Autoimmune diseases: deceive T-lymphocytes
Canadians have developed a "paradoxical" nanovaccine against autoimmune diseasesCopper news
Canadian scientists have developed a nanovaccine against a person's own immune cells for the treatment of autoimmune diseases.
In an experiment on mice, this vaccine has shown its effectiveness in the treatment of type 1 diabetes, writes Scientific American (Counterintuitive Cure: A Nanovaccine That Stops Autoimmune Disease by Boosting the Immune System).
When a microbe enters the body, its antigens (proteins and glycoproteins) are "read" by antigen-presenting cells (APC). After receiving the information, these cells transmit it to T-lymphocytes attacking the infectious agent and activate them. In autoimmune diseases of the agro-industrial complex, for one reason or another, they begin to perceive antigens of some kind of their own cells of the body as foreign and adjust immunity against them. Dying cells "supply" the APC with even more of their antigens, thus closing the "vicious circle" leading to a chronic disease.
At the same time, two populations of T-lymphocytes appear in the immune system with opposite tasks: one – stronger and more aggressive – attacks its own cells, and the other – weaker – tries to destroy the APC, carrying information about the antigens of these cells, suppressing excessive activity of the immune system.
Diabetes specialist Pere Santamaria from the University of Calgary in Alberta has found a fundamentally new, at first glance paradoxical approach to the treatment of autoimmune diseases. Instead of suppressing the immune system, as is usually done, he decided to stimulate it.
To do this, Santamaria and colleagues created nanoparticles coated with antigens of beta cells of the pancreas that produce insulin (these cells are attacked by the immune system in type 1 diabetes). When "weak" T-lymphocytes encounter a large number of these antigens, they begin to actively attack the APC, depriving "strong" lymphocytes of a source of information. (How this happens is shown in the diagram from an article in the journal Immunity: Sue Tsai et al., Reversal of Autoimmunity by Boosting Memory-like Autoregulatory T Cells – VM).
Since the "weak" live longer than the "strong", after a while the "vicious circle" breaks, which leads to the termination of the disease.
Nanoparticles were chosen as a carrier of antigens because they are able to retain them in the body for a long time, which allows reducing the frequency of administration and the dose of the vaccine.
In an experiment conducted by scientists, the vaccine effectively protected mice with a hereditary predisposition to diabetes from diabetes and cured animals already suffering from this disease.
Currently, the Santamaria team plans to move to human trials, as well as create similar nanovaccines against other autoimmune diseases, such as multiple sclerosis and rheumatoid arthritis.
Portal "Eternal youth" http://vechnayamolodost.ru12.04.2010