Interaction analysis retrieves well-known and novel molecular interaction partners in the context of HSPC homeostasis. (A) Interaction analysis pipeline. (B) Example of interactions and respective interaction scores for the LT-HSC/MSC (BM plus bone) pair. (C) Left panel, Relationship between mean expression of receptors in HSPCs and scores of interactions involving indicated ligands. Right panel, Relationship between mean expression of ligands in niche cells and scores of interactions involving indicated receptors. (D) Plot shows mean receptor rank within HSPCs (x-axis) vs the highest rank of the respective ligands in any niche cell (y-axis), green dots are, from left to right, Tek, Cxcr4, Itga4, Itgb1, Kit. (E) Hierarchical clustering of HSPC/niche cell pairs based on interaction scores.