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Epithelial nitration by a peroxidase/NOX5 system mediates mosquito antiplasmodial immunity.

ABSTRACT: Plasmodium ookinetes traverse midgut epithelial cells before they encounter the complement system in the mosquito hemolymph. We identified a heme peroxidase (HPX2) and NADPH oxidase 5 (NOX5) as critical mediators of midgut epithelial nitration and antiplasmodial immunity that enhance nitric oxide toxicity in Anopheles gambiae. We show that the two immune mechanisms that target ookinetes-epithelial nitration and thioester-containing protein 1 (TEP1)-mediated lysis-work sequentially, and we propose that epithelial nitration works as an opsonization-like system that promotes activation of the mosquito complement cascade.

SUBMITTER: Oliveira Gde A

PROVIDER: S-EPMC3444286 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Epithelial nitration by a peroxidase/NOX5 system mediates mosquito antiplasmodial immunity.

Oliveira Giselle de Almeida Gde A Lieberman Joshua J Barillas-Mury Carolina C

Science (New York, N.Y.) 20120126 6070

Plasmodium ookinetes traverse midgut epithelial cells before they encounter the complement system in the mosquito hemolymph. We identified a heme peroxidase (HPX2) and NADPH oxidase 5 (NOX5) as critical mediators of midgut epithelial nitration and antiplasmodial immunity that enhance nitric oxide toxicity in Anopheles gambiae. We show that the two immune mechanisms that target ookinetes-epithelial nitration and thioester-containing protein 1 (TEP1)-mediated lysis-work sequentially, and we propos ...[more]

PMID: 22282475

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