Fieldsteel A H, Levy L
Int J Lepr Other Mycobact Dis. 1980 Sep;48(3):267-76.
Neonatally thymectomized Lewis rats (NTLR) were shown to be highly susceptible to infection with Mycobacterium leprae. We have used them in chemotherapeutic studies as models of human lepromatous leprosy. NTLR chronically infected with M. leprae were treated with various regimens combining a background of the minimal effective dose (MED) of dapsone (4,4'-diaminodiphenylsulfone, DDS) or 100 times this dose in the diet with one to ten doses of rifampin (RMP) of 10 mg/kg. To test for persisting viable M. leprae passage of 5 X 19(3) organisms was made to intact mice, and 10(5) to 10(7) acid-fast bacilli were passaged to NTLR. The only regimen that appeared to be completely effective in eliminating infectivity for intact mice was ten doses of RMP given on the background of the MED of DDS. No viable organisms were detected in any passage mice, but multiplication of M. leprae was detected in 12 of 16 passage NTLR, representing three of the four groups in which passage was made. In no instance did we fail to detect organisms in passage of NTLR when we detected them in passage mice, and multiplication was demonstrated in passage NTLR in 14 instances in which M. leprae failed to multiply in passage mice. Because of its high degree of immunosuppression, the NTLR was able to detect a small population of viable M. leprae in inocula containing up to 5000 times the number of organisms that can be inoculated into intact mice. The NTLR appears to provide a model for the study of microbial persistence in leprosy.
新生期胸腺切除的Lewis大鼠（NTLR）被证明对麻风分枝杆菌感染高度易感。我们已将它们用于化疗研究，作为人类瘤型麻风的模型。用各种方案治疗长期感染麻风分枝杆菌的NTLR，这些方案将氨苯砜（4,4'-二氨基二苯砜，DDS）的最小有效剂量（MED）或饮食中该剂量的100倍与1至10剂10 mg/kg的利福平（RMP）相结合。为了检测持续存活的麻风分枝杆菌，将5×19(3)个菌接种到未感染的小鼠体内，并将10(5)至10(7)个抗酸杆菌接种到NTLR体内。唯一似乎能完全消除对未感染小鼠传染性的方案是在DDS的MED基础上给予十剂RMP。在任何传代小鼠中均未检测到活的微生物，但在16只传代NTLR中的12只中检测到了麻风分枝杆菌的增殖，这12只代表了进行传代的四组中的三组。当我们在传代小鼠中检测到微生物时，在NTLR传代中从未未能检测到微生物，并且在14例传代小鼠中麻风分枝杆菌未增殖的情况下，在传代NTLR中证明了增殖。由于其高度的免疫抑制作用，NTLR能够在接种物中检测到一小部分存活的麻风分枝杆菌，该接种物中所含的菌数比可接种到未感染小鼠体内的菌数多5000倍。NTLR似乎为研究麻风病中微生物的持续存在提供了一个模型。
