mini_seqfish#
- Date:
2022-09-16
Start Giotto#
# Ensure Giotto Suite is installed.
if(!"Giotto" %in% installed.packages()) {
devtools::install_github("drieslab/Giotto@suite")
}
# Ensure GiottoData, a small, helper module for tutorials, is installed.
if(!"GiottoData" %in% installed.packages()) {
devtools::install_github("drieslab/GiottoData")
}
library(Giotto)
# Ensure the Python environment for Giotto has been installed.
genv_exists = checkGiottoEnvironment()
if(!genv_exists){
# The following command need only be run once to install the Giotto environment.
installGiottoEnvironment()
}
Set Giotto instructions (optional)#
library(Giotto)
library(GiottoData)
# to automatically save figures in save_dir set save_plot to TRUE
temp_dir = getwd()
myinstructions = createGiottoInstructions(save_dir = temp_dir,
save_plot = FALSE,
show_plot = TRUE)
1. Create a Giotto object#
The minimum requirements are
matrix with expression information (or path to)
x,y(,z) coordinates for cells or spots (or path to)
# download data
data_directory = paste0(temp_dir, '/data/')
getSpatialDataset(dataset = 'mini_seqFISH', directory = data_directory, method = 'wget')
# giotto object
expr_path = paste0(data_directory, "seqfish_field_expr.txt.gz")
loc_path = paste0(data_directory, "seqfish_field_locs.txt")
seqfish_mini = createGiottoObject(expression = expr_path,
spatial_locs = loc_path,
instructions = myinstructions)
How to work with Giotto instructions that are part of your Giotto object:
show the instructions associated with your Giotto object with showGiottoInstructions()
change one or more instructions with changeGiottoInstructions()
replace all instructions at once with replaceGiottoInstructions()
read or get a specific Giotto instruction with readGiottoInstructions()
# show instructions associated with giotto object (seqfish_mini)
showGiottoInstructions(seqfish_mini)
2. Processing steps#
filter genes and cells based on detection frequencies
normalize expression matrix (log transformation, scaling factor and/or z-scores)
add cell and gene statistics (optional)
adjust expression matrix for technical covariates or batches (optional). These results will be stored in the custom slot.
seqfish_mini = filterGiotto(gobject = seqfish_mini,
expression_threshold = 0.5,
feat_det_in_min_cells = 20,
min_det_feats_per_cell = 0)
seqfish_mini = normalizeGiotto(gobject = seqfish_mini, scalefactor = 6000, verbose = T)
seqfish_mini = addStatistics(gobject = seqfish_mini)
seqfish_mini = adjustGiottoMatrix(gobject = seqfish_mini,
expression_values = c('normalized'),
covariate_columns = c('nr_feats', 'total_expr'))
3. Dimension reduction#
identify highly variable features (HVF)
seqfish_mini = calculateHVF(gobject = seqfish_mini)

perform PCA
identify number of significant principal components (PCs)
seqfish_mini = runPCA(gobject = seqfish_mini)
screePlot(seqfish_mini, ncp = 20)

plotPCA(seqfish_mini)

run UMAP and/or t-SNE on PCs (or directly on matrix)
seqfish_mini = runUMAP(seqfish_mini, dimensions_to_use = 1:5, n_threads = 2)
plotUMAP(gobject = seqfish_mini)

seqfish_mini = runtSNE(seqfish_mini, dimensions_to_use = 1:5)
plotTSNE(gobject = seqfish_mini)

4. Clustering#
create a shared (default) nearest network in PCA space (or directly on matrix)
cluster on nearest network with Leiden or Louvain (k-means and hclust are alternatives)
seqfish_mini = createNearestNetwork(gobject = seqfish_mini, dimensions_to_use = 1:5, k = 5)
seqfish_mini = doLeidenCluster(gobject = seqfish_mini, resolution = 0.4, n_iterations = 1000)
# visualize UMAP cluster results
plotUMAP(gobject = seqfish_mini, cell_color = 'leiden_clus', show_NN_network = T, point_size = 2.5)

