Humoral and Cellular Immune Responses in Dogs With Inapparent Natural Leishmania Infantum Infection

Vet J. 2011 Nov;190(2):e43-e47. doi: 10.1016/j.tvjl.2011.04.005. Epub 2011 May 18.


Molecular analysis, serology and immunophenotyping for T lymphocytes and their subsets, B lymphocytes and monocytes were performed on dogs naturally infected with Leishmania infantum. Animals were categorised as asymptomatic dogs I (AD-I), with negative serology and positive molecular results, and asymptomatic dogs II (AD-II), with positive serology and positive molecular results, and these were compared to symptomatic dogs (SD) and control dogs (CD). AD-I exhibited immunophenotypic features similar to those of CD, including isotype profiles and concentrations of monocytes. Similar biomarkers were found in AD-II and SD, such as, higher levels of immunoglobulins IgG, IgG2, IgM and IgA and higher concentrations of eosinophils. High frequencies of T lymphocytes and CD4(+) T cells were observed in both AD-I and AD-II compared to SD, whereas CD8(+) T cells were higher only in AD-II compared with SD. Analysis of B lymphocytes revealed an increased frequency of this cell type only in AD-II animals compared with SD. Asymptomatic dogs appear to have a dichotomous infection spectrum that can influence the humoral and cellular immunological status during canine visceral leishmaniasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / blood
  • Asymptomatic Infections*
  • B-Lymphocytes / metabolism
  • Biomarkers / blood
  • CD4-CD8 Ratio / veterinary
  • Case-Control Studies
  • Disease Resistance
  • Dog Diseases / immunology*
  • Dog Diseases / parasitology
  • Dogs
  • Enzyme-Linked Immunosorbent Assay / veterinary
  • Eosinophils / metabolism
  • Flow Cytometry / veterinary
  • Immunity, Cellular*
  • Immunity, Humoral*
  • Immunoglobulins / blood
  • Leishmania infantum / immunology*
  • Leishmaniasis, Visceral / immunology
  • Leishmaniasis, Visceral / veterinary*
  • Monocytes / metabolism
  • T-Lymphocyte Subsets / metabolism
  • T-Lymphocytes / metabolism


  • Antibodies, Protozoan
  • Biomarkers
  • Immunoglobulins