Enhancement Of Intracerebral Infection Of Mice With Bordetella Pertussis

SUMMARY Intracerebral infection of mice with low-virulence strains of Bordetella pertussis was greatly enhanced by the prior administration of cortisone acetate subcutaneously or of vitamin-A alcohol or streptolysin O intracerebrally. The infections did not appear to stimulate the release of lysosomal enzymes in the brain. When normal mice were X-irradiated to the head, with the body shielded, subsequent intracerebral infection with low-virulence strains was very much enhanced. Irradiation of the head alone did not affect the survival of actively immunised mice after the intracerebral injection of either high-virulence or low-virulence strains, but irradiation of the body, with the head shielded, significantly reduced the number of survivors after infection with a high-virulence strain. It appears that a cerebral glial response controls intracerebral infections with low-virulence strains in normal mice, but that circulating leucocytes play a major role in controlling infections with high-virulence strains in immunised mice.