Modulation of antibody response to sheep red blood cells by cyclophosphamide in Calomys callosus (Rodentia).
1. Calomys callosus, a wild rodent reservoir of Trypanosoma cruzi, notably resistant to laboratory infection with this parasite, is currently under study as a new experimental model for Chagas' disease. 2. To investigate the humoral immune response of C. callosus, rodents were injected with sheep red blood cells (SRBC) and the resulting antibody titers measured 0, 5, 9, 14, 20, 27 and 37 days later by the direct agglutination test. 3. Modulation of the antibody response by cyclophosphamide (Cy) was also studied, showing that the administration of 400 or 200 mg Cy/kg body weight one day prior to SRBC inoculation had an immunosuppressive effect. When the 200 mg/kg dose was given on day 0, antibody levels were significantly lower than those of controls on the 5th day after SRBC inoculation; subsequent differences were not statistically significant. 4. When SRBC were injected 5 or 10 days after Cy administration, the same effect was observed, indicating that the time of antigen inoculation is important in antibody modulation. A second dose of 200 mg Cy/kg on day 5 resulted in significant antibody suppression up to the 37th day. The administration of 20 mg Cy/kg resulted in a slight antibody enhancement seen on the 5th day after SRBC inoculation given on day 0. 5. These data demonstrate that cyclophosphamide modulates the T-dependent antibody response in C. callosus in a manner similar to the mouse model.
Borges
M M
MM
Instituto de Medicina Tropical de São Paulo, Brasil.
Kloetzel
J K
JK
Curi
P R
PR
D000372:Agglutination Tests; D000818:Animals; D000913:Antibodies, Protozoan / Q000032:analysis*; D000917:Antibody Formation / Q000187:drug effects; D003520:Cyclophosphamide / Q000494:pharmacology*; D004912:Erythrocytes / Q000276:immunology*; D005260:Female; D008297:Male; D012377:Rodentia / Q000469:parasitology*; D012756:Sheep; D014349:Trypanosoma cruzi / Q000276:immunology*
D000913:Antibodies, Protozoan; D003520:Cyclophosphamide