Spatial compartmentalization of signalling imparts source-specific functions on secreted factors

Abstract

Efficient regeneration requires multiple cell types acting in a coordination. To better understand the intercellular networks involved and how they change when regeneration fails, we profiled the transcriptome of hematopoietic, stromal, myogenic, and endothelial cells over 14 days following acute muscle damage. A time-resolved computational model of interactions was generated, and VEGFA-driven endothelial engagement was identified as a key differentiating feature in models of successful and failed regeneration. In addition, it revealed that the majority of secreted signals, including VEGFA, are simultaneously produced by multiple cell types. To test whether the cellular source of a factor determines its function, we deleted VEGFA from two cell types residing in close proximity, stromal and myogenic progenitors. By comparing responses to different types of damage, we found that myogenic and stromal VEGFA have distinct functions in regeneration. This suggests that spatial compartmentalization of signaling plays a key role in intercellular communication networks. HighlightsO_LILigand-receptor signaling redundancy during skeletal muscle regeneration C_LIO_LIInflammatory cells, and muscle and fibro/adipogenic progenitors produce VEGFA C_LIO_LIVEGFA from muscle progenitors control their proliferation after muscle damage C_LIO_LIVEGFA from FAP controls angiogenesis only after ischemic damage C_LI eTOC blurbGroppa et al. performed a novel time-resolved bioinformatics analysis that revealed extensive ligand-receptor redundancy among the cell types contributing to skeletal muscle regeneration. They focused on one of these pathways, and showed that VEGFA from different cell types has distinct roles in regeneration.