# visualize UMAP and spatial results
spatDimPlot(gobject = seqfish_mini, cell_color = 'leiden_clus', spat_point_shape = 'voronoi')

# heatmap and dendrogram
showClusterHeatmap(gobject = seqfish_mini, cluster_column = 'leiden_clus')

The following step requires the installation of {ggdendro}.
# install.packages('ggdendro')
library(ggdendro)
showClusterDendrogram(seqfish_mini, h = 0.5, rotate = T, cluster_column = 'leiden_clus')

5. Differential expression#
gini_markers = findMarkers_one_vs_all(gobject = seqfish_mini,
method = 'gini',
expression_values = 'normalized',
cluster_column = 'leiden_clus',
min_feats = 20,
min_expr_gini_score = 0.5,
min_det_gini_score = 0.5)
# get top 2 genes per cluster and visualize with violin plot
topgenes_gini = gini_markers[, head(.SD, 2), by = 'cluster']
violinPlot(seqfish_mini, feats = topgenes_gini$feats[1:4], cluster_column = 'leiden_clus')

# get top 6 genes per cluster and visualize with heatmap
topgenes_gini2 = gini_markers[, head(.SD, 6), by = 'cluster']
plotMetaDataHeatmap(seqfish_mini, selected_feats = topgenes_gini2$feats,
metadata_cols = c('leiden_clus'))

6. Cell type annotation#
clusters_cell_types = c('cell A', 'cell B', 'cell C', 'cell D',
'cell E', 'cell F', 'cell G', 'cell H')
names(clusters_cell_types) = 1:8
seqfish_mini = annotateGiotto(gobject = seqfish_mini,
annotation_vector = clusters_cell_types,
cluster_column = 'leiden_clus',
name = 'cell_types')
# check new cell metadata
pDataDT(seqfish_mini)
# visualize annotations
spatDimPlot(gobject = seqfish_mini, cell_color = 'cell_types',
spat_point_size = 3, dim_point_size = 3)

# heatmap
topgenes_heatmap = gini_markers[, head(.SD, 4), by = 'cluster']
plotHeatmap(gobject = seqfish_mini,
feats = topgenes_heatmap$feats,
feat_order = 'custom',
feat_custom_order = unique(topgenes_heatmap$feats),
cluster_column = 'cell_types',
legend_nrows = 1)

7. Spatial grid#
Create a grid based on defined step sizes in the x,y(,z) axes.
seqfish_mini = createSpatialGrid(gobject = seqfish_mini,
sdimx_stepsize = 300,
sdimy_stepsize = 300,
minimum_padding = 50)
showGiottoSpatGrids(seqfish_mini)
# visualize grid
spatPlot(gobject = seqfish_mini, show_grid = T, point_size = 1.5)

8. Spatial network#
visualize information about the default Delaunay network
create a spatial Delaunay network (default)
create a spatial kNN network
plotStatDelaunayNetwork(gobject = seqfish_mini, maximum_distance = 400)

seqfish_mini = createSpatialNetwork(gobject = seqfish_mini, minimum_k = 2,
maximum_distance_delaunay = 400)
seqfish_mini = createSpatialNetwork(gobject = seqfish_mini, minimum_k = 2,
method = 'kNN', k = 10)
showGiottoSpatNetworks(seqfish_mini)
# visualize the two different spatial networks
spatPlot(gobject = seqfish_mini, show_network = T,
network_color = 'blue', spatial_network_name = 'Delaunay_network',
point_size = 2.5, cell_color = 'leiden_clus')

spatPlot(gobject = seqfish_mini, show_network = T,
network_color = 'blue', spatial_network_name = 'kNN_network',
point_size = 2.5, cell_color = 'leiden_clus')

