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Hemocyte differentiation to the megacyte lineage enhances mosquito immunity against Plasmodium.

ABSTRACT: Activation of Toll signaling in Anopheles gambiae by silencing Cactus, a suppressor of this pathway, enhances local release of hemocyte-derived microvesicles (HdMv), promoting activation of the mosquito complement-like system, which eliminates Plasmodium ookinetes. We uncovered the mechanism of this immune enhancement. Cactus silencing triggers a Rel1-mediated differentiation of granulocytes to the megacyte lineage, a new subpopulation of giant cells, resulting in a dramatic increase in the proportion of circulating megacytes. Megacytes are very plastic cells that are massively recruited to the basal midgut surface in response to Plasmodium infection. We show that Toll signaling modulates hemocyte differentiation and that megacyte recruitment to the midgut greatly enhances mosquito immunity against Plasmodium.

SUBMITTER: Barletta ABF

PROVIDER: S-EPMC9545522 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Hemocyte differentiation to the megacyte lineage enhances mosquito immunity against Plasmodium.

Barletta Ana Beatriz F ABF Saha Banhisikha B Trisnadi Nathanie N Talyuli Octavio A C OAC Raddi Gianmarco G Barillas-Mury Carolina C

eLife 20220902

Activation of Toll signaling in Anopheles gambiae by silencing Cactus, a suppressor of this pathway, enhances local release of hemocyte-derived microvesicles (HdMv), promoting activation of the mosquito complement-like system, which eliminates Plasmodium ookinetes. We uncovered the mechanism of this immune enhancement. Cactus silencing triggers a Rel1-mediated differentiation of granulocytes to the megacyte lineage, a new subpopulation of giant cells, re ...[more]

PMID: 36052991

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