Design and execute the proposed experiment to test the hypothesis: 'TREM2-Mediated Astrocyte-Microglia Cross-Talk in Neurodegeneration'. Primary outcome: Reduction of astrocyte A1 markers (C3, Lcn2 mRNA) >=40% vs 5xFAD-vehicle; NOR discrimination index >=0.65. Estimated cost: $85,000; timeline: 18 months.