I am a Master’s student in Dr. Liisa Galea’s lab, focusing on the intersection of sex and APOE genotype in hippocampal plasticity and cognition during middle age, with a particular interest on the role of the complement system. Both sex and APOEε4 genotype are significant risk factors for Alzheimer’s Disease (AD). Notably, females with AD typically exhibit more severe neuropathological changes and cognitive decline compared to males. Additionally, female APOEε4 carriers face an elevated risk of earlier AD onset and more pronounced cognitive decline in middle age than their male counterparts. Therefore, understanding the influence of sex and genotype on cognition-related diseases is paramount. Intriguingly, studies have shown that inhibition of complement protein C3 can mitigate cognitive decline and restore neurogenesis levels. Thus, my research aims to investigate whether inhibiting complement protein C3 can rescue cognitive and neurogenesis deficits in APOEε4 carriers, with consideration for sex-specific effects.