IL6 and infection: Notably, both infection with the pneumolysin-deficient strain and treatment with VX765 were associated with attenuated brain inflammation, as reflected by lower CSF WBC counts and reduced CSF IL-1β and IL-6 levels, whereas cerebellar bacterial concentrations were slightly lower in mice infected with the pneumolysin-deficient strain but not in those treated with VX765 (Fig. 6).