Immunopeptides in the defense reactions of Glossina morsitans to bacterial and Trypanosoma brucei brucei infections

• Published in: Insect biochemistry and molecular biology Vol. 32; no. 4; pp. 369 - 375
• Main Authors: Boulanger, N, Brun, R, Ehret-Sabatier, L, Kunz, C, Bulet, P
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2002; Elsevier
• Subjects: Amino Acid Sequence; Animals; Anti-Bacterial Agents; Anti-Bacterial Agents - pharmacology; Antimicrobial peptides (AMPs); Attacin; Biochemistry, Molecular Biology; Brachycera; Cecropin; Defensin; Escherichia coli; Escherichia coli - drug effects; Glossina spp; Insect immunity; Insect Proteins; Insect Proteins - pharmacology; Life Sciences; Micrococcus luteus; Micrococcus luteus - drug effects; Molecular Sequence Data; Nematocera; Peptides; Peptides - pharmacology; Sequence Homology, Amino Acid; Sleeping sickness; Transgenic insects; Trypanocidal Agents; Trypanocidal Agents - pharmacology; Trypanosoma brucei brucei; Trypanosoma brucei brucei - drug effects; Trypanosoma spp; Tsetse Flies; Antimicrobial peptides (AMPs); Glossina spp; Sleeping sickness; Brachycera; Insect immunity; Cecropin; Transgenic insects; Defensin; Trypanosoma spp; Nematocera; Attacin
• ISSN: 0965-1748; 1879-0240
• DOI: 10.1016/S0965-1748(02)00029-2

Several dipteran insects are vectors of parasites causing major human infectious diseases. Among these, the tsetse fly, Glossina spp., is responsible for the transmission of trypanosomes, the pathogens responsible for sleeping sickness in Africa. A better understanding of insect-parasite interactions will help establish new strategies to fight this important often fatal disease. Antimicrobial peptides (AMPs) are part of the humoral immune response in insects during bacterial, fungal and parasitic infections. Here, we studied the immune response of Glossina morsitans to bacteria and to Trypanosoma brucei brucei by analyzing the synthesis of AMPs as markers of the humoral immune response. By reversed-phase chromatography, mass spectrometry analysis, Edman degradation and in vitro antimicrobial assays of the hemolymph of immune-challenged adults of G. morsitans, we identified three AMPs: a cecropin, an attacin and a defensin. These three AMPs were found to be induced upon systemic bacterial infection and also after per os infections by bacteria and parasites.