Author ORCID Identifier(s)

https://orcid.org/0000-0002-3245-0028

Date of Award

5-2026

Document Type

Thesis

Degree Name

Doctor of Philosophy (PhD)

First Advisor

Betty Diamond, MD

Abstract

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease in which up to 95% of patients develop neuropsychiatric manifestations (NPSLE), including mood and anxiety disorders for which the underlying mechanisms remain poorly understood. A subset of antidouble-stranded DNA antibodies (DNRAbs) present in approximately 30% of patients with SLE cross-react with the GluN2A and GluN2B subunits of the N-methyl-D-aspartate receptor (NMDAR) and have been implicated in central nervous system (CNS) pathology contingent on blood-brain barrier (BBB) breach. While DNRAb-mediated hippocampal injury following lipopolysaccharide-induced BBB opening has been characterized, the persistent consequences of DNRAb exposure in areas of the brain relevant to the anxiety and mood disorders prevalent in NPSLE had not been defined. This dissertation characterizes the chronic phase of DNRAb mediated amygdala injury using an integrated approach comprising in vivo positron emission tomography (PET) with [..C]AIB tracer, behavioral testing, immunohistochemistry, multielectrode array (MEA) electrophysiology, and single-cell RNA sequencing (scRNA-seq). Female B6H2d mice were immunized with DWEYS peptide multimerized on a polylysine backbone to generate DNRAbs (DNRAb+) or with polylysine backbone alone as controls (DNRAb−). Systemic epinephrine administration was used to induce amygdala-selective BBB permeability. Behavioral testing included the object place memory (OPM) task, elevated plus maze (EPM), and elevated zero maze (EZM). [..C]AIB PET imaging confirmed that epinephrine induces a spatially restricted BBB breach localized exclusively to the amygdala, permitting DNRAb penetration selectively into the lateral (LAD) and basolateral (BLA) amygdala nuclei. DNRAb+ mice demonstrated significant reduction in NeuN immunoreactivity in the LAD and BLA with intact dendritic arborization and no detectable evidence of ongoing apoptosis, indicating a chronic or slowly evolving injury state. A reduced proportion of active spiking units on MEA recording confirmed functional circuit impairment. DNRAb+ mice exhibited loss of 4 normal anxiety-related behavior on both the EPM and EZM without impairment of hippocampus dependent spatial memory, establishing amygdala circuit specificity. All histologic and behavioral phenotypes were absent in Grin2a knockout mice, identifying GluN2A-containing NMDARs as obligate mediators. PET imaging performed months after epinephrine administration revealed persistent BBB permeability which was exacerbated in DNRAb+ compared to DNRAb- mice. scRNA-seq of 166,331 amygdala cells identified a convergent transcriptional stress signature across glutamatergic neurons, microglia, endothelial cells, and pericytes, characterized by suppression of the circadian clock negative feedback limb, immediate-early gene hypoactivity, upregulation of neurodegenerative stress-response programs, and loss of endothelial quiescence. Microglial transcriptomics revealed a shift from a homeostatic to an activated state with disinhibition of NF-κB-mediated inflammatory signaling. These findings establish that amygdala-specific DNRAb exposure produces a self-sustaining, GluN2A-dependent chronic injury state mechanistically distinct from previously characterized hippocampal pathology, with functional, behavioral, and transcriptomic correlates that parallel the anxiety and mood disorders prevalent in NPSLE. These results identify GluN2A-NMDAR engagement, persistent BBB disruption, and post-excitotoxicity neurodegenerative stress across the neurovascular unit as potential therapeutic targets for the psychiatric burden of NPSLE.

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