(1296-A) Gene-Edited Induced Pluripotent Stem Cell-Derived Microglia as a Platform for Neurodegenerative Research
Monday, February 5, 2024
12:00 PM – 1:00 PM EST
Location: Exhibit Halls AB
Abstract: Human microglia are essential immune cells that help regulate the homeostatic microenvironment of the central nervous system by surveying and aiding in the cleanup of their surroundings. In Alzheimer’s Disease (AD), patients show increased presence of amyloid plaques around neurons which is thought to be exasperated by microglia dysfunction. Genetic risk factors for AD include the APOE4 allele and abnormal TREM2 function, but restricted availability of primary cells and tissue limit the ability to run comprehensive studies to better understand these genetic impacts. Herein, we propose the use of CRISPR-edited human induced pluripotent stem cell (iPSC) lines to produce large-scale homogenous populations of microglia to model AD-associated phenotypes. Briefly, we differentiated APOE-TREM2-edited (KO and R47H) iPSC lines and wild-type (WT) iPSC lines into hematopoietic progenitors and then further specified into a microglia fate. Next, we characterized TREM2-KO and TREM2-R47H “disease-like” microglia via imaging, flow cytometry, and western blotting. We observed APOE-TREM2 modified microglia are less adherent with shorter ramified morphologies, compared to WT microglia, and have lower expression of homeostatic surface markers such as P2RY12, CX3CR1 and TMEM119. They also have signs of impairment in motility and phagocytosis when exposed to a fluorochrome conjugated β-amyloid (Aβ) peptide (1-42) as compared to WT microglia. These results suggest gene-modified iPSC-derived microglia can provide a scalable source of cells for neurodegenerative disease modeling, which could be translated to other genetic-related diseases and other iPSC-derived cell types.