Bacterial meningitis: The role of transforming growth factor-beta in innate immunity and secondary brain damage

Project 6 of the NCCR `Neural Plasticity and Repair' focuses on
mechanisms of immunity and tissue damage in autoimmune and
infectious diseases of the central nervous system (CNS). In one of
the subprojects, the influence of transforming growth factor-P
(TGF-P) on the immune reactivity of the CNS was investigated. In
mice with Streptococcus pneumoni ae-induced meningitis, a deletion
of TGF-P receptor 11 on leukocytes is found to enhance recruitment
of neutrophils to the site of infection and to promote bacterial
clearance. The improved host defense against S. pneumoniae was
associated with an almost complete prevention of meningitis-induced
vasculitis, a major intracranial complication leading to brain
damage. The data show that endogenous TGF-beta suppresses host
defense against bacterial infection in the CNS. This contrasts with
findings from other body compartments that suggested that TGF-beta
is a powerful chemotactic cytokine and increases microbial
clearance. Copyright (C) 2007 S. Karger AG, Basel