping revealed that Ca-1 cells preferentially localize at the leading edge, forming a fibroinflammatory niche characterized by the enrichment of inflammatory cancer-associated fibroblasts (iCAFs) and SPP1+ macrophages. Within this niche, the dipeptidyl peptidase 4 (DPP4) is selectively expressed in Ca-1 cells and iCAFs, implicating a potential paracrine axis driving stromal remodeling and immunosuppression. These findings suggest that a spatially organized ecosystem may promote PC progression through TME remodeling and highlight the DPP4-CXCL2 axis as a candidate pathway for future investigation in aggressive parathyroid neoplasms.

Humans↗

Sexing and multiple genotype analysis from a single cell of bovine embryo.

We described a procedure for multiple genotype analysis (determination of sex and of three genetic markers) from a single cell derived from bovine preimplantation embryo. It consists of primer extension preamplification-polymerase chain reaction (PEP-PCR) and subsequent single assay or multiplex PCR. A single blastomere that was isolated by microaspiration from bovine embryos at the 16- to 32-cell stage then was lysed and was subjected to the PEP-PCR. When testing 75 embryos, efficiency of genotyping by standard PCR for kappa-casein, growth hormone (GH) and prolactin (PRL) polymorphic alleles was 91, 88 and 89%, respectively. Sexing efficiency in the multiplex PCR was 91%, based on the amplification of Y-specific locus using kappa-casein internal standard. The microaspiration of a single blastomere was shown not to be invasive for the embryos. It did not alter their development potential in vitro (P > 0.05), as was seen by obtaining a similar percentage of embryos developing further into the blastocyst stage in the group subjected to biopsy (44/75, 59%) and in the control group of embryos (30/50, 60%).

Animals↗

Cell-cell communication by quorum sensing and dimension-reduction.

Several bacterial taxa change their behavior if the population density exceeds a certain threshold. This phenomenon is the consequence of a communication system between the bacteria and is called quorum sensing (QS). Up to now, this phenomenon is mostly modeled at population level. However, new experimental techniques allow for single cell analysis. We introduce a modeling approach for the description of this QS system, including a discussion of the regulatory network and its bistable behavior. Based on this single-cell model we develop and analyze a spatially structured model for a cell population. Special attention is given to the scaling behavior w.r.t. the cell size (leading to an approximation theorem for stationary solutions) and its consequences for the interpretation of cell communication (QS versus diffusion sensing). Concluding, we apply the modeling approach to spatially structured experimental data.

4-Butyrolactone↗

Identification of cryosensitive niches and a targetable FOS/AP‑1 program in the human ovarian cortex by single‑cell and spatial transcriptomics.

BACKGROUND: The ovary is a vital and dynamic reproductive organ. Ovarian tissue cryopreservation (OTC) plays a vital role in preserving female fertility. However, the cellular subtypes most susceptible to cryoinjury and the molecular mechanisms underlying cryopreservation-associated damage remain poorly understood. This study aimed to identify cell populations vulnerable to freezing-thawing and to elucidate the key transcriptomic alterations and signaling pathways associated with ovarian cryoinjury at the single-cell and spatial levels. METHODS: Ovarian cortical tissues from patients undergoing three gender reassignment surgery (GRS) were divided into fresh and vitrification-rapid warming groups. Following collagenase IV digestion, 10x Genomics single-cell RNA-seq was used for dissociated ovarian cell suspensions (27,185 fresh and 25,480 frozen-thawed cells). Eight major cell clusters were identified. Additionally, 110 oocytes (66 fresh, 44 vitrification-rapid warming) were isolated and analyzed using the Smart-seq2 platform. Spatial transcriptomics was performed via BGI Stereo-seq. Molecular validation was performed via β-galactosidase staining, immunofluorescence, and qRT-PCR. RESULTS: Cryopreservation significantly altered the activity of pathways related to focal adhesion, oxidative stress, and apoptosis, particularly in stromal and perivascular cells. The number of FOS-positive perivascular cells was notably increased after vitrification-rapid warming, whereas the number of PTGDS-positive stromal cells decreased. Oocyte analysis revealed that cryopreservation primarily disrupted pathways involved in the cell cycle and meiosis, although the damage was not irreversible, supporting the relative safety of long-term cryostorage. Spatial transcriptomics and functional validation further confirmed the rapid and robust activation of the FOS/AP-1 pathway after vitrification-rapid warming, particularly in perivascular and granulosa cells. Treatment with T-5224 (a FOS/AP-1 inhibitor) significantly rescued the morphology and function of cultured frozen-thawed ovaries. CONCLUSIONS: Stromal and perivascular cells are the main cell types that are sensitive to ovarian cryopreservation. The FOS/AP-1 pathway is markedly activated after, suggesting the exacerbation of metabolic impairment. In oocytes within the ovarian cortex, the cell cycle and meiosis-related physiological processes were the primary processes affected.

