Bio-Interfaces Engineering Using Laser-Based Methods for Controlled Regulation of Mesenchymal Stem Cell Response In Vitro

Abstract

The controlled interfacial properties of materials and modulated behaviours of cells and biomolecules on their surface are the requirements in the development of a new generation of high-performance biomaterials for regenerative medicine applications. Roughness, chemistry and mechanics of biomaterials are all sensed by cells. Organization of the environment at the nano-and the microscale, as well as chemical signals, triggers specific responses with further impact on cell fate. Particularly, human mesenchymal stem cells (hMSCs) hold a great promise in both basic developmental biology studies and regenerative medicine, as progenitors of bone cells. Their fate can be affected by various key regulatory factors (e.g. soluble growth factors, intrinsic, extrinsic environmental factors) that can be delivered by a fabricated scaffold. For example, when cultured on engineered environments that reproduce the physical features of the bone, hMSCs express tissue-specific transcription factors and consequently undergo an osteogenic fate. Therefore, producing smart bio-interfaces with targeted functionalities represents the key point in effective use of hierarchically topographical and chemical bioplatforms. In this chapter, we review laser-based approaches (e.g. Matrix-Assisted Pulsed Laser Evaporation (MAPLE), Laser-Induced Forward Transfer (LIFT), laser texturing and laser direct writing) used for the design of bio-interfaces aimed at controlling stem cell behaviour in vitro.

Bioinstructive Micro-Nanotextured Zirconia Ceramic Interfaces for Guiding and Stimulating an Osteogenic Response In Vitro

“…A significant change from stiff edges to curved ones was created by a 10% crossover of the laser beam on the irradiation area, an attenuation of the abrupt profile characteristic to grooves and ridges being obtained, thus providing a surface curvature for cell surface interaction. Table S1, taken from the profilometry measurements, the roughness depending on both profile and 3D areas increased significantly after the laser texturing process, but no significant differences were observed between the measured roughness within the sidewalls of the structures or at the bottom of the structures, not resembling the previously ripple-like structures observed in circular patterns by Dinca et al [35] and Stamatiuc et al [39].…”

“…The type of tissue formed at this interface Femtosecond (fs) laser surface modification is used as a debris-or contaminant-free technique that can confer automatized, reproducible, fast time processed surfaces with increased roughness and stable characteristics. Due to low thermal loading and the ability to maintain the bulk properties of the material after fs laser processing, the disadvantages of other previously described surface modification techniques could be overcome [33], and high-quality microstructures and machining precision could be obtained as an exciting alternative to those obtained by conventional surface treatments of Zirconia surfaces [34][35][36][37][38][39][40].…”

“…There are few studies related to the interaction of MSCs with micro-nanotopographies generated in Zirconia-based materials, treating mainly pit-like or ditch-like topographies. Our previous results, for example, show that droplet-shaped microcavity arrays lead to an increased surface area inducing cell morphology modification toward a polygonal shape and, consequently, increases the circularity of the stem cell nuclei [ 35 ]. The cytoskeleton filaments extend jointly over their combined granular and ripple-like structures present within each cavity [ 35 ].…”

Induced Hydrophilicity and In Vitro Preliminary Osteoblast Response of Polyvinylidene Fluoride (PVDF) Coatings Obtained via MAPLE Deposition and Subsequent Thermal Treatment

“…For these materials, the major challenge of surface engineering is the introduction of reactive groups to the surface [25], the lack of control in the deposited area homogeneity, tailoring the final thickness, expense, and the process being time-consuming. In recent decades, laser techniques, especially Matrix-Assisted Pulsed Laser Evaporation (MAPLE) [28][29][30][31], have proved to be viable methods for organic material processing in tissue engineering applications [32][33][34]. This technique offers unique advantages compared to conventional deposition methods of soft materials-for example, the spin coating technique [8,22].…”

“…The MAPLE method "gently" allows the material of interest to be transferred to the substrate with little or no damage to its structure, chemical properties, and functionality; the matrix responsible for the dilution and homogenization of the material of interest absorbs the wavelength of the laser beam, is evaporated, and is then pumped out of the deposition chamber [29][30][31]. Other advantages of this technique are the low consumption of materials, the control over thickness (by monitoring the deposition rate), control over surface roughness (by changing the target characteristics and number of pulses), and uniform transfer on non-planar substrates, as well the deposition of composite or multilayer films/coatings [33][34][35][36][37]. MAPLE allows the transfer of a wide range of materials, being thus successfully used for transferring different types of organic materials and polymers, such as the chemoselective polymers [38], nanoparticles [39], electro-conductive polymers [40,41], biodegradable polymers [42], thermoresponsive polymers [43], and even active proteins [44,45], as well as layers of organic materials with graded composition [39], liquid crystals [46,47], and much other more [44,48,49].…”