Effects of cyclosporin A on bacterial growth and immunological responsiveness in BALB/c mice infected with Mycobacterium leprae.
When BALB/c mice were infected with Mycobacterium leprae and orally treated 6 times weekly with a dose of 8 mg/kg cyclosporin A (CsA) for 19 months, the number of organisms was slightly higher at 19 months as compared with mice in which the dose of CsA was gradually decreased after 6 months and discontinued at the 8th month (p less than 0.01 for the 15th and 19th months). Lymphocyte blast transformation (LBT) showed that spleen cells from CsA-treated mice 4 weeks after infection with M. leprae and 3 weeks after CsA treatment was stopped responded to the sonicated supernatant of M. leprae suspension (SS), M. leprae (Ml), and concanavalin A (ConA) less than those cells from mice not treated with CsA. This response was dose-dependent. At week 15, 14 weeks after CsA administration was stopped, the LBT response to SS and Ml by cells from M. leprae-infected mice exceeded that of mice without CsA treatment, and the response to ConA in M. leprae-infected mice was less than that in uninfected mice without CsA-treatment. Thus, if CsA was administered, the T-cell functions were suppressed. However, when CsA treatment was discontinued for longer periods, the T-cell function was activated. From these results, we speculate that M. leprae would have the capability of growing more abundantly in mice treated with CsA 100 mg/kg for 1 week every month.
Tanaka
M
M
Department of Bacteriology, Faculty of Medicine, Tottori University, Japan.
Tanaka
Y
Y
Kohsaka
K
K
D000818:Animals; D016572:Cyclosporine / Q000494:pharmacology*; D005260:Female; D006968:Hypersensitivity, Delayed; D007111:Immunity, Cellular / Q000187:drug effects; D007918:Leprosy / Q000276:immunology* / Q000382:microbiology; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D009166:Mycobacterium leprae / Q000187:drug effects* / Q000254:growth & development; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology
D016572:Cyclosporine