Keratinocyte and Fibroblast Wound Healing In Vitro Is Repressed by Non-Optimal Conditions but the Reparative Potential Can Be Improved by Water-Filtered Infrared A

Abstract

It is a general goal to improve wound healing, especially of chronic wounds. As light therapy has gained increasing attention, the positive influence on healing progression of water-filtered infrared A (wIRA), a special form of thermal radiation, has been investigated and compared to the detrimental effects of UV-B irradiation on wound closure in vitro. Models of keratinocyte and fibroblast scratches help to elucidate effects on epithelial and dermal healing. This study further used the simulation of non-optimal settings such as S. aureus infection, chronic inflammation, and anti-inflammatory conditions to determine how these affect scratch wound progression and whether wIRA treatment can improve healing. Gene expression analysis for cytokines (IL1A, IL6, CXCL8), growth (TGFB1, PDGFC) and transcription factors (NFKB1, TP53), heat shock proteins (HSP90AA1, HSPA1A, HSPD1), keratinocyte desmogleins (DSG1, DSG3), and fibroblast collagen (COL1A1, COL3A1) was performed. Keratinocyte and fibroblast wound healing under non-optimal conditions was found to be distinctly reduced in vitro. wIRA treatment could counteract the inflammatory response in infected keratinocytes as well as under chronic inflammatory conditions by decreasing pro-inflammatory cytokine gene expression and improve wound healing. In contrast, in the anti-inflammatory setting, wIRA radiation could re-initiate the acute inflammatory response necessary after injury to stimulate the regenerative processes and advance scratch closure.

Treatment with a red‐laser‐based wound therapy device exerts positive effects in models of delayed keratinocyte and fibroblast wound healing

“…19,20 It could recently be shown that wIRA radiation improved scratch healing under nonoptimal conditions in vitro. 25 In contrast, UV-B irradiation under the same conditions resulted in severe damage to keratinocytes as well as fibroblasts and wound healing was impeded. 25 Other light therapy devices might employ red light lasers (600-760 nm) at low intensity, e.g., 'low level laser light therapy' (LLLT), or light emitting diodes in the range of violet to green (380-495 nm), e.g., 'blue light phototherapy' and 'photodynamic therapy" (PDT).…”

“…25 In contrast, UV-B irradiation under the same conditions resulted in severe damage to keratinocytes as well as fibroblasts and wound healing was impeded. 25 Other light therapy devices might employ red light lasers (600-760 nm) at low intensity, e.g., 'low level laser light therapy' (LLLT), or light emitting diodes in the range of violet to green (380-495 nm), e.g., 'blue light phototherapy' and 'photodynamic therapy" (PDT). Recently, positive effects of a novel, red-laser-based wound therapy device (WTD) on stimulation of cell regeneration and wound healing of connective tissue cells were reported.…”

Effects of Histamine and the α-Tocopherol Metabolite α-13′-COOH in an Atopic Dermatitis Full-Thickness Skin Model

“…Human HaCaT cells (kindly provided by Prof. Norbert Fuesing, Heidelberg, Germany) and human primary keratinocytes (generated from juvenil phimosis; 4739-03/16) were cultured in 175 cm 2 cell culture flasks (Greiner bio-one, Frickenhausen, Germany) as previously described [ 68 ].…”

“…RNA purification, reverse transcription and real-time polymerase chain reaction were carried out as previously described [ 68 ]. Relative gene expression was calculated using the 2-ΔΔ Ct method using β-actin as a housekeeping gene for normalization [ 72 ].…”

Replacement in angiogenesis research: Studying mechanisms of blood vessel development by animal-free in vitro, in vivo and in silico approaches

“…Meanwhile, several companies offer systems for the fully automated, high-throughput performance and analysis of wound scratch assays during large-scale screens ( Nowak-Sliwinska et al, 2018 ). This indicates that this type of assay is well-established and broadly used, not only to investigate the migratory activity of endothelial cells, but also of various other benign and malignant cell types ( Ideta et al, 2021 ; Wiegand et al, 2021 ; Fong et al, 2022 ).…”