Analysis of immune responses in dogs with canine visceral leishmaniasis before, and after, drug treatment

The incidence of canine visceral leishmaniasis (CVL) is increasing in the M editerranean region. Many drugs have been tested for treatment of CVL, but little is known regarding their effect on test immune responses. in our stu dy, three dogs naturally infected with Leishmania infantum and five dogs ex perimentally infected with the same strain, were treated with dimethasulfon ate pentamidine (Lomidine) and the immune response evaluated before, and af ter, treatment. After the last injection, animals began to gain weight and the major clinical signs disappeared. Antibody titers gradually decreased t o low levels, six months after treatment. At the same time, antigen specifi c lymphoproliferation reappeared in the sampled animals. This study shows t hat, after treatment, immune cellular responses to leishmanial antigens, in volved in protection against Leishmania infection, were established. (C) 19 99 Elsevier Science B.V. All rights reserved.