[On the lesions caused by a leproma-derived and cultivated Mycobacterium HI-75 produced in ddY mice. With special reference to a factor influencing the lesions and the differences from those by BCG].

Not only in the experimental leprosy, primary aim to make every experimental model crucial for the medical research has been the simulation of the aspect of disease encountered in human case by the simplest possible way. The present study was conducted to do so making some variations in addition to the experimental lepromata, produced in nude mice by Sasaki et al. and by Hamit, utilizing a leproma-derived and cultivated Mycobacterium HI-75 (HI-75). In this study HI-75, Mycobacterium bovip BCG (BCG) and female SPF ddY(ddY) were utilized to make experimental models. In addition to these combinations, the effect of the immunization of beta-glucuronidase binding protein (BGBP) to the lesion was also examined. The BGBP extracted from pisum sativum and utilized in this study shows cross-immunoreactivity with those of HI-75 and M. leprae. As the results, the lesions caused by HI-75 and BCG were somewhat resembling though HI-75 caused a little more extensive lesions especially in lymphocytic and monocytic infiltration. Also HI-75 caused distinct nerve lesions(NL) in which the bacilli were often encountered in the endoneurium but not in those by BCG. Contrarily in mice immunized with BGBP, the lesions were only a little milder and the affected tissue was a little fibrosed. However, in NL the solid form HI-75 were more often observed in the endoneurium. The results indicated that the effect of BGBP immunization on the HI-75 induced lesion was not very clear by the present study alone, however, the proposed models itself should be and will become very useful, for experimental leprology with only slight modifications.