9. Spatial genes#
Identify spatial genes with 3 different methods:
binSpect with k-means binarization (default)
binSpect with rank binarization
silhouetteRank
Visualize top 4 genes per method.
km_spatialgenes = binSpect(seqfish_mini)
spatFeatPlot2D(seqfish_mini, expression_values = 'scaled',
feats = km_spatialgenes[1:4]$feats,
point_shape = 'border', point_border_stroke = 0.1,
show_network = F, network_color = 'lightgrey', point_size = 2.5,
cow_n_col = 2)

rank_spatialgenes = binSpect(seqfish_mini, bin_method = 'rank')
spatFeatPlot2D(seqfish_mini, expression_values = 'scaled',
feats = rank_spatialgenes[1:4]$feats,
point_shape = 'border', point_border_stroke = 0.1,
show_network = F, network_color = 'lightgrey', point_size = 2.5,
cow_n_col = 2)

silh_spatialgenes = silhouetteRank(gobject = seqfish_mini) # TODO: suppress print output
spatFeatPlot2D(seqfish_mini, expression_values = 'scaled',
feats = silh_spatialgenes[1:4]$genes,
point_shape = 'border', point_border_stroke = 0.1,
show_network = F, network_color = 'lightgrey', point_size = 2.5,
cow_n_col = 2)

10. Spatial co-expression patterns#
Identify robust spatial co-expression patterns using the spatial network or grid and a subset of individual spatial genes.
calculate spatial correlation scores
cluster correlation scores
# 1. calculate spatial correlation scores
ext_spatial_genes = km_spatialgenes[1:500]$feats
spat_cor_netw_DT = detectSpatialCorFeats(seqfish_mini,
method = 'network',
spatial_network_name = 'Delaunay_network',
subset_feats = ext_spatial_genes)
# 2. cluster correlation scores
spat_cor_netw_DT = clusterSpatialCorFeats(spat_cor_netw_DT,
name = 'spat_netw_clus', k = 8)
heatmSpatialCorFeats(seqfish_mini, spatCorObject = spat_cor_netw_DT,
use_clus_name = 'spat_netw_clus')

netw_ranks = rankSpatialCorGroups(seqfish_mini,
spatCorObject = spat_cor_netw_DT,
use_clus_name = 'spat_netw_clus')

top_netw_spat_cluster = showSpatialCorFeats(spat_cor_netw_DT,
use_clus_name = 'spat_netw_clus',
selected_clusters = 6,
show_top_feats = 1)
cluster_genes_DT = showSpatialCorFeats(spat_cor_netw_DT,
use_clus_name = 'spat_netw_clus',
show_top_feats = 1)
cluster_genes = cluster_genes_DT$clus; names(cluster_genes) = cluster_genes_DT$feat_ID
seqfish_mini = createMetafeats(seqfish_mini,
feat_clusters = cluster_genes,
name = 'cluster_metagene')
spatCellPlot(seqfish_mini,
spat_enr_names = 'cluster_metagene',
cell_annotation_values = netw_ranks$clusters,
point_size = 1.5, cow_n_col = 3)

11. Spatial HMRF domains#
The following HMRF function requires {smfishHmrf} .
# remotes::install_bitbucket(repo = 'qzhudfci/smfishhmrf-r', ref='master')
library(smfishHmrf)
hmrf_folder = paste0(temp_dir,'/','11_HMRF/')
if(!file.exists(hmrf_folder)) dir.create(hmrf_folder, recursive = T)
# perform hmrf
my_spatial_genes = km_spatialgenes[1:100]$feats
HMRF_spatial_genes = doHMRF(gobject = seqfish_mini,
expression_values = 'scaled',
spatial_genes = my_spatial_genes,
spatial_network_name = 'Delaunay_network',
k = 9,
betas = c(28,2,2),
output_folder = paste0(hmrf_folder, '/', 'Spatial_genes/SG_top100_k9_scaled'))
# check and select hmrf
for(i in seq(28, 30, by = 2)) {
viewHMRFresults2D(gobject = seqfish_mini,
HMRFoutput = HMRF_spatial_genes,
k = 9, betas_to_view = i,
point_size = 2)
}
seqfish_mini = addHMRF(gobject = seqfish_mini,
HMRFoutput = HMRF_spatial_genes,
k = 9, betas_to_add = c(28),
hmrf_name = 'HMRF')
# visualize selected hmrf result
giotto_colors = Giotto:::getDistinctColors(9)
names(giotto_colors) = 1:9
spatPlot(gobject = seqfish_mini, cell_color = 'HMRF_k9_b.28',
point_size = 3, coord_fix_ratio = 1, cell_color_code = giotto_colors)

