Biochemical and biological characterization of the protective Leishmania pifanoi amastigote antigen P-8.

Abstract

The Leishmania pifanoi amastigote antigen P-8 has been previously shown to induce protective immunity in a murine model of cutaneous leishmaniasis (L. Soong, S. M. Duboise, P. Kima, and D. McMahon-Pratt, Infect. Immun. 63:3559-3566, 1995). As this antigen is of interest for further vaccine studies, the biochemical characterization of P-8 was undertaken. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western-blot analysis, and gel filtration chromatography revealed that P-8 antigen consisted of two proteoglycolipid complexes. The P-8 epitope is associated with the L. pifanoi amastigote-specific glycolipid components found in the two complexes. The P-8 complex 1 (P-8c1) consists of a 56-kDa serine metalloproteinase, apolipoprotein E (derived from fetal bovine serum), and amastigote-specific glycolipids. The P-8 complex 2 (P-8c2) consists of a 31-kDa cysteine proteinase associated with amastigote glycolipids. Biochemical analyses suggest that the P-8 antigenic glycolipids may be distinct from previously described Leishmania glycolipids (glycosylinositol-phospholipids and sphingoglycolipids). Protective immunity studies revealed that P-8c1 (serine metalloproteinase-glycolipid complex) confers comparable protection against infection as immunopurified P-8. The isolated P-8c2 (cysteine proteinase-glycolipid complex) does not provide significant protection, nor does stimulation with P-8c2 result in significant T-cell activation in P-8- or P-8c2-vaccinated mice. Consequently, the P-8c1 complex appears to be the immunodominant component of P-8.

• Authors: M Colmenares, M Tiemeyer, P Kima, D McMahon-Pratt
• Journal: Infection and immunity (Infect Immun) Vol. 69 Issue 11 Pg. 6776-84 (Nov 2001) ISSN: 0019-9567 [Print] United States
• PMID: 11598050 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Antigens, Protozoan
• Glycolipids
• Membrane Proteins
• Proteolipids
• Protozoan Proteins
• Protozoan Vaccines
• proteoglycolipids

Topics

• Animals
• Antigens, Protozoan (analysis, immunology)
• Female
• Glycolipids (analysis, immunology)
• Leishmania (immunology)
• Membrane Proteins (analysis, immunology)
• Mice
• Mice, Inbred BALB C
• Proteolipids (analysis, immunology)
• Protozoan Proteins (analysis, immunology)
• Protozoan Vaccines (immunology)