This record includes training materials associated with the Australian BioCommons workshop 'Single cell RNAseq analysis in R'. This workshop took place over two, 3.5 hour sessions on 26 and 27 October 2023. Event description Analysis and interpretation of single cell RNAseq (scRNAseq) data requires dedicated workflows. In this hands-on workshop we will show you how to perform single cell analysis using Seurat - an R package for QC, analysis, and exploration of single-cell RNAseq data. We will discuss the 'why' behind each step and cover reading in the count data, quality control, filtering, normalisation, clustering, UMAP layout and identification of cluster markers. We will also explore various ways of visualising single cell expression data. This workshop is presented by the Australian BioCommons, Queensland Cyber Infrastructure Foundation (QCIF) and the Monash Genomics and Bioinformatics Platform with the assistance of a network of facilitators from the national Bioinformatics Training Cooperative. Lead trainers: Sarah Williams, Adele Barugahare, Paul Harrison, Laura Perlaza Jimenez Facilitators: Nick Matigan, Valentine Murigneux, Magdalena (Magda) Antczak Infrastructure provision: Uwe Winter Coordinator: Melissa Burke Training materials Materials are shared under a Creative Commons Attribution 4.0 International agreement unless otherwise specified and were current at the time of the event. Files and materials included in this record: Event metadata (PDF): Information about the event including, description, event URL, learning objectives, prerequisites, technical requirements etc. Index of training materials (PDF): List and description of all materials associated with this event including the name, format, location and a brief description of each file. scRNAseq_Schedule (PDF): A breakdown of the topics and timings for the workshop Materials shared elsewhere: This workshop follows the tutorial 'scRNAseq Analysis in R with Seurat' https://swbioinf.github.io/scRNAseqInR_Doco/index.html Slides used to introduce key topics are available via GitHub https://github.com/swbioinf/scRNAseqInR_Doco/tree/main/slides This material is based on the introductory Guided Clustering Tutorial tutorial from Seurat. It is also drawing from a similar workshop held by Monash Bioinformatics Platform Single-Cell-Workshop, with material here.

Summary: Dendritic cells (DCs) orchestrate innate and adaptive immunity, by translating the sensing of distinct danger signals into the induction of different effector lymphocyte responses, to induce different defense mechanisms suited to face distinct types of threats. Hence, DCs are very plastic, which results from two key characteristics. First, DCs encompass distinct cell types specialized in different functions. Second, each DC type can undergo different activation states, fine-tuning its functions depending on its tissue microenvironment and the pathophysiological context, by adapting the output signals it delivers to the input signals it receives. Hence, to better understand DC biology and harness it in the clinic, we must determine which combinations of DC types and activation states mediate which functions, and how.
To decipher the nature, functions and regulation of DC types and their physiological activation states, one of the methods that can be harnessed most successfully is ex vivo single cell RNA sequencing (scRNAseq). However, for new users of this approach, determining which analytics strategy and computational tools to choose can be quite challenging, considering the rapid evolution and broad burgeoning of the field. In addition, awareness must be raised on the need for specific, robust and tractable strategies to annotate cells for cell type identity and activation states. It is also important to emphasize the necessity of examining whether similar cell activation trajectories are inferred by using different, complementary methods. In this chapter, we take these issues into account for providing a pipeline for scRNAseq analysis and illustrating it with a tutorial reanalyzing a public dataset of mononuclear phagocytes isolated from the lungs of naïve or tumor-bearing mice. We describe this pipeline step-by-step, including data quality controls, dimensionality reduction, cell clustering, cell cluster annotation, inference of the cell activation trajectories and investigation of the underpinning molecular regulation. It is accompanied with a more complete tutorial on Github. We anticipate that this method will be helpful for both wet lab and bioinformatics researchers interested in harnessing scRNAseq data for deciphering the biology of DCs or other cell types, and that it will contribute to establishing high standards in the field.