12. Cell neighborhood: cell-type/cell-type interactions#
set.seed(seed = 2841)
cell_proximities = cellProximityEnrichment(gobject = seqfish_mini,
cluster_column = 'cell_types',
spatial_network_name = 'Delaunay_network',
adjust_method = 'fdr',
number_of_simulations = 1000)
# barplot
cellProximityBarplot(gobject = seqfish_mini,
CPscore = cell_proximities,
min_orig_ints = 5, min_sim_ints = 5, p_val = 0.5)

## heatmap
cellProximityHeatmap(gobject = seqfish_mini, CPscore = cell_proximities,
order_cell_types = T, scale = T,
color_breaks = c(-1.5, 0, 1.5),
color_names = c('blue', 'white', 'red'))

# network
cellProximityNetwork(gobject = seqfish_mini, CPscore = cell_proximities,
remove_self_edges = T, only_show_enrichment_edges = T)

# network with self-edges
cellProximityNetwork(gobject = seqfish_mini, CPscore = cell_proximities,
remove_self_edges = F, self_loop_strength = 0.3,
only_show_enrichment_edges = F,
rescale_edge_weights = T,
node_size = 8,
edge_weight_range_depletion = c(1, 2),
edge_weight_range_enrichment = c(2,5))

Visualization of specific cell types#
# Option 1
spec_interaction = "cell D--cell F"
cellProximitySpatPlot2D(gobject = seqfish_mini,
interaction_name = spec_interaction,
show_network = T,
cluster_column = 'cell_types',
cell_color = 'cell_types',
cell_color_code = c('cell D' = 'lightblue', 'cell F' = 'red'),
point_size_select = 4, point_size_other = 2)

# Option 2: create additional metadata
seqfish_mini = addCellIntMetadata(seqfish_mini,
spat_unit = "cell",
spatial_network = 'Delaunay_network',
cluster_column = 'cell_types',
cell_interaction = spec_interaction,
name = 'D_F_interactions')
spatPlot(seqfish_mini, cell_color = 'D_F_interactions', legend_symbol_size = 3,
select_cell_groups = c('other_cell D', 'other_cell F', 'select_cell D', 'select_cell F'))

13. Cell neighborhood: interaction changed features#
## select top 25 highest expressing genes
gene_metadata = fDataDT(seqfish_mini)
plot(gene_metadata$nr_cells, gene_metadata$mean_expr)
plot(gene_metadata$nr_cells, gene_metadata$mean_expr_det)
quantile(gene_metadata$mean_expr_det)
high_expressed_genes = gene_metadata[mean_expr_det > 4]$feat_ID
## identify features (genes) that are associated with proximity to other cell types
ICFscoresHighGenes = findICF(gobject = seqfish_mini,
selected_feats = high_expressed_genes,
spatial_network_name = 'Delaunay_network',
cluster_column = 'cell_types',
diff_test = 'permutation',
adjust_method = 'fdr',
nr_permutations = 500,
do_parallel = T)
## visualize all genes
plotCellProximityFeats(seqfish_mini, icfObject = ICFscoresHighGenes, method = 'dotplot')

