P-73 - Neutrophils activation by carbon nanotubes functionalized with COOH-groups and conjugated with DNA

Abstract

Interaction of neutrophils with carbon nanotubes (CNT), 100–400 nm in length, functionalized with -COOH groups and non-covalently functionalized with DNA molecules, were investigated by means of Raman spectroscopy, luminol- and lucigenin-enhanced chemiluminescence, and fluorescence microscopy. It was shown that multi-walled CNT with COOH-groups and conjugated with DNA do not accumulate in neutrophils but induce reorganization of cells actin filaments and lead to neutrophils activation. It was established that according to the type of CNT and the method of CNT functionalization they are able to regulate the redox activity of neutrophils. We found that the interaction of double-walled CNT/DNA complexes with cells leads to an enhancement of superoxide generation, but the total amount of free radicals generated by neutrophils remains unaffected. Under the action of multi-walled CNT functionalized with - COOH groups on non-adherent neutrophils, NADPH oxidase is activated as well as an enhancement of the reactive oxygen and chlorine species generation is observed. The interaction of these CNT with neutrophils, stimulated with fMLP and adhesion, leads to the superoxide yield decrease. Thus, CNT could regulate the activation and redox processes in neutrophils.