Therapy of murine cutaneous leishmaniasis by DNA vaccination

Prophylactic DNA vaccination protects mice against infection with Leishmani a major by inducing an exclusive Th1 immune response dominated by the produ ction of IFN-gamma. Here we show that DNA vaccines, initially designed to p revent infection, can also have a significant therapeutic effect. In L. maj or infected mice, vaccination with DNA encoding the Parasite Surface Antige n/gp46/M2 causes reduction in lesion size and promotes healing in both gene tically resistant C3H/He mice and susceptible BALB/c mice. The therapeutic effect is underpinned by a shift in the T cell-derived cytokine environment with an increase in the IFN-gamma producing Th1 type cells. Application of such immunotherapy in conjunction with antiparasite drugs may result in fa ster or more certain cure of the disease in humans. (C) 2000 Elsevier Scien ce Ltd. All rights reserved.