## filter genes
ICFscoresFilt = filterICF(ICFscoresHighGenes, min_cells = 2, min_int_cells = 2, min_fdr = 0.1,
min_spat_diff = 0.1, min_log2_fc = 0.1, min_zscore = 1)
## visualize subset of interaction changed genes (ICGs)
ICF_genes = c('Cpne2', 'Scg3', 'Cmtm3', 'Cplx1', 'Lingo1')
ICF_genes_types = c('cell E', 'cell D', 'cell D', 'cell G', 'cell E')
names(ICF_genes) = ICF_genes_types
plotICF(gobject = seqfish_mini,
icfObject = ICFscoresHighGenes,
source_type = 'cell A',
source_markers = c('Csf1r', 'Laptm5'),
ICF_feats = ICF_genes)

14. Cell neighborhood: ligand-receptor cell-cell communication#
LR_data = data.table::fread(paste0(data_directory, "mouse_ligand_receptors.txt"))
LR_data[, ligand_det := ifelse(mouseLigand %in% seqfish_mini@feat_ID[['rna']], T, F)]
LR_data[, receptor_det := ifelse(mouseReceptor %in% seqfish_mini@feat_ID[['rna']], T, F)]
LR_data_det = LR_data[ligand_det == T & receptor_det == T]
select_ligands = LR_data_det$mouseLigand
select_receptors = LR_data_det$mouseReceptor
## get statistical significance of gene pair expression changes based on expression ##
expr_only_scores = exprCellCellcom(gobject = seqfish_mini,
cluster_column = 'cell_types',
random_iter = 50,
feat_set_1 = select_ligands,
feat_set_2 = select_receptors)
## get statistical significance of gene pair expression changes upon cell-cell interaction
spatial_all_scores = spatCellCellcom(seqfish_mini,
spat_unit = 'cell',
feat_type = 'rna',
spatial_network_name = 'Delaunay_network',
cluster_column = 'cell_types',
random_iter = 50,
feat_set_1 = select_ligands,
feat_set_2 = select_receptors,
adjust_method = 'fdr',
do_parallel = T,
cores = 4,
verbose = 'none')
## * plot communication scores ####
## select top LR ##
selected_spat = spatial_all_scores[p.adj <= 0.5 & abs(log2fc) > 0.1 & lig_nr >= 2 & rec_nr >= 2]
data.table::setorder(selected_spat, -PI)
top_LR_ints = unique(selected_spat[order(-abs(PI))]$LR_comb)[1:33]
top_LR_cell_ints = unique(selected_spat[order(-abs(PI))]$LR_cell_comb)[1:33]
plotCCcomHeatmap(gobject = seqfish_mini,
comScores = spatial_all_scores,
selected_LR = top_LR_ints,
selected_cell_LR = top_LR_cell_ints,
show = 'LR_expr')

plotCCcomDotplot(gobject = seqfish_mini,
comScores = spatial_all_scores,
selected_LR = top_LR_ints,
selected_cell_LR = top_LR_cell_ints,
cluster_on = 'PI')

## * spatial vs rank ####
comb_comm = combCCcom(spatialCC = spatial_all_scores,
exprCC = expr_only_scores)
# top differential activity levels for ligand receptor pairs
plotRankSpatvsExpr(gobject = seqfish_mini,
comb_comm,
expr_rnk_column = 'exprPI_rnk',
spat_rnk_column = 'spatPI_rnk',
midpoint = 10)

## * recovery ####
## predict maximum differential activity
plotRecovery(gobject = seqfish_mini,
comb_comm,
expr_rnk_column = 'exprPI_rnk',
spat_rnk_column = 'spatPI_rnk',
ground_truth = 'spatial')

15. Export Giotto Analyzer to Viewer#
viewer_folder = paste0(temp_dir, '/', 'Mouse_cortex_viewer')
# select annotations, reductions and expression values to view in Giotto Viewer
exportGiottoViewer(gobject = seqfish_mini,
output_directory = viewer_folder,
factor_annotations = c('cell_types',
'leiden_clus',
'HMRF_k9_b.28'),
numeric_annotations = 'total_expr',
dim_reductions = c('umap'),
dim_reduction_names = c('umap'),
expression_values = 'scaled',
expression_rounding = 3,
overwrite_dir = T)