Immunohistochemical distribution of Ki67 in epidermis of thick glabrous skin of human digits

Abstract

The glabrous skin on the flexor sides of hands and feet, compared to other integument regions, has thicker epidermis and more complex pattern of epidermal ridges, wherefore in microscopy is denominated as thick skin. The epidermis of this skin type has individually unique and permanent superficial patterns, called dermatoglyphics, which are maintained by regenerative potential of deep epidermal rete ridges, that interdigitate with adjacent dermis. Using light microscopy, we analyzed cadaveric big toes thick skin samples, described histology of deep epidermal ridges (intermediate, limiting, and transverse), and quantitatively evidenced their pattern of proliferation by immunohistochemical assessment of Ki67. Immunohistochemical distribution of Ki67 was confined to basal and suprabasal layers, with pattern of distribution specific for intermediate, limiting and transverse ridges that gradually transform within epidermal height. Deep epidermal ridges, interdigitating with dermal papillae, participate in construction of intricate epidermal base, whose possible role in epidermal regeneration was also discussed. Having a prominent morphology, this type of epidermis offers the best morphological insight in complexities of skin organization, and its understanding could challenge and improve currently accepted models of epidermal organization.

A 3D In Vitro Model for Burn Wounds: Monitoring of Regeneration on the Epidermal Level

“…The positive signal for Ki67 was restricted to the basal layer of our model, which was expected, since transiently amplifying keratinocytes in the basal layer of the epidermis are responsible for tissue renewal [ 35 , 36 ]. Although a weak Ki67 signal was also found in the burned areas, this was probably attributed to the presence of denaturized Ki67 protein.…”

Boot camp: Training and dressing regimens for modeling plantar wounds in the swine

“…As has been previously described, 8,16 human plantar skin exhibits distinctive structural characteristics primarily in the epidermis, which is substantially thickened due to both increased number of cell layers and enlargement of keratinocytes and corneocytes, with prominent rete ridges interdigitating deeply with the underlying dermis (Figure 4(a)). Porcine plantar skin is thicker overall, and lacks friction ridges (an evolutionary adaptation to arboreal habitats that is found only in primates and koalas), but otherwise shares many similarities with its human counterpart, including thickening of both the viable and cornified epidermis, pronounced rete ridges, and a compact stratum corneum composed of densely packed, enlarged corneocytes (Figure 4(b)).…”