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Introduction

SpaTalk provides a comprehensive suite of visualization functions for exploring spatial transcriptomics data and cell-cell communication results. This vignette demonstrates the key plotting functions with real examples.

Setup

library(SpaTalk)
library(ggplot2)

# Load demo data
load(system.file("extdata", "starmap_data.rda", package = "SpaTalk"))
load(system.file("extdata", "starmap_meta.rda", package = "SpaTalk"))
data(lrpairs)
data(pathways)

# Create SpaTalk object
st_meta <- data.frame(
  cell = starmap_meta$cell,
  x = starmap_meta$x,
  y = starmap_meta$y
)

obj <- createSpaTalk(
  st_data = starmap_data,
  st_meta = st_meta,
  species = "Mouse",
  if_st_is_sc = TRUE,
  spot_max_cell = 1,
  celltype = starmap_meta$celltype
)

obj <- find_lr_path(obj, lrpairs, pathways, if_doParallel = FALSE)
#> Checking input data 
#> Begin to filter lrpairs and pathways 
#> ***Done*** 
#> 

# Show available cell types
cat("Available cell types:", paste(unique(starmap_meta$celltype), collapse = ", "), "\n")
#> Available cell types: eL2_3, eL6, Astro, PVALB, Endo, VIP, SST, Smc, eL4, Micro, Oligo, eL5, Reln, HPC

Spatial Cell Type Visualization

plot_st_celltype_all

Display all cell types in a single spatial plot. This is one of the most commonly used visualizations.

plot_st_celltype_all(
  object = obj,
  size = 1.2
)
All cell types in spatial context

All cell types in spatial context

plot_st_celltype

Visualize specific cell type distributions in spatial coordinates.

plot_st_celltype(
  object = obj,
  celltype = "eL6",
  size = 1.5
)
Spatial distribution of eL6 cells

Spatial distribution of eL6 cells

plot_st_celltype_density

Kernel density estimation of cell type spatial distributions.

plot_st_celltype_density(
  object = obj,
  celltype = "eL6",
  type = "contour"
)
Cell type density map for eL6

Cell type density map for eL6

Gene Expression Visualization

plot_st_gene

Visualize gene expression patterns in spatial coordinates.

# Get available genes
genes <- rownames(obj@data$rawdata)
cat("Total genes:", length(genes), "\n")
#> Total genes: 996

# Plot first available gene
plot_st_gene(
  object = obj,
  gene = genes[1],
  size = 1.5
)
Spatial gene expression

Spatial gene expression

Advanced Visualizations (After CCI Analysis)

The following visualizations require running dec_cci() or dec_cci_all() first:

# Run CCI analysis for demonstration
obj <- dec_cci(
  object = obj,
  celltype_sender = "eL6",
  celltype_receiver = "PVALB",
  if_doParallel = FALSE
)
#> Begin to find LR pairs 
#> 

# Check results
if(nrow(obj@lrpair) > 0) {
  cat("Found", nrow(obj@lrpair), "significant LR pairs\n")
  print(head(obj@lrpair[, c("ligand", "receptor", "lr_co_ratio", "score")]))
}
#> Found 1 significant LR pairs
#>   ligand receptor lr_co_ratio     score
#> 5  Inhba   Acvr1c   0.1666667 0.8541642

plot_ccdist

Distribution of distances between interacting cell types.

plot_ccdist(
  object = obj,
  celltype_sender = "eL6",
  celltype_receiver = "PVALB"
)
Cell-cell distance distribution between eL6 and PVALB

Cell-cell distance distribution between eL6 and PVALB

plot_lrpair

Spatial visualization of specific ligand-receptor pair interactions (if significant pairs found).

if(nrow(obj@lrpair) > 0) {
  lr <- obj@lrpair[1, ]
  plot_lrpair(
    object = obj,
    ligand = lr$ligand,
    receptor = lr$receptor,
    celltype_sender = "eL6",
    celltype_receiver = "PVALB",
    size = 1.2
  )
} else {
  cat("No significant LR pairs found for visualization\n")
}
Spatial LR pair visualization

Spatial LR pair visualization

Customization Tips

Custom Themes

SpaTalk uses ggplot2 for all visualizations. You can easily customize:

p <- plot_st_celltype_all(obj, size = 1)

p + 
  theme_minimal() +
  theme(
    legend.position = "bottom",
    plot.title = element_text(hjust = 0.5, size = 14, face = "bold")
  ) +
  labs(title = "STARmap Cell Type Distribution")
Customized plot with different theme

Customized plot with different theme

Summary of Visualization Functions

Function Description Input Required
plot_st_celltype Single cell type spatial SpaTalk object
plot_st_celltype_all All cell types spatial SpaTalk object
plot_st_celltype_percent Pie chart per spot Deconvolved object
plot_st_celltype_density Density heatmap SpaTalk object
plot_st_gene Gene expression spatial SpaTalk object
plot_st_pie Pie chart composition Deconvolved object
plot_cci_lrpairs CCI chord diagram After dec_cci
plot_lrpair LR pair spatial After dec_cci
plot_lrpair_vln LR violin plot After dec_cci
plot_lr_path LR-pathway network After dec_cci
plot_path2gene Pathway heatmap After dec_cci
plot_st_cor_heatmap Correlation heatmap SpaTalk object
plot_ccdist Distance distribution SpaTalk object

