Effective nano-therapy fights cancer, inflammatory disorders

The research suggests that it is possible to use a group of proteins present in blood plasma (liquid portion of the blood) as carrier vehicles of iron nanoparticles to direct them towards a group of cells known as macrophages that belong to the immune system.

Vizcaya Ruiz, who is also coordinator of the Department of Toxicology Research Center for Advanced Studies (CINVESTAV), performed this work with doctoral student Vicente Escamilla Rivera.

During the research they found that when introducing iron nanoparticles in a biological media such as blood, its surface is immediately covered by a layer of biomolecules known as a "crown protein."

Vizcaya evaluated whether this interaction could be used to guide the nanoparticles to organs rich in macrophages using proteins from the complement system, which is one of the vital parts of the immune system response to the entry of invaders.

They used three kinds of nanoparticles of iron oxide: two of them were coated with polymers (polyethylene glycol and polyvinylpyrrolidone) and the other had no coating. The team found that the interaction between these and the blood plasma proteins favors the accumulation of macrophages.

In addition, their in vitro tests found that the biocompatibility was higher when using nanoparticles coated with polyethylene glycol, which helped to make more efficient and with fewer side effects the anti-cancer therapies. Furthermore, with the coating formed by the crown protein toxicity was reduced.

Subsequently, they used an experimental model in animals and found that by attracting and retaining proteins of the complementary system, the nanoparticles accumulated mostly in organs rich in macrophages, such as the liver and spleen, additional to inducing the activation of the immune system.

The discovery of Vizcaya could be applied in future human clinical trials; for example, in the design of nanoparticles containing activators of the above proteins of the complementary system, so they can directly strike the desired cell target.

Also, the immune system activation induced by the nanoparticles coated with polyethylene glycol may be used in addition to stimulating the host's response to infectious diseases.