Effects of negative pressures on epithelial tight junctions and migration in wound healing

Abstract

Negative-pressure wound therapy has recently gained popularity in chronic wound care. This study attempted to explore effects of different negative pressures on epithelial migration in the wound-healing process. The electric cell-substrate impedance sensing (ECIS) technique was used to create a 5 x 10(-4) cm(2) wound in the Madin-Darby canine kidney (MDCK) and human keratinocyte (HaCaT) cells. The wounded cells were cultured in a negative pressure incubator at ambient pressure (AP) and negative pressures of 75 mmHg (NP(75)), 125 mmHg (NP(125)), and 175 mmHg (NP(175)). The effective time (ET), complete wound healing time (T(max)), healing rate (R(heal)), cell diameter, and wound area over time at different pressures were evaluated. Traditional wound-healing assays were prepared for fluorescent staining of cells viability, cell junction proteins, including ZO-1 and E-cadherin, and actins. Amount of cell junction proteins at AP and NP(125) was also quantified. In MDCK cells, the ET (1.25 +/- 0.27 h), T(max) (1.76 +/- 0.32 h), and R(heal) (2.94 +/- 0.62 x 10(-4) cm(2)/h) at NP(125) were significantly (P < 0.01) different from those at three other pressure conditions. In HaCaT cells, the T(max) (7.34 +/- 0.29 h) and R(heal) (6.82 +/- 0.26 x 10(-5) cm(2)/h) at NP(125) were significantly (P < 0.01) different from those at NP(75). Prominent cell migration features were identified in cells at the specific negative pressure. Cell migration activities at different pressures can be documented with the real-time wound-healing measurement system. Negative pressure of 125 mmHg can help disassemble the cell junction to enhance epithelial migration and subsequently result in quick wound closure.

Effect of Negative Pressure on Proliferation, Virulence Factor Secretion, Biofilm Formation, and Virulence-Regulated Gene Expression ofPseudomonas aeruginosaIn Vitro

“…In this study, the negative pressure value (−125 mmHg) was consistent with the clinical use of negative pressure in NPWT, and the O 2 tension was kept at 20% during bacterial culture in order to reduce interference from low oxygenation [29]. Colony diameter and growth curve indicated that negative pressure conditions could significantly inhibit the proliferation and growth rate of P. aeruginosa.…”

The effects of negative pressure treatment on the extracellular matrix gene expression and protein production of fibroblasts

“…Negative pressure (subatmospheric pressure) culture system A custom cell culture system with controllable air pressure was fabricated (NPI1000, Linston Advanced Technology, Longtan, Taoyuan, Taiwan) [22]. Air in the chamber was removed by a vacuum pump with a speed of 46 l/min and the rate of pressure drop of 12.5 mmHg/s.…”

Cell Cycle Dependent Association of EBP50 with Protein Phosphatase 2A in Endothelial Cells

“…To study wound healing/cell migration ECIS (Electric cell-substrate impedance sensing) model Zθ, Applied BioPhysics Inc. (Troy, NY) was used that applies high electric field to make a well defined injury in a confluent cell monolayer and to screen the repopulation of this wounded area by noninvasive measurements [20], [39]. Wild type, mock, or mutant EBP50 transfected cells were seeded on type 8W10E arrays.…”