University of Kentucky Researchers Discover Immune Fingerprint in Blood That Predicts Severe Alzheimer’s Drug Side Effects

University of Kentucky researchers find an immune "fingerprint" in blood that predicts brain swelling and bleeds caused by new Alzheimer’s treatments.

By: AXL Media

Published: Mar 10, 2026, 12:27 PM EDT

Identifying the Biological Obstacles to Alzheimer’s Immunotherapy

The recent FDA approval of lecanemab marked a historic milestone in slowing Alzheimer’s disease, yet the treatment carries a significant risk of amyloid-related imaging abnormalities (ARIA). These side effects, which manifest as brain swelling or micro-bleeds on MRI scans, currently serve as a major deterrent for many families and clinicians. However, researchers at the University of Kentucky have uncovered a breakthrough immune "fingerprint" that distinguishes which patients are biologically predisposed to these complications, moving the field from reactive monitoring toward proactive prevention.

The Discovery of a Revved Up Immune Signature

Using advanced genetic and metabolic profiling, a team led by Josh Morganti, Ph.D., analyzed blood samples from patients undergoing lecanemab treatment at the Norton Neuroscience Institute. The research revealed that patients who developed ARIA possessed a specific subset of T cells that were metabolically accelerated and "poised for action." This coordinated immune response suggests that ARIA is not a random occurrence but a measurable biological event that can be detected through a standard blood draw rather than invasive brain biopsies.

Moving Beyond Genetic Risk Factors with Precision Medicine

Prior to this study, the primary known risk factor for ARIA was the presence of the APOE ε4 gene variant. While this genetic marker indicated higher risk, it offered little insight into the actual biological mechanisms at play. The University of Kentucky’s findings provide the first in-depth look at the peripheral immune system's role in these side effects. By identifying T cells that express the molecular machinery necessary to interact with the vascular system, researchers have established a concrete biological signature that can be monitored in real-time during the course of treatment.