Fig. 3

Spatial patterns in the optical redox ratio of the epithelial tongue indicate a sensitivity to proliferation. a Keratinocytes in the epithelial tongue of unstained wound sections, distinct from dermal collagen SHG and granulation tissue, produced a low optical redox ratio (scale bar = 250 µm). b A redox ratio gradient was observed in the epithelial tongue at the wound edge (scale bar = 100 µm). c Keratinocytes at the base of the tongue, proximal to the dermis, had lower redox ratio values than the keratinocytes at the tip toward the wound center. Ki67 immunostaining revealed a high density of proliferative keratinocytes at the base of the epithelial tongue corresponding to regions with a lower redox ratio (scale bar = 100 µm). d The tip of the epithelial tongue, displaying a higher redox ratio, contained no signs of proliferation