Decoding NMDAR encephalitis: proteomic markers and computational identification of potential therapeutic pathways

Area of Science:

• Neuroimmunology
• Proteomics
• Genetic Epidemiology

Background:

• The proteome offers potential therapeutic targets for neurological disorders.
• Anti-N-Methyl-D-Aspartate Receptor Encephalitis (NMDAR-E) is a debilitating autoimmune condition.
• Identifying specific protein markers is crucial for NMDAR-E diagnosis and treatment.

Purpose of the Study:

• To conduct a proteome-wide Mendelian randomization (MR) study.
• To identify potential protein biomarkers and therapeutic targets for NMDAR-E.
• To validate candidate proteins through experimental models.

Main Methods:

• Utilized protein quantitative trait loci (pQTLs) from GWAS data for 734 plasma proteins.
• Performed a large meta-analysis of NMDAR-E cases (323) and controls (1,519).
• Validated findings using microglial cell stimulation, a mouse model, and assessed druggability.

Main Results:

• Genetically predicted levels of 37 proteins associated with NMDAR-E risk.
• Elevated SIRPA, LGALS3, CASP3 and decreased TREM2, IL1RN correlated with increased NMDAR-E risk.
• Identified proteins expressed in B cells, mast cells, and monocytes; validated in microglial cells and mouse models.

Conclusions:

• Successfully identified protein biomarkers associated with NMDAR-E risk through integrated genetic and functional studies.
• MR-predicted causal proteins align with antibody-driven expression changes, confirming pathological relevance.
• Provides actionable insights for NMDAR-E biomarker screening and therapeutic development.