Beyond 2D: effects of photobiomodulation in 3D tissue-like systems

Abstract

Significance: Currently, various scaffolds with immobilized cells are widely used in tissue engineering and regenerative medicine. However, the physiological activity and cell viability in such constructs might be impaired due to a lack of oxygen and nutrients. Photobiomodulation (PBM) is a promising method of preconditioning cells to increase their metabolic activity and to activate proliferation or differentiation. Aim: Investigation of the potential of PBM for stimulation of cell activities in hydrogels. Approach: Mesenchymal stromal cells (MSCs) isolated from human gingival mucosa were encapsulated in modified fibrin hydrogels with different thicknesses and concentrations. Constructs with cells were subjected to a single-time exposure to red (630 nm) and near-infrared (IR) (840 nm) low-intensity irradiation. After 3 days of cultivation, the viability and physiological activity of the cells were analyzed using confocal microscopy and a set of classical tests for cytotoxicity. Results: The cell viability in fibrin hydrogels depended both on the thickness of the hydrogels and the concentration of gel-forming proteins. The PBM was able to improve cell viability in hydrogels. The most pronounced effect was achieved with near-IR irradiation at the 840-nm wavelength. Conclusions: PBM using near-IR light can be applied for stimulation of MSCs metabolism and proliferation in hydrogel-based constructs with thicknesses up to 3 mm.

Application of Fibrin Associated with Photobiomodulation as a Promising Strategy to Improve Regeneration in Tissue Engineering: A Systematic Review

“…Three studies were used hydrogels or 3D fibrin [ 37 , 41 , 42 ], associated with PBM, being incorporated into the fibrin matrix endothelial cells [ 41 ], stromal vascular fraction (SVF) and mesenchymal stromal cells (MSCs) isolated from human gingival mucosa [ 37 ]. These studies agree that photobiomodulation combined with fibrin enhances the improvement of results, collaborating in cell and vascular proliferation.…”

Multicomponent Non-Woven Fibrous Mats with Balanced Processing and Functional Properties

“…Such phenotype variety can be caused by the altered mechanical properties of the substrate [ 45 , 46 ]. Moreover, it has been shown that cells need a proper surface patterning for alignment, while relatively soft porous substrates often cause a round cell morphology [ 47 , 48 ]. Therefore, PPCOG performed as an adhesive and porous biomesh, which makes it an excellent model for 3D cell growth.…”

Photobiomodulation in 3D tissue engineering

“…These semiconductor sources usually have a small area ( ) and LED/LD matrices or integrated optical components may be used to shape its radiation pattern. 100 – 102 LED and LD matrices are also more efficient for homogeneous irradiation of large areas, but, without special shapers, light intensity from laser devices often has a Gaussian shape with a maximum irradiance at the center and decreased irradiance on the periphery.…”

“… 161 Both red and NIR PBM stimulate metabolic activity and proliferation of gingival MSC encapsulated in a fibrin hydrogel. 101 It seems that PBM activates cell division in sufficiently soft scaffold systems, such as decellularized dermal matrices and hydrogels. 160 – 162 …”