Figure 5.

Validation of the ΔSPINK5 Model for Therapeutic Intervention In Vivo

Skin grafts were produced with healthy donor keratinocytes (HK Ctrl), immortalized ΔSPINK5 clone (HKΔSPINK5+E6E7), and SPINK5-transduced immortalized ΔSPINK5 clone (HKΔSPINK5+E6E7+SPINK5). (A) Histological analysis (H&E staining) of grafts produced with HKΔSPINK5+E6E7+SPINK5 shows the recovery of a normal epidermal architecture with marked reduction of rete ridges. (B) Human-specific involucrin immunostaining (hINV) confirms the human origin of the grafts. Insets depict the staining at the mouse-human skin border. (C) Restored expression of LEKTI closely follows the pattern of involucrin in the SPINK5 corrected grafts, verifying SPINK5 expression recovery. (D–F) Immunoperoxidase detection of (D) keratin K10 and (E) psoriasin, along with (F) in situ zymography, reveals that the skin equivalents regenerated from the SPINK5-transduced immortalized ΔSPINK5 keratinocytes fairly resemble those of healthy donor keratinocytes, with normal expression recovery of molecular markers and reduced proteolytic activity. Scale bars, (A–E) 100 μm, (F) 50 μm.