: This proposal is focused upon the intracellular amastigote stage of Leishmania mexicana complex parasites and the immune/inflammatory interactions occurring within the vaccinated host. Vaccination with the P-8 proteoglycolipid complex, which is expressed in the amastigote stage, confers resistance to infection. Studies indicate that CD8+ and CD4+ T cells are critical for resistance/protection against infection in P-8 immunized mice. Recent studies indicate that protection is dependent upon IFNg, perforin-mediated mechanisms and CD1d presentation. In addition, the associated P-8 glycolipids (1-4) directly affect macrophage function (cytokine production and parasite uptake). Consequently, this proposal is focused on elucidating the immune protective mechanisms induced by P-8 vaccination and on the biological roles (structure-function) of the P-8 glycolipids. Specifically, the aims are: 1. Determine the mechanisms by which CDld presentation/NKT activation contribute to the protection against Leishmania infection induced by P-8 vaccination. Using the murine model, the role of CDld presentation and NKT cells in the induction and effector phases of the protective immune response induced by P-8 vaccination will be determined. Further, CD1d-P-8 antigen presentation (kinetics, role of processing) by antigen-pulsed and infected macrophages and dendritic cells will be examined. 2. Investigate the biological function and biochemical characterization of the P-8 amastigote antigen. The P-8 antigen has been demonstrated to be a proteoglycolipid complex. The P-8 glycolipids affect macro-phage morphology and elicit cytokine/chemokine production; these glycolipids appear to be distinct from previously described leishmanial glycolipids. The biochemical structure of the P-8 glycolipids and the receptor (TLR; non-TLR) involved in macrophage activation will be determined. The CD1d -P-8 glycolipid(s) interaction will be investigated and KB determined using competitive binding and/or BIAcor methods. As the P-8cl serine proteinase complex appears to be antigenically important for protection and CD4 T cells contribute to protection, the gene encoding the p56 serine proteinase will be cloned and characterized.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
2R21AI027811-13A1
Application #
6613504
Study Section
Tropical Medicine and Parasitology Study Section (TMP)
Program Officer
Hall, B Fenton
Project Start
1989-04-15
Project End
2004-04-14
Budget Start
2003-04-15
Budget End
2004-04-14
Support Year
13
Fiscal Year
2003
Total Cost
$327,000
Indirect Cost
Name
Yale University
Department
Public Health & Prev Medicine
Type
Schools of Medicine
DUNS #
043207562
City
New Haven
State
CT
Country
United States
Zip Code
06520
Deak, Eszter; Jayakumar, Asha; Cho, Ka Wing et al. (2010) Murine visceral leishmaniasis: IgM and polyclonal B-cell activation lead to disease exacerbation. Eur J Immunol 40:1355-68