Project description:In this pilot study, we optimized diabetic foot ulcers (DFUs) single-cell profiling from debrided DFUs of underrepresented African American (AA) patients. The healing-DFUs were significantly enriched (P=0.03) with unique heterogenous Healing-associated Fibroblasts (HE-Fibro), expressing inflammation (CHI3L1), ECM-remodeling (MMP13, ASPN) and wound healing (NRG1, COL7A1) associated genes, validating our previous findings with surgically resected healer-DFUs. HE-Fibro/Fibro cells depicted significantly lower expression of key healing-associated CHIL3L1, and TIMP1 genes in AAs compared to Whites, signifying race-associated heterogeneity. Reparative M2 macrophages were enriched in Healing-DFUs (P=0.05), while inflammatory M1 macrophages displayed distinct transcriptome differences in Nonhealing-DFUs and Healing-DFUs. Cellular communication analysis revealed a pivotal role for HE-Fibro/Fibroblasts (signal-senders) and M1 (signal-receivers). HE-Fibro’s signaling significantly upregulated wound-resolving WNT, and ECM-remodeling CXCL pathways in Healing-DFUs, while M1 signaling upregulated healing-disruptive, and inflammation-associated, SPP1 pathways, in Nonhealing-DFUs. This study justifies using debrided tissues for single-cell assays and highlights the need for in-depth investigations into dysregulated wound healing microenvironments in AAs.
Project description:Diabetic foot ulcers (DFUs) are a devastating complication of diabetes. In order to identify systemic and local factors associated with DFU healing, we examined the cellular landscape of DFUs by single-cell RNA-seq analysis of foot and forearm skin specimens, as well as PBMC samples, from 10 non-diabetic subjects, and 17 diabetic patients, 11 with, and 6 without DFU. Our analysis shows enrichment of a unique inflammatory fibroblast population in DFU patients with healing wounds. The patients with healing DFUs also depicted enrichment of macrophages with M1 polarization, as opposed to more M2 macrophages in non-healing wounds. These findings were verified using Immunohistochemistry and Spatial Transcriptomics.