Leishmania infantum sterol 24-c-methyltransferase formulated with MPL-SE induces cross-protection against L. major infection

Vaccine. 2009 May 11;27(21):2884-90. doi: 10.1016/j.vaccine.2009.02.079. Epub 2009 Mar 9.

Abstract

The enzyme sterol 24-c-methyltranferase (SMT) is required for the biosynthesis of ergosterol, the major membrane sterol in Leishmania parasites. SMT and ergosterol are not found in mammals, so this protein may be an attractive target for anti-leishmanial vaccines and drugs. We have previously demonstrated that SMT from L. infantum, which causes visceral leishmaniasis, is a protective antigen against this parasite. Because this protein is highly conserved among Leishmania species, we evaluated the potential of SMT to cross-protect against a different form of leishmaniasis. Here, we show that immunization with L. infantum SMT, formulated with monophosphoryl lipid A in stable emulsion (MPL-SE), protects mice from cutaneous leishmaniasis caused by L. major. In BALB/c mice the vaccine preparation induced antigen-specific multi-functional CD4(+) T cells capable of producing IFN-gamma, IL-2, and/or TNF-alpha upon antigen re-exposure, and MPL-SE was indispensable to direct immune responses to SMT towards Th1. Mice immunized with the SMT/MPL-SE vaccine developed significantly smaller lesions following ear challenge with L. major. These results suggest that SMT is a promising vaccine antigen for multiple forms of leishmaniasis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Protozoan / immunology
  • Cells, Cultured
  • Cricetinae
  • Cross Reactions / immunology
  • Emulsions
  • Female
  • Leishmania infantum / enzymology*
  • Leishmania infantum / immunology*
  • Leishmania major / immunology*
  • Leishmaniasis, Cutaneous / immunology*
  • Leishmaniasis, Cutaneous / prevention & control*
  • Methyltransferases / genetics
  • Methyltransferases / immunology*
  • Methyltransferases / metabolism*
  • Mice
  • Th1 Cells / immunology
  • Th2 Cells / immunology

Substances

  • Antigens, Protozoan
  • Emulsions
  • Methyltransferases
  • delta 24-sterol methyltransferase