From the start, medical chemistry relies on single molecules with predefined compositions. These molecules target specific receptors in the body. Medicine has evolved a lot since the 19th century. Even after 150 years, we still face this problem with most modern medicine. One type of medication only performs a single function in the body.
This is a problem in the study by scientists for a long time. A lot of research is done since the 70s to find a drug that is, in simple words, capable of Multitasking. These tasks could be the identification of cancer cells in the body. With the help of biochemical cues, Locating tumors, and destroying misbehaving cells with toxins or heat.
As discussed earlier, a single molecule can not perform all these tasks. We need a combination of different units, also known as a Nanoparticle or a Supramolecule. However, we have conquered synthesizing many artificial molecules today. Only a small portion of these are used for medical purposes.
One of the main hurdles in the success of nanoparticles is the human immune system. It is one of nature’s incredible apparatus. Over the past million years of human evolution, our body has learned to keep us safe. Human bodies today eliminate any foreign entity within seconds of it entering our bloodstream. This keeps us safe from many viruses as well as toxic smoke particles.
Now researchers have developed a new method to resolve this problem. This method prolongs the blood circulation of the injected nanoparticle, in turn, making it more effective. Nature Biomedical Engineering published this study by Russian researchers.
Nanoparticles are cleared by the immune system in a matter of minutes when administered to the bloodstream. This means that while developing advanced drugs is essential. We need a way to trick the immune system. So that it does not attack the medicine, but at the same time, no harm occurs to the body.
The team of Russian researchers led by Maxim Nikitin, head of Nanobiotechnology Lab at MIPT, proposed a fix to this problem in their recent paper. They devised a method that increases the blood circulation of the nanoagents without any chemical change to them. This, in turn, increases their efficiency.
The discovery is based on a simple concept that our immune system eliminates dead red blood cells continuously. Explaining the invention, Maxim Nikitin said:
“We hypothesized that if we slightly intensified this natural process, we could trick the immune system. While it becomes busy clearing red blood cells, less attention is given to the clearance of the therapeutic nanoparticles.”
In this way, the team was successful in increasing the effect of medicine without any harm to internal systems in the body. To verify this hypothesis, the team experimented on mice. They injected mice with antibodies that will only attack red blood cells.
A small dose of 1.25 mg/Kg of weight proves exceptionally useful as it increases the blood circulation of nanoparticles twelve times. The measured side effects of this treatment were also very low. The subjects had only a 5 percent drop in their red blood cell counts, which is far from a severe condition.
The study confirmed that this approach, known as cytoblockade of the mononuclear phagocyte system, could be used for most of the nanoparticles. It increased the blood circulation of nanoparticles, having a variety of sizes. In addition to increased efficiency, cytoblockade renders no damage to the body’s ability to fight off other pathogens in the bloodstream.
One of the new nanoparticle applications made possible by this is using the antibody against the CD4 receptor that identifies T cells. Propper drug delivery will ensure better treatment for autoimmune and other diseases. In mice, the researchers increased nanoparticle circulation from five minutes to over an hour with the help of Cytoblockade. The agents showed greater targeting efficiency than before.
The team also showed how this technology could be used for the treatment of cancer. It enhances drug delivery to tumors by twenty-three times. They used a technique that utilizes magnetic fields to guide nanoparticles to cancer. They reported successful therapy of melanoma using liposomes loaded with magnetite and the chemotherapy drug doxorubicin.
This new technology also gave improvement to commercially available liposomal agents approved for human use. This means that the cytoblockade could revolutionize and improve our existing medical techniques. Co-author Ivan Zelepukin commented:
“We observed an improved nano agent delivery with each type of cancer that we ran experiments for. It is particularly important that the method worked on human tumor cells introduced into mice,”
The authors also mention that the enhanced nanoparticle performance closely correlated with the prolongation of blood circulation time. This non-invasive method of particle elimination can also help in various medical studies. The researchers said that this method would enable them to make advanced measurements. It has opened up a new dimension of the study.
Human use of this technology will also begin soon. The antibodies used are already approved for the treatment of immune thrombocytopenia and the prevention of rhesus disease. Maximum Nikitin seemed pretty positive for human applications.
He said, “Now that this complex seven-year study has been published, we will make every effort to translate it into clinical practice. For this reason, we are seeking collaborators and active colleagues interested in joining the team.”
Cytoblockade technology can be applied to any medication because of its universal nature. It can now prove to be more effective than our existing method called PEGylation, which is about 30 years old now. The authors of the article believe that this technology has the potential to open doors for new scientific frontiers.