Brain disease is difficult to treat not only because it is the most complex organ of our body. It is also the most protected: even blood vessels are not associated with the tissues of the central nervous system, separating from them by the cells of the hematostephalic barrier. The permeability of the BGB is selective: oxygen and nutrients it passes, but does not miss toxins, viruses and other potentially dangerous agents. However, it does not allow to get to the brain and a variety of beneficial substances.
It is not surprising that scientists of different countries are trying to create a means of overcoming the BBB: for example, hollow nanoparticles that could penetrate the brain cells, delivering a medicine inside and release it already in place. And the Team of Zhiganana (Zhiguang Wu) from Harbin University has collected for this whole microbot. They talked about their development in an article published in the SCience Robotics magazine.
Scientists called the system "neutrobot", because for the assembly, fragments of neutrophils, immune blood cells are used. It happens as follows. At first, the authors prepared microscopic and elastic particles of "Magnetic Nangel": their polymer frame, which has magnetic properties, can gain quite quantities of water along with the necessary medicine. Next, the cells of the bacteria of the intestinal sticks were killed and "rubbed", removing everything too much and leaving only fragments of cell membranes. They covered gel particles.
Immunity bacterial membrane acts "like a red rag." Therefore, when the prepared particles were mixed with neutrophils, they quickly attacked them and phagocytosis was performed, absorbing a potentially dangerous object. Thanks to the magnetic properties of nangel, their movement can be controlled by affecting an outer magnetic field to direct cells into the brain. Through the BC neutrophils are able to pass easily and independently, being attracted inflammation signals from the patient brain. With you, they carry and useful drug cargo.
The performance of their "neutrobots" scientists demonstrated not only "in a test tube", but also on living laboratory mice - a model line, which is used for glyoma studies, brain tumors. Nangel particles were loaded by the anticancer preparation by Paklitaxel, placed in bacterial membranes and neutrophils, and then already ready-made "neutrobots" were injected into the tail vein. It was soon fixed that those really overcame the BC and delivered a medicine in the tissue of the central nervous system.
Now the authors plan to engage in refinement and improvement of their system. First of all, scientists are interested in the process of managing the movements of "neutrobots" and control over their movement. While the magnetic field acts quite widely, directing in the desired side the whole mass of such microscopic systems and losing many particles along the road.
Source: Naked Science