Article
Neutrophil paralysis in Plasmodium vivax malaria
Registro en:
LEORATTI, Fabiana Maria de Souza et al. Neutrophil paralysis in Plasmodium vivax malaria. Plos Neglected Tropical Diseases. 2012, vol.6, pp. e1710
1935-2735
10.1371/journal.pntd.0001710
Autor
Leoratti, Fabiana Maria de Souza
Trevelin, Silvia Cellone
Cunha, Fernando Queiroz
Rocha, Bruno Coelho
Costa, Pedro Augusto Carvalho
Gravina, Humberto Doriguêtto
Tada, Mauro Shugiro
Pereira, Dhelio Batista
Golenbock, Douglas Taylor
Antonelli, Lis Ribeiro do Valle
Gazzinelli, Ricardo Tostes
Resumen
Background
The activation of innate immune responses by Plasmodium vivax results in activation of effector cells and an excessive production of pro-inflammatory cytokines that may culminate in deleterious effects. Here, we examined the activation and function of neutrophils during acute episodes of malaria.
Materials and Methods
Blood samples were collected from P. vivax-infected patients at admission (day 0) and 30–45 days after treatment with chloroquine and primaquine. Expression of activation markers and cytokine levels produced by highly purified monocytes and neutrophils were measured by the Cytometric Bead Assay. Phagocytic activity, superoxide production, chemotaxis and the presence of G protein-coupled receptor (GRK2) were also evaluated in neutrophils from malaria patients.
Principal Findings
Both monocytes and neutrophils from P. vivax-infected patients were highly activated. While monocytes were found to be the main source of cytokines in response to TLR ligands, neutrophils showed enhanced phagocytic activity and superoxide production. Interestingly, neutrophils from the malaria patients expressed high levels of GRK2, low levels of CXCR2, and displayed impaired chemotaxis towards IL-8 (CXCL8).
Conclusion
Activated neutrophils from malaria patients are a poor source of pro-inflammatory cytokines and display reduced chemotactic activity, suggesting a possible mechanism for an enhanced susceptibility to secondary bacterial infection during malaria.