Abstract
C3H/He strain mice, approximately 5 weeks of age, were subcutaneously inoculated at the thorax with 0.25ml of a 1: 1000 saline suspension prepared from a malignant leproma in a C3H mouse infected with murine leprosy bacilli, strain Hawaiian, about 25 weeks earlier. The susceptibility of these mice to the bacilli was evaluated by the development of leproma at the infection site and also by the involvement of visceral organs.
In only 2 out of 10 male mice tested, typically malignant leproma was observed at the infection site throughout the observation period. In almost all the other mice, subcutaneous leproma showed benign-like features at the early stage of infection. The leproma increased in size gradually, but did not show typically malignant features even at 40 to 50 weeks. However, visceral lesions in all the mice seemed to be severe with time, since autopsy revealed extensive involvement of the viscera. The visceral lesions and mean survival time of C3H/He mice were similar to those obtained in C3H mice. There were no pronounced differences in the susceptibility between male and female groups.
The susceptibility of C3H and C57BL/6 strain mice was also examined by the same manner above mentioned, as controls. Mice of C3H and C57BL/6 strains showed typically malignant and benign features, respectively.
From the observations of this and of our earlier experiments, it is clear that the disease course in C3H/He mice was intermediate to that observed in C3H and CF # 1 mice.
