Experimental granulomatous inflammation: II. Effect of injection of intact and disrupted killed tubercle bacilli into Freund adjuvant-sensitized Cavies.

The reaction of Freund adjuvant-immunized cavies to subsequent injection of Mycobacterium tuberculosis H37Ra is confirmed as an immunologically mediated phenomenon. Ultrasonic disruption of mycobacteria to be injected as "challenge" markedly increases the intensity of the consequent 24-48 h reaction and subsequent fibrosis in Freund adjuvant-sensitized cavies and has an apparently inhibiting effect on the extent of subsequent granuloma formation with marked reduction of the density of epithelioid cells. From this study, the 24-48 h reaction to injection of M. tuberculosis into sensitized animals appears clearly to be separable from subsequent granuloma formation depending upon the integrity or otherwise of the injected myocobacteria used as the challenge injection material.