Intestinal infections establish antigen-specific, long-lived memory CD4(+) T cells in the brain and meninges.

Gastrointestinal infections induce long-lasting, antigen-specific memory CD4(+) T cells in the brain and meninges, with up to 80% of dural T cells being gut-derived.

• Why it matters: Understanding how the immune system links gut infections to brain immunity is crucial for addressing neuroinflammatory and neuroinfectious diseases. This work fills a gap by revealing the migration and persistence of gut-primed T cells in the CNS borders.
• What they did: The study used gastrointestinal challenges with bacteria and parasites, tracking CXCR6-CXCL16-dependent migration of gut-activated CD4+ T cells to the dura mater, where they formed durable memory populations and responded rapidly upon re-exposure.
• The result: This discovery demonstrates that intestinal infections can establish durable, antigen-specific immune memory in the CNS borders, potentially influencing responses to bloodborne pathogens and neuroinflammation.