抄録
A long-term observation, up to 80 weeks, was carried out on the development of experimental mouse leprosy, concerning the relation between the clinical features of leproma at the site of inoculation and the evolution of visceral lesions.
Four mouse strains, C3H, C57BL/6, ddY and CF# 1, were used for this experi-ment. Mice of these 4 strains were inoculated subcutaneously with 0.25cc of a 1:1000 suspension prepared from subcutaneous leproma (the Hawaiian strain). The development of lepromata at the inoculation site was observed by palpation at intervals of 5 weeks until 80 weeks after inoculation and evaluated by their clinical features. And then 3 mice of each strain were sacrificed 20, 40, 60 and 80 weeks after inculation to examine the extent of visceral lesions.
In strain C3H, the typical malignant course of the disease was followed throughout the observation period. The experimental animals died within 50 weeks, with extensive involvement of visceral organs.
In the mice of C57BL/6 strain, leproma at the inoculation site showed the benign type, and the late stage of infection, generally remained small with a tendency to regress. But 4 of 10 mice inoculated were extremely emaciated at the end of experi-ment and died in 55 to 80 weeks after inoculation, showing severe visceral lesions. In contrast, the visceral organs, except the lungs, of 2 mice sacrificed at 60 weeks revealed the presence of slight lesions.
The disease course of ddY strain was similar to that of C57BL/6 strain. It should be remarked that the lungs of ddY mice, sacrificed at 80 weeks, showed severe involvement, whereas lesions of the other organs were still slight.
In the CF#1 mice inoculated, all but one showed the benign type leproma at the inoculation site. Thereafter 3 of them were sacrificed at 40 weeks. Their lepromata were of the benign type, but the visceral lesions were severe, being comparable to those of the advanced case of C3H strain. The remaining 5 died within 45 to 55 weeks, with severe visceral lesions as observed in the malignant cases. The one exceptional case showed the typical malignant course and died in 35 weeks. From these results, subcutaneous infection with murine leprosy in CF# 1 mice was found to give a disparity in the relation between the feature of leproma at the inoculation site and the involve-ment of visceral organs.
