RESUMO
The continued failure to grow the leprosy bacillus in vitro and the limited and localized nature of the infection resulting from the inoculation of Mycobacterium leprae into normal mice emphasise the need for an experimental animal which readily permits growth of the bacillus.
Assuntos
Camundongos , Animais , Camundongos Nus/microbiologia , Hanseníase/fisiopatologia , Modelos Animais de DoençasRESUMO
Continuous dietary administration of rifampin to mice with an established Mycobacterium leprae footpad infection reduced the bacillary solid ratio, with an estimated survival half-life of 5-6 days. In rifampin-treated immunosuppressed animals the survival half-life of solid bacilli, in the absence of host immunity, was 12-13 days. Clofazimine and B1912 produced a significant effect on solid ratio only after a lag period of apparently 100 days. The rate of action was considerably slower than that of rifampin. Intermittent (once monthly) administration of both drugs produced effects similar to those of continuous administration.
Assuntos
Animais , Camundongos , Anticorpos Antibacterianos , Clofazimina/análogos & derivados , Clofazimina/farmacologia , Clofazimina/uso terapêutico , Fatores de Tempo , Hanseníase/imunologia , Hanseníase/tratamento farmacológico , Terapia de Imunossupressão , Mycobacterium leprae , Mycobacterium leprae/imunologia , Rifampina/farmacologia , Rifampina/uso terapêuticoRESUMO
A technique is described for the intratesticular inoculation in mice and rats of suspensions of M. leprae murium, and for subsequent quantitative assessment of bacterial multiplication by counting the numbers of stained bacilli in homogenates of testes from animals killed at inervals. The method is convenient to carry out, and a statistical assessment shows that considerable accuracy is attainable. Bacilli from an 18-month-old rat leproma, transferred to a different host species, the mouse, showed a "lag" phase of 2-5 weeks in its multiplication, succeeded by a logarithmic phase which ciontinued for a further 2-3 months. On the other hand, when rat testes were inoculated with bacilli from a 7-month-old rat-testis leproma, the logarithmic phase was entered at once. The mean generation time in this phase was 7-8 days in rats, and 10 days in mice. During the "lag" phase a transient but significant increase in average bacillus length occurred. Suramin treatment of mice enhanced the growth of the bacilli in them. In rats, however, its effect was to decrease the rate of multiplication.