Monoclonal antibody SZ168 targeting Podoplanin alleviates neuroinflammation by suppressing microglial Pyroptosis in cerebral Hemorrhage.

BACKGROUND

Neuroinflammation drives secondary brain injury after intracerebral hemorrhage (ICH). Podoplanin (PDPN), a transmembrane glycoprotein linked to inflammatory responses, is hypothesized to exacerbate neuroinflammation in ICH. We aimed to investigate whether targeting PDPN with the monoclonal antibody SZ168 mitigates neuroinflammation and brain injury via modulating microglial pyroptosis.

METHODS

A collagenase-induced ICH model was established in C57BL/6 mice, randomized into Sham, ICH + mIgG, and ICH + SZ168 (intraperitoneal injection at 6 h post-ICH, 5 mg/kg daily). Neurological deficits, cerebral edema, blood-brain barrier (BBB) permeability, and hemorrhage volume were assessed. In vitro, human microglial HMC3 cells were stimulated with hemin (100 μM) and treated with SZ168 (0-50 μg). Microglial invasion, migration, proliferation, and pyroptosis-related proteins (NLRP3, cleaved caspase-1, GSDMD-N) were analysed via Transwell, scratch, CCK-8, and Western blot.

RESULTS

SZ168 treatment improved neurological scores, reduced brain edema and hemorrhage volume, and preserved BBB integrity. In vitro, SZ168 dose-dependently suppressed microglial invasion, migration, and proliferation. Mechanistically, SZ168 downregulated NLRP3, cleaved caspase-1, and GSDMD-N, concomitant with reduced IL-1β and TNF-α levels.

CONCLUSIONS

Targeting PDPN with SZ168 alleviates neuroinflammation and secondary brain injury post-ICH by inhibiting microglial pyroptosis via the NLRP3/Caspase-1/GSDMD pathway. These findings nominate SZ168 as a potential therapeutic agent for ICH. These findings suggest that PDPN is a potential target for the treatment of ICH.