Diabetic foot ulcers debridement SCRNA-seq showed healing association with inflammatory fibroblasts in minorities

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. DFU debrided samples were collected from patients with Healing- and Nonhealing DFUs and transported to lab from clinic on ice. Tissue was dissociated into single cells using standardized method and frozen viably. Viably thawed cells were used for preparing single cell RNA sequencing libraries using 3'v3.1 10x genomics kits. The libraries were then sequenced using Novaseq S4 and NextSeq 500 platforms. >>>Raw data for human samples not available due to patient privacy concerns<<<