Evaluation of Polymeric Particles for Modular Tissue Cultures in Developmental Engineering

Abstract

Developmental engineering (DE) aims to culture mammalian cells on corresponding modular scaffolds (scale: micron to millimeter), then assemble these into functional tissues imitating natural developmental biology processes. This research intended to investigate the influences of polymeric particles on modular tissue cultures. When poly(methyl methacrylate) (PMMA), poly(lactic acid) (PLA) and polystyrene (PS) particles (diameter: 5–100 µm) were fabricated and submerged in culture medium in tissue culture plastics (TCPs) for modular tissue cultures, the majority of adjacent PMMA, some PLA but no PS particles aggregated. Human dermal fibroblasts (HDFs) could be directly seeded onto large (diameter: 30–100 µm) PMMA particles, but not small (diameter: 5–20 µm) PMMA, nor all the PLA and PS particles. During tissue cultures, HDFs migrated from the TCPs surfaces onto all the particles, while the clustered PMMA or PLA particles were colonized by HDFs into modular tissues with varying sizes. Further comparisons revealed that HDFs utilized the same cell bridging and stacking strategies to colonize single or clustered polymeric particles, and the finely controlled open pores, corners and gaps on 3D-printed PLA discs. These observed cell–scaffold interactions, which were then used to evaluate the adaptation of microcarrier-based cell expansion technologies for modular tissue manufacturing in DE.

Integrated Experimental and Mathematical Exploration of Modular Tissue Cultures for Developmental Engineering

“…After sterilization with 70% ethanol overnight and rinsing three times with phosphate-buffered saline (PBS, Lonza, Walkersville, MD, USA), the particles were submerged in 1 mL of DMEM medium. Some spherical MSs aggregated in DMEM, as observed in previous studies [ 71 ]. Aliquots of 1 mL of HDFs (10 3 cells/mL) were seeded into each well and cultured at 37 °C in a 5% CO 2 humidified atmosphere for different time periods.…”

“…To construct 3D functional tissues through the bottom-up DE strategy, it is essential to culture multiple mammalian cells on individual or aggregated MSs with varying sizes and structures [ 70 , 71 ]. For comparative analysis, simulations were also conducted for hepatocytes colonized within the VE using the validated oxygen diffusion model.…”

“…Samples of 5 mg spherical PMMA particles with a diameter of 30–100 µm were prepared following a previously reported method [ 71 ] by dissolving PMMA in dichloromethane and injecting 8 mL of 5 mg/mL organic solution into 150 mL of 5% poly(vinyl alcohol) under magnetic stirring for 2.5 h. These particles were then added to each well of 24-well TCPs. After sterilization with 70% ethanol overnight and rinsing three times with phosphate-buffered saline (PBS, Lonza, Walkersville, MD, USA), the particles were submerged in 1 mL of DMEM medium.…”

“…PLA discs with a diameter of 6 mm and a thickness of 500 µm were fabricated using 3D printing, incorporating circular open pores (diameters: 400, 500, 640, and 1100 µm), corners (angles: 30, 60, 90, and 120°), and gaps (distances: 100, 200, 300, 400, and 500 µm), following a previously described method [ 71 ]. Briefly, the nozzle temperature of 210 °C for 3D-printing was selected, the print bed temperature was 60 °C, the printing speed was 1000 mm/min, and the set extrusion width and the layer height were 0.4 and 0.167 mm respectively.…”

The effect of human PBMCs immobilization on their Аβ42 aggregates-dependent proinflammatory state on a cellular model of Alzheimer’s disease

“…Thirdly, such a cultivation process is static, it does not occur in the flow of the nutrient medium and leads to the formation of gradients of influencing factors and metabolites, which complicates the standardization of studies (Vanoni et al, 2022). These shortcomings can be solved by using the GEM (Global Eukaryotic Microcarrier) technology, which allows not only immobilization and cultivation of cells on the surface of transparent spherical microcarriers made of alginate but also constant maintenance of cells in suspension, which brings the cultivation conditions markedly closer to in vivo conditions (Tavassoli et al, 2018;Xiang et al, 2023). In view of the above, the aim of the presented work was to compare the intensity of the response of cells in suspension and immobilized cells as part of GEM microcarriers to the exogenous Aβ42 stimulus.…”