Boyce S T, Supp A P, Harriger M D, Pickens W L, Wickett R R, Hoath S B
Shriners Burns Institute, Department of Surgery, University of Cincinnati, Ohio 45229, USA.
J Invest Dermatol. 1996 Jul;107(1):82-7. doi: 10.1111/1523-1747.ep12298286.
Restoration of an epidermal barrier is a definitive requirement for wound closure. To determine formation of an epidermal barrier as a function of hydration of the stratum corneum, we measured surface electrical capacitance (SEC) of the epidermis in cultured skin substitutes (CSS) in vitro and after grafting to athymic mice. CSS were prepared from human keratinocytes and fibroblasts attached to collagen-glycosaminoglycan substrates. On culture days 3, 7, 14, 17, and 21, SEC was measured in situ. CSS (n = 18; mean +/- SEM) showed a time-dependent decrease of SEC (picoFarads, "pF") from 4721 +/- 28 pF on day 3 to 394 +/- 117 pF on day 14, and subsequent increase to 1677 +/- 325 pF on day 21. After 14-d incubation, parallel CSS samples (n = 5) or murine autografts (n = 5) were grafted orthotopically to athymic mice. After grafting, CSS showed decreases in SEC from 910 +/- 315 pF at 2 wk to 40 +/- 10 pF at 4 wk with no significant decreases thereafter. Control values for murine autograft were 870 +/- 245 pF at 2 wk, and 87 +/- 30 pF at 4 wk. SEC values for native murine skin (n = 10) were 91 +/- 18 pF, and for native human skin (n = 10) were 32 +/- 5 pF. The data demonstrate that SEC decreases with time in culture and that healed or intact skin has approximately 10- to 100-fold lower SEC than CSS in vitro. This noninvasive technique provides a quantitative index of epidermal barrier in CSS in vitro and demonstrates the development of functional epidermal barrier during healing of wounds treated with cultured skin substitutes.
恢复表皮屏障是伤口愈合的决定性要求。为了确定作为角质层水合作用函数的表皮屏障形成情况，我们在体外培养的皮肤替代物（CSS）中以及移植到无胸腺小鼠后测量了表皮的表面电容（SEC）。CSS由附着在胶原-糖胺聚糖底物上的人角质形成细胞和成纤维细胞制备而成。在培养的第3、7、14、17和21天，原位测量SEC。CSS（n = 18；平均值±标准误）显示SEC（皮法，“pF”）随时间下降，从第3天的4721±28 pF降至第14天的394±117 pF，随后在第21天增加至1677±325 pF。经过14天的孵育后，将平行的CSS样本（n = 5）或小鼠自体移植物（n = 5）原位移植到无胸腺小鼠身上。移植后，CSS的SEC从2周时的910±315 pF降至4周时的40±10 pF，此后无显著下降。小鼠自体移植物的对照值在2周时为870±245 pF，在4周时为87±30 pF。天然小鼠皮肤（n = 10）的SEC值为91±18 pF，天然人皮肤（n = 10）的SEC值为32±5 pF。数据表明，SEC在培养过程中随时间下降，愈合或完整的皮肤的SEC比体外CSS低约10至100倍。这种非侵入性技术提供了体外CSS中表皮屏障的定量指标，并证明了在用培养的皮肤替代物治疗的伤口愈合过程中功能性表皮屏障的发展。
