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CXCR4 and MIF are required for neutrophil extracellular trap release triggered by Plasmodium-infected erythrocytes.

ABSTRACT: Neutrophil extracellular traps (NETs) evolved as a unique effector mechanism contributing to resistance against infection that can also promote tissue damage in inflammatory conditions. Malaria infection can trigger NET release, but the mechanisms and consequences of NET formation in this context remain poorly characterized. Here we show that patients suffering from severe malaria had increased amounts of circulating DNA and increased neutrophil elastase (NE) levels in plasma. We used cultured erythrocytes and isolated human neutrophils to show that Plasmodium-infected red blood cells release macrophage migration inhibitory factor (MIF), which in turn caused NET formation by neutrophils in a mechanism dependent on the C-X-C chemokine receptor type 4 (CXCR4). NET production was dependent on histone citrullination by peptidyl arginine deiminase-4 (PAD4) and independent of reactive oxygen species (ROS), myeloperoxidase (MPO) or NE. In vitro, NETs functioned to restrain parasite dissemination in a mechanism dependent on MPO and NE activities. Finally, C57/B6 mice infected with P. berghei ANKA, a well-established model of cerebral malaria, presented high amounts of circulating DNA, while treatment with DNAse increased parasitemia and accelerated mortality, indicating a role for NETs in resistance against Plasmodium infection.

SUBMITTER: Rodrigues DAS

PROVIDER: S-EPMC7449500 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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CXCR4 and MIF are required for neutrophil extracellular trap release triggered by Plasmodium-infected erythrocytes.

Rodrigues Danielle A S DAS Prestes Elisa B EB Gama Andreza M S AMS Silva Leandro de Souza LS Pinheiro Ana Acácia S AAS Ribeiro Jose Marcos C JMC Campos Raquel M P RMP Pimentel-Coelho Pedro M PM De Souza Heitor S HS Dicko Alassane A Duffy Patrick E PE Fried Michal M Francischetti Ivo M B IMB Saraiva Elvira M EM Paula-Neto Heitor A HA Bozza Marcelo T MT

PLoS pathogens 20200814 8

Neutrophil extracellular traps (NETs) evolved as a unique effector mechanism contributing to resistance against infection that can also promote tissue damage in inflammatory conditions. Malaria infection can trigger NET release, but the mechanisms and consequences of NET formation in this context remain poorly characterized. Here we show that patients suffering from severe malaria had increased amounts of circulating DNA and increased neutrophil elastase (NE) levels in plasma. We used cultured e ...[more]

PMID: 32797076

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Dataset Information

CXCR4 and MIF are required for neutrophil extracellular trap release triggered by Plasmodium-infected erythrocytes.

Publications

CXCR4 and MIF are required for neutrophil extracellular trap release triggered by Plasmodium-infected erythrocytes.

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