Fig. 1

Adipocytes are present in human granulation tissue of chronic wounds. a Histology of a representative granulation tissue section isolated from a 51-year-old patient (male) with a chronic lower limb wound and stained with hematoxylin and eosin (H&E) and PLIN1 (red staining). Areas highlighted are at higher magnification and indicate the presence of single (i) and clustered adipocytes (ii). b Intra-vital confocal microscopy of unfixed granulation tissue (same patient, left panel) and intact fat tissue (30-year-old male patient, right panel) stained with neutral lipid sensitive dye BODIPY493/503 (green), CF®555-labbeled wheat germ agglutinin to highlight N-acetyl-d-glucosamine and sialic acid present in heterogeneous polysaccharides (e.g., hyaluronan) of extracellular matrices (ECM), and Hoechst 33342 staining for nuclei (blue). c Double staining of representative sections from granulation tissue (left panel) or intact fat tissue (right panel) with CD68 (AF488, green) and PLIN (AF555, red). Nuclei (blue) were counterstained with Hoechst 33342. The arrows heads indicate CD68 positive cells (macrophages) in close proximity to adipocytes. d Single-cell suspension from granulation tissue was subjected to in vitro differentiation for 14 days. Lipid droplets and nuclei were visualized by BODIPY493/503 (green) and Hoechst 33342 (blue), respectively