The overall objectives of this proposal are twofold: (l) to identify and characterize carbohydrate and protein antigens of Leishmania major involved in induction of host-protective immune responses or which are key molecules obligatory for initiating infection of the host macrophage; (2) to clone, characterize and express genes for the protein antigens in order to allow production of these molecules for vaccination studies in our mouse-L.major model system. Specifically, the glycolipid molecule on the surface of the amastigote which is the receptor for the host macrophage will be biochemically characterized in terms of its composition, synthesis, transport to the macrophage surface and association with host MHC molecules. The role of this glycolipid in determining tissue tropism and as a potential vaccine molecule will be studied. These studies will provide new information on a key parasite molecule which is critical for the host-parasite interaction and will assess this molecule as a vaccine. In addition, stage-specific and strain specific cDNA sequences will be isolated and characterized in terms of their transcription, gene structure and sequence. These sequences which represent good candidates to encode host protective antigens will be expressed to allow indentification of the encoded protein and vaccination studies in mice. Polymorphic gene sequences will be used as genomic markers for the genotypic taxonomy of Leishmania. The molecular karyotyping of Leishmanis using pulsed field gradient gel electrophoresis to separate chromosomes will permit the analysis of the genetic content of individual chromosomes. These molecular genetic studies will integrate with the immunochemical studies to provide fundamental new insights into antigens and genes of Leishmamis which are critically involved in determining the host parasite relationship. This proposal thus emphasizes the use of both glycolipid and protein molecules in the development of a defined Leishmania vaccine. This reflects the belief that for genetically diverse parasites and hosts a multivalent vaccine will be necessary to achieve protection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI019347-06
Application #
3128716
Study Section
Tropical Medicine and Parasitology Study Section (TMP)
Project Start
1983-01-01
Project End
1989-08-31
Budget Start
1988-09-01
Budget End
1989-08-31
Support Year
6
Fiscal Year
1988
Total Cost
Indirect Cost
Name
Royal Melbourne Hospital
Department
Type
DUNS #
City
Melbourne
State
Country
Australia
Zip Code
Symons, F M; Murray, P J; Ji, H et al. (1994) Characterization of a polymorphic family of integral membrane proteins in promastigotes of different Leishmania species. Mol Biochem Parasitol 67:103-13
Morris, L; Aebischer, T; Handman, E et al. (1993) Resistance of BALB/c mice to Leishmania major infection is associated with a decrease in the precursor frequency of antigen-specific CD4+ cells secreting interleukin-4. Int Immunol 5:761-7
Morris, L; Troutt, A B; McLeod, K S et al. (1993) Interleukin-4 but not gamma interferon production correlates with the severity of murine cutaneous leishmaniasis. Infect Immun 61:3459-65
Handman, E; Barnett, L D; Osborn, A H et al. (1993) Identification, characterisation and genomic cloning of a O-linked N-acetylglucosamine-containing cytoplasmic Leishmania glycoprotein. Mol Biochem Parasitol 62:61-72
Cappai, R; Osborn, A H; Gleeson, P A et al. (1993) Cloning and characterization of a Golgi-associated GTP-binding protein homologue from Leishmania major. Mol Biochem Parasitol 62:73-82
Aebischer, T; Moody, S F; Handman, E (1993) Persistence of virulent Leishmania major in murine cutaneous leishmaniasis: a possible hazard for the host. Infect Immun 61:220-6
Mosser, D M; Handman, E (1992) Treatment of murine macrophages with interferon-gamma inhibits their ability to bind leishmania promastigotes. J Leukoc Biol 52:369-76
Kelleher, M; Bacic, A; Handman, E (1992) Identification of a macrophage-binding determinant on lipophosphoglycan from Leishmania major promastigotes. Proc Natl Acad Sci U S A 89:6-10
Morris, L; Troutt, A B; Handman, E et al. (1992) Changes in the precursor frequencies of IL-4 and IFN-gamma secreting CD4+ cells correlate with resolution of lesions in murine cutaneous leishmaniasis. J Immunol 149:2715-21
Rainey, P M; Spithill, T W; McMahon-Pratt, D et al. (1991) Biochemical and molecular characterization of Leishmania pifanoi amastigotes in continuous axenic culture. Mol Biochem Parasitol 49:111-8

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