A functional relationship between delayed hypersensitivity and antibacterial immunity.

The injection of living Listeria Monocytogenes into the site of a delayed hypersensitivity reaction in the footpads of mice resulted in inactivation of the organism. No such inactivation occurred when L. monocytogenes was injected into normal footpads. A correlation was observed between the magnitude of the delayed hypersensitivity reaction and the level of antibacterial resistance expressed within the delayed hypersensitivity site.