Short report: Dynamic changes of hepatocyte growth factor in eosinophilic meningitis caused by angiostrongylus cantonensis infection

Hepatocyte growth factor (HGF) is a member of the angiogenic growth factor family, which exerts a variety of effects on epithelial, endothelial, and neuronal cells by binding to the c-MET receptor tyrosine kinase. It was reported that HGF attenuates cerebral ischemia-induced increase in permeability of the blood-brain barrier (BBB) and decreases in expression of tight junction proteins in cerebral vessels of rats. Studies on the localization of the c-Met/HGF receptor in the rat brain and the interaction with HGF after brain injuries show that HGF plays an important role as a neurotrophic factor in the brain. To assess the role of HGF in patients with eosinophilic meningitis, a retrospective, cohort study was conducted to measure the dynamic changes of HGF in the cerebrospinal fluid (CSF) and blood of nine patients with eosinophilic meningitis. The mean HGF_CSF at presentation, 1 week, 2 weeks, and 3 weeks after admission was 539 pg/mL, 540 pg/mL, 376 pg/mL, and 279 pg/mL, respectively. The mean level of HGF_CSF at presentation (539 ± 242 pg/mL) and 1 week after admission (540 ± 213 pg/mL) was significantly higher than in controls (162 ± 207 pg/mL)(P = 0.02 and P = 0.01, respectively). The CSF/blood ratio of HGF at presentation (0.61) was higher when compared with physiologic situations in uninfected individuals (0.51). The levels of HGF in CSF were not correlated with the amount of CSF cells or proteins. All patients recovered without neurologic sequelae. These results indicate that high concentrations of HGF in the CSF occur in eosinophilic meningitis, and may have a role in protecting against endothelial injury and reducing BBB dysfunction.