Data:

1. negative_cDC1_relative_signatures.csv : Negative signatures for performing Connectivity Map (cMAP) Analysis

2. positive_cDC1_relative_signatures.csv : Positive signatures for performing Connectivity Map (cMAP) Analysis

ObjectiveTo guide animal experiments, we investigated the similarities and differences between humans and mice in aging and Alzheimer’s disease (AD) at the single-nucleus RNA sequencing (snRNA-seq) or single-cell RNA sequencing (scRNA-seq) level.MethodsMicroglia cells were extracted from dataset GSE198323 of human post-mortem hippocampus. The distributions and proportions of microglia subpopulation cell numbers related to AD or age were compared. This comparison was done between GSE198323 for humans and GSE127892 for mice, respectively. The Seurat R package and harmony R package were used for data analysis and batch effect correction. Differentially expressed genes (DEGs) were identified by FindMarkers function with MAST test. Comparative analyses were conducted on shared genes in DEGs associated with age and AD. The analyses were done between human and mouse using various bioinformatics techniques. The analysis of genes in DEGs related to age was conducted. Similarly, the analysis of genes in DEGs related to AD was performed. Cross-species analyses were conducted using orthologous genes. Comparative analyses of pseudotime between humans and mice were performed using Monocle2.Results(1) Similarities: The proportion of microglial subpopulation Cell_APOE/Apoe shows consistent trends, whether in AD or normal control (NC) groups in both humans and mice. The proportion of Cell_CX3CR1/Cx3cr1, representing homeostatic microglia, remains stable with age in NC groups across species. Tuberculosis and Fc gamma R-mediated phagocytosis pathways are shared in microglia responses to age and AD across species, respectively. (2) Differences: IL1RAPL1 and SPP1 as marker genes are more identifiable in human microglia compared to their mouse counterparts. Most genes of DEGs associated with age or AD exhibit different trends between humans and mice. Pseudotime analyses demonstrate varying cell density trends in microglial subpopulations, depending on age or AD across species.ConclusionsMouse Apoe and Cell_Apoe maybe serve as proxies for studying human AD, while Cx3cr1 and Cell_Cx3cr1 are suitable for human aging studies. However, AD mouse models (App_NL_G_F) have limitations in studying human genes like IL1RAPL1 and SPP1 related to AD. Thus, mouse models cannot fully replace human samples for AD and aging research.

Dataset for scRNA-seq analysis guide

• `data.zip` unzips into a directory with the same name containing h5files i.e. counts matrix for creating Seurat object
  • There is a total of 16 files, 8 for NBM, 8 for CML
  • For the NBM donors, the 8 files belong to 4 donors, each with CD34pos and CD34neg
  • For the CML donors, the 8 files belong to 4 patients, each with CD34pos and CD34neg
• `bmref_azimuth.zip` unzips into a directory with the same name, containing files required by Azimuth to perform label transfer on bone marrow data, namely the following files:
  • idx.annoy
  • ref.Rds
  • leukaemiaGeneSet.txt
• `bmref_celldex` unzips into a directory with the same nam,e containing files required by SingleR to perform annotation on bone marrow data, namely the following files:
  • NovershternHem.rds

Remark: For trajectory inference discussion for that dataset, see paper: https://www.mdpi.com/1099-4300/22/11/1274 "Minimum Spanning vs. Principal Trees for Structured Approximations of Multi-Dimensional Datasets Alexander Chervov, Jonathan Bac and Andrei Zinovyev

For cell cycle analysis see: https://arxiv.org/abs/2208.05229 "Computational challenges of cell cycle analysis using single cell transcriptomics" Alexander Chervov, Andrei Zinovyev

Data and Context

Data - results of single cell RNA sequencing, i.e. rows - correspond to cells, columns to genes (or vice versa). value of the matrix shows how strong is "expression" of the corresponding gene in the corresponding cell. https://en.wikipedia.org/wiki/Single-cell_transcriptomics

See tutorials: https://scanpy.readthedocs.io/en/stable/tutorials.html ("Scanpy" - main Python package to work with scRNA-seq data). Or https://satijalab.org/seurat/ "Seurat" - "R" package

Particular data: Gene expressions count matrix. Single cell RNA sequencing data. 447 cells , 24748 genes Mouse Liver Hepatoblast in vivo.

Paper: Hepatology. 2017 Nov;66(5):1387-1401. doi: 10.1002/hep.29353. Epub 2017 Sep 29. A single-cell transcriptomic analysis reveals precise pathways and regulatory mechanisms underlying hepatoblast differentiation Li Yang 1 2 , Wei-Hua Wang 1 2 , Wei-Lin Qiu 1 3 , Zhen Guo 1 , Erfei Bi 4 , Cheng-Ran Xu 1

Data: GSE90047 https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE90047 Downloaded from: https://cytotrace.stanford.edu/#shiny-tab-dataset_download

Related datasets:

Other single cell RNA seq datasets can be found on kaggle: Look here: https://www.kaggle.com/alexandervc/datasets Or search kaggle for "scRNA-seq"