Female↗

Very low frequencies of human normal CD34+ haematopoietic progenitor cells express the Wilms' tumour gene WT1 at levels similar to those in leukaemia cells.

The Wilms' tumour gene, WT1, is expressed at high levels in leukaemia cells and plays an important role in leukaemogenesis. WT1 is also expressed in human normal CD34+ bone marrow (BM) cells at about 100 times lower levels than in leukaemia cells. To identify and characterize WT1-expressing cells in CD34+ BM cells, they were sorted into single cells and analysed for WT1 expression using two kinds of single-cell reverse transcriptase polymerase chain reaction (RT-PCR) methods. Using the semiquantitative single-cell polyA-PCR + sequence-specific (SS)-PCR method, WT1 expression was detected in four (1.3%) out of 319 CD34+ BM single cells. To confirm the above results, a single-cell nested sequence-specific (NSS)-RT-PCR method that was less quantitative but more sensitive than the polyA-PCR + SS-PCR method was also performed, and WT1 expression was detected in 15 (1.1%) out of 1315 CD34+ BM single cells. In total, WT1 expression was found in 19 (1.2%) out of 1634 CD34+ BM single cells. No significant differences in the frequencies of WT1-expressing cells were found between CD34+CD38- and CD34+CD38+ BM single cells. Furthermore, WT1-expressing CD34+ BM single cells expressed WT1 at levels similar to those in K562 leukaemia single cells. Analysis of lineage-specific and cell cycle gene expression in WT1-expressing CD34+ BM single cells showed that the WT1 gene could be expressed in both uncommitted, dormant CD34+CD38- and lineage-committed, proliferating CD34+CD38+ BM cells. Our results could indicate that these WT1-expressing CD34+ BM cells were normal counterparts of leukaemia cells.

Antigens, CD34↗

GeneExt: a gene model extension tool for enhanced single-cell RNA-seq analysis.

MOTIVATION: Incomplete gene models negatively impact single-cell gene expression quantification. This is particularly true in non-model species where often gene 3' ends are inaccurately annotated, while most scRNA-seq methods only capture the 3' transcript region. This results in many genes being incorrectly quantified or not detected. RESULTS: GeneExt leverages scRNA-seq data to refine gene annotations. We exemplify GeneExt usage and its impact on the gene expression quantification of eight non-model organism single-cell atlases. By extending and homogenizing gene annotations, our tool will help improve biological interpretation and cross-species comparisons of cell type expression atlases. AVAILABILITY: GeneExt is available at https://github.com/sebepedroslab/GeneExt (DOI: https://doi.org/10.5281/zenodo.18712940) under a GNU General Public license, together with test data and usage instructions.

