MARCKS and GSDMD pathway genes co-expression drives blood-brain barrier disruption in tuberculous meningitis

Tuberculous meningitis (TBM), the most severe form of Mycobacterium tuberculosis infection, carries high mortality and neurological sequelae, primarily due to blood-brain barrier (BBB) disruption. While GSDMD-mediated endothelial pyroptosis is recognized as a key inflammatory mechanism, the broader molecular landscape driving BBB damage in TBM remains incompletely understood. Identifying central mediators beyond GSDMD is crucial for developing adjunctive barrier-stabilizing therapies.

Researchers employed an integrated multi-omics approach, combining bulk and single-cell RNA sequencing (RNA-seq) from both clinical patient datasets and murine TBM models. This was followed by experimental validation to pinpoint key mediators of BBB dysfunction. The study focused on identifying genes significantly upregulated in TBM, with subsequent single-cell analysis to localize expression and functional enrichment to understand their mechanistic roles. Protein levels of MARCKS were also assessed in patient peripheral blood mononuclear cells (PBMCs).

The study identified and validated three genes—MARCKS, CD274 (PD-L1), and IL17RA—as significantly upregulated in tuberculous meningitis (TBM). Single-cell analysis of a murine TBM model demonstrated predominant MARCKS expression within CNS microglia, a finding supported by elevated MARCKS protein levels in peripheral blood mononuclear cells from TBM patients. Functional enrichment and correlation analyses positioned MARCKS at the nexus of inflammatory signaling and cytoskeletal regulation. It showed strong associations with key effectors of the GSDMD pyroptosis pathway, including CASP4, CD14, and NINJ1.