Session Info

sessionInfo()
#> R version 4.4.0 (2024-04-24)
#> Platform: aarch64-apple-darwin20
#> Running under: macOS 15.6.1
#> 
#> Matrix products: default
#> BLAS:   /Library/Frameworks/R.framework/Versions/4.4-arm64/Resources/lib/libRblas.0.dylib 
#> LAPACK: /Library/Frameworks/R.framework/Versions/4.4-arm64/Resources/lib/libRlapack.dylib;  LAPACK version 3.12.0
#> 
#> locale:
#> [1] C
#> 
#> time zone: Asia/Shanghai
#> tzcode source: internal
#> 
#> attached base packages:
#> [1] parallel  stats     graphics  grDevices utils     datasets  methods  
#> [8] base     
#> 
#> other attached packages:
#> [1] SpaTalk_2.0.0     doParallel_1.0.17 iterators_1.0.14  foreach_1.5.2    
#> [5] ggalluvial_0.12.5 ggplot2_4.0.1    
#> 
#> loaded via a namespace (and not attached):
#>   [1] RColorBrewer_1.1-3     jsonlite_2.0.0         magrittr_2.0.4        
#>   [4] spatstat.utils_3.2-1   farver_2.1.2           rmarkdown_2.30        
#>   [7] fs_1.6.6               ragg_1.5.0             vctrs_0.7.0           
#>  [10] ROCR_1.0-11            spatstat.explore_3.6-0 rstatix_0.7.3         
#>  [13] htmltools_0.5.9        progress_1.2.3         broom_1.0.11          
#>  [16] Formula_1.2-5          sass_0.4.10            sctransform_0.4.3     
#>  [19] parallelly_1.46.1      KernSmooth_2.23-26     bslib_0.9.0           
#>  [22] htmlwidgets_1.6.4      desc_1.4.3             ica_1.0-3             
#>  [25] plyr_1.8.9             plotly_4.11.0          zoo_1.8-15            
#>  [28] cachem_1.1.0           igraph_2.2.1           mime_0.13             
#>  [31] lifecycle_1.0.5        pkgconfig_2.0.3        Matrix_1.7-4          
#>  [34] R6_2.6.1               fastmap_1.2.0          fitdistrplus_1.2-4    
#>  [37] future_1.69.0          shiny_1.12.1           digest_0.6.39         
#>  [40] patchwork_1.3.2        Seurat_4.4.0           tensor_1.5.1          
#>  [43] irlba_2.3.5.1          textshaping_1.0.4      ggpubr_0.6.2          
#>  [46] labeling_0.4.3         progressr_0.18.0       spatstat.sparse_3.1-0 
#>  [49] httr_1.4.7             polyclip_1.10-7        abind_1.4-8           
#>  [52] compiler_4.4.0         withr_3.0.2            backports_1.5.0       
#>  [55] S7_0.2.1               carData_3.0-5          ggforce_0.5.0         
#>  [58] ggsignif_0.6.4         MASS_7.3-65            rappdirs_0.3.4        
#>  [61] ggsci_4.2.0            tools_4.4.0            lmtest_0.9-40         
#>  [64] otel_0.2.0             scatterpie_0.2.6       httpuv_1.6.16         
#>  [67] future.apply_1.20.1    goftest_1.2-3          glue_1.8.0            
#>  [70] nlme_3.1-168           promises_1.5.0         grid_4.4.0            
#>  [73] Rtsne_0.17             cluster_2.1.8.1        reshape2_1.4.5        
#>  [76] generics_0.1.4         isoband_0.3.0          gtable_0.3.6          
#>  [79] spatstat.data_3.1-9    tzdb_0.5.0             tidyr_1.3.2           
#>  [82] data.table_1.18.0      hms_1.1.4              car_3.1-3             
#>  [85] sp_2.2-0               spatstat.geom_3.6-1    RcppAnnoy_0.0.23      
#>  [88] ggrepel_0.9.6          RANN_2.6.2             pillar_1.11.1         
#>  [91] stringr_1.6.0          yulab.utils_0.2.3      ggExtra_0.11.0        
#>  [94] later_1.4.5            splines_4.4.0          tweenr_2.0.3          
#>  [97] dplyr_1.1.4            lattice_0.22-7         survival_3.8-3        
#> [100] deldir_2.0-4           tidyselect_1.2.1       miniUI_0.1.2          
#> [103] pbapply_1.7-4          knitr_1.51             gridExtra_2.3         
#> [106] scattermore_1.2        xfun_0.56              matrixStats_1.5.0     
#> [109] pheatmap_1.0.13        stringi_1.8.7          ggfun_0.2.0           
#> [112] lazyeval_0.2.2         yaml_2.3.12            evaluate_1.0.5        
#> [115] codetools_0.2-20       tibble_3.3.1           cli_3.6.5             
#> [118] uwot_0.2.4             xtable_1.8-4           reticulate_1.44.1     
#> [121] systemfonts_1.3.1      jquerylib_0.1.4        dichromat_2.0-0.1     
#> [124] Rcpp_1.1.1             globals_0.18.0         spatstat.random_3.4-3 
#> [127] png_0.1-8              spatstat.univar_3.1-6  readr_2.1.6           
#> [130] pkgdown_2.1.3          NNLM_0.4.4             prettyunits_1.2.0     
#> [133] listenv_0.10.0         viridisLite_0.4.2      scales_1.4.0          
#> [136] ggridges_0.5.7         SeuratObject_4.1.4     leiden_0.4.3.1        
#> [139] purrr_1.2.1            crayon_1.5.3           rlang_1.1.7           
#> [142] cowplot_1.2.0