Intramuscular immunization with p36(LACK) DNA vaccine induces IFN-gamma production but does not protect BALB/c mice against Leishmania chagasi intravenous challenge

Parasitol Res. 2005 Dec;98(1):67-74. doi: 10.1007/s00436-005-0008-8. Epub 2005 Nov 1.

Abstract

Acute visceral leishmaniasis is a progressive disease caused by Leishmania chagasi in South America. The acquisition of immunity following infection suggests that vaccination is a feasible approach to protect against this disease. Since Leishmania homologue of receptors for activated C kinase (LACK) antigen is of particular interest as a vaccine candidate because of the prominent role it plays in the pathogenesis of experimental Leishmania major infection, we evaluated the potential of a p36(LACK) DNA vaccine in protecting BALB/c mice challenged with L. chagasi. In this study, mice received intramuscular (i.m.) or subcutaneous (s.c.) doses of LACK DNA vaccine. We evaluated the production of vaccine-induced cytokines and whether this immunization was able to reduce parasite load in liver and spleen. We detected a significant production of interferon gamma by splenocytes from i.m. vaccinated mice in response to L. chagasi antigen and to rLACK protein. However, we did not observe a reduction in parasite load neither in liver nor in the spleen of vaccinated animals. The lack of protection observed may be explained by a significant production of IL-10 induced by the vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Protozoan / genetics
  • Antigens, Protozoan / immunology*
  • Disease Models, Animal
  • Female
  • Injections, Intramuscular
  • Injections, Subcutaneous
  • Interferon-gamma / biosynthesis*
  • Interferon-gamma / immunology
  • Interleukin-10 / biosynthesis
  • Interleukin-4 / biosynthesis
  • Leishmania infantum / immunology
  • Leishmaniasis, Visceral / immunology*
  • Leishmaniasis, Visceral / prevention & control*
  • Liver / parasitology
  • Lymphocytes / immunology
  • Mice
  • Mice, Inbred BALB C
  • Protozoan Proteins / genetics
  • Protozoan Proteins / immunology*
  • Protozoan Vaccines / administration & dosage
  • Protozoan Vaccines / immunology*
  • Spleen / parasitology
  • Vaccines, DNA / administration & dosage
  • Vaccines, DNA / immunology*

Substances

  • Antigens, Protozoan
  • Protozoan Proteins
  • Protozoan Vaccines
  • Vaccines, DNA
  • Interleukin-10
  • LACK antigen, Leishmania
  • Interleukin-4
  • Interferon-gamma