マウス足蹠内へのらい菌接種

Abstract

Four strains of mouse-passage M. leprae provided by Shepard were inoculated into the left hind foot-pads of CF#1 mice. The number of bacteria inoculated per foot-pad ranged from 7.89×102 to 2.37×103, 8.6 to 20.6% of which were stained solidly. The mice were housed in an animal room at 20±1°C, and fed the usual pelleted commercial chow. Three to four mice from a group of mice which were inoculated with a strain were sacrificed about 6 and 9 months after inoculation, and the inoculated foot-pads were dissected off and pooled for each harvest. The number of acid-fast bacteria was counted, the ratio of solidly staining bacteria determined and the generation time calculated.It was conclusively demonstrated that M. leprae could be transmitted to the mouse foot-pad. Multiplication of M. leprae was consistent but limited so that it reached a maximum logarithmic phase by about 6 months after inoculation, which was followed by a plateau phase. The calculated generation time from inoculation to a maximum logarithmic phase ranged from 18.2 to 23.6 days. The ratio of solidly staining bacteria rose during this period and declined later. The acid-fast bacteria from inoculum and harvest were inoculated to Ogawa's medium and incubated at 33° and 37°C for 3 months. No cultivable mycobacteria were isolated. Subcutaneous inoculation of the bacteria to mice failed to produce any lesions.