Inspiration

Single cell RNA sequencing is important technology in modern biology, see e.g. "Eleven grand challenges in single-cell data science" https://genomebiology.biomedcentral.com/articles/10.1186/s13059-020-1926-6

Also see review : Nature. P. Kharchenko: "The triumphs and limitations of computational methods for scRNA-seq" https://www.nature.com/articles/s41592-021-01171-x

Search scholar.google "challenges in single cell rna sequencing" https://scholar.google.fr/scholar?q=challenges+in+single+cell+rna+sequencing&hl=en&as_sdt=0&as_vis=1&oi=scholart gives many interesting and highly cited articles

(Cited 968) Computational and analytical challenges in single-cell transcriptomics Oliver Stegle, Sarah A. Teichmann, John C. Marioni Nat. Rev. Genet., 16 (3) (2015), pp. 133-145 https://www.nature.com/articles/nrg3833

Challenges in unsupervised clustering of single-cell RNA-seq data https://www.nature.com/articles/s41576-018-0088-9 Review Article 07 January 2019 Vladimir Yu Kiselev, Tallulah S. Andrews & Martin Hemberg Nature Reviews Genetics volume 20, pages273–282 (2019)

Challenges and emerging directions in single-cell analysis https://link.springer.com/article/10.1186/s13059-017-1218-y Published: 08 May 2017 Guo-Cheng Yuan, Long Cai, Michael Elowitz, Tariq Enver, Guoping Fan, Guoji Guo, Rafael Irizarry, Peter Kharchenko, Junhyong Kim, Stuart Orkin, John Quackenbush, Assieh Saadatpour, Timm Schroeder, Ramesh Shivdasani & Itay Tirosh Genome Biology volume 18, Article number: 84 (2017)

Single-Cell RNA Sequencing in Cancer: Lessons Learned and Emerging Challenges https://www.sciencedirect.com/science/article/pii/S1097276519303569 Molecular Cell Volume 75, Issue 1, 11 July 2019, Pages 7-12 Journal home page for Molecular Cell

The demo datasets for scMetabolismThe demo data is the dataset of Peripheral Blood Mononuclear Cells (PBMC) from 10X Genomics open access dataset (~2,700 single cells, also used by Seurat tutorial).

Integration Skript:

library(Seurat)
library(tidyverse)
library(Matrix)

#cite <- readRDS("C:/Users/alex/sciebo/ALL_NGS/scRNAseq/scRNAseq/Merge AAA mit Cite AAA/Cite_seq_v0.41.rds")
#CD45 <- readRDS("C:/Users/alex/sciebo/ALL_NGS/scRNAseq/scRNAseq/Schrader/Fertige_Analysen/TS_d5_paper/CD45.rds")
AAA <- readRDS("C:/Users/alex/sciebo/AAA_Zhao_v4.rds")
cite <- readRDS("C:/Users/alex/sciebo/CITE_Seq_v0.5.rds")
all4 <- readRDS("C:/Users/alex/sciebo/ALL_NGS/scRNAseq/scRNAseq/Schrader/Fertige_Analysen/Schrader_All4_Rohanalyse/all4_220228.rds")

#fuse lists
c <- list(cite, all4, AAA)
names(c) <- c("cite", "all4", "AAA")

pancreas.list <- c[c("cite", "all4", "AAA")]
for (i in 1:length(pancreas.list)) {
pancreas.list[[i]] <- SCTransform(pancreas.list[[i]], verbose = FALSE)
}

pancreas.features <- SelectIntegrationFeatures(object.list = pancreas.list, nfeatures = 3000)
#options(future.globals.maxSize= 6091289600)
#pancreas.list <- PrepSCTIntegration(object.list = pancreas.list, anchor.features = pancreas.features,
#verbose = FALSE) #future.globals.maxsize was to low. changed it to options(future.globals.maxSize= 1091289600)
#identify anchors

