Immunization with Leishmania infantum released proteins confers partial protection against parasite infection with a predominant Th1 specific immune response.

Abstract

In this study, protective effect and immune response elicited by protein fractions LiRic1 (>75 kDa) and LiRic2 (<37 kDa) released by Leishmania infantum promastigotes were analysed in challenged BALB/c mice. Viable parasites were quantified in spleen and isolated CD4(+) and CD8(+) T cells were stimulated for evaluation of proliferative response and cytokine production. Immunization triggered 50.4-66.9% of parasite reduction. Stimulated CD4(+) T cells from challenged animals revealed high proliferation. IL-12 and IFN-gamma were released by CD4(+) T cells whereas IL-4 and IL-10 were impaired. LiRic1 and LiRic2 immunization gave partial protection and a CD4(+) Th1 response. LiRic2 generated IL-12 by CD8(+) T cells pointing to its participation in protective response. These results encourage further research on the development of a vaccine that provides long-lasting protection against zoonotic visceral leishmaniasis.

• Authors: Ricardo Rosa, Cláudia Marques, Olivia Roos Rodrigues, Gabriela M Santos-Gomes
• Journal: Vaccine (Vaccine) Vol. 25 Issue 23 Pg. 4525-32 (Jun 06 2007) ISSN: 0264-410X [Print] Netherlands
• PMID: 17478016 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Protozoan Proteins
• Interleukin-12
• Interferon-gamma

Topics

• Animals
• CD4-Positive T-Lymphocytes (immunology)
• Immunization
• Interferon-gamma (biosynthesis)
• Interleukin-12 (biosynthesis)
• Leishmania infantum (immunology)
• Leishmaniasis, Visceral (immunology, prevention & control)
• Lymphocyte Activation
• Mice
• Mice, Inbred BALB C
• Protozoan Proteins (immunology)
• Spleen (parasitology)
• Th1 Cells (immunology)