Spatial heterogeneity and interfacial signaling hub function of CPTCs across the ventral body wall continuum

Cd34+ Pdgfra+ Telocytes (CPTCs) are interstitial stromal cells implicated in long-distance intercellular communication, yet their role in bridging the distinct anatomical layers of the abdominal wall remains undefined. In this study, we combined single-cell RNA sequencing with functional assays to map the CPTC landscape across the skin, superficial fascia (SF), and deep fascia (DF), validating our findings through immunofluorescence and transmission electron microscopy. We identified a hierarchical stromal organization where CPTCs display layer-specific transcription factor networks tailored to local niches, co-existing with a conserved adhesion program. Notably, SF-CPTCs were characterized as an interfacial signaling hub with superior developmental plasticity. Ligand-receptor interaction analysis predicted that SF-CPTCs mediate cross-layer communication via the Wnt and Nectin pathways. We validated this mechanism using a sequential co-culture model, showing that SF-CPTCs integrate upstream signals to regulate target gene expression in adjacent layers. Primed SF-CPTCs significantly upregulated Lrp6 and Myc in deep fascia-resident myosatellite cells and induced Nectin2 and Ctnnb1 in cutaneous keratinocytes, whereas unprimed cells did not. Collectively, our data demonstrate that SF-CPTCs operate as a dynamic signaling gateway, integrating the skin and muscle compartments into a unified functional unit.