A new study published in Cell Metabolism reveals that a subpopulation of insulin-making beta cells can resist immune system attacks while type 1 diabetes is developing.
In type 1 diabetes, the immune system attacks the insulin producing beta cells, which over time largely stop being created by the pancreas due to it being a seemingly futile effort. However, some patients with type 1 even after many years, still have some existing beta cells.
A YaleNews press release states that according to researchers, finding more about these cells may guide the way to recovering these cells in patients with diabetes.
diaTribe wrote about this study in which the scientists refer to these special beta cells as Btm cells. Apparently, these cells are different from the others.
They explain that researchers found how in non-obese diabetic mice, pancreatic islets infiltrates like pro-inflammatory cytokines, auto-reactive T cells, and inflammatory mediators all cause this subpopulation of mature beta cells to further multiply and grow and to avoid being killed off by the immune system.
What happens is that these Btm cells avoid immune attack by down-regulating markers of mature beta cells and diabetogenic antigens while up-regulating immune-modulating markers like Qa-2 and PD-L1 which inhibit T cells.
Btm cells are less differentiated and have stem-like features.
Close Concerns wrote, “The researchers further determined that human beta cells from non-diabetic donors cultured with immune cells from patients with diabetes yield a subpopulation similar to the Btm cells in NOD mice – this is very exciting that similar immune attack-resistant beta cells can be cultivated from human samples.”
The study’s lead author, Dr. Kevan Herold of Yale University told Close Concerns that this different kind of beta cell may explain the “chronic nature of diabetes and beta cell maintenance in patients with type 1 diabetes”.
Two Kinds of Beta Cells?
In the press release, Dr. Herold said, “During the development of diabetes, there are changes in beta cells so you end up with two populations of beta cells,” and that “One population is killed by the immune response. The other population seems to acquire features that render it less susceptible to killing.”
To follow on this, researchers plan to “tackle insulin-production in this beta cell subpopulation”, which Close Concerns write is necessary if scientists are to harvest Btm cells in place of stem cells for type 1 cell transplant therapies.
An interesting detail is that these Btm cells were noticed in part by their “lower insulin content”, which is something that will need to be addressed fully in a future study.
This subpopulation survives, according to the Yale press release because the cells express molecules that inhibit the immune response and they then get a “stem-cell-like ability to revert to an earlier stage of development in which they can persist and proliferate despite immune attack.”
Due to these findings, Dr. Herold said, “The next question is, can we recover these cells so that there is insulin production in someone with type 1 diabetes?”
Dr. Herold and team plan on testing drugs to see if they can change this beta cell subpopulation into insulin-making cells.
Photo Credit: Adobe Stock Photos