Miosinas e iNOS em macrófagos: análise da expressão e localização em macrófagos ativados e durante fagocitose de Toxoplasma gondii

Abstract

Phagocytosís is a process developed by macrophages and other phagocytes that are important in the destruction o f many foreign agents. Although, some intracellular pathogens, like Toxoplavm, g m J ii, are able to aetively get into host cell and inhibit the fusion of phagosomes and lísosomes. In addition. during T. gondii invasion o f macrophages there is no extensíons o f the membrane, or aetin cytoskeleton rearrangement in host cell. In contrast with phagocytosís o f dead parasite, opsonized or not, invasion by T. g o „ M depcnds on ,he aetin cytoskeleton o f the parasite, but no. o f host cell. Many stndies have Show,, the involvement o f cytoskeleton and myosíns in itnportan, events for hos, cell, suei, as migration, phagocyosis, vesicle traffle, and signal transduction. Myosin I is found ,o be , -ind is concentrated on perinuclear region and 'nvoíved in migration and phagocytosís events and is con , I ín vn lvp d in vesicie movement on aetin filaments and is cortex. Myosin V is found to be mvolvtd in vtsiuu , , c n rtC K r e íí io n . The airn o f tliis work is analyze the distributed all over the cytoplasm and cortex rey o r « P„„Se o f 1774 macrophages to stimuli /» and/or to Interaction with /: g 0 K l í i , ■rongh the determina,ion o f the produetion o f nitric oxide (NO) by dosage in snpernatants r i_ tpín Pxnression o f nitric oxide synthase (NOS) and the ° f cultured celis, trough the protein p ui and trough observation o f the distribution of Wosins I, II, V and VI by Western blotti g, „ The murine macrophage J774 presented myosins Wosins I and V by immunefluorescence. The munn T • r, roincident with iNOS expression in the different V and VI, which expression were • « Pd the produetion o f NO by J774 ceiís, aíone or by treatments on these celis. IFN-y in c r e , the amount o f spreaded celis after 48- hour of «rstimulation. In addition, IFN-y increased the amo P a.cínn o f T. gondii on macrophage membrane. [reatment and increased the percentage o a • ■ nseudopodia and phagosomes formed during Myosins I e V localized, mainly P • w e re diffused labeled during invasion of ’'lagocytosís. Although, both myosin54 macrapbages by T. gvndii. Resul.s sugges. tha. IFN-y is a po.en, activa.or o f macrapbages J774 and tha. myosins I and V participale on phagocytosis of dead parasite.