#alternative from tutorial (https://satijalab.org/seurat/articles/integration_introduction.html)
#memory.limit(9999999999)
features <- SelectIntegrationFeatures(object.list = pancreas.list, nfeatures = 3000)
pancreas.list <- PrepSCTIntegration(object.list = pancreas.list, anchor.features = features)
pancreas.anchors <- FindIntegrationAnchors(object.list = pancreas.list, normalization.method = "SCT", anchor.features = pancreas.features, verbose = FALSE)
pancreas.integrated <- IntegrateData(anchorset = pancreas.anchors, normalization.method = "SCT",
verbose = FALSE)

setwd("C:/Users/alex/sciebo/ALL_NGS/scRNAseq/scRNAseq/Schrader/Fertige_Analysen/TS_d5_paper")

saveRDS(pancreas.integrated, file = "integrated_AAA_Cite_AMI.rds")

saveRDS(cd45, file = "integrated_AAA_Cite_CD45.rds")

seurat <- pancreas.integrated

#seurat <- readRDS("C:/Users/alex/sciebo/ALL_NGS/scRNAseq/scRNAseq/Schrader/Fertige_Analysen/TS_d5_paper/integrated_d5_cite.rds")

DefaultAssay(object = seurat) <- "integrated"
seurat <- FindVariableFeatures(seurat, selection.method = "vst", nfeatures = 3000)
seurat <- ScaleData(seurat, verbose = FALSE)
seurat <- RunPCA(seurat, npcs = 30, verbose = FALSE)
seurat <- FindNeighbors(seurat, dims = 1:30)
seurat <- FindClusters(seurat, resolution = 0.5)
seurat <- RunUMAP(seurat, reduction = "pca", dims = 1:30)
DimPlot(seurat, reduction = "umap", split.by = "treatment") + NoLegend()

DimPlot(seurat, label = T, repel = T) + NoLegend()

DefaultAssay(object = seurat) <- "ADT"
adt_marker_integrated <- FindAllMarkers(seurat, logfc.threshold = 0.3)
write.csv(adt_marker_integrated, file = "adt_marker_all4_integrated.csv")

DefaultAssay(object = seurat) <- "RNA"
RNA_marker_integrated <- FindAllMarkers(seurat, logfc.threshold = 0.5)
write.csv(RNA_marker_integrated, file = "RNA_marker_all4_integrated.csv")

DimPlot(seurat, label = T, repel = T, split.by = "tissue") + NoLegend()

FeaturePlot(seurat, features = "Cd40", order = T, label = T)
FeaturePlot(seurat, features = "Ms.CD40", order = T, label = T)

#####
#leanup:
> seurat@meta.data[["sen_score1"]] <- NULL
> seurat@meta.data[["sen_score2"]] <- NULL
> seurat@meta.data[["sen_score3"]] <- NULL
> seurat@meta.data[["sen_score4"]] <- NULL
> seurat@meta.data[["sen_score5"]] <- NULL
> seurat@meta.data[["sen_score6"]] <- NULL
> seurat@meta.data[["sen_score7"]] <- NULL
> seurat@meta.data[["pANN_0.25_0.1_1211"]] <- NULL
> seurat@meta.data[["DF.classifications_0.25_0.1_1211"]] <- NULL
> seurat@meta.data[["DF.classifications_0.25_0.1_466"]] <- NULL
> seurat@assays[["prediction.score.celltype"]] <- NULL
> seurat@meta.data[["predicted.celltype"]] <- NULL
> seurat@meta.data[["DF.classifications_0.25_0.1_184"]] <- NULL
> seurat@meta.data[["DF.classifications_0.25_0.1_953"]] <- NULL
> seurat@meta.data[["integrated_snn_res.3"]] <- NULL
> seurat@meta.data[["RNA_snn_res.3"]] <- NULL
> seurat@meta.data[["SingleR"]] <- NULL
> seurat@meta.data[["SingleR_fine"]] <- NULL
> seurat@meta.data[["ImmGen"]] <- NULL
> seurat@meta.data[["ImmGen_fine"]] <- NULL
> seurat@meta.data[["percent.mt"]] <- NULL
> seurat@meta.data[["nCount_integrated"]] <- NULL
> seurat@meta.data[["nFeature_integrated"]] <- NULL
> seurat@meta.data[["S.Score"]] <- NULL
> seurat@meta.data[["G2M.Score"]] <- NULL
> seurat@meta.data[["Phase"]] <- NULL
> seurat@meta.data[["sen_score8"]] <- NULL
> seurat@meta.data[["sen_score9"]] <- NULL
> seurat@meta.data[["sen_score10"]] <- NULL
> seurat@meta.data[["sen_score11"]] <- NULL
> seurat@meta.data[["sen_score12"]] <- NULL
> seurat@meta.data[["sen_score13"]] <- NULL
> seurat@meta.data[["sen_score14"]] <- NULL
> seurat@meta.data[["sen_score15"]] <- NULL
> seurat@meta.data[["sen_score16"]] <- NULL
> seurat@meta.data[["sen_score17"]] <- NULL
> seurat@meta.data[["sen_score18"]] <- NULL
> seurat@meta.data[["sen_score19"]] <- NULL
seurat@meta.data[["pANN_0.25_0.1_184"]] <- NULL
seurat@meta.data[["pANN_0.25_0.1_953"]] <- NULL
seurat@meta.data[["pANN_0.25_0.1_466"]] <- NULL

