Integration of Flow Cytometry and Computational Analysis to Dissect the Epidermal Cellular Subsets in Keloids that Correlate with Recurrence

Keloid disease is a benign skin disease that does not have an effective therapy. More and more research shows that epidermal abnormalities are involved in keloid pathogenesis. Little is known about the relationship between the abnormal epidermal immunophenotype and clinical outcome. Nine-color flow cytometry with computational analysis was performed to detect the altered cellular subpopulation distribution in keloid lesions. Receiver operating characteristic curves were drawn to compare predictive ability between the alteration of cell subgroup frequency and the Vancouver Scar Scale. The frequency of CD49fhi/CD29 +/-/TLR7 +/- cellular subsets increased in the keloid epidermis compared with that in the healthy control. CD49fmid-hi/CD29 +/-/TLR7 +/-/ CD24 +/- cellular subpopulation level was increased significantly in keloids, whereas CD49flo-mid/CD29-/TLR7-/ CD24- cellular subpopulation frequency was decreased. The CD49flo/CD29-/TLR7-/CD24 +/-/CD117 +/- cellular subpopulation showed an increased frequency during recurrence with a sensitivity of 66.7% and specificity of 91.7%. The area under the curve was 0.806 for cellular subpopulation analysis, which was higher than the area under the curve for the Vancouver Scar Scale (0.583). The alteration of keloid epidermal subpopulation frequency is related to recurrence, which will provide an optional predictive marker for keloid recurrence and a potential target subset for investigating the generation of keloid.