ABSTRACT
BACKGROUND: Negative-pressure of 125 mmHg (NP) has been shown to accelerate wound healing. Effects of NP on human keratinocyte behaviors during wound healing process were highlighted in this study. METHODS: An NP incubator incorporating the electric cell-substrate impedance sensing (ECIS) technique has been built to quantify monolayer keratinocytes movement in serum-free media at the ambient pressure (AP) and NP for 12 h. Monolayer cell motions were continuously recorded by ECIS in the frequency range of 22.5-64 kHz. Membrane capacitance (Cm), cell-substratum resistance (α), and cell-cell junction resistance (Rb) were evaluated in cells at the different pressures. RESULTS: A greater monolayer cell migration distance was found in cells at NP. Decreased cell-substratum adhesion reflected in the significantly low α (AP:NP = â¼5 Ω(0.5):â¼3 Ω(0.5)â cm), decreased integrin expression, and increased cell-substratum distance were seen in cells at NP. A significantly increased Cm (AP:NP = â¼4:â¼8 µF/cm(2)) in association with increased membrane ruffling and microtubule filaments were observed early in the monolayer cell movement at NP. A progressive drop in the Rb from 1.2 Ω·cm(2) to 0.8 Ω·cm(2) corresponding to the gradually decreased E-cadherin expressions were observed 6 h after wound closure after NP treatment. CONCLUSION: A quick membrane ruffling formation, an early cell-substratum separation, and an ensuing decrease in the cellular interaction occur in cells at NP. These specific monolayer cell behaviors at NP have been quantified and possibly accelerate wound healing.
