{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T08:47:14Z","timestamp":1782895634376,"version":"3.54.5"},"reference-count":22,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T00:00:00Z","timestamp":1782864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Diabetic foot ulcers (DFUs) are devastating diabetic complications characterized by an extremely high non-healing rate and elevated risk of life-threatening outcomes. To characterize the cellular landscape and macrophage-associated alterations between DFU tissue and diabetic non-ulcer foot (DNFU) skin, we performed a comprehensive reanalysis of publicly available single-cell RNA sequencing (scRNA-seq) datasets.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A fully reproducible R-based analytical pipeline was used to process public scRNA-seq count matrices (GSE165816) from 5 DFU and 8 DNFU skin samples. A total of 27,844 cells (16,579 from DFU and 11,265 from DNFU skin) passed stringent quality control filters. Data normalization, integration, dimensionality reduction, unsupervised clustering, and marker-based cell type annotation were performed using the Seurat and Harmony packages. Sample-level comparisons included cell fraction analysis and UCell pathway scoring. Macrophages were further investigated through subclustering analysis, edgeR-based pseudobulk differential expression analysis, volcano plot visualization, GO over-representation analysis, enrichment analysis, and CellChat ligand-receptor interaction inference.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The integrated single-cell atlas resolved 10 major cell compartments including epithelial, stromal, endothelial, lymphatic endothelial, smooth muscle\/pericyte, lymphoid, myeloid, mast cell, plasma cell, and melanocyte\/Schwann cells. Sample-level cell fraction analysis revealed a nominal reduction in lymphatic endothelial cells in DFU; however, no cell type proportion differences remained statistically significant after false discovery rate (FDR) correction. Similarly, no significant differences were observed in macrophage UCell pathway scores for glycolysis, lactate metabolism, combined glycolysis-lactate metabolism, TNF-NF-\u03baB signaling, or insulin\/IGF signaling between DFU and DNFU skin following FDR correction. Macrophage subclustering identified DFU-enriched subpopulations, and macrophage pseudobulk analysis prioritized multiple DFU-associated genes. Notably, sex-linked genes including XIST, RPS4Y1, and DDX3Y reached statistical significance after FDR correction, indicating that a portion of the observed transcriptional signal may be attributed to demographic imbalance between groups. Exploratory enrichment analysis of nominal and ranked macrophage differentially expressed genes highlighted DFU-directional enrichment of translation, oxidative phosphorylation, electron transport, and antigen presentation terms, while DNFU-directional genes were enriched for\u00a0transcriptional regulation and rhythmic process terms. CellChat analysis\u00a0prioritized macrophage-associated CD99-CD99 and MIF-CD74\/CXCR4 ligand-receptor pairs as key DFU-associated intercellular communication hypotheses.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This single-cell reanalysis comparing DFU and DNFU skin identifies putative ligand-receptor interaction hypotheses, transcriptomic alterations, and macrophage subpopulation shifts that require definitive validation in larger, clinically well-characterized, and spatially resolved patient cohorts.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1875481","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T08:12:54Z","timestamp":1782893574000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Single-cell reanalysis identifies macrophage-associated transcriptional and intercellular communication features in diabetic foot ulcers"],"prefix":"10.3389","volume":"16","author":[{"given":"Jia","family":"Yao","sequence":"first","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]},{"name":"The Affiliated Dongguan Songshan Lake Central Hospital, Guangdong Medical University","place":["Dongguan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang-qing","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xue-jian","family":"Deng","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiong-biao","family":"Yu","sequence":"additional","affiliation":[{"name":"The First Affiliated Hospital of Guangdong Pharmaceutical University","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tuo-pu","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wan-mei","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Guangzhou Twelfth People\u2019s Hospital","place":["Guangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3390\/molecules26164917","article-title":"Skin wound healing: Normal macrophage function and macrophage dysfunction in diabetic wounds","volume":"26","author":"Aitcheson","year":"2021","journal-title":"Molecules (Basel Switzerland)"},{"key":"B2","doi-asserted-by":"publisher","first-page":"1838","DOI":"10.1111\/iwj.13789","article-title":"A multicenter clinical trial evaluating the durability of diabetic foot ulcer healing in ulcers treated with topical oxygen and standard of care versus standard of care alone 1\u2009year post healing","volume":"19","author":"Al-Jalodi","year":"2022","journal-title":"Int. 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