757 Wound healing in aged skin exhibits systems-level alterations in cellular composition and cell-cell communication

Delayed or impaired wound healing in aging skin poses major medical, social, and economic challenges, yet a systematic understanding of the contributing cellular molecular alterations is lacking. In this work, we use single-cell RNA sequencing to interrogate differences across epithelial, fibroblast, immune cell types wounds young aged animals. We have identified changes their subset compositions profiles during healing. Our data uncover more inflammatory phenotype from mice, featuring altered previously unknown Arg1Hi macrophage subset, compared counterparts. Using CellChat algorithm examine signaling wounds, found communication between fibroblasts macrophages. Particularly, osteospontin (OPN) expression elevated macrophages mid- late-stages might contribute delayed skin. study unveils composition cell-cell for future functional studies