Gut microbes that generate cells to protect against autoimmune attack could be used to help reduce the risk of type 1 diabetes, according to researchers.
Scientists from the Joslin Diabetes Center report that protective T regulatory cells (pTregs) try to defend against autoimmune attack, which in the case of type 1 diabetes occurs when the body’s T cells mistakenly attack the body’s own cells.
Most T cells develop in the thymus, a small organ above the heart, but pTregs form outside the thymus. The researchers hypothesise that gut microbes affect pTregs because this is where most of the cell population is activated.
By activating the pTreg cell populatio, the autoimmune attack behind type 1 diabetes could be prevented, helping to protect insulin-producing beta cells in the pancreas.
“We are the first to demonstrate that these pTregs are important in autoimmune diabetes,” said senior author Stephan Kissler, Ph.D., an Investigator in Joslin’s Section on Immunobiology.
“Most of these pTregs are made in the gut. We know both that gut microbes promote the development of pTregs, and that gut microbes have an impact on type 1 diabetes.”
Studies on mice and some human research trials have demonstrated how variations in gut microbe populations affect the risk of developing autoimmune conditions.
In one trial, Kissler’s team created non-obese diabetic mice models of type 1 diabetes and modified their genetics to produce less pTregs, which significantly increased their likelihood of developing autoimmune disease.
Clinical trials are currently underway to assess if large samples of pTregs could be exploited to protect against type 1 diabetes, and whether this could lead to new drug treatments.
“If we find that these cells are induced by bacteria, and then find which bacterial products affect that process, we might be able to bypass the complexity of changing the gut microbes and instead intervene directly to increase the pTregs,” said Kissler.
The findings appear in the European Journal of Immunology.