IMUNE RESPONSE OF NANOPARTICULATED SYSTEMS

IMUNE RESPONSE OF NANOPARTICULATED SYSTEMS
Dávia Bortollia
Inaê Montibeller Cavalcaa
Maria Veronica Davila Pastora
Rilton Alves de Freitasa

aCurso de Farmácia, Universidade do Vale do Itajai, CEP 88302-202, Itajaí -SC Brasil

ABSTRACT
Nanoparticles, originated from biomolecules of chitosan and their derivatives, are being used as agents that promote the control on drugs release, of drugs which have physico-chemical problems or remain in the body not enough time to complete their pharmacological action or have an efficient action.
The compounds were tested in macrophages, cells of the immune system that incorporate foreign particles and cellular debris. These cells can be activated, among other ways in the presence of bacterial LPS, or through direct contact with certain microorganisms or inert particles. When activated, macrophages release mediators and other products that promote their anti-bacterial function, as nitric oxide (NO). Macrophages recognition of nanoparticles can be minimized using bio-compatible materials.
Our results showed that nanoparticulated systems investigated did not alter the cell viability, suggesting that these systems have no cytotoxic potential. Macrophage activation was evaluated by presence of nitric oxide in the cell culture supernatant, in the presence or absence of LPS. The incorporation of the nanoparticles by macrophages was investigated, in vitro, with fluorescent nanospheres. Cells grown without LPS showed more nanospheres incorporation when compared with those grown with LPS. This may be related to competitive inhibition of the CD14 receptor, with LPS. Therefore, the transport of chitosan and its compounds may be dependent on CD14 activation, in addition of manose receptor.
Additional studies are necessary to determine the mechanism of nanoparticles incorporation by macrophages and the effect of those particles on other cells of the immune system.
Keywords: Nanotechnology. Chitosan. Macrophage activation. Immune