Abstract: Objective · To explore the characteristics of diabetic foot ulceration (DFU)-related genes expression and immune cells. Methods · Gene expression data set GSE80178 was downloaded from the GEO database. Six DFU samples and three diabetic foot skin (DFS) samples were used to identify the differentially expressed genes (DEGs). The biological processes and cellular components of the DEGs were annotated by using Gene Ontology (GO). The relative proportions of immune cells among DFU samples, DFS samples and non-diabetic foot skin (nDFS) samples were calculated and compared by the deconvolution method. Results · A total of 296 DEGs were obtained, including 80 genes up-regulated and 216 genes down-regulated. GO analysis found that the DEGs were enriched in the cellular components such as exosomes and extracellular space, and in the biological processes such as keratinocyte differentiation, keratinization, and neutrophil chemotaxis. The comparison between DFS and nDFS showed no difference in immune cell proportions, while compared with DFS, the proportions of activated mast cells, resting natural killer cells, CD8+ T cells and monocytes increased in the DFU samples. Conclusion · In the pathogenesis of DFU, there may be active keratinization and immunoregulation in the lesion, and the infiltration of activated mast cells, resting natural killer cells, CD8+ T cells and monocytes may increase in the lesion. Hyperglycemia itself may have little effect on the relative number of immune cells in local skin.

Key words: diabetic foot ulceration (DFU), diabetic foot skin (DFS), differentially expressed gene (DEG), immune cell, bioinformatics