Transmissibility of sarcoid-specific granulomas in the footpads of mice.

Homogenate of 30 sarcoid lymph nodes was injected into the footpads of mice and 42% of the mice showed epitheloid-cell granulomas in the sites. However, the control lymph-node homogenates obtained from nonsarcoid patients also provoked similar granulomatous changes, although the positive rate was somewhat lower. In the granulomas a small amount of dust pigment remained, but no polarizing crystals were found in the sites or in the homogenate of either groups. No acid-fast bacilli, fungi, or other aerobic organisms were cultivated from the homogenate. Granuloma-formation activity remained after the homogenate had been sterilized in several ways and it existed in sediments of centrifugation of less than 2200 x g, but not in the supernate. The results seem to indicate that the granuloma formed in the footpads were the result of a local immunological reaction to the degenerated heterogenic protein of the injected and persistent homogenate.