Provided herein are methods and compositions related to the use of human monocyte-derived microglia-like (MDMi) cells. In some embodiments, the methods and compositions provided herein relate to the use of MDMi cells to assess the effect of a clinical intervention on a human subject (e.g., a subject with a neurodegenerative disorder). In some embodiments, the methods and compositions provided herein relate to the use of MDMi cells to stratify human subjects into subgroup populations (e.g., populations that are likely to respond to a clinical intervention or are unlikely to respond to a clinical intervention). In some embodiments, the methods and compositions provided herein relate to the use of MDMi cells to identify candidate neurodegenerative disease biomarkers. In certain embodiments, the methods and compositions provided herein relate to the use of MDMi cells to screen potential therapeutic agents to identify candidate agents for the treatment of a neurodegenerative disease.