Caspr1 is a host receptor for meningitis-causing Escherichia coli

Area of Science:

• Neuroscience
• Microbiology
• Immunology

Background:

• Escherichia coli is a primary cause of Gram-negative bacterial meningitis in neonates.
• The precise mechanisms of E. coli meningitis pathogenesis, particularly blood-brain barrier (BBB) penetration, are not fully understood.

Purpose of the Study:

• To identify host factors involved in E. coli's invasion of the central nervous system.
• To elucidate the role of the Caspr1 protein in E. coli meningitis.

Main Methods:

• Identification of host receptors for E. coli virulence factors.
• Genetic manipulation of Caspr1 expression in endothelial cells.
• In vivo rodent models of meningitis.
• Analysis of signaling pathways activated by bacterial-host interactions.

Main Results:

• Caspr1 was identified as a host receptor for the E. coli virulence factor IbeA.
• Genetic deletion of Caspr1 in endothelial cells and blocking IbeA-Caspr1 interaction inhibited E. coli BBB penetration.
• IbeA-Caspr1 interaction activates focal adhesion kinase signaling, promoting bacterial entry into brain endothelial cells.
• E. coli invasion of hippocampal neurons, leading to apoptosis, was dependent on the IbeA-Caspr1 interaction.

Conclusions:

• E. coli utilizes the host receptor Caspr1 to penetrate the blood-brain barrier, leading to meningitis.
• Caspr1 represents a potential therapeutic target for preventing or treating E. coli meningitis.