1
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Carilli M, Gorin G, Choi Y, Chari T, Pachter L. Biophysical modeling with variational autoencoders for bimodal, single-cell RNA sequencing data. Nat Methods 2024; 21:1466-1469. [PMID: 39054391 DOI: 10.1038/s41592-024-02365-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 06/27/2024] [Indexed: 07/27/2024]
Abstract
Here we present biVI, which combines the variational autoencoder framework of scVI with biophysical models describing the transcription and splicing kinetics of RNA molecules. We demonstrate on simulated and experimental single-cell RNA sequencing data that biVI retains the variational autoencoder's ability to capture cell type structure in a low-dimensional space while further enabling genome-wide exploration of the biophysical mechanisms, such as system burst sizes and degradation rates, that underlie observations.
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Affiliation(s)
- Maria Carilli
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Gennady Gorin
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
- Fauna Bio, Emeryville, CA, USA
| | - Yongin Choi
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
- Genome Center, University of California, Davis, Davis, CA, USA
| | - Tara Chari
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
- Department of Computing and Mathematical Sciences, California Institute of Technology, Pasadena, CA, USA.
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2
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Yang X, Mann KK, Wu H, Ding J. scCross: a deep generative model for unifying single-cell multi-omics with seamless integration, cross-modal generation, and in silico exploration. Genome Biol 2024; 25:198. [PMID: 39075536 PMCID: PMC11285326 DOI: 10.1186/s13059-024-03338-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 07/16/2024] [Indexed: 07/31/2024] Open
Abstract
Single-cell multi-omics data reveal complex cellular states, providing significant insights into cellular dynamics and disease. Yet, integration of multi-omics data presents challenges. Some modalities have not reached the robustness or clarity of established transcriptomics. Coupled with data scarcity for less established modalities and integration intricacies, these challenges limit our ability to maximize single-cell omics benefits. We introduce scCross, a tool leveraging variational autoencoders, generative adversarial networks, and the mutual nearest neighbors (MNN) technique for modality alignment. By enabling single-cell cross-modal data generation, multi-omics data simulation, and in silico cellular perturbations, scCross enhances the utility of single-cell multi-omics studies.
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Affiliation(s)
- Xiuhui Yang
- School of Software, Shandong University, 1500 Shunhua, Jinan, 250101, Shandong, China
- Meakins-Christie Laboratories, Department of Medicine, McGill University Health Centre, Montreal, H4A 3J1, QC, Canada
- Quantitative Life Sciences, Faculty of Medicine & Health Sciences, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Koren K Mann
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, H3G 1Y6, Canada
| | - Hao Wu
- School of Software, Shandong University, 1500 Shunhua, Jinan, 250101, Shandong, China.
| | - Jun Ding
- Meakins-Christie Laboratories, Department of Medicine, McGill University Health Centre, Montreal, H4A 3J1, QC, Canada.
- Quantitative Life Sciences, Faculty of Medicine & Health Sciences, McGill University, Montreal, QC, H3G 1Y6, Canada.
- Mila-Quebec AI Institute, Montreal, QC, H2S 3H1, Canada.
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3
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Wang J, Fonseca GJ, Ding J. scSemiProfiler: Advancing large-scale single-cell studies through semi-profiling with deep generative models and active learning. Nat Commun 2024; 15:5989. [PMID: 39013867 PMCID: PMC11252419 DOI: 10.1038/s41467-024-50150-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 06/28/2024] [Indexed: 07/18/2024] Open
Abstract
Single-cell sequencing is a crucial tool for dissecting the cellular intricacies of complex diseases. Its prohibitive cost, however, hampers its application in expansive biomedical studies. Traditional cellular deconvolution approaches can infer cell type proportions from more affordable bulk sequencing data, yet they fall short in providing the detailed resolution required for single-cell-level analyses. To overcome this challenge, we introduce "scSemiProfiler", an innovative computational framework that marries deep generative models with active learning strategies. This method adeptly infers single-cell profiles across large cohorts by fusing bulk sequencing data with targeted single-cell sequencing from a few rigorously chosen representatives. Extensive validation across heterogeneous datasets verifies the precision of our semi-profiling approach, aligning closely with true single-cell profiling data and empowering refined cellular analyses. Originally developed for extensive disease cohorts, "scSemiProfiler" is adaptable for broad applications. It provides a scalable, cost-effective solution for single-cell profiling, facilitating in-depth cellular investigation in various biological domains.
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Affiliation(s)
- Jingtao Wang
- Meakins-Christe Laboratories, Research Institute of McGill University Health Centre, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada
- Department of Medicine, Division of Experimental Medicine, McGill University, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada
| | - Gregory J Fonseca
- Meakins-Christe Laboratories, Research Institute of McGill University Health Centre, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada
- Department of Medicine, Division of Experimental Medicine, McGill University, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada
- Quantitative Life Sciences, McGill University, 845 Rue Sherbrooke Ouest, Montreal, H3A 0G4, Quebec, Canada
| | - Jun Ding
- Meakins-Christe Laboratories, Research Institute of McGill University Health Centre, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada.
