Schistosoma mansoniPhosphoenolpyruvate Carboxykinase, a Novel Egg Antigen: Immunological Properties of the Recombinant Protein and Identification of a T-Cell Epitope
Open Access
- 1 June 2000
- journal article
- research article
- Published by American Society for Microbiology in Infection and Immunity
- Vol. 68 (6) , 3385-3393
- https://doi.org/10.1128/iai.68.6.3385-3393.2000
Abstract
In schistosomiasis mansoni, hepatic granulomatous inflammation surrounding parasite eggs is mediated by CD4+T helper (Th) cells sensitized to schistosomal egg antigens (SEA). We previously showed that a prominent lymphoproliferative response of CD4+Th cells from schistosome-infected C57BL/6 (BL/6) mice was directed against a 62-kDa component of SEA. A partial amino acid sequence of the 62-kDa component was found to be identical with one present in the enzyme phosphoenolpyruvate carboxykinase (PEPCK). Based on this sequence, a cDNA clone containing the entire coding region of PEPCK was identified, and the full recombinantSchistosoma mansoniPEPCK (rSm-PEPCK) of 626 amino acids was purified from a prokaryotic expression system. rSm-PEPCK strongly stimulated a specific T-cell hybridoma, 4E6, as well as CD4+Th cells from SEA-immunized BL/6 mice and from infected BL/6, CBA, and BALB/c mice. In the infected mice, rSm-PEPCK elicited significant gamma interferon production as well as, to a lesser extent, production of interleukin-2 and -5. In BL/6 and BALB/c mice, the CD4+Th cell response to rSm-PEPCK was greater than that directed against the egg antigen Sm-p40; conversely, CBA mice responded better to Sm-p40 than to Sm-PEPCK. A 12-amino-acid region (residues 398 to 409: DKSKDPKAHPNS) was demonstrated to contain a T-cell epitope; synthetic peptides containing this epitope significantly stimulated specific hybridoma 4E6 and polyclonal CD4+Th cells. The identification and characterization of immunogenic egg components will contribute to the understanding and possible control of T-cell-mediated schistosomal disease.Keywords
This publication has 45 references indexed in Scilit:
- Schistosome glycoconjugatesBiochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 1999
- Characterization of Schistosoma mansoni 44.756.8 kDa egg antigens recognized by human monoclonal antibodies which induce protection against experimental infection and proliferation of peripheral blood mononuclear cells from schistosomiasis patientsVaccine, 1997
- Phosphoenolpyruvate carboxykinase from Trypanosoma cruzi. Purification and physicochemical and kinetic propertiesMolecular and Biochemical Parasitology, 1995
- Cytokine regulation of T-cell function: potential for therapeutic interventionImmunology Today, 1993
- Truncation variants of peptides isolated from MHC class II molecules suggest sequence motifsNature, 1992
- A stage-specific calcium-binding protein expressed in eggs of Schistosoma mansoniMolecular and Biochemical Parasitology, 1992
- Sequence analysis of peptides bound to MHC class II moleculesNature, 1991
- The enigmatic presence of all gluconeogenic enzymes inSchistosoma mansoniadultsParasitology, 1991
- Downregulation of Th1 cytokine production accompanies induction of Th2 responses by a parasitic helminth, Schistosoma mansoni.The Journal of Experimental Medicine, 1991
- Single-step purification of polypeptides expressed in Escherichia coli as fusions with glutathione S-transferaseGene, 1988