Characterization of CD4+ Stem Cells of the Skin and Their Role in Skin Homeostasis and Tumorigenesis

This study focused on identifying and characterizing CD4+ non-haematopoietic, skin-resident cells and their role in skin homeostasis and tumorigenesis, particularly in basal cell carcinoma (BCC). The researchers used lineage-tracing, transcriptome sequencing, and flow cytometry to analyze potential CD4+ precursors in murine and human skin. They found that rare stem cell-like epidermal cells in the interfollicular epidermis (IFE) and infundibulum are likely candidates for BCC precursor cells. These CD4+ cells were shown to proliferate with age and wound healing in mice and possess similar stem cell-like characteristics in human skin. However, the exact origin of these cells remains uncertain due to limitations in investigative methods.