Systemic Tuberculin Sensitivity in Mice

Summary Fatal tuberculin shock was observed regularly in C57Bl/6Ks mice sensitized with live bacillus Calmette-Guérin (BCG) and challenged 3 weeks later with purified protein derivative (PPD). Specific desensitization with PPD was also achieved. The symptoms of tuberculin shock in the mouse which is typically delayed, are closed eyes, ruffled fur, lessened activity, irregular breathing, hypothermia and unconciousness. Mice of different inbred strains varied greatly in their susceptibility to active tuberculin shock, mice of the C57Bl/6Ks, NZB, and S/W strains being highly susceptible, mice of the A/Jax and NZW strains being moderately resistant, and mice of the T6 strain being highly resistant. Systemic tuberculin sensitivity was induced in C57Bl/6Ks mice with heat-killed as well as with live BCG. The interperitoneal route for sensitization was highly effective and the severity of tuberculin shock varied directly with both the sensitizing dose of BCG and the challenge dose of PPD. Sensitivity reached a peak 2 to 3 weeks after injection of BCG. The intraperitoneal and intravenous routes were found to be highly effective routes for challenge.