Longitudinal analysis of cytokine gene expression and parasite load in PBMC in Leishmania infantum experimentally infected dogs

Vet Immunol Immunopathol. 2008 Sep 15;125(1-2):168-75. doi: 10.1016/j.vetimm.2008.04.010. Epub 2008 Apr 20.


Canine visceral leishmaniasis (CVL) is caused by Leishmania infantum, an intracellular protozoan parasite that causes a severe infectious disease. To evaluate the gene expression profile associated to CVL in vivo, we have measured monthly by real-time PCR over one year the IL-4, IL-10, IL-12, IL-13, IFN-gamma, TGF-beta and TNF-alpha mRNA levels in peripheral blood mononuclear cells in 6 experimentally infected dogs that exhibited different progressions of the illness. While in two dogs no parasite, or a very low number of parasites, was detected and the two dogs did not show any clinico-pathological abnormalities at the end of the study (L dogs), for the remaining dogs high parasite loads were detected and they developed clinical leishmaniasis (H dogs). The L dogs have null expression of both IL-4 and IL-13 for the first 4 months after the infection, whereas an early IL-4 and IL-13 expression occurs in this period of infection in most of the dogs that developed clinical leishmaniasis (H dogs). Furthermore, a higher IFN-gamma expression was associated with the increase of parasite load and clinical status in these dogs. Moreover, the high variability of expression at the pre-infection stage causes us to reject the possibility that the basal levels of these cytokines indicate the prognosis of the subsequent response against infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Protozoan / blood
  • Cytokines / biosynthesis*
  • Cytokines / genetics
  • Dog Diseases / blood
  • Dog Diseases / genetics
  • Dog Diseases / immunology
  • Dog Diseases / parasitology*
  • Dogs
  • Gene Expression
  • Gene Expression Profiling
  • Leishmania infantum / growth & development*
  • Leishmaniasis, Visceral / blood
  • Leishmaniasis, Visceral / genetics
  • Leishmaniasis, Visceral / immunology
  • Leishmaniasis, Visceral / veterinary*
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / parasitology*
  • Longitudinal Studies
  • RNA / chemistry
  • RNA / genetics
  • Reverse Transcriptase Polymerase Chain Reaction / veterinary
  • Statistics, Nonparametric


  • Antigens, Protozoan
  • Cytokines
  • RNA