Avaliação do efeito de nanopartículas de albumina sérica bovina associadas ao ácido poliinosínico-policitidílico poli (I:C) sobre o fenótipo de células dendríticas.

Abstract

Nanoparticles (NPs) are microscopic structures that have dimensions between 1 nm to 100 nm and can act as delivery systems for antigens on vaccine formulations. NPs can have low toxicity when they are inoculated or injected into animals. The toxicity of NPs depends on several factors, such as type of material, route of administration, size and shape. NPs can induce inflammation with involvement of neutrophils, macrophages, dendritic cells and other effector cells. Dendritic cells (DCs) have a fundamental role in mediating the innate immune response and in the induction of the

adaptive immune response. Albumin is a natural, biocompatible, biodegradable, non- toxic and non-immunogenic polymer and, due to these characteristics, albumin NPs

are promising for develop drug or antigen delivery systems. The present work aims to produce and evaluate the effect of bovine serum albumin nanoparticles associated with polyinosinic-polycytidyl acid (NPPI) on the phenotype of bone marrow derived dendritic cells. The particle size, its distribution and the Zeta potential were determined by the dynamic light scattering technique. The morphology of NPs was determined by atomic force microscopy. The BSA nanoparticles containing polyinosinic-polycytidyl acid poly (I: C) have a 497±140,4 nm, -33,66±3,93 mV, PDI of 0,38±0,06 and a spherical shape. Studies for determinate the encapsulation rate indicate that 100% of poly (I: C) encapsulation was obtained. Bone marrow derived cells from C57BL/6 mice were obtained and differentiated into dendritic cells (DCs). DCs were treated with the nanoparticles for 48 hours and the state of activation and maturation of these cells were monitored using qPCR for the IFN-β, CD40 and CD86 mRNAs. The results indicate an increase in mRNA expression of the IFN-β and CD40 genes in cells treated with NPPI. Histopathological analysis of the skin of animals inoculated with NPPI showed recruitment of inflammatory cells in the skin. Therefore, the results demonstrated the potential of NPPI to be used as an adjuvant in vaccine platforms.