SUSCEPTIBILITY OF SEVERE COMBINED IMMUNODEFICIENT MICE TO MYCOBACTERIUM-LEPRAE

The susceptibility of severe combined immunodeficient (SCID) mice to h uman leprosy bacilli was investigated. Nude mice were used as controls . SCID mice were found to be highly susceptible to Mycobacterium lepra e and the progress of infection was comparatively 2-3 months earlier t han observed in the nude mice. After reaching a maximum of similar to 1 x 10(9) acid fast bacilli/foot pad at about 8 months postinfection t he number of bacilli gradually decreased. The progress of infection in nude mice was different from that found in SCID mice. The multiplicat ion of M. leprae in the foot pads of nude mice continued and reached s imilar to 2.0 x 10(10) bacilli/foot pad and then nearly remained the s ame. The results indicate that SCID mice can be used as a suitable mod el for screening antileprosy drugs while nude mice should be involved in the production of M. leprae for use in other fields of leprosy rese arch.