- Department of Medicine, Division of Experimental Medicine, McGill University, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada.
- Quantitative Life Sciences, McGill University, 845 Rue Sherbrooke Ouest, Montreal, H3A 0G4, Quebec, Canada.
- School of Computer Science, McGill University, 3480 Rue University, Montreal, H3A 2A7, Quebec, Canada.
- Mila-Quebec AI Institute, 6666 Rue Saint-Urbain, Montreal, H2S 3H1, Quebec, Canada.
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4
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Chari T, Gorin G, Pachter L. Stochastic Modeling of Biophysical Responses to Perturbation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.04.602131. [PMID: 39005347 PMCID: PMC11245117 DOI: 10.1101/2024.07.04.602131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Recent advances in high-throughput, multi-condition experiments allow for genome-wide investigation of how perturbations affect transcription and translation in the cell across multiple biological entities or modalities, from chromatin and mRNA information to protein production and spatial morphology. This presents an unprecedented opportunity to unravel how the processes of DNA and RNA regulation direct cell fate determination and disease response. Most methods designed for analyzing large-scale perturbation data focus on the observational outcomes, e.g., expression; however, many potential transcriptional mechanisms, such as transcriptional bursting or splicing dynamics, can underlie these complex and noisy observations. In this analysis, we demonstrate how a stochastic biophysical modeling approach to interpreting high-throughout perturbation data enables deeper investigation of the 'how' behind such molecular measurements. Our approach takes advantage of modalities already present in data produced with current technologies, such as nascent and mature mRNA measurements, to illuminate transcriptional dynamics induced by perturbation, predict kinetic behaviors in new perturbation settings, and uncover novel populations of cells with distinct kinetic responses to perturbation.
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Affiliation(s)
- Tara Chari
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California
| | | | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California
- Department of Computing and Mathematical Sciences, California Institute of Technology, Pasadena, California
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5
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Yu H, Zheng Y, Yang X. scDM: A deep generative method for cell surface protein prediction with diffusion model. J Mol Biol 2024; 436:168610. [PMID: 38754773 DOI: 10.1016/j.jmb.2024.168610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/18/2024]
Abstract
The executors of organismal functions are proteins, and the transition from RNA to protein is subject to post-transcriptional regulation; therefore, considering both RNA and surface protein expression simultaneously can provide additional evidence of biological processes. Cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq) technology can measure both RNA and protein expression in single cells, but these experiments are expensive and time-consuming. Due to the lack of computational tools for predicting surface proteins, we used datasets obtained with CITE-seq technology to design a deep generative prediction method based on diffusion models and to find biological discoveries through the prediction results. In our method, the scDM, which predicts protein expression values from RNA expression values of individual cells, uses a novel way of encoding the data into a model and generates predicted samples by introducing Gaussian noise to gradually remove the noise to learn the data distribution during the modelling process. Comprehensive evaluation across different datasets demonstrated that our predictions yielded satisfactory results and further demonstrated the effectiveness of incorporating information from single-cell multiomics data into diffusion models for biological studies. We also found that new directions for discovering therapeutic drug targets could be provided by jointly analysing the predictive value of surface protein expression and cancer cell drug scores.
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Affiliation(s)
- Hanlei Yu
- School of Information Science and Engineering, Shandong Normal University, Jinan 250358, China
| | - Yuanjie Zheng
- School of Information Science and Engineering, Shandong Normal University, Jinan 250358, China.
| | - Xinbo Yang
- School of Information Science and Engineering, Shandong Normal University, Jinan 250358, China
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6
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Jilani M, Degras D, Haspel N. Elucidating Cancer Subtypes by Using the Relationship between DNA Methylation and Gene Expression. Genes (Basel) 2024; 15:631. [PMID: 38790260 PMCID: PMC11121157 DOI: 10.3390/genes15050631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Advancements in the field of next generation sequencing (NGS) have generated vast amounts of data for the same set of subjects. The challenge that arises is how to combine and reconcile results from different omics studies, such as epigenome and transcriptome, to improve the classification of disease subtypes. In this study, we introduce sCClust (sparse canonical correlation analysis with clustering), a technique to combine high-dimensional omics data using sparse canonical correlation analysis (sCCA), such that the correlation between datasets is maximized. This stage is followed by clustering the integrated data in a lower-dimensional space. We apply sCClust to gene expression and DNA methylation data for three cancer genomics datasets from the Cancer Genome Atlas (TCGA) to distinguish between underlying subtypes. We evaluate the identified subtypes using Kaplan-Meier plots and hazard ratio analysis on the three types of cancer-GBM (glioblastoma multiform), lung cancer and colon cancer. Comparison with subtypes identified by both single- and multi-omics studies implies improved clinical association. We also perform pathway over-representation analysis in order to identify up-regulated and down-regulated genes as tentative drug targets. The main goal of the paper is twofold: the integration of epigenomic and transcriptomic datasets followed by elucidating subtypes in the latent space. The significance of this study lies in the enhanced categorization of cancer data, which is crucial to precision medicine.
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Affiliation(s)
- Muneeba Jilani
- Department of Computer Science, University of Massachusetts Boston, Boston, MA 02125, USA;
| | - David Degras
- Department of Mathematics, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Nurit Haspel
- Department of Computer Science, University of Massachusetts Boston, Boston, MA 02125, USA;
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7
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Qiu Y, Yang L, Jiang H, Zou Q. scTPC: a novel semisupervised deep clustering model for scRNA-seq data. BIOINFORMATICS (OXFORD, ENGLAND) 2024; 40:btae293. [PMID: 38684178 DOI: 10.1093/bioinformatics/btae293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 04/14/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
MOTIVATION Continuous advancements in single-cell RNA sequencing (scRNA-seq) technology have enabled researchers to further explore the study of cell heterogeneity, trajectory inference, identification of rare cell types, and neurology. Accurate scRNA-seq data clustering is crucial in single-cell sequencing data analysis. However, the high dimensionality, sparsity, and presence of "false" zero values in the data can pose challenges to clustering. Furthermore, current unsupervised clustering algorithms have not effectively leveraged prior biological knowledge, making cell clustering even more challenging. RESULTS This study investigates a semisupervised clustering model called scTPC, which integrates the triplet constraint, pairwise constraint, and cross-entropy constraint based on deep learning. Specifically, the model begins by pretraining a denoising autoencoder based on a zero-inflated negative binomial distribution. Deep clustering is then performed in the learned latent feature space using triplet constraints and pairwise constraints generated from partial labeled cells. Finally, to address imbalanced cell-type datasets, a weighted cross-entropy loss is introduced to optimize the model. A series of experimental results on 10 real scRNA-seq datasets and five simulated datasets demonstrate that scTPC achieves accurate clustering with a well-designed framework. AVAILABILITY AND IMPLEMENTATION scTPC is a Python-based algorithm, and the code is available from https://github.com/LF-Yang/Code or https://zenodo.org/records/10951780.
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Affiliation(s)
- Yushan Qiu
- School of Mathematical Sciences, Shenzhen University, Shenzhen, Guangdong 518000, China
| | - Lingfei Yang
- School of Mathematical Sciences, Shenzhen University, Shenzhen, Guangdong 518000, China
| | - Hao Jiang
- School of Mathematics, Renmin University of China, Haidian District, Beijing 100872, China
| | - Quan Zou
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610056, China
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8
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Wang H, Liu Z, Ma X. Learning Consistency and Specificity of Cells From Single-Cell Multi-Omic Data. IEEE J Biomed Health Inform 2024; 28:3134-3145. [PMID: 38709615 DOI: 10.1109/jbhi.2024.3370868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Advancements in single-cell technologies concomitantly develop the epigenomic and transcriptomic profiles at the cell levels, providing opportunities to explore the potential biological mechanisms. Even though significant efforts have been dedicated to them, it remains challenging for the integration analysis of multi-omic data of single-cell because of the heterogeneity, complicated coupling and interpretability of data. To handle these issues, we propose a novel self-representation Learning-based Multi-omics data Integrative Clustering algorithm (sLMIC) for the integration of single-cell epigenomic profiles (DNA methylation or scATAC-seq) and transcriptomic (scRNA-seq), which the consistent and specific features of cells are explicitly extracted facilitating the cell clustering. Specifically, sLMIC constructs a graph for each type of single-cell data, thereby transforming omics data into multi-layer networks, which effectively removes heterogeneity of omic data. Then, sLMIC employs the low-rank and exclusivity constraints to separate the self-representation of cells into two parts, i.e., the shared and specific features, which explicitly characterize the consistency and diversity of omic data, providing an effective strategy to model the structure of cell types. Feature extraction and cell clustering are jointly formulated as an overall objective function, where latent features of data are obtained under the guidance of cell clustering. The extensive experimental results on 13 multi-omics datasets of single-cell from diverse organisms and tissues indicate that sLMIC observably exceeds the advanced algorithms regarding various measurements.
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9
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Qiu Y, Guo D, Zhao P, Zou Q. scMNMF: a novel method for single-cell multi-omics clustering based on matrix factorization. Brief Bioinform 2024; 25:bbae228. [PMID: 38754408 PMCID: PMC11097994 DOI: 10.1093/bib/bbae228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/02/2024] [Accepted: 04/22/2024] [Indexed: 05/18/2024] Open
Abstract
MOTIVATION The technology for analyzing single-cell multi-omics data has advanced rapidly and has provided comprehensive and accurate cellular information by exploring cell heterogeneity in genomics, transcriptomics, epigenomics, metabolomics and proteomics data. However, because of the high-dimensional and sparse characteristics of single-cell multi-omics data, as well as the limitations of various analysis algorithms, the clustering performance is generally poor. Matrix factorization is an unsupervised, dimensionality reduction-based method that can cluster individuals and discover related omics variables from different blocks. Here, we present a novel algorithm that performs joint dimensionality reduction learning and cell clustering analysis on single-cell multi-omics data using non-negative matrix factorization that we named scMNMF. We formulate the objective function of joint learning as a constrained optimization problem and derive the corresponding iterative formulas through alternating iterative algorithms. The major advantage of the scMNMF algorithm remains its capability to explore hidden related features among omics data. Additionally, the feature selection for dimensionality reduction and cell clustering mutually influence each other iteratively, leading to a more effective discovery of cell types. We validated the performance of the scMNMF algorithm using two simulated and five real datasets. The results show that scMNMF outperformed seven other state-of-the-art algorithms in various measurements. AVAILABILITY AND IMPLEMENTATION scMNMF code can be found at https://github.com/yushanqiu/scMNMF.
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Affiliation(s)
- Yushan Qiu
- School of Mathematical Sciences, Shenzhen University, 518000, Guangdong, China
| | - Dong Guo
- School of Mathematical Sciences, Shenzhen University, 518000, Guangdong, China
| | - Pu Zhao
- College of Life and Health Sciences, Northeastern University, Shenyang, 110169, China
| | - Quan Zou
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610056, China
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10
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Yao X, Jiang X, Luo H, Liang H, Ye X, Wei Y, Cong S. MOCAT: multi-omics integration with auxiliary classifiers enhanced autoencoder. BioData Min 2024; 17:9. [PMID: 38444019 PMCID: PMC10916109 DOI: 10.1186/s13040-024-00360-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/29/2024] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND Integrating multi-omics data is emerging as a critical approach in enhancing our understanding of complex diseases. Innovative computational methods capable of managing high-dimensional and heterogeneous datasets are required to unlock the full potential of such rich and diverse data. METHODS We propose a Multi-Omics integration framework with auxiliary Classifiers-enhanced AuToencoders (MOCAT) to utilize intra- and inter-omics information comprehensively. Additionally, attention mechanisms with confidence learning are incorporated for enhanced feature representation and trustworthy prediction. RESULTS Extensive experiments were conducted on four benchmark datasets to evaluate the effectiveness of our proposed model, including BRCA, ROSMAP, LGG, and KIPAN. Our model significantly improved most evaluation measurements and consistently surpassed the state-of-the-art methods. Ablation studies showed that the auxiliary classifiers significantly boosted classification accuracy in the ROSMAP and LGG datasets. Moreover, the attention mechanisms and confidence evaluation block contributed to improvements in the predictive accuracy and generalizability of our model. CONCLUSIONS The proposed framework exhibits superior performance in disease classification and biomarker discovery, establishing itself as a robust and versatile tool for analyzing multi-layer biological data. This study highlights the significance of elaborated designed deep learning methodologies in dissecting complex disease phenotypes and improving the accuracy of disease predictions.
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Affiliation(s)
- Xiaohui Yao
- Qingdao Innovation and Development Center, Harbin Engineering University, 1777 Sansha Rd, Qingdao, 266000, Shandong, China
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China
| | - Xiaohan Jiang
- Qingdao Innovation and Development Center, Harbin Engineering University, 1777 Sansha Rd, Qingdao, 266000, Shandong, China
| | - Haoran Luo
- Qingdao Innovation and Development Center, Harbin Engineering University, 1777 Sansha Rd, Qingdao, 266000, Shandong, China
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China
| | - Hong Liang
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China
| | - Xiufen Ye
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China
| | - Yanhui Wei
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China
| | - Shan Cong
- Qingdao Innovation and Development Center, Harbin Engineering University, 1777 Sansha Rd, Qingdao, 266000, Shandong, China.
- College of Intelligent Systems Science and Engineering, Harbin Engineering University, 145 Nantong St, Harbin, 150001, Heilongjiang, China.
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11
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Choi JM, Park C, Chae H. moSCminer: a cell subtype classification framework based on the attention neural network integrating the single-cell multi-omics dataset on the cloud. PeerJ 2024; 12:e17006. [PMID: 38426141 PMCID: PMC10903350 DOI: 10.7717/peerj.17006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/05/2024] [Indexed: 03/02/2024] Open
Abstract
Single-cell omics sequencing has rapidly advanced, enabling the quantification of diverse omics profiles at a single-cell resolution. To facilitate comprehensive biological insights, such as cellular differentiation trajectories, precise annotation of cell subtypes is essential. Conventional methods involve clustering cells and manually assigning subtypes based on canonical markers, a labor-intensive and expert-dependent process. Hence, an automated computational prediction framework is crucial. While several classification frameworks for predicting cell subtypes from single-cell RNA sequencing datasets exist, these methods solely rely on single-omics data, offering insights at a single molecular level. They often miss inter-omic correlations and a holistic understanding of cellular processes. To address this, the integration of multi-omics datasets from individual cells is essential for accurate subtype annotation. This article introduces moSCminer, a novel framework for classifying cell subtypes that harnesses the power of single-cell multi-omics sequencing datasets through an attention-based neural network operating at the omics level. By integrating three distinct omics datasets-gene expression, DNA methylation, and DNA accessibility-while accounting for their biological relationships, moSCminer excels at learning the relative significance of each omics feature. It then transforms this knowledge into a novel representation for cell subtype classification. Comparative evaluations against standard machine learning-based classifiers demonstrate moSCminer's superior performance, consistently achieving the highest average performance on real datasets. The efficacy of multi-omics integration is further corroborated through an in-depth analysis of the omics-level attention module, which identifies potential markers for cell subtype annotation. To enhance accessibility and scalability, moSCminer is accessible as a user-friendly web-based platform seamlessly connected to a cloud system, publicly accessible at http://203.252.206.118:5568. Notably, this study marks the pioneering integration of three single-cell multi-omics datasets for cell subtype identification.
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Affiliation(s)
- Joung Min Choi
- Department of Computer Science, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, Virginia, United States
| | - Chaelin Park
- Division of Computer Science, Sookmyung Women’s University, Seoul, South Korea
| | - Heejoon Chae
- Division of Computer Science, Sookmyung Women’s University, Seoul, South Korea
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12
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He Z, Hu S, Chen Y, An S, Zhou J, Liu R, Shi J, Wang J, Dong G, Shi J, Zhao J, Ou-Yang L, Zhu Y, Bo X, Ying X. Mosaic integration and knowledge transfer of single-cell multimodal data with MIDAS. Nat Biotechnol 2024:10.1038/s41587-023-02040-y. [PMID: 38263515 DOI: 10.1038/s41587-023-02040-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 10/23/2023] [Indexed: 01/25/2024]
Abstract
Integrating single-cell datasets produced by multiple omics technologies is essential for defining cellular heterogeneity. Mosaic integration, in which different datasets share only some of the measured modalities, poses major challenges, particularly regarding modality alignment and batch effect removal. Here, we present a deep probabilistic framework for the mosaic integration and knowledge transfer (MIDAS) of single-cell multimodal data. MIDAS simultaneously achieves dimensionality reduction, imputation and batch correction of mosaic data by using self-supervised modality alignment and information-theoretic latent disentanglement. We demonstrate its superiority to 19 other methods and reliability by evaluating its performance in trimodal and mosaic integration tasks. We also constructed a single-cell trimodal atlas of human peripheral blood mononuclear cells and tailored transfer learning and reciprocal reference mapping schemes to enable flexible and accurate knowledge transfer from the atlas to new data. Applications in mosaic integration, pseudotime analysis and cross-tissue knowledge transfer on bone marrow mosaic datasets demonstrate the versatility and superiority of MIDAS. MIDAS is available at https://github.com/labomics/midas .
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Affiliation(s)
- Zhen He
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Shuofeng Hu
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yaowen Chen
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Sijing An
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Jiahao Zhou
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
- College of Electronics and Information Engineering, Shenzhen University, Shenzhen, China
| | - Runyan Liu
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Junfeng Shi
- School of Automation, China University of Geosciences, Wuhan, China
| | - Jing Wang
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Guohua Dong
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Jinhui Shi
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Jiaxin Zhao
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Le Ou-Yang
- College of Electronics and Information Engineering, Shenzhen University, Shenzhen, China
| | - Yuan Zhu
- School of Automation, China University of Geosciences, Wuhan, China
| | - Xiaochen Bo
- Institute of Health Service and Transfusion Medicine, Beijing, China.
| | - Xiaomin Ying
- Center for Computational Biology, Beijing Institute of Basic Medical Sciences, Beijing, China.
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13
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Hu D, Liang K, Dong Z, Wang J, Zhao Y, He K. Effective multi-modal clustering method via skip aggregation network for parallel scRNA-seq and scATAC-seq data. Brief Bioinform 2024; 25:bbae102. [PMID: 38493338 PMCID: PMC10944573 DOI: 10.1093/bib/bbae102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/06/2024] [Accepted: 02/16/2024] [Indexed: 03/18/2024] Open
Abstract
In recent years, there has been a growing trend in the realm of parallel clustering analysis for single-cell RNA-seq (scRNA) and single-cell Assay of Transposase Accessible Chromatin (scATAC) data. However, prevailing methods often treat these two data modalities as equals, neglecting the fact that the scRNA mode holds significantly richer information compared to the scATAC. This disregard hinders the model benefits from the insights derived from multiple modalities, compromising the overall clustering performance. To this end, we propose an effective multi-modal clustering model scEMC for parallel scRNA and Assay of Transposase Accessible Chromatin data. Concretely, we have devised a skip aggregation network to simultaneously learn global structural information among cells and integrate data from diverse modalities. To safeguard the quality of integrated cell representation against the influence stemming from sparse scATAC data, we connect the scRNA data with the aggregated representation via skip connection. Moreover, to effectively fit the real distribution of cells, we introduced a Zero Inflated Negative Binomial-based denoising autoencoder that accommodates corrupted data containing synthetic noise, concurrently integrating a joint optimization module that employs multiple losses. Extensive experiments serve to underscore the effectiveness of our model. This work contributes significantly to the ongoing exploration of cell subpopulations and tumor microenvironments, and the code of our work will be public at https://github.com/DayuHuu/scEMC.
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Affiliation(s)
- Dayu Hu
- School of Computer, National University of Defense Technology, No. 109 Deya Road, 410073 Changsha, Hunan, China
| | - Ke Liang
- School of Computer, National University of Defense Technology, No. 109 Deya Road, 410073 Changsha, Hunan, China
| | - Zhibin Dong
- School of Computer, National University of Defense Technology, No. 109 Deya Road, 410073 Changsha, Hunan, China
| | - Jun Wang
- School of Computer, National University of Defense Technology, No. 109 Deya Road, 410073 Changsha, Hunan, China
| | - Yawei Zhao
- Medical Big Data Research Center, Chinese PLA General Hospital, No. 28 Fuxing Road, 100853 Beijing, China
| | - Kunlun He
- Medical Big Data Research Center, Chinese PLA General Hospital, No. 28 Fuxing Road, 100853 Beijing, China
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14
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Tang W, Wen H, Liu R, Ding J, Jin W, Xie Y, Liu H, Tang J. Single-Cell Multimodal Prediction via Transformers. ARXIV 2023:arXiv:2303.00233v3. [PMID: 37645040 PMCID: PMC10462176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The recent development of multimodal single-cell technology has made the possibility of acquiring multiple omics data from individual cells, thereby enabling a deeper understanding of cellular states and dynamics. Nevertheless, the proliferation of multimodal single-cell data also introduces tremendous challenges in modeling the complex interactions among different modalities. The recently advanced methods focus on constructing static interaction graphs and applying graph neural networks (GNNs) to learn from multimodal data. However, such static graphs can be suboptimal as they do not take advantage of the downstream task information; meanwhile GNNs also have some inherent limitations when deeply stacking GNN layers. To tackle these issues, in this work, we investigate how to leverage transformers for multimodal single-cell data in an end-to-end manner while exploiting downstream task information. In particular, we propose a scMoFormer framework which can readily incorporate external domain knowledge and model the interactions within each modality and cross modalities. Extensive experiments demonstrate that scMoFormer achieves superior performance on various benchmark datasets. Remarkably, scMoFormer won a Kaggle silver medal with the rank of 24/1221 (Top 2%) without ensemble in a NeurIPS 2022 competition. Our implementation is publicly available at Github.
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15
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Li W, Xiang B, Yang F, Rong Y, Yin Y, Yao J, Zhang H. scMHNN: a novel hypergraph neural network for integrative analysis of single-cell epigenomic, transcriptomic and proteomic data. Brief Bioinform 2023; 24:bbad391. [PMID: 37930028 DOI: 10.1093/bib/bbad391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/09/2023] [Accepted: 10/11/2023] [Indexed: 11/07/2023] Open
Abstract
Technological advances have now made it possible to simultaneously profile the changes of epigenomic, transcriptomic and proteomic at the single cell level, allowing a more unified view of cellular phenotypes and heterogeneities. However, current computational tools for single-cell multi-omics data integration are mainly tailored for bi-modality data, so new tools are urgently needed to integrate tri-modality data with complex associations. To this end, we develop scMHNN to integrate single-cell multi-omics data based on hypergraph neural network. After modeling the complex data associations among various modalities, scMHNN performs message passing process on the multi-omics hypergraph, which can capture the high-order data relationships and integrate the multiple heterogeneous features. Followingly, scMHNN learns discriminative cell representation via a dual-contrastive loss in self-supervised manner. Based on the pretrained hypergraph encoder, we further introduce the pre-training and fine-tuning paradigm, which allows more accurate cell-type annotation with only a small number of labeled cells as reference. Benchmarking results on real and simulated single-cell tri-modality datasets indicate that scMHNN outperforms other competing methods on both cell clustering and cell-type annotation tasks. In addition, we also demonstrate scMHNN facilitates various downstream tasks, such as cell marker detection and enrichment analysis.
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Affiliation(s)
- Wei Li
- College of Artificial Intelligence, Nankai University, Tongyan Road, 300350 Tianjin, China
- AI Lab, Tencent, Gaoxin 9th South Road, 518000 Shenzhen, China
| | - Bin Xiang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Yueyang Road, 200031 Shanghai, China
| | - Fan Yang
- AI Lab, Tencent, Gaoxin 9th South Road, 518000 Shenzhen, China
| | - Yu Rong
- AI Lab, Tencent, Gaoxin 9th South Road, 518000 Shenzhen, China
| | - Yanbin Yin
- Department of Food Science and Technology, University of Nebraska - Lincoln, 1400 R Street, 68588 Nebraska, USA
| | - Jianhua Yao
- AI Lab, Tencent, Gaoxin 9th South Road, 518000 Shenzhen, China
| | - Han Zhang
- College of Artificial Intelligence, Nankai University, Tongyan Road, 300350 Tianjin, China
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16
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Athaya T, Ripan RC, Li X, Hu H. Multimodal deep learning approaches for single-cell multi-omics data integration. Brief Bioinform 2023; 24:bbad313. [PMID: 37651607 PMCID: PMC10516349 DOI: 10.1093/bib/bbad313] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/23/2023] [Accepted: 07/18/2023] [Indexed: 09/02/2023] Open
Abstract
Integrating single-cell multi-omics data is a challenging task that has led to new insights into complex cellular systems. Various computational methods have been proposed to effectively integrate these rapidly accumulating datasets, including deep learning. However, despite the proven success of deep learning in integrating multi-omics data and its better performance over classical computational methods, there has been no systematic study of its application to single-cell multi-omics data integration. To fill this gap, we conducted a literature review to explore the use of multimodal deep learning techniques in single-cell multi-omics data integration, taking into account recent studies from multiple perspectives. Specifically, we first summarized different modalities found in single-cell multi-omics data. We then reviewed current deep learning techniques for processing multimodal data and categorized deep learning-based integration methods for single-cell multi-omics data according to data modality, deep learning architecture, fusion strategy, key tasks and downstream analysis. Finally, we provided insights into using these deep learning models to integrate multi-omics data and better understand single-cell biological mechanisms.
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Affiliation(s)
- Tasbiraha Athaya
- Department of Computer Science, University of Central Florida, Orlando, Florida, United States of America
| | - Rony Chowdhury Ripan
- Department of Computer Science, University of Central Florida, Orlando, Florida, United States of America
| | - Xiaoman Li
- Burnett School of Biomedical Science, College of Medicine, University of Central Florida, Orlando, Florida, United States of America
| | - Haiyan Hu
- Department of Computer Science, University of Central Florida, Orlando, Florida, United States of America
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17
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Chari T, Gorin G, Pachter L. Biophysically Interpretable Inference of Cell Types from Multimodal Sequencing Data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.17.558131. [PMID: 37745403 PMCID: PMC10516047 DOI: 10.1101/2023.09.17.558131] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Multimodal, single-cell genomics technologies enable simultaneous capture of multiple facets of DNA and RNA processing in the cell. This creates opportunities for transcriptome-wide, mechanistic studies of cellular processing in heterogeneous cell types, with applications ranging from inferring kinetic differences between cells, to the role of stochasticity in driving heterogeneity. However, current methods for determining cell types or 'clusters' present in multimodal data often rely on ad hoc or independent treatment of modalities, and assumptions ignoring inherent properties of the count data. To enable interpretable and consistent cell cluster determination from multimodal data, we present meK-Means (mechanistic K-Means) which integrates modalities and learns underlying, shared biophysical states through a unifying model of transcription. In particular, we demonstrate how meK-Means can be used to cluster cells from unspliced and spliced mRNA count modalities. By utilizing the causal, physical relationships underlying these modalities, we identify shared transcriptional kinetics across cells, which induce the observed gene expression profiles, and provide an alternative definition for 'clusters' through the governing parameters of cellular processes.
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Affiliation(s)
- Tara Chari
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California
| | - Gennady Gorin
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California
| | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California
- Department of Computing and Mathematical Sciences, California Institute of Technology, Pasadena, California
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18
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Yu L, Liu C, Yang JYH, Yang P. Ensemble deep learning of embeddings for clustering multimodal single-cell omics data. Bioinformatics 2023; 39:btad382. [PMID: 37314966 PMCID: PMC10287920 DOI: 10.1093/bioinformatics/btad382] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/16/2023] [Accepted: 06/12/2023] [Indexed: 06/16/2023] Open
Abstract
MOTIVATION Recent advances in multimodal single-cell omics technologies enable multiple modalities of molecular attributes, such as gene expression, chromatin accessibility, and protein abundance, to be profiled simultaneously at a global level in individual cells. While the increasing availability of multiple data modalities is expected to provide a more accurate clustering and characterization of cells, the development of computational methods that are capable of extracting information embedded across data modalities is still in its infancy. RESULTS We propose SnapCCESS for clustering cells by integrating data modalities in multimodal single-cell omics data using an unsupervised ensemble deep learning framework. By creating snapshots of embeddings of multimodality using variational autoencoders, SnapCCESS can be coupled with various clustering algorithms for generating consensus clustering of cells. We applied SnapCCESS with several clustering algorithms to various datasets generated from popular multimodal single-cell omics technologies. Our results demonstrate that SnapCCESS is effective and more efficient than conventional ensemble deep learning-based clustering methods and outperforms other state-of-the-art multimodal embedding generation methods in integrating data modalities for clustering cells. The improved clustering of cells from SnapCCESS will pave the way for more accurate characterization of cell identity and types, an essential step for various downstream analyses of multimodal single-cell omics data. AVAILABILITY AND IMPLEMENTATION SnapCCESS is implemented as a Python package and is freely available from https://github.com/PYangLab/SnapCCESS under the open-source license of GPL-3. The data used in this study are publicly available (see section 'Data availability').
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Affiliation(s)
- Lijia Yu
- Computational Systems Biology Group, Children’s Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
- School of Mathematics and Statistics, Faculty of Science, University of Sydney, NSW 2006, Australia
- Sydney Precision Data Science Centre, University of Sydney, NSW 2006, Australia
| | - Chunlei Liu
- Computational Systems Biology Group, Children’s Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
- Sydney Precision Data Science Centre, University of Sydney, NSW 2006, Australia
| | - Jean Yee Hwa Yang
- School of Mathematics and Statistics, Faculty of Science, University of Sydney, NSW 2006, Australia
- Sydney Precision Data Science Centre, University of Sydney, NSW 2006, Australia
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia
- Laboratory of Data Discovery for Health Limited (D4H), Hong Kong Science Park, Hong Kong SAR, China
| | - Pengyi Yang
- Computational Systems Biology Group, Children’s Medical Research Institute, Faculty of Medicine and Health, The University of Sydney, Westmead, NSW 2145, Australia
- School of Mathematics and Statistics, Faculty of Science, University of Sydney, NSW 2006, Australia
- Sydney Precision Data Science Centre, University of Sydney, NSW 2006, Australia
- Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia
- Laboratory of Data Discovery for Health Limited (D4H), Hong Kong Science Park, Hong Kong SAR, China
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19
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Carilli M, Gorin G, Choi Y, Chari T, Pachter L. Biophysical modeling with variational autoencoders for bimodal, single-cell RNA sequencing data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.13.523995. [PMID: 36712140 PMCID: PMC9882246 DOI: 10.1101/2023.01.13.523995] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We motivate and present biVI, which combines the variational autoencoder framework of scVI with biophysically motivated, bivariate models for nascent and mature RNA distributions. While previous approaches to integrate bimodal data via the variational autoencoder framework ignore the causal relationship between measurements, biVI models the biophysical processes that give rise to observations. We demonstrate through simulated benchmarking that biVI captures cell type structure in a low-dimensional space and accurately recapitulates parameter values and copy number distributions. On biological data, biVI provides a scalable route for identifying the biophysical mechanisms underlying gene expression. This analytical approach outlines a generalizable strategy for treating multimodal datasets generated by high-throughput, single-cell genomic assays.
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Affiliation(s)
- Maria Carilli
- Division of Biology and Biological Engineering, California Institute of Technology
| | - Gennady Gorin
- Division of Chemistry and Chemical Engineering, California Institute of Technology
| | - Yongin Choi
- Biomedical Engineering Graduate Group, University of California, Davis
- Genome Center, University of California, Davis
| | - Tara Chari
- Division of Biology and Biological Engineering, California Institute of Technology
| | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology
- Department of Computing and Mathematical Sciences, California Institute of Technology
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20
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Wu Z, Lohmöller J, Kuhl C, Wehrle K, Jankowski J. Use of Computation Ecosystems to Analyze the Kidney-Heart Crosstalk. Circ Res 2023; 132:1084-1100. [PMID: 37053282 DOI: 10.1161/circresaha.123.321765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
The identification of mediators for physiologic processes, correlation of molecular processes, or even pathophysiological processes within a single organ such as the kidney or heart has been extensively studied to answer specific research questions using organ-centered approaches in the past 50 years. However, it has become evident that these approaches do not adequately complement each other and display a distorted single-disease progression, lacking holistic multilevel/multidimensional correlations. Holistic approaches have become increasingly significant in understanding and uncovering high dimensional interactions and molecular overlaps between different organ systems in the pathophysiology of multimorbid and systemic diseases like cardiorenal syndrome because of pathological heart-kidney crosstalk. Holistic approaches to unraveling multimorbid diseases are based on the integration, merging, and correlation of extensive, heterogeneous, and multidimensional data from different data sources, both -omics and nonomics databases. These approaches aimed at generating viable and translatable disease models using mathematical, statistical, and computational tools, thereby creating first computational ecosystems. As part of these computational ecosystems, systems medicine solutions focus on the analysis of -omics data in single-organ diseases. However, the data-scientific requirements to address the complexity of multimodality and multimorbidity reach far beyond what is currently available and require multiphased and cross-sectional approaches. These approaches break down complexity into small and comprehensible challenges. Such holistic computational ecosystems encompass data, methods, processes, and interdisciplinary knowledge to manage the complexity of multiorgan crosstalk. Therefore, this review summarizes the current knowledge of kidney-heart crosstalk, along with methods and opportunities that arise from the novel application of computational ecosystems providing a holistic analysis on the example of kidney-heart crosstalk.
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Affiliation(s)
- Zhuojun Wu
- Institute of Molecular Cardiovascular Research (Z.W., J.J.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
- Department of Radiology (C.K.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
| | - Johannes Lohmöller
- Medical Faculty, and Department of Computer Science, Communication and Distributed Systems (COMSYS) (J.L., K.W.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
| | - Christiane Kuhl
- Department of Radiology (C.K.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
| | - Klaus Wehrle
- Institute of Molecular Cardiovascular Research (Z.W., J.J.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
- Medical Faculty, and Department of Computer Science, Communication and Distributed Systems (COMSYS) (J.L., K.W.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
| | - Joachim Jankowski
- Institute of Molecular Cardiovascular Research (Z.W., J.J.), Rheinisch-Westfälische Technische Hochschule Aachen University, Germany
- Department of Pathology, Cardiovascular Research Institute Maastricht (CARIM), University of Maastricht, The Netherlands (J.J.)
- Aachen-Maastricht Institute for Cardiorenal Disease (AMICARE), University Hospital Rheinisch-Westfälische Technische Hochschule Aachen, Germany (J.J.)
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