Software↗

Single-cell transcriptome revealed the aberrant keratinocytes activation in antigen presentation in atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD), a common chronic inflammatory skin disease, has been extensively studied using single-cell genomics. However, keratinocytes, as key effector cells in AD, have underlying mechanisms remain incompletely understood and require further investigation. METHODS: We integrated single-cell transcriptomic data from skin tissues of healthy controls, chronic active AD patients, spontaneously healed AD (SHAD) patients, and an ovalbumin-induced AD mouse model. The study particularly emphasized the gene expression and cellular dynamics of keratinocytes across the different groups, as well as their interactions with immune cells. RESULTS: Compared to healthy controls, we observed significant changes in the keratinocyte transcriptome, cellular state, and keratinocyte-immune cell ligand-receptor interactions in AD skin, particularly the marked activation of genes involved in antigen processing and presentation. Interestingly, such gene activation was not observed in keratinocytes from the ovalbumin-induced AD mouse model, despite its phenotype closely resembling human AD. Furthermore, in SHAD, we identified a recovery of both the ligand-receptor interaction patterns and antigen processing and presentation genes, accompanied by a notable shift in the transcriptome. This involved a significant downregulation of genes related to cytoplasmic transcription and oxidative phosphorylation. Notably, this pattern was not observed in the self-healing mouse model following the removal of ovalbumin stimulation. CONCLUSION: Our results suggest that the persistent activation of antigen processing and presentation pathways in keratinocytes may be a key driver of chronic inflammation in AD. Therefore, redirecting anti-allergic therapeutic strategies from solely targeting immune cells to targeting of keratinocyte-mediated antigen presentation may offer a more effective approach. Furthermore, we raise concerns about the use of ovalbumin-induced mouse models to recapitulate human chronic AD, as the underlying mechanisms may differ significantly.

Dermatitis, Atopic↗

SIMS: A deep-learning label transfer tool for single-cell RNA sequencing analysis.

Cell atlases serve as vital references for automating cell labeling in new samples, yet existing classification algorithms struggle with accuracy. Here we introduce SIMS (scalable, interpretable machine learning for single cell), a low-code data-efficient pipeline for single-cell RNA classification. We benchmark SIMS against datasets from different tissues and species. We demonstrate SIMS's efficacy in classifying cells in the brain, achieving high accuracy even with small training sets (<3,500 cells) and across different samples. SIMS accurately predicts neuronal subtypes in the developing brain, shedding light on genetic changes during neuronal differentiation and postmitotic fate refinement. Finally, we apply SIMS to single-cell RNA datasets of cortical organoids to predict cell identities and uncover genetic variations between cell lines. SIMS identifies cell-line differences and misannotated cell lineages in human cortical organoids derived from different pluripotent stem cell lines. Altogether, we show that SIMS is a versatile and robust tool for cell-type classification from single-cell datasets.

Single-Cell Analysis↗

Nanoliter chemistry combined with mass spectrometry for peptide mapping of proteins from single mammalian cell lysates.

A nanoliter-chemistry station combined with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was developed to characterize proteins at the attomole level. Chemical reactions including protein digestion were carried out in nanoliter or subnanoliter volumes, followed by microspot sample deposition of the digest to a MALDI-TOF mass spectrometer. Accurate mass determination of the peptides from the enzyme digest, in conjunction with protein database searching, allowed the identification of the proteins in the protein database. This method is particularly useful for handling small-volume samples such as in single-cell analysis. The high sensitivity and specificity of this method were demonstrated by peptide mapping and identifying hemoglobin variants of sickle cell disease from a single red blood cell. The approach of combining nanoliter chemistry with highly sensitive mass spectrometric analysis should find general use in characterizing proteins from biological systems where only a limited amount of material is available for interrogation.

Animals↗

Texture analysis of cervical cell nuclei by segmentation of chromatin patterns.

Texture parameters of the nuclear chromatin pattern can contribute to the automated classification of specimens on the basis of single cell analysis in cervical cytology. Current texture parameters are abstract and therefore hamper understanding. In this paper texture parameters are described that can be derived from the chromatin pattern after segmentation of the nuclear image. These texture parameters are more directly related to the visual properties of the chromatin pattern. The image segmentation procedure is based on a region grow algorithm which specifically isolates high chromatin density. The texture analysis method has been tested on a data set of images of 112 cervical nuclei on photographic negatives digitized with a step size of 0.125 micron. The preliminary results of a classification trial indicate that these visually interpretable parameters have promising discriminatory power for the distinction between negative and positive specimens.

Carcinoma↗