Identification of Shared Genes and Immune Profiling for Pathological Scar

Pathological scar (PS), encompassing hypertrophic scars (HS) and keloids, significantly impacts skin morphology and functions. Evidence suggests both exhibit hyperactive immune-inflammatory responses, yet research remains limited. This study used bioinformatics to explore shared genes and immune response characteristics in PS. Transcriptomic datasets (GSE181540 and GSE158395) were explored to investigate differentially expressed genes (DEGs) between normal skin and HS/ keloids using the "limma" package. Overlapping up- and downregulated genes were visualized via a Venn diagram and subjected to GO and KEGG enrichment to highlight immune-related processes, particularly in chemotaxis, indicating immune response abnormalities in both scar types. Differentially expressed immune-associated genes (DEIGs) were identified by overlapping DEGs with immune-associated genes. Seventy-eight DEIGs were mapped to protein-protein interaction (PPI) networks, revealing VCAM1, THBS1, and SERPINE1 as the key hub genes. Immunohistochemical staining showed these genes were highly expressed in keloid and HS tissues but expressed at lower levels in normal skin. Ultimately, immune cell infiltration analysis unveiled increased immune cell proportions in HS and keloids, with keloid tissue displaying higher immune cell abundance.