3D Artificial Skin Model As a Novel Strategy for the Detection of Pyroptosis-Cascade Activation in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a severe adult-onset neurodegenerative disease with limited treatment approaches. Evidence has shown that degeneration of cutaneous nerves may reflect neurodegenerative processes occurring within the central nervous system. Although skin biopsy is widely adopted in clinical practice, the procedure is invasive and requires multiple patients' tissue removals. Therefore, we developed a 3D innervated skin model by combining 3D printing of methacrylated hyaluronic acid as an innovative tool for better reproducing the dermis and epidermis and electrospinning of polylactic acid for mimicking skin innervation. Later, 3D artificial skin was colonized with a preneuronal cell line (SH-SY5Y) and fibroblasts isolated from skin biopsy of ALS patients at different disease stages. 3D skin possesses a porosity suitable for cell colonization and a high stability. Importantly, biological results reveal an increase of TAR DNA-binding protein 43 aggregates, NOD-like receptor pyrin domain containing protein 3, interleukin (IL)-18, IL-6, and nitrites in 3D skin of ALS patients, thus indicating pyroptosis activation linked to neurodegeneration. This physiologically relevant 3D skin model reduces the need for repeated biopsies, allows standardized experimental conditions, and supports biomarker research and preclinical drug testing in ALS.