S5 — Downstream (Neighborhood + Communication)
Goal
Quantify cell-type co-localization with neighborhood enrichment, and infer spatially proximal cell-cell communication with CellChat v2.
Prerequisites
- Deconvolved Visium h5ad from S4 with cell-type proportions (for both analyses).
- R + CellChat v2 for communication (see
install_r_packages_spatial.R).
Steps
- Neighborhood enrichment:
spatial_neighborhood_enrichment(adata_path=..., cell_type_key=..., output_path=..., plot_path=..., n_neighs=...)- Defaults:
n_neighs=6. - Output: enrichment z-score table + heatmap.
- Defaults:
- CellChat:
infer_spatial_cell_communication(st_h5ad=..., cell_type_key=..., output_dir=..., plot_path=..., r_script_path=..., species=...)species:"human"(default) or"mouse"— selects the CellChatDB.- Output: CellChat object, communication summary, network/heatmap plots.
Outputs
results/08_neighborhood/<sample>_enrichment.csv+ heatmap PNGresults/09_communication/<sample>_cellchat_*.png(network, heatmap, bubble)results/09_communication/<sample>_communication_summary.csv
Biological Interpretation
- Neighborhood: which cell-type pairs co-localize significantly (|z| > 2)? Does this match known tissue niches (e.g., tumor–macrophage, T cell–APC)?
- Communication: which ligand–receptor pairs dominate? Are they consistent with the tissue's known biology (e.g., immune checkpoint pairs in tumor)?
Stop for Review
Present interpretation using the template from the parent spatial-transcriptomics skill. This is the final stage — after review, produce the overall workflow summary.


