Neutralize the killers and cure diabetes
In autoimmune diseases, including type 1 diabetes, T-killers attack their own cells, while another type of lymphocytes tries to protect the body from this attack.
Researchers from the Joslin Diabetes Center of Harvard Medical School (Harvard Medical School Joslin Diabetes Center) in experiments on mouse models of type 1 diabetes demonstrated the role of regulatory T-lymphocytes in the progression of the disease.
Most T-lymphocytes mature in the thymus (hence the first letter in the cell name). But a small population of cells is formed outside the thymus – these are peripheral induced T-lymphocytes (peripherally induced T regulatory, pTreg).
The authors of the study claim that pTreg plays a key role in the development of type 1 diabetes mellitus. They believe that in the intestine, where pTreg mainly ripen, the microflora can contribute to the formation of these cells, thus protecting the pancreas from the attack of T-killers. Previous studies have shown a correlation between the state of the intestinal flora and the risk of type 1 diabetes mellitus.
When studying the role of pTreg in protecting against diabetes mellitus, it was found that pTreg was present in the pancreas and the lymph node closest to it. This lymph node was also anatomically close to the part of the intestine in which pTreg ripen.
The authors write that the lymph node of the pancreas is the main base where T–killers accumulate and activate against their body. Migration of pTreg into it probably inactivates T-killers and protects pancreatic tissues from autoimmune attack.
Mice with diabetes mellitus had the DNA region responsible for the production of pTreg removed using the CRISPR/Cas9 genome editing system. These mice had a normal number of T-lymphocytes maturing in the thymus and significantly less pTreg. Their tendency to develop autoimmune diabetes was higher than in unmodified mice.
Now the aim of the authors is to test the hypothesis about the influence of the role of intestinal microflora on the risk of diabetes mellitus. To do this, it is planned to completely "clean" the intestines of bacteria, and then alternately populate it with different strains and monitor the state of the immune system and pancreas.
Currently, a study is being conducted on the effect of T-regulatory cells matured in the thymus on reducing autoimmune damage to the pancreas.
All the work carried out in case of a positive result can provide justification for the development of new methods of treatment of type 1 diabetes mellitus. Especially impressive is the possibility of avoiding hormone therapy and direct intervention in the immune system – if it is proved that the intestinal flora is able to influence the course of diabetes.
The article by C. Schuster et al. Periodically-induced regulatory T cells contribute to the control of autoimmune diabetes in the NOD mouse model is published in the European Journal of Immunology.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the Joslin Diabetes Center: Risk of type 1 diabetes climbs when one population of T cells falls.