A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae

• Published in: Nature communications Vol. 6; no. 1; p. 7403
• Main Authors: Ramirez, Jose Luis, de Almeida Oliveira, Giselle, Calvo, Eric, Dalli, Jesmond, Colas, Romain A., Serhan, Charles N., Ribeiro, Jose M., Barillas-Mury, Carolina
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 23.06.2015; Nature Publishing Group; Nature Pub. Group; Nature Portfolio
• Subjects: 13; 38; 38/89; 631/250/2152/1566/1571; 631/250/255/1715; 631/250/262; 631/45/612/1237; 82; 82/16; 82/58; 82/83; Animals; Anopheles - immunology; Anopheles gambiae; Arachidonic acid; Culicidae; Differentiation; Hemocytes; Hemolymph; Humanities and Social Sciences; Immune system; Immunity, Innate - immunology; Innate immunity; Insect Vectors - immunology; Insects; Lipids; Lipocalin; Lipocalins - immunology; Lipoxin A4; Lipoxins - immunology; Midgut; Molecular modelling; Mosquitoes; multidisciplinary; Plasmodium; Plasmodium berghei - immunology; Priming; Science
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms8403

Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to ‘remember’ a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A 4 . Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. A soluble factor induced by Plasmodium infection promotes hemocyte differentiation and increases mosquitoe resistance to subsequent infections. Here the authors show that this factor consists of a Lipocalin/Lipoxin A4 complex, and that insects can metabolize arachidonic acid to produce lipoxins.