Table II

Cure of Leishmaniasis after GK1.5-based Immunotherapy Is Associated with Unipolar Th1-type Cytokine Responses

GroupAntigen-induced cytokine levels
IFN-γIL-4*
ng/ml ± SEM
Experiment 1
 Control (n = 5)1.42 ± 0.191.24 ± 0.35
 Immunotherapy (n = 5)0.88 ± 0.390.06 ± 0.02
Experiment 2
 Uninfected0.11≤0.05
 Control (n = 5)1.36 ± 0.07‡1.28 ± 0.17
 Immunotherapy (n = 3)1.01 ± 0.12‡0.05
 Nonhealing (n = 2)§2.081.53
  • BALB/c mice were treated with GK1.5 and 11B11 mAb, followed by intralesional rIL-12 as described in the text. Lymph node cells were harvested after disease recovery at wk 4 of reinfection (Experiment 1) or at wk 7 after immunotherapy (Experiment 2) and were cultured for 48 h in the presence of 10 μg/ml of soluble leishmania antigen. Cytokine concentrations were measured by specific ELISA. Control lymph node cells were from BALB/c mice infected for 4 wk with L. major.  

  • *  IL-4 was measured in antigen-stimulated cultures to which anti–IL-4 receptor mAb had been added (10 μg/ml). IL-4 levels in all cultures were reduced by >96% in the presence of anti–MHC II mAb.  

  •  Antigen-stimulated IFN-γ production was reduced 60.8 ± 5.4% for control mice and 46.3 ± 7.5% for immunotherapy mice after neutralization of MHC II by anti–I-Ed/I-Ad mAb added at 10 μg/ml to antigen-stimulated cultures.  

  • § Two mice failed therapy, as indicated by chronic footpad swelling and cutaneous ulceration.