Researchers from the Massachusetts Institute of Technology (USA) to develop a vaccine that does not need to stick a syringe and stored under certain conditions, and in addition, it does not cause a person any discomfort.
This vaccine, in contrast to most of today, uses no viral proteins or bacteria that you want to teach the immune system, and DNA. DNA vaccines in recent years have increasingly attracted the attention of scientists: some are trying to use them to vaccinate people against tooth decay, others – from the flu (although the latter is not used viral DNA and RNA).
|Perhaps in the near future will have to master the skills of Immunologists tattooists. (Photo by Markus Cuff.)|
The advantages of DNA vaccines is that it provides a constant protein production in which immunity can recognize the pathogen. That is a DNA vaccine immune system learns best. However, all the trials of DNA vaccines have demonstrated promising results in animals but not in humans.
One major problem – how to enter the DNA vaccine into human cells, so that it served as a template for protein synthesis. One way would be: a man in skin type of vaccine, and then give an electric shock to open the pores in the cells and let them DNA technique called electroporation. However, for the person it was not just painful, but it is also unpredictable: its effectiveness varied from time to time. If you just enter a DNA vaccine as usual, it can quickly deteriorate, failing to teach the immune system what it should.
At the Massachusetts Institute of went the other way. The scientists mixed the DNA with a special polymer, and it is injected under the skin with a tiny needle. And the needle into the skin of half a millimeter. That was enough to immune cells of the epidermis found DNA, and to nerve needle did not reach, so that the procedure does not cause pain. The whole process resembles a tattoo. In the aquatic environment, the polymer breaks down into fragments, releasing the DNA, each DNA molecule is coupled with a fragment of the polymer, which protects it from destruction and facilitates penetration into the cell.
The release of DNA occurs within a few days or weeks, so that immune cells has enough time to learn, to whom they have to react. We can say that the immune tattoo gradually dissolves, and its rate of absorption depends on the hydrophobic / hydrophilic polymer and the number of polymer layers, which carries the DNA. Polymer structure also contains an adjuvant, so that the stimulation of immunity is even more effective.
In mice and monkeys, as the researchers wrote in the journal Nature Materials, the immune tattoo was more effective than the above-described electroporation. In addition, the DNA introduced in such a way was more durable and does not decay immediately after administration. In general, managed to create a painless, practical and long lasting method of vaccination. But whether this temporary immune "tattoo" effective in us, show times and further experiments.
Prepared according to MIT News.