Remark: See paper: https://arxiv.org/abs/2208.05229 results on cell cycle analysis discussed there. "Computational challenges of cell cycle analysis using single cell transcriptomics" Alexander Chervov, Andrei Zinovyev

Data and Context

Data - results of single cell RNA sequencing, i.e. rows - correspond to cells, columns to genes (or vice versa). value of the matrix shows how strong is "expression" of the corresponding gene in the corresponding cell. https://en.wikipedia.org/wiki/Single-cell_transcriptomics

See tutorials: https://scanpy.readthedocs.io/en/stable/tutorials.html ("Scanpy" - main Python package to work with scRNA-seq data). Or https://satijalab.org/seurat/ "Seurat" - "R" package

Particular data: Paper: CENP-A overexpression promotes distinct fates in human cells, depending on p53 status Daniel Jeffery, Alberto Gatto, Katrina Podsypanina, Charlène Renaud-Pageot, Rebeca Ponce Landete, Lorraine Bonneville, Marie Dumont, Daniele Fachinetti & Geneviève Almouzni https://www.nature.com/articles/s42003-021-01941-5

Data: https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-9861/

Related datasets:

Other single cell RNA seq datasets can be found on kaggle: Look here: https://www.kaggle.com/alexandervc/datasets Or search kaggle for "scRNA-seq"

Inspiration

Single cell RNA sequencing is important technology in modern biology, see e.g. "Eleven grand challenges in single-cell data science" https://genomebiology.biomedcentral.com/articles/10.1186/s13059-020-1926-6

Also see review : Nature. P. Kharchenko: "The triumphs and limitations of computational methods for scRNA-seq" https://www.nature.com/articles/s41592-021-01171-x

Search scholar.google "challenges in single cell rna sequencing" https://scholar.google.fr/scholar?q=challenges+in+single+cell+rna+sequencing&hl=en&as_sdt=0&as_vis=1&oi=scholart gives many interesting and highly cited articles

(Cited 968) Computational and analytical challenges in single-cell transcriptomics Oliver Stegle, Sarah A. Teichmann, John C. Marioni Nat. Rev. Genet., 16 (3) (2015), pp. 133-145 https://www.nature.com/articles/nrg3833

Challenges in unsupervised clustering of single-cell RNA-seq data https://www.nature.com/articles/s41576-018-0088-9 Review Article 07 January 2019 Vladimir Yu Kiselev, Tallulah S. Andrews & Martin Hemberg Nature Reviews Genetics volume 20, pages273–282 (2019)

Challenges and emerging directions in single-cell analysis https://link.springer.com/article/10.1186/s13059-017-1218-y Published: 08 May 2017 Guo-Cheng Yuan, Long Cai, Michael Elowitz, Tariq Enver, Guoping Fan, Guoji Guo, Rafael Irizarry, Peter Kharchenko, Junhyong Kim, Stuart Orkin, John Quackenbush, Assieh Saadatpour, Timm Schroeder, Ramesh Shivdasani & Itay Tirosh Genome Biology volume 18, Article number: 84 (2017)

Single-Cell RNA Sequencing in Cancer: Lessons Learned and Emerging Challenges https://www.sciencedirect.com/science/article/pii/S1097276519303569 Molecular Cell Volume 75, Issue 1, 11 July 2019, Pages 7-12 Journal home page for Molecular Cell

This repository hosts example data for reproducible analysis of intra- and intercellular signaling in single cell RNA sequencing (scRNAseq) data based on transcription factor (TF) activation. We demonstrate analysis using dominoSignal on the 10X Genomics Peripheral Blood Mononuclear Cells (PBMC) data set of 2,700 cells PBMC3K. scRNA-seq data is preprocessed following the Satija Lab's Guided Clustering Tutorial. Quantification of TF activation is conducted using pySCENIC. For more details on how this analysis is conducted, please refer to the vignettes in the dominoSignal package.