In a mouse meningitis model, the zmpC deletion mutant exhibited increased invasion of the brain and was associated with increased matrix metalloproteinase-9 in plasma and mortality as compared with the wild type.
Evidence is accumulating that gelatinase B (MMP-9) might be involved in the pathogenesis of meningitis, but the spectrum of different MMPs involved in the inflammatory reaction of this disease has not been determined.
The patients with encephalitis had the most significantly increased levels of MMPs in CSF, and MMP-3, MMP-8, and MMP-12 were exclusively increased in this group, whereas MMP-9 in CSF was increased in the patients with VZV meningitis.
The highest levels of MMP-9 were found in the CSF of patients with cryptococcosis, cytomegalovirus encephalitis and tuberculous meningitis and were comparable with those found in the CSF of HIV-negative patients with multiple sclerosis or meningitis.