Neurodegenerative diseases are debilitating conditions characterized by chronic inflammation, leading to dysfunction of both the non-neuronal cellular components of the central nervous system and peripheral blood immune cells. Thus, it is crucial to develop an innovative therapeutic strategy that not only effectively contrast neurodegeneration but also aims to reduce inflammation. The overall aim of the study is to provide a preclinical in vitro demonstration of the immunomodulatory and pro-regenerative potential of the human amniotic mesenchymal stromal cell (hAMSC) secretome in counteracting neurodegeneration. This potential will be evaluated in three-dimensional in vitro models of neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and chronic demyelinating disease (multiple sclerosis - MS). To this end, the study includes sample collection from patients without pharmacological treatment and without medical devices. Patients diagnosed with ALS, patients diagnosed with MS, and healthy volunteers will be recruited to collect blood samples and skin biopsies. Patient-specific and control organoid platforms, mimicking cellular heterogeneity and tridimensional interactions within the central nervous system including the inflammatory compartment, will be developed to be used as a valuable tool to investigate the in vitro efficacy of the hAMSC secretome.