Characterization of a defensin from the sand fly Phlebotomus duboscqi induced by challenge with bacteria or the protozoan parasite Leishmania major.

ABSTRACT: Antimicrobial peptides are major components of the innate immune response of epithelial cells. In insect vectors, these peptides may play a role in the control of gut pathogens. We have analyzed antimicrobial peptides produced by the sand fly Phlebotomus duboscqi, after challenge by injected bacteria or feeding with bacteria or the protozoan parasite Leishmania major. A new hemolymph peptide with antimicrobial activity was identified and shown to be a member of the insect defensin family. Interestingly, this defensin exhibits an antiparasitic activity against the promastigote forms of L. major, which reside normally within the sand fly midgut. P. duboscqi defensin could be induced by both hemolymph or gut infections. Defensin mRNA was induced following infection by wild-type L. major, and

SUBMITTER: Boulanger N 

PROVIDER: S-EPMC529173 | biostudies-literature | 2004 Dec

REPOSITORIES: biostudies-literature