Inflammation‐Activated Endogenous Macrophage‐Mediated Prodrug Delivery System Overcoming Biological Barriers for Enhanced Oral Meningitis Therapy

Significant health risks are posed by meningitis due to its rapid progression, and challenges are encountered in intravenous antibiotic administration, especially in crossing the blood‐brain barrier. To address this, an inflammation‐activated, endogenous macrophage (MΦ)‐mediated oral prodrug delivery system is developed for targeted therapeutic interventions in bacterial meningitis treatment. This system is guided by inflammation‐derived chemoattractants and triggers drug release through inflammation‐induced reactive oxygen species (ROS). Comprised of naturally derived β‐glucans conjugated with the antibiotic cefotaxime (CTX) using a ROS‐responsive linker, nanoparticles (βGlus–CTX NPs) are formed in aqueous solutions. In a mouse model of Klebsiella pneumoniae‐induced meningitis, orally administered βGlus–CTX NPs are traversed by intestinal microfold cells, surpassing the intestine‐epithelial barrier, and are absorbed by resident endogenous MΦ. These MΦ‐mediated drug delivery vehicles are then traveled through the lymphatic and circulatory systems, crossing the compromised blood‐brain barrier, ultimately reaching inflamed brain tissues, guided by their derived chemoattractants. In ROS‐rich inflamed tissue environments, the linkers in the βGlus–CTX NPs are cleaved, releasing therapeutic CTX for localized treatment. Targeted antibiotic treatment for bacterial meningitis is offered by this oral, endogenous MΦ‐mediated prodrug delivery system, overcoming the robust gut‐to‐brain biological barriers and potentially enhancing effectiveness for comfortable home‐based treatment. Guided by chemoattractants released from inflamed tissues, the prodrug nanoparticles, transported by endogenous MΦ, traverse the lymphatic and circulatory systems, ultimately reaching the infected brain. This inflammation‐activated MΦ‐mediated delivery system not only overcomes substantial biological barriers between the gut and the brain but also responds to elevated ROS levels in inflamed tissues, triggering the release